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-rw-r--r--target/linux/patches/4.9.3/patch-realtime25614
1 files changed, 25614 insertions, 0 deletions
diff --git a/target/linux/patches/4.9.3/patch-realtime b/target/linux/patches/4.9.3/patch-realtime
new file mode 100644
index 000000000..d3a9ebee7
--- /dev/null
+++ b/target/linux/patches/4.9.3/patch-realtime
@@ -0,0 +1,25614 @@
+diff -Nur linux-4.8.15.orig/arch/arm/include/asm/switch_to.h linux-4.8.15/arch/arm/include/asm/switch_to.h
+--- linux-4.8.15.orig/arch/arm/include/asm/switch_to.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/arm/include/asm/switch_to.h 2017-01-01 17:07:11.543137886 +0100
+@@ -3,6 +3,13 @@
+
+ #include <linux/thread_info.h>
+
++#if defined CONFIG_PREEMPT_RT_FULL && defined CONFIG_HIGHMEM
++void switch_kmaps(struct task_struct *prev_p, struct task_struct *next_p);
++#else
++static inline void
++switch_kmaps(struct task_struct *prev_p, struct task_struct *next_p) { }
++#endif
++
+ /*
+ * For v7 SMP cores running a preemptible kernel we may be pre-empted
+ * during a TLB maintenance operation, so execute an inner-shareable dsb
+@@ -25,6 +32,7 @@
+ #define switch_to(prev,next,last) \
+ do { \
+ __complete_pending_tlbi(); \
++ switch_kmaps(prev, next); \
+ last = __switch_to(prev,task_thread_info(prev), task_thread_info(next)); \
+ } while (0)
+
+diff -Nur linux-4.8.15.orig/arch/arm/include/asm/thread_info.h linux-4.8.15/arch/arm/include/asm/thread_info.h
+--- linux-4.8.15.orig/arch/arm/include/asm/thread_info.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/arm/include/asm/thread_info.h 2017-01-01 17:07:11.547138137 +0100
+@@ -49,6 +49,7 @@
+ struct thread_info {
+ unsigned long flags; /* low level flags */
+ int preempt_count; /* 0 => preemptable, <0 => bug */
++ int preempt_lazy_count; /* 0 => preemptable, <0 => bug */
+ mm_segment_t addr_limit; /* address limit */
+ struct task_struct *task; /* main task structure */
+ __u32 cpu; /* cpu */
+@@ -142,7 +143,8 @@
+ #define TIF_SYSCALL_TRACE 4 /* syscall trace active */
+ #define TIF_SYSCALL_AUDIT 5 /* syscall auditing active */
+ #define TIF_SYSCALL_TRACEPOINT 6 /* syscall tracepoint instrumentation */
+-#define TIF_SECCOMP 7 /* seccomp syscall filtering active */
++#define TIF_SECCOMP 8 /* seccomp syscall filtering active */
++#define TIF_NEED_RESCHED_LAZY 7
+
+ #define TIF_NOHZ 12 /* in adaptive nohz mode */
+ #define TIF_USING_IWMMXT 17
+@@ -152,6 +154,7 @@
+ #define _TIF_SIGPENDING (1 << TIF_SIGPENDING)
+ #define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED)
+ #define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME)
++#define _TIF_NEED_RESCHED_LAZY (1 << TIF_NEED_RESCHED_LAZY)
+ #define _TIF_UPROBE (1 << TIF_UPROBE)
+ #define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE)
+ #define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT)
+@@ -167,7 +170,8 @@
+ * Change these and you break ASM code in entry-common.S
+ */
+ #define _TIF_WORK_MASK (_TIF_NEED_RESCHED | _TIF_SIGPENDING | \
+- _TIF_NOTIFY_RESUME | _TIF_UPROBE)
++ _TIF_NOTIFY_RESUME | _TIF_UPROBE | \
++ _TIF_NEED_RESCHED_LAZY)
+
+ #endif /* __KERNEL__ */
+ #endif /* __ASM_ARM_THREAD_INFO_H */
+diff -Nur linux-4.8.15.orig/arch/arm/Kconfig linux-4.8.15/arch/arm/Kconfig
+--- linux-4.8.15.orig/arch/arm/Kconfig 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/arm/Kconfig 2017-01-01 17:07:11.487134269 +0100
+@@ -36,7 +36,7 @@
+ select HAVE_ARCH_AUDITSYSCALL if (AEABI && !OABI_COMPAT)
+ select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6
+ select HAVE_ARCH_HARDENED_USERCOPY
+- select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
++ select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU && !PREEMPT_RT_BASE
+ select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 && MMU
+ select HAVE_ARCH_MMAP_RND_BITS if MMU
+ select HAVE_ARCH_SECCOMP_FILTER if (AEABI && !OABI_COMPAT)
+@@ -75,6 +75,7 @@
+ select HAVE_PERF_EVENTS
+ select HAVE_PERF_REGS
+ select HAVE_PERF_USER_STACK_DUMP
++ select HAVE_PREEMPT_LAZY
+ select HAVE_RCU_TABLE_FREE if (SMP && ARM_LPAE)
+ select HAVE_REGS_AND_STACK_ACCESS_API
+ select HAVE_SYSCALL_TRACEPOINTS
+diff -Nur linux-4.8.15.orig/arch/arm/kernel/asm-offsets.c linux-4.8.15/arch/arm/kernel/asm-offsets.c
+--- linux-4.8.15.orig/arch/arm/kernel/asm-offsets.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/arm/kernel/asm-offsets.c 2017-01-01 17:07:11.587140711 +0100
+@@ -65,6 +65,7 @@
+ BLANK();
+ DEFINE(TI_FLAGS, offsetof(struct thread_info, flags));
+ DEFINE(TI_PREEMPT, offsetof(struct thread_info, preempt_count));
++ DEFINE(TI_PREEMPT_LAZY, offsetof(struct thread_info, preempt_lazy_count));
+ DEFINE(TI_ADDR_LIMIT, offsetof(struct thread_info, addr_limit));
+ DEFINE(TI_TASK, offsetof(struct thread_info, task));
+ DEFINE(TI_CPU, offsetof(struct thread_info, cpu));
+diff -Nur linux-4.8.15.orig/arch/arm/kernel/entry-armv.S linux-4.8.15/arch/arm/kernel/entry-armv.S
+--- linux-4.8.15.orig/arch/arm/kernel/entry-armv.S 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/arm/kernel/entry-armv.S 2017-01-01 17:07:11.611142259 +0100
+@@ -220,11 +220,18 @@
+
+ #ifdef CONFIG_PREEMPT
+ ldr r8, [tsk, #TI_PREEMPT] @ get preempt count
+- ldr r0, [tsk, #TI_FLAGS] @ get flags
+ teq r8, #0 @ if preempt count != 0
++ bne 1f @ return from exeption
++ ldr r0, [tsk, #TI_FLAGS] @ get flags
++ tst r0, #_TIF_NEED_RESCHED @ if NEED_RESCHED is set
++ blne svc_preempt @ preempt!
++
++ ldr r8, [tsk, #TI_PREEMPT_LAZY] @ get preempt lazy count
++ teq r8, #0 @ if preempt lazy count != 0
+ movne r0, #0 @ force flags to 0
+- tst r0, #_TIF_NEED_RESCHED
++ tst r0, #_TIF_NEED_RESCHED_LAZY
+ blne svc_preempt
++1:
+ #endif
+
+ svc_exit r5, irq = 1 @ return from exception
+@@ -239,8 +246,14 @@
+ 1: bl preempt_schedule_irq @ irq en/disable is done inside
+ ldr r0, [tsk, #TI_FLAGS] @ get new tasks TI_FLAGS
+ tst r0, #_TIF_NEED_RESCHED
++ bne 1b
++ tst r0, #_TIF_NEED_RESCHED_LAZY
+ reteq r8 @ go again
+- b 1b
++ ldr r0, [tsk, #TI_PREEMPT_LAZY] @ get preempt lazy count
++ teq r0, #0 @ if preempt lazy count != 0
++ beq 1b
++ ret r8 @ go again
++
+ #endif
+
+ __und_fault:
+diff -Nur linux-4.8.15.orig/arch/arm/kernel/entry-common.S linux-4.8.15/arch/arm/kernel/entry-common.S
+--- linux-4.8.15.orig/arch/arm/kernel/entry-common.S 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/arm/kernel/entry-common.S 2017-01-01 17:07:11.615142513 +0100
+@@ -36,7 +36,9 @@
+ UNWIND(.cantunwind )
+ disable_irq_notrace @ disable interrupts
+ ldr r1, [tsk, #TI_FLAGS] @ re-check for syscall tracing
+- tst r1, #_TIF_SYSCALL_WORK | _TIF_WORK_MASK
++ tst r1, #((_TIF_SYSCALL_WORK | _TIF_WORK_MASK) & ~_TIF_SECCOMP)
++ bne fast_work_pending
++ tst r1, #_TIF_SECCOMP
+ bne fast_work_pending
+
+ /* perform architecture specific actions before user return */
+@@ -62,8 +64,11 @@
+ str r0, [sp, #S_R0 + S_OFF]! @ save returned r0
+ disable_irq_notrace @ disable interrupts
+ ldr r1, [tsk, #TI_FLAGS] @ re-check for syscall tracing
+- tst r1, #_TIF_SYSCALL_WORK | _TIF_WORK_MASK
++ tst r1, #((_TIF_SYSCALL_WORK | _TIF_WORK_MASK) & ~_TIF_SECCOMP)
++ bne do_slower_path
++ tst r1, #_TIF_SECCOMP
+ beq no_work_pending
++do_slower_path:
+ UNWIND(.fnend )
+ ENDPROC(ret_fast_syscall)
+
+diff -Nur linux-4.8.15.orig/arch/arm/kernel/patch.c linux-4.8.15/arch/arm/kernel/patch.c
+--- linux-4.8.15.orig/arch/arm/kernel/patch.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/arm/kernel/patch.c 2017-01-01 17:07:11.623143039 +0100
+@@ -15,7 +15,7 @@
+ unsigned int insn;
+ };
+
+-static DEFINE_SPINLOCK(patch_lock);
++static DEFINE_RAW_SPINLOCK(patch_lock);
+
+ static void __kprobes *patch_map(void *addr, int fixmap, unsigned long *flags)
+ __acquires(&patch_lock)
+@@ -32,7 +32,7 @@
+ return addr;
+
+ if (flags)
+- spin_lock_irqsave(&patch_lock, *flags);
++ raw_spin_lock_irqsave(&patch_lock, *flags);
+ else
+ __acquire(&patch_lock);
+
+@@ -47,7 +47,7 @@
+ clear_fixmap(fixmap);
+
+ if (flags)
+- spin_unlock_irqrestore(&patch_lock, *flags);
++ raw_spin_unlock_irqrestore(&patch_lock, *flags);
+ else
+ __release(&patch_lock);
+ }
+diff -Nur linux-4.8.15.orig/arch/arm/kernel/process.c linux-4.8.15/arch/arm/kernel/process.c
+--- linux-4.8.15.orig/arch/arm/kernel/process.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/arm/kernel/process.c 2017-01-01 17:07:11.631143548 +0100
+@@ -323,6 +323,30 @@
+ }
+
+ #ifdef CONFIG_MMU
++/*
++ * CONFIG_SPLIT_PTLOCK_CPUS results in a page->ptl lock. If the lock is not
++ * initialized by pgtable_page_ctor() then a coredump of the vector page will
++ * fail.
++ */
++static int __init vectors_user_mapping_init_page(void)
++{
++ struct page *page;
++ unsigned long addr = 0xffff0000;
++ pgd_t *pgd;
++ pud_t *pud;
++ pmd_t *pmd;
++
++ pgd = pgd_offset_k(addr);
++ pud = pud_offset(pgd, addr);
++ pmd = pmd_offset(pud, addr);
++ page = pmd_page(*(pmd));
++
++ pgtable_page_ctor(page);
++
++ return 0;
++}
++late_initcall(vectors_user_mapping_init_page);
++
+ #ifdef CONFIG_KUSER_HELPERS
+ /*
+ * The vectors page is always readable from user space for the
+diff -Nur linux-4.8.15.orig/arch/arm/kernel/signal.c linux-4.8.15/arch/arm/kernel/signal.c
+--- linux-4.8.15.orig/arch/arm/kernel/signal.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/arm/kernel/signal.c 2017-01-01 17:07:11.659145353 +0100
+@@ -572,7 +572,8 @@
+ */
+ trace_hardirqs_off();
+ do {
+- if (likely(thread_flags & _TIF_NEED_RESCHED)) {
++ if (likely(thread_flags & (_TIF_NEED_RESCHED |
++ _TIF_NEED_RESCHED_LAZY))) {
+ schedule();
+ } else {
+ if (unlikely(!user_mode(regs)))
+diff -Nur linux-4.8.15.orig/arch/arm/kernel/smp.c linux-4.8.15/arch/arm/kernel/smp.c
+--- linux-4.8.15.orig/arch/arm/kernel/smp.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/arm/kernel/smp.c 2017-01-01 17:07:11.671146131 +0100
+@@ -234,8 +234,6 @@
+ flush_cache_louis();
+ local_flush_tlb_all();
+
+- clear_tasks_mm_cpumask(cpu);
+-
+ return 0;
+ }
+
+@@ -251,6 +249,9 @@
+ pr_err("CPU%u: cpu didn't die\n", cpu);
+ return;
+ }
++
++ clear_tasks_mm_cpumask(cpu);
++
+ pr_notice("CPU%u: shutdown\n", cpu);
+
+ /*
+diff -Nur linux-4.8.15.orig/arch/arm/kernel/unwind.c linux-4.8.15/arch/arm/kernel/unwind.c
+--- linux-4.8.15.orig/arch/arm/kernel/unwind.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/arm/kernel/unwind.c 2017-01-01 17:07:11.671146131 +0100
+@@ -93,7 +93,7 @@
+ static const struct unwind_idx *__origin_unwind_idx;
+ extern const struct unwind_idx __stop_unwind_idx[];
+
+-static DEFINE_SPINLOCK(unwind_lock);
++static DEFINE_RAW_SPINLOCK(unwind_lock);
+ static LIST_HEAD(unwind_tables);
+
+ /* Convert a prel31 symbol to an absolute address */
+@@ -201,7 +201,7 @@
+ /* module unwind tables */
+ struct unwind_table *table;
+
+- spin_lock_irqsave(&unwind_lock, flags);
++ raw_spin_lock_irqsave(&unwind_lock, flags);
+ list_for_each_entry(table, &unwind_tables, list) {
+ if (addr >= table->begin_addr &&
+ addr < table->end_addr) {
+@@ -213,7 +213,7 @@
+ break;
+ }
+ }
+- spin_unlock_irqrestore(&unwind_lock, flags);
++ raw_spin_unlock_irqrestore(&unwind_lock, flags);
+ }
+
+ pr_debug("%s: idx = %p\n", __func__, idx);
+@@ -529,9 +529,9 @@
+ tab->begin_addr = text_addr;
+ tab->end_addr = text_addr + text_size;
+
+- spin_lock_irqsave(&unwind_lock, flags);
++ raw_spin_lock_irqsave(&unwind_lock, flags);
+ list_add_tail(&tab->list, &unwind_tables);
+- spin_unlock_irqrestore(&unwind_lock, flags);
++ raw_spin_unlock_irqrestore(&unwind_lock, flags);
+
+ return tab;
+ }
+@@ -543,9 +543,9 @@
+ if (!tab)
+ return;
+
+- spin_lock_irqsave(&unwind_lock, flags);
++ raw_spin_lock_irqsave(&unwind_lock, flags);
+ list_del(&tab->list);
+- spin_unlock_irqrestore(&unwind_lock, flags);
++ raw_spin_unlock_irqrestore(&unwind_lock, flags);
+
+ kfree(tab);
+ }
+diff -Nur linux-4.8.15.orig/arch/arm/kvm/arm.c linux-4.8.15/arch/arm/kvm/arm.c
+--- linux-4.8.15.orig/arch/arm/kvm/arm.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/arm/kvm/arm.c 2017-01-01 17:07:11.675146381 +0100
+@@ -584,7 +584,7 @@
+ * involves poking the GIC, which must be done in a
+ * non-preemptible context.
+ */
+- preempt_disable();
++ migrate_disable();
+ kvm_pmu_flush_hwstate(vcpu);
+ kvm_timer_flush_hwstate(vcpu);
+ kvm_vgic_flush_hwstate(vcpu);
+@@ -605,7 +605,7 @@
+ kvm_pmu_sync_hwstate(vcpu);
+ kvm_timer_sync_hwstate(vcpu);
+ kvm_vgic_sync_hwstate(vcpu);
+- preempt_enable();
++ migrate_enable();
+ continue;
+ }
+
+@@ -661,7 +661,7 @@
+
+ kvm_vgic_sync_hwstate(vcpu);
+
+- preempt_enable();
++ migrate_enable();
+
+ ret = handle_exit(vcpu, run, ret);
+ }
+diff -Nur linux-4.8.15.orig/arch/arm/mach-exynos/platsmp.c linux-4.8.15/arch/arm/mach-exynos/platsmp.c
+--- linux-4.8.15.orig/arch/arm/mach-exynos/platsmp.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/arm/mach-exynos/platsmp.c 2017-01-01 17:07:11.707148443 +0100
+@@ -229,7 +229,7 @@
+ return (void __iomem *)(S5P_VA_SCU);
+ }
+
+-static DEFINE_SPINLOCK(boot_lock);
++static DEFINE_RAW_SPINLOCK(boot_lock);
+
+ static void exynos_secondary_init(unsigned int cpu)
+ {
+@@ -242,8 +242,8 @@
+ /*
+ * Synchronise with the boot thread.
+ */
+- spin_lock(&boot_lock);
+- spin_unlock(&boot_lock);
++ raw_spin_lock(&boot_lock);
++ raw_spin_unlock(&boot_lock);
+ }
+
+ int exynos_set_boot_addr(u32 core_id, unsigned long boot_addr)
+@@ -307,7 +307,7 @@
+ * Set synchronisation state between this boot processor
+ * and the secondary one
+ */
+- spin_lock(&boot_lock);
++ raw_spin_lock(&boot_lock);
+
+ /*
+ * The secondary processor is waiting to be released from
+@@ -334,7 +334,7 @@
+
+ if (timeout == 0) {
+ printk(KERN_ERR "cpu1 power enable failed");
+- spin_unlock(&boot_lock);
++ raw_spin_unlock(&boot_lock);
+ return -ETIMEDOUT;
+ }
+ }
+@@ -380,7 +380,7 @@
+ * calibrations, then wait for it to finish
+ */
+ fail:
+- spin_unlock(&boot_lock);
++ raw_spin_unlock(&boot_lock);
+
+ return pen_release != -1 ? ret : 0;
+ }
+diff -Nur linux-4.8.15.orig/arch/arm/mach-hisi/platmcpm.c linux-4.8.15/arch/arm/mach-hisi/platmcpm.c
+--- linux-4.8.15.orig/arch/arm/mach-hisi/platmcpm.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/arm/mach-hisi/platmcpm.c 2017-01-01 17:07:11.747151017 +0100
+@@ -61,7 +61,7 @@
+
+ static void __iomem *sysctrl, *fabric;
+ static int hip04_cpu_table[HIP04_MAX_CLUSTERS][HIP04_MAX_CPUS_PER_CLUSTER];
+-static DEFINE_SPINLOCK(boot_lock);
++static DEFINE_RAW_SPINLOCK(boot_lock);
+ static u32 fabric_phys_addr;
+ /*
+ * [0]: bootwrapper physical address
+@@ -113,7 +113,7 @@
+ if (cluster >= HIP04_MAX_CLUSTERS || cpu >= HIP04_MAX_CPUS_PER_CLUSTER)
+ return -EINVAL;
+
+- spin_lock_irq(&boot_lock);
++ raw_spin_lock_irq(&boot_lock);
+
+ if (hip04_cpu_table[cluster][cpu])
+ goto out;
+@@ -147,7 +147,7 @@
+
+ out:
+ hip04_cpu_table[cluster][cpu]++;
+- spin_unlock_irq(&boot_lock);
++ raw_spin_unlock_irq(&boot_lock);
+
+ return 0;
+ }
+@@ -162,11 +162,11 @@
+ cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
+ cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
+
+- spin_lock(&boot_lock);
++ raw_spin_lock(&boot_lock);
+ hip04_cpu_table[cluster][cpu]--;
+ if (hip04_cpu_table[cluster][cpu] == 1) {
+ /* A power_up request went ahead of us. */
+- spin_unlock(&boot_lock);
++ raw_spin_unlock(&boot_lock);
+ return;
+ } else if (hip04_cpu_table[cluster][cpu] > 1) {
+ pr_err("Cluster %d CPU%d boots multiple times\n", cluster, cpu);
+@@ -174,7 +174,7 @@
+ }
+
+ last_man = hip04_cluster_is_down(cluster);
+- spin_unlock(&boot_lock);
++ raw_spin_unlock(&boot_lock);
+ if (last_man) {
+ /* Since it's Cortex A15, disable L2 prefetching. */
+ asm volatile(
+@@ -203,7 +203,7 @@
+ cpu >= HIP04_MAX_CPUS_PER_CLUSTER);
+
+ count = TIMEOUT_MSEC / POLL_MSEC;
+- spin_lock_irq(&boot_lock);
++ raw_spin_lock_irq(&boot_lock);
+ for (tries = 0; tries < count; tries++) {
+ if (hip04_cpu_table[cluster][cpu])
+ goto err;
+@@ -211,10 +211,10 @@
+ data = readl_relaxed(sysctrl + SC_CPU_RESET_STATUS(cluster));
+ if (data & CORE_WFI_STATUS(cpu))
+ break;
+- spin_unlock_irq(&boot_lock);
++ raw_spin_unlock_irq(&boot_lock);
+ /* Wait for clean L2 when the whole cluster is down. */
+ msleep(POLL_MSEC);
+- spin_lock_irq(&boot_lock);
++ raw_spin_lock_irq(&boot_lock);
+ }
+ if (tries >= count)
+ goto err;
+@@ -231,10 +231,10 @@
+ goto err;
+ if (hip04_cluster_is_down(cluster))
+ hip04_set_snoop_filter(cluster, 0);
+- spin_unlock_irq(&boot_lock);
++ raw_spin_unlock_irq(&boot_lock);
+ return 1;
+ err:
+- spin_unlock_irq(&boot_lock);
++ raw_spin_unlock_irq(&boot_lock);
+ return 0;
+ }
+ #endif
+diff -Nur linux-4.8.15.orig/arch/arm/mach-omap2/omap-smp.c linux-4.8.15/arch/arm/mach-omap2/omap-smp.c
+--- linux-4.8.15.orig/arch/arm/mach-omap2/omap-smp.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/arm/mach-omap2/omap-smp.c 2017-01-01 17:07:11.763152049 +0100
+@@ -64,7 +64,7 @@
+ .startup_addr = omap5_secondary_startup,
+ };
+
+-static DEFINE_SPINLOCK(boot_lock);
++static DEFINE_RAW_SPINLOCK(boot_lock);
+
+ void __iomem *omap4_get_scu_base(void)
+ {
+@@ -131,8 +131,8 @@
+ /*
+ * Synchronise with the boot thread.
+ */
+- spin_lock(&boot_lock);
+- spin_unlock(&boot_lock);
++ raw_spin_lock(&boot_lock);
++ raw_spin_unlock(&boot_lock);
+ }
+
+ static int omap4_boot_secondary(unsigned int cpu, struct task_struct *idle)
+@@ -146,7 +146,7 @@
+ * Set synchronisation state between this boot processor
+ * and the secondary one
+ */
+- spin_lock(&boot_lock);
++ raw_spin_lock(&boot_lock);
+
+ /*
+ * Update the AuxCoreBoot0 with boot state for secondary core.
+@@ -223,7 +223,7 @@
+ * Now the secondary core is starting up let it run its
+ * calibrations, then wait for it to finish
+ */
+- spin_unlock(&boot_lock);
++ raw_spin_unlock(&boot_lock);
+
+ return 0;
+ }
+diff -Nur linux-4.8.15.orig/arch/arm/mach-prima2/platsmp.c linux-4.8.15/arch/arm/mach-prima2/platsmp.c
+--- linux-4.8.15.orig/arch/arm/mach-prima2/platsmp.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/arm/mach-prima2/platsmp.c 2017-01-01 17:07:11.795154111 +0100
+@@ -22,7 +22,7 @@
+
+ static void __iomem *clk_base;
+
+-static DEFINE_SPINLOCK(boot_lock);
++static DEFINE_RAW_SPINLOCK(boot_lock);
+
+ static void sirfsoc_secondary_init(unsigned int cpu)
+ {
+@@ -36,8 +36,8 @@
+ /*
+ * Synchronise with the boot thread.
+ */
+- spin_lock(&boot_lock);
+- spin_unlock(&boot_lock);
++ raw_spin_lock(&boot_lock);
++ raw_spin_unlock(&boot_lock);
+ }
+
+ static const struct of_device_id clk_ids[] = {
+@@ -75,7 +75,7 @@
+ /* make sure write buffer is drained */
+ mb();
+
+- spin_lock(&boot_lock);
++ raw_spin_lock(&boot_lock);
+
+ /*
+ * The secondary processor is waiting to be released from
+@@ -107,7 +107,7 @@
+ * now the secondary core is starting up let it run its
+ * calibrations, then wait for it to finish
+ */
+- spin_unlock(&boot_lock);
++ raw_spin_unlock(&boot_lock);
+
+ return pen_release != -1 ? -ENOSYS : 0;
+ }
+diff -Nur linux-4.8.15.orig/arch/arm/mach-qcom/platsmp.c linux-4.8.15/arch/arm/mach-qcom/platsmp.c
+--- linux-4.8.15.orig/arch/arm/mach-qcom/platsmp.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/arm/mach-qcom/platsmp.c 2017-01-01 17:07:11.803154626 +0100
+@@ -46,7 +46,7 @@
+
+ extern void secondary_startup_arm(void);
+
+-static DEFINE_SPINLOCK(boot_lock);
++static DEFINE_RAW_SPINLOCK(boot_lock);
+
+ #ifdef CONFIG_HOTPLUG_CPU
+ static void qcom_cpu_die(unsigned int cpu)
+@@ -60,8 +60,8 @@
+ /*
+ * Synchronise with the boot thread.
+ */
+- spin_lock(&boot_lock);
+- spin_unlock(&boot_lock);
++ raw_spin_lock(&boot_lock);
++ raw_spin_unlock(&boot_lock);
+ }
+
+ static int scss_release_secondary(unsigned int cpu)
+@@ -284,7 +284,7 @@
+ * set synchronisation state between this boot processor
+ * and the secondary one
+ */
+- spin_lock(&boot_lock);
++ raw_spin_lock(&boot_lock);
+
+ /*
+ * Send the secondary CPU a soft interrupt, thereby causing
+@@ -297,7 +297,7 @@
+ * now the secondary core is starting up let it run its
+ * calibrations, then wait for it to finish
+ */
+- spin_unlock(&boot_lock);
++ raw_spin_unlock(&boot_lock);
+
+ return ret;
+ }
+diff -Nur linux-4.8.15.orig/arch/arm/mach-spear/platsmp.c linux-4.8.15/arch/arm/mach-spear/platsmp.c
+--- linux-4.8.15.orig/arch/arm/mach-spear/platsmp.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/arm/mach-spear/platsmp.c 2017-01-01 17:07:11.847157467 +0100
+@@ -32,7 +32,7 @@
+ sync_cache_w(&pen_release);
+ }
+
+-static DEFINE_SPINLOCK(boot_lock);
++static DEFINE_RAW_SPINLOCK(boot_lock);
+
+ static void __iomem *scu_base = IOMEM(VA_SCU_BASE);
+
+@@ -47,8 +47,8 @@
+ /*
+ * Synchronise with the boot thread.
+ */
+- spin_lock(&boot_lock);
+- spin_unlock(&boot_lock);
++ raw_spin_lock(&boot_lock);
++ raw_spin_unlock(&boot_lock);
+ }
+
+ static int spear13xx_boot_secondary(unsigned int cpu, struct task_struct *idle)
+@@ -59,7 +59,7 @@
+ * set synchronisation state between this boot processor
+ * and the secondary one
+ */
+- spin_lock(&boot_lock);
++ raw_spin_lock(&boot_lock);
+
+ /*
+ * The secondary processor is waiting to be released from
+@@ -84,7 +84,7 @@
+ * now the secondary core is starting up let it run its
+ * calibrations, then wait for it to finish
+ */
+- spin_unlock(&boot_lock);
++ raw_spin_unlock(&boot_lock);
+
+ return pen_release != -1 ? -ENOSYS : 0;
+ }
+diff -Nur linux-4.8.15.orig/arch/arm/mach-sti/platsmp.c linux-4.8.15/arch/arm/mach-sti/platsmp.c
+--- linux-4.8.15.orig/arch/arm/mach-sti/platsmp.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/arm/mach-sti/platsmp.c 2017-01-01 17:07:11.851157720 +0100
+@@ -35,7 +35,7 @@
+ sync_cache_w(&pen_release);
+ }
+
+-static DEFINE_SPINLOCK(boot_lock);
++static DEFINE_RAW_SPINLOCK(boot_lock);
+
+ static void sti_secondary_init(unsigned int cpu)
+ {
+@@ -48,8 +48,8 @@
+ /*
+ * Synchronise with the boot thread.
+ */
+- spin_lock(&boot_lock);
+- spin_unlock(&boot_lock);
++ raw_spin_lock(&boot_lock);
++ raw_spin_unlock(&boot_lock);
+ }
+
+ static int sti_boot_secondary(unsigned int cpu, struct task_struct *idle)
+@@ -60,7 +60,7 @@
+ * set synchronisation state between this boot processor
+ * and the secondary one
+ */
+- spin_lock(&boot_lock);
++ raw_spin_lock(&boot_lock);
+
+ /*
+ * The secondary processor is waiting to be released from
+@@ -91,7 +91,7 @@
+ * now the secondary core is starting up let it run its
+ * calibrations, then wait for it to finish
+ */
+- spin_unlock(&boot_lock);
++ raw_spin_unlock(&boot_lock);
+
+ return pen_release != -1 ? -ENOSYS : 0;
+ }
+diff -Nur linux-4.8.15.orig/arch/arm/mm/fault.c linux-4.8.15/arch/arm/mm/fault.c
+--- linux-4.8.15.orig/arch/arm/mm/fault.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/arm/mm/fault.c 2017-01-01 17:07:11.879159524 +0100
+@@ -430,6 +430,9 @@
+ if (addr < TASK_SIZE)
+ return do_page_fault(addr, fsr, regs);
+
++ if (interrupts_enabled(regs))
++ local_irq_enable();
++
+ if (user_mode(regs))
+ goto bad_area;
+
+@@ -497,6 +500,9 @@
+ static int
+ do_sect_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
+ {
++ if (interrupts_enabled(regs))
++ local_irq_enable();
++
+ do_bad_area(addr, fsr, regs);
+ return 0;
+ }
+diff -Nur linux-4.8.15.orig/arch/arm/mm/highmem.c linux-4.8.15/arch/arm/mm/highmem.c
+--- linux-4.8.15.orig/arch/arm/mm/highmem.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/arm/mm/highmem.c 2017-01-01 17:07:11.879159524 +0100
+@@ -34,6 +34,11 @@
+ return *ptep;
+ }
+
++static unsigned int fixmap_idx(int type)
++{
++ return FIX_KMAP_BEGIN + type + KM_TYPE_NR * smp_processor_id();
++}
++
+ void *kmap(struct page *page)
+ {
+ might_sleep();
+@@ -54,12 +59,13 @@
+
+ void *kmap_atomic(struct page *page)
+ {
++ pte_t pte = mk_pte(page, kmap_prot);
+ unsigned int idx;
+ unsigned long vaddr;
+ void *kmap;
+ int type;
+
+- preempt_disable();
++ preempt_disable_nort();
+ pagefault_disable();
+ if (!PageHighMem(page))
+ return page_address(page);
+@@ -79,7 +85,7 @@
+
+ type = kmap_atomic_idx_push();
+
+- idx = FIX_KMAP_BEGIN + type + KM_TYPE_NR * smp_processor_id();
++ idx = fixmap_idx(type);
+ vaddr = __fix_to_virt(idx);
+ #ifdef CONFIG_DEBUG_HIGHMEM
+ /*
+@@ -93,7 +99,10 @@
+ * in place, so the contained TLB flush ensures the TLB is updated
+ * with the new mapping.
+ */
+- set_fixmap_pte(idx, mk_pte(page, kmap_prot));
++#ifdef CONFIG_PREEMPT_RT_FULL
++ current->kmap_pte[type] = pte;
++#endif
++ set_fixmap_pte(idx, pte);
+
+ return (void *)vaddr;
+ }
+@@ -106,44 +115,75 @@
+
+ if (kvaddr >= (void *)FIXADDR_START) {
+ type = kmap_atomic_idx();
+- idx = FIX_KMAP_BEGIN + type + KM_TYPE_NR * smp_processor_id();
++ idx = fixmap_idx(type);
+
+ if (cache_is_vivt())
+ __cpuc_flush_dcache_area((void *)vaddr, PAGE_SIZE);
++#ifdef CONFIG_PREEMPT_RT_FULL
++ current->kmap_pte[type] = __pte(0);
++#endif
+ #ifdef CONFIG_DEBUG_HIGHMEM
+ BUG_ON(vaddr != __fix_to_virt(idx));
+- set_fixmap_pte(idx, __pte(0));
+ #else
+ (void) idx; /* to kill a warning */
+ #endif
++ set_fixmap_pte(idx, __pte(0));
+ kmap_atomic_idx_pop();
+ } else if (vaddr >= PKMAP_ADDR(0) && vaddr < PKMAP_ADDR(LAST_PKMAP)) {
+ /* this address was obtained through kmap_high_get() */
+ kunmap_high(pte_page(pkmap_page_table[PKMAP_NR(vaddr)]));
+ }
+ pagefault_enable();
+- preempt_enable();
++ preempt_enable_nort();
+ }
+ EXPORT_SYMBOL(__kunmap_atomic);
+
+ void *kmap_atomic_pfn(unsigned long pfn)
+ {
++ pte_t pte = pfn_pte(pfn, kmap_prot);
+ unsigned long vaddr;
+ int idx, type;
+ struct page *page = pfn_to_page(pfn);
+
+- preempt_disable();
++ preempt_disable_nort();
+ pagefault_disable();
+ if (!PageHighMem(page))
+ return page_address(page);
+
+ type = kmap_atomic_idx_push();
+- idx = FIX_KMAP_BEGIN + type + KM_TYPE_NR * smp_processor_id();
++ idx = fixmap_idx(type);
+ vaddr = __fix_to_virt(idx);
+ #ifdef CONFIG_DEBUG_HIGHMEM
+ BUG_ON(!pte_none(get_fixmap_pte(vaddr)));
+ #endif
+- set_fixmap_pte(idx, pfn_pte(pfn, kmap_prot));
++#ifdef CONFIG_PREEMPT_RT_FULL
++ current->kmap_pte[type] = pte;
++#endif
++ set_fixmap_pte(idx, pte);
+
+ return (void *)vaddr;
+ }
++#if defined CONFIG_PREEMPT_RT_FULL
++void switch_kmaps(struct task_struct *prev_p, struct task_struct *next_p)
++{
++ int i;
++
++ /*
++ * Clear @prev's kmap_atomic mappings
++ */
++ for (i = 0; i < prev_p->kmap_idx; i++) {
++ int idx = fixmap_idx(i);
++
++ set_fixmap_pte(idx, __pte(0));
++ }
++ /*
++ * Restore @next_p's kmap_atomic mappings
++ */
++ for (i = 0; i < next_p->kmap_idx; i++) {
++ int idx = fixmap_idx(i);
++
++ if (!pte_none(next_p->kmap_pte[i]))
++ set_fixmap_pte(idx, next_p->kmap_pte[i]);
++ }
++}
++#endif
+diff -Nur linux-4.8.15.orig/arch/arm/plat-versatile/platsmp.c linux-4.8.15/arch/arm/plat-versatile/platsmp.c
+--- linux-4.8.15.orig/arch/arm/plat-versatile/platsmp.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/arm/plat-versatile/platsmp.c 2017-01-01 17:07:11.939163389 +0100
+@@ -32,7 +32,7 @@
+ sync_cache_w(&pen_release);
+ }
+
+-static DEFINE_SPINLOCK(boot_lock);
++static DEFINE_RAW_SPINLOCK(boot_lock);
+
+ void versatile_secondary_init(unsigned int cpu)
+ {
+@@ -45,8 +45,8 @@
+ /*
+ * Synchronise with the boot thread.
+ */
+- spin_lock(&boot_lock);
+- spin_unlock(&boot_lock);
++ raw_spin_lock(&boot_lock);
++ raw_spin_unlock(&boot_lock);
+ }
+
+ int versatile_boot_secondary(unsigned int cpu, struct task_struct *idle)
+@@ -57,7 +57,7 @@
+ * Set synchronisation state between this boot processor
+ * and the secondary one
+ */
+- spin_lock(&boot_lock);
++ raw_spin_lock(&boot_lock);
+
+ /*
+ * This is really belt and braces; we hold unintended secondary
+@@ -87,7 +87,7 @@
+ * now the secondary core is starting up let it run its
+ * calibrations, then wait for it to finish
+ */
+- spin_unlock(&boot_lock);
++ raw_spin_unlock(&boot_lock);
+
+ return pen_release != -1 ? -ENOSYS : 0;
+ }
+diff -Nur linux-4.8.15.orig/arch/arm64/include/asm/thread_info.h linux-4.8.15/arch/arm64/include/asm/thread_info.h
+--- linux-4.8.15.orig/arch/arm64/include/asm/thread_info.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/arm64/include/asm/thread_info.h 2017-01-01 17:07:12.027169062 +0100
+@@ -49,6 +49,7 @@
+ mm_segment_t addr_limit; /* address limit */
+ struct task_struct *task; /* main task structure */
+ int preempt_count; /* 0 => preemptable, <0 => bug */
++ int preempt_lazy_count; /* 0 => preemptable, <0 => bug */
+ int cpu; /* cpu */
+ };
+
+@@ -109,6 +110,7 @@
+ #define TIF_NEED_RESCHED 1
+ #define TIF_NOTIFY_RESUME 2 /* callback before returning to user */
+ #define TIF_FOREIGN_FPSTATE 3 /* CPU's FP state is not current's */
++#define TIF_NEED_RESCHED_LAZY 4
+ #define TIF_NOHZ 7
+ #define TIF_SYSCALL_TRACE 8
+ #define TIF_SYSCALL_AUDIT 9
+@@ -124,6 +126,7 @@
+ #define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED)
+ #define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME)
+ #define _TIF_FOREIGN_FPSTATE (1 << TIF_FOREIGN_FPSTATE)
++#define _TIF_NEED_RESCHED_LAZY (1 << TIF_NEED_RESCHED_LAZY)
+ #define _TIF_NOHZ (1 << TIF_NOHZ)
+ #define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE)
+ #define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT)
+@@ -132,7 +135,8 @@
+ #define _TIF_32BIT (1 << TIF_32BIT)
+
+ #define _TIF_WORK_MASK (_TIF_NEED_RESCHED | _TIF_SIGPENDING | \
+- _TIF_NOTIFY_RESUME | _TIF_FOREIGN_FPSTATE)
++ _TIF_NOTIFY_RESUME | _TIF_FOREIGN_FPSTATE | \
++ _TIF_NEED_RESCHED_LAZY)
+
+ #define _TIF_SYSCALL_WORK (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \
+ _TIF_SYSCALL_TRACEPOINT | _TIF_SECCOMP | \
+diff -Nur linux-4.8.15.orig/arch/arm64/Kconfig linux-4.8.15/arch/arm64/Kconfig
+--- linux-4.8.15.orig/arch/arm64/Kconfig 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/arm64/Kconfig 2017-01-01 17:07:11.979165970 +0100
+@@ -90,6 +90,7 @@
+ select HAVE_PERF_EVENTS
+ select HAVE_PERF_REGS
+ select HAVE_PERF_USER_STACK_DUMP
++ select HAVE_PREEMPT_LAZY
+ select HAVE_REGS_AND_STACK_ACCESS_API
+ select HAVE_RCU_TABLE_FREE
+ select HAVE_SYSCALL_TRACEPOINTS
+@@ -689,7 +690,7 @@
+
+ config XEN
+ bool "Xen guest support on ARM64"
+- depends on ARM64 && OF
++ depends on ARM64 && OF && !PREEMPT_RT_FULL
+ select SWIOTLB_XEN
+ select PARAVIRT
+ help
+diff -Nur linux-4.8.15.orig/arch/arm64/kernel/asm-offsets.c linux-4.8.15/arch/arm64/kernel/asm-offsets.c
+--- linux-4.8.15.orig/arch/arm64/kernel/asm-offsets.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/arm64/kernel/asm-offsets.c 2017-01-01 17:07:12.079172403 +0100
+@@ -37,6 +37,7 @@
+ BLANK();
+ DEFINE(TI_FLAGS, offsetof(struct thread_info, flags));
+ DEFINE(TI_PREEMPT, offsetof(struct thread_info, preempt_count));
++ DEFINE(TI_PREEMPT_LAZY, offsetof(struct thread_info, preempt_lazy_count));
+ DEFINE(TI_ADDR_LIMIT, offsetof(struct thread_info, addr_limit));
+ DEFINE(TI_TASK, offsetof(struct thread_info, task));
+ DEFINE(TI_CPU, offsetof(struct thread_info, cpu));
+diff -Nur linux-4.8.15.orig/arch/arm64/kernel/entry.S linux-4.8.15/arch/arm64/kernel/entry.S
+--- linux-4.8.15.orig/arch/arm64/kernel/entry.S 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/arm64/kernel/entry.S 2017-01-01 17:07:12.083172658 +0100
+@@ -434,11 +434,16 @@
+
+ #ifdef CONFIG_PREEMPT
+ ldr w24, [tsk, #TI_PREEMPT] // get preempt count
+- cbnz w24, 1f // preempt count != 0
++ cbnz w24, 2f // preempt count != 0
+ ldr x0, [tsk, #TI_FLAGS] // get flags
+- tbz x0, #TIF_NEED_RESCHED, 1f // needs rescheduling?
+- bl el1_preempt
++ tbnz x0, #TIF_NEED_RESCHED, 1f // needs rescheduling?
++
++ ldr w24, [tsk, #TI_PREEMPT_LAZY] // get preempt lazy count
++ cbnz w24, 2f // preempt lazy count != 0
++ tbz x0, #TIF_NEED_RESCHED_LAZY, 2f // needs rescheduling?
+ 1:
++ bl el1_preempt
++2:
+ #endif
+ #ifdef CONFIG_TRACE_IRQFLAGS
+ bl trace_hardirqs_on
+@@ -452,6 +457,7 @@
+ 1: bl preempt_schedule_irq // irq en/disable is done inside
+ ldr x0, [tsk, #TI_FLAGS] // get new tasks TI_FLAGS
+ tbnz x0, #TIF_NEED_RESCHED, 1b // needs rescheduling?
++ tbnz x0, #TIF_NEED_RESCHED_LAZY, 1b // needs rescheduling?
+ ret x24
+ #endif
+
+@@ -708,6 +714,7 @@
+ */
+ work_pending:
+ tbnz x1, #TIF_NEED_RESCHED, work_resched
++ tbnz x1, #TIF_NEED_RESCHED_LAZY, work_resched
+ /* TIF_SIGPENDING, TIF_NOTIFY_RESUME or TIF_FOREIGN_FPSTATE case */
+ mov x0, sp // 'regs'
+ enable_irq // enable interrupts for do_notify_resume()
+diff -Nur linux-4.8.15.orig/arch/Kconfig linux-4.8.15/arch/Kconfig
+--- linux-4.8.15.orig/arch/Kconfig 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/Kconfig 2017-01-01 17:07:11.431130672 +0100
+@@ -9,6 +9,7 @@
+ tristate "OProfile system profiling"
+ depends on PROFILING
+ depends on HAVE_OPROFILE
++ depends on !PREEMPT_RT_FULL
+ select RING_BUFFER
+ select RING_BUFFER_ALLOW_SWAP
+ help
+@@ -52,6 +53,7 @@
+ config JUMP_LABEL
+ bool "Optimize very unlikely/likely branches"
+ depends on HAVE_ARCH_JUMP_LABEL
++ depends on (!INTERRUPT_OFF_HIST && !PREEMPT_OFF_HIST && !WAKEUP_LATENCY_HIST && !MISSED_TIMER_OFFSETS_HIST)
+ help
+ This option enables a transparent branch optimization that
+ makes certain almost-always-true or almost-always-false branch
+diff -Nur linux-4.8.15.orig/arch/mips/Kconfig linux-4.8.15/arch/mips/Kconfig
+--- linux-4.8.15.orig/arch/mips/Kconfig 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/mips/Kconfig 2017-01-01 17:07:12.275185025 +0100
+@@ -2480,7 +2480,7 @@
+ #
+ config HIGHMEM
+ bool "High Memory Support"
+- depends on 32BIT && CPU_SUPPORTS_HIGHMEM && SYS_SUPPORTS_HIGHMEM && !CPU_MIPS32_3_5_EVA
++ depends on 32BIT && CPU_SUPPORTS_HIGHMEM && SYS_SUPPORTS_HIGHMEM && !CPU_MIPS32_3_5_EVA && !PREEMPT_RT_FULL
+
+ config CPU_SUPPORTS_HIGHMEM
+ bool
+diff -Nur linux-4.8.15.orig/arch/powerpc/include/asm/thread_info.h linux-4.8.15/arch/powerpc/include/asm/thread_info.h
+--- linux-4.8.15.orig/arch/powerpc/include/asm/thread_info.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/powerpc/include/asm/thread_info.h 2017-01-01 17:07:12.499199453 +0100
+@@ -43,6 +43,8 @@
+ int cpu; /* cpu we're on */
+ int preempt_count; /* 0 => preemptable,
+ <0 => BUG */
++ int preempt_lazy_count; /* 0 => preemptable,
++ <0 => BUG */
+ unsigned long local_flags; /* private flags for thread */
+ #ifdef CONFIG_LIVEPATCH
+ unsigned long *livepatch_sp;
+@@ -88,8 +90,7 @@
+ #define TIF_SYSCALL_TRACE 0 /* syscall trace active */
+ #define TIF_SIGPENDING 1 /* signal pending */
+ #define TIF_NEED_RESCHED 2 /* rescheduling necessary */
+-#define TIF_POLLING_NRFLAG 3 /* true if poll_idle() is polling
+- TIF_NEED_RESCHED */
++#define TIF_NEED_RESCHED_LAZY 3 /* lazy rescheduling necessary */
+ #define TIF_32BIT 4 /* 32 bit binary */
+ #define TIF_RESTORE_TM 5 /* need to restore TM FP/VEC/VSX */
+ #define TIF_SYSCALL_AUDIT 7 /* syscall auditing active */
+@@ -107,6 +108,8 @@
+ #if defined(CONFIG_PPC64)
+ #define TIF_ELF2ABI 18 /* function descriptors must die! */
+ #endif
++#define TIF_POLLING_NRFLAG 19 /* true if poll_idle() is polling
++ TIF_NEED_RESCHED */
+
+ /* as above, but as bit values */
+ #define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE)
+@@ -125,14 +128,16 @@
+ #define _TIF_SYSCALL_TRACEPOINT (1<<TIF_SYSCALL_TRACEPOINT)
+ #define _TIF_EMULATE_STACK_STORE (1<<TIF_EMULATE_STACK_STORE)
+ #define _TIF_NOHZ (1<<TIF_NOHZ)
++#define _TIF_NEED_RESCHED_LAZY (1<<TIF_NEED_RESCHED_LAZY)
+ #define _TIF_SYSCALL_DOTRACE (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \
+ _TIF_SECCOMP | _TIF_SYSCALL_TRACEPOINT | \
+ _TIF_NOHZ)
+
+ #define _TIF_USER_WORK_MASK (_TIF_SIGPENDING | _TIF_NEED_RESCHED | \
+ _TIF_NOTIFY_RESUME | _TIF_UPROBE | \
+- _TIF_RESTORE_TM)
++ _TIF_RESTORE_TM | _TIF_NEED_RESCHED_LAZY)
+ #define _TIF_PERSYSCALL_MASK (_TIF_RESTOREALL|_TIF_NOERROR)
++#define _TIF_NEED_RESCHED_MASK (_TIF_NEED_RESCHED | _TIF_NEED_RESCHED_LAZY)
+
+ /* Bits in local_flags */
+ /* Don't move TLF_NAPPING without adjusting the code in entry_32.S */
+diff -Nur linux-4.8.15.orig/arch/powerpc/Kconfig linux-4.8.15/arch/powerpc/Kconfig
+--- linux-4.8.15.orig/arch/powerpc/Kconfig 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/powerpc/Kconfig 2017-01-01 17:07:12.435195331 +0100
+@@ -57,10 +57,11 @@
+
+ config RWSEM_GENERIC_SPINLOCK
+ bool
++ default y if PREEMPT_RT_FULL
+
+ config RWSEM_XCHGADD_ALGORITHM
+ bool
+- default y
++ default y if !PREEMPT_RT_FULL
+
+ config GENERIC_LOCKBREAK
+ bool
+@@ -140,6 +141,7 @@
+ select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
+ select GENERIC_STRNCPY_FROM_USER
+ select GENERIC_STRNLEN_USER
++ select HAVE_PREEMPT_LAZY
+ select HAVE_MOD_ARCH_SPECIFIC
+ select MODULES_USE_ELF_RELA
+ select CLONE_BACKWARDS
+@@ -326,7 +328,7 @@
+
+ config HIGHMEM
+ bool "High memory support"
+- depends on PPC32
++ depends on PPC32 && !PREEMPT_RT_FULL
+
+ source kernel/Kconfig.hz
+ source kernel/Kconfig.preempt
+diff -Nur linux-4.8.15.orig/arch/powerpc/kernel/asm-offsets.c linux-4.8.15/arch/powerpc/kernel/asm-offsets.c
+--- linux-4.8.15.orig/arch/powerpc/kernel/asm-offsets.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/powerpc/kernel/asm-offsets.c 2017-01-01 17:07:12.519200744 +0100
+@@ -156,6 +156,7 @@
+ DEFINE(TI_FLAGS, offsetof(struct thread_info, flags));
+ DEFINE(TI_LOCAL_FLAGS, offsetof(struct thread_info, local_flags));
+ DEFINE(TI_PREEMPT, offsetof(struct thread_info, preempt_count));
++ DEFINE(TI_PREEMPT_LAZY, offsetof(struct thread_info, preempt_lazy_count));
+ DEFINE(TI_TASK, offsetof(struct thread_info, task));
+ DEFINE(TI_CPU, offsetof(struct thread_info, cpu));
+
+diff -Nur linux-4.8.15.orig/arch/powerpc/kernel/entry_32.S linux-4.8.15/arch/powerpc/kernel/entry_32.S
+--- linux-4.8.15.orig/arch/powerpc/kernel/entry_32.S 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/powerpc/kernel/entry_32.S 2017-01-01 17:07:12.531201514 +0100
+@@ -835,7 +835,14 @@
+ cmpwi 0,r0,0 /* if non-zero, just restore regs and return */
+ bne restore
+ andi. r8,r8,_TIF_NEED_RESCHED
++ bne+ 1f
++ lwz r0,TI_PREEMPT_LAZY(r9)
++ cmpwi 0,r0,0 /* if non-zero, just restore regs and return */
++ bne restore
++ lwz r0,TI_FLAGS(r9)
++ andi. r0,r0,_TIF_NEED_RESCHED_LAZY
+ beq+ restore
++1:
+ lwz r3,_MSR(r1)
+ andi. r0,r3,MSR_EE /* interrupts off? */
+ beq restore /* don't schedule if so */
+@@ -846,11 +853,11 @@
+ */
+ bl trace_hardirqs_off
+ #endif
+-1: bl preempt_schedule_irq
++2: bl preempt_schedule_irq
+ CURRENT_THREAD_INFO(r9, r1)
+ lwz r3,TI_FLAGS(r9)
+- andi. r0,r3,_TIF_NEED_RESCHED
+- bne- 1b
++ andi. r0,r3,_TIF_NEED_RESCHED_MASK
++ bne- 2b
+ #ifdef CONFIG_TRACE_IRQFLAGS
+ /* And now, to properly rebalance the above, we tell lockdep they
+ * are being turned back on, which will happen when we return
+@@ -1171,7 +1178,7 @@
+ #endif /* !(CONFIG_4xx || CONFIG_BOOKE) */
+
+ do_work: /* r10 contains MSR_KERNEL here */
+- andi. r0,r9,_TIF_NEED_RESCHED
++ andi. r0,r9,_TIF_NEED_RESCHED_MASK
+ beq do_user_signal
+
+ do_resched: /* r10 contains MSR_KERNEL here */
+@@ -1192,7 +1199,7 @@
+ MTMSRD(r10) /* disable interrupts */
+ CURRENT_THREAD_INFO(r9, r1)
+ lwz r9,TI_FLAGS(r9)
+- andi. r0,r9,_TIF_NEED_RESCHED
++ andi. r0,r9,_TIF_NEED_RESCHED_MASK
+ bne- do_resched
+ andi. r0,r9,_TIF_USER_WORK_MASK
+ beq restore_user
+diff -Nur linux-4.8.15.orig/arch/powerpc/kernel/entry_64.S linux-4.8.15/arch/powerpc/kernel/entry_64.S
+--- linux-4.8.15.orig/arch/powerpc/kernel/entry_64.S 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/powerpc/kernel/entry_64.S 2017-01-01 17:07:12.535201773 +0100
+@@ -657,7 +657,7 @@
+ bl restore_math
+ b restore
+ #endif
+-1: andi. r0,r4,_TIF_NEED_RESCHED
++1: andi. r0,r4,_TIF_NEED_RESCHED_MASK
+ beq 2f
+ bl restore_interrupts
+ SCHEDULE_USER
+@@ -719,10 +719,18 @@
+
+ #ifdef CONFIG_PREEMPT
+ /* Check if we need to preempt */
++ lwz r8,TI_PREEMPT(r9)
++ cmpwi 0,r8,0 /* if non-zero, just restore regs and return */
++ bne restore
+ andi. r0,r4,_TIF_NEED_RESCHED
++ bne+ check_count
++
++ andi. r0,r4,_TIF_NEED_RESCHED_LAZY
+ beq+ restore
++ lwz r8,TI_PREEMPT_LAZY(r9)
++
+ /* Check that preempt_count() == 0 and interrupts are enabled */
+- lwz r8,TI_PREEMPT(r9)
++check_count:
+ cmpwi cr1,r8,0
+ ld r0,SOFTE(r1)
+ cmpdi r0,0
+@@ -739,7 +747,7 @@
+ /* Re-test flags and eventually loop */
+ CURRENT_THREAD_INFO(r9, r1)
+ ld r4,TI_FLAGS(r9)
+- andi. r0,r4,_TIF_NEED_RESCHED
++ andi. r0,r4,_TIF_NEED_RESCHED_MASK
+ bne 1b
+
+ /*
+diff -Nur linux-4.8.15.orig/arch/powerpc/kernel/irq.c linux-4.8.15/arch/powerpc/kernel/irq.c
+--- linux-4.8.15.orig/arch/powerpc/kernel/irq.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/powerpc/kernel/irq.c 2017-01-01 17:07:12.539202039 +0100
+@@ -633,6 +633,7 @@
+ }
+ }
+
++#ifndef CONFIG_PREEMPT_RT_FULL
+ void do_softirq_own_stack(void)
+ {
+ struct thread_info *curtp, *irqtp;
+@@ -650,6 +651,7 @@
+ if (irqtp->flags)
+ set_bits(irqtp->flags, &curtp->flags);
+ }
++#endif
+
+ irq_hw_number_t virq_to_hw(unsigned int virq)
+ {
+diff -Nur linux-4.8.15.orig/arch/powerpc/kernel/misc_32.S linux-4.8.15/arch/powerpc/kernel/misc_32.S
+--- linux-4.8.15.orig/arch/powerpc/kernel/misc_32.S 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/powerpc/kernel/misc_32.S 2017-01-01 17:07:12.543202293 +0100
+@@ -40,6 +40,7 @@
+ * We store the saved ksp_limit in the unused part
+ * of the STACK_FRAME_OVERHEAD
+ */
++#ifndef CONFIG_PREEMPT_RT_FULL
+ _GLOBAL(call_do_softirq)
+ mflr r0
+ stw r0,4(r1)
+@@ -56,6 +57,7 @@
+ stw r10,THREAD+KSP_LIMIT(r2)
+ mtlr r0
+ blr
++#endif
+
+ /*
+ * void call_do_irq(struct pt_regs *regs, struct thread_info *irqtp);
+diff -Nur linux-4.8.15.orig/arch/powerpc/kernel/misc_64.S linux-4.8.15/arch/powerpc/kernel/misc_64.S
+--- linux-4.8.15.orig/arch/powerpc/kernel/misc_64.S 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/powerpc/kernel/misc_64.S 2017-01-01 17:07:12.543202293 +0100
+@@ -30,6 +30,7 @@
+
+ .text
+
++#ifndef CONFIG_PREEMPT_RT_FULL
+ _GLOBAL(call_do_softirq)
+ mflr r0
+ std r0,16(r1)
+@@ -40,6 +41,7 @@
+ ld r0,16(r1)
+ mtlr r0
+ blr
++#endif
+
+ _GLOBAL(call_do_irq)
+ mflr r0
+diff -Nur linux-4.8.15.orig/arch/powerpc/kvm/Kconfig linux-4.8.15/arch/powerpc/kvm/Kconfig
+--- linux-4.8.15.orig/arch/powerpc/kvm/Kconfig 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/powerpc/kvm/Kconfig 2017-01-01 17:07:12.587205132 +0100
+@@ -172,6 +172,7 @@
+ config KVM_MPIC
+ bool "KVM in-kernel MPIC emulation"
+ depends on KVM && E500
++ depends on !PREEMPT_RT_FULL
+ select HAVE_KVM_IRQCHIP
+ select HAVE_KVM_IRQFD
+ select HAVE_KVM_IRQ_ROUTING
+diff -Nur linux-4.8.15.orig/arch/powerpc/platforms/ps3/device-init.c linux-4.8.15/arch/powerpc/platforms/ps3/device-init.c
+--- linux-4.8.15.orig/arch/powerpc/platforms/ps3/device-init.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/powerpc/platforms/ps3/device-init.c 2017-01-01 17:07:12.623207443 +0100
+@@ -752,7 +752,7 @@
+ }
+ pr_debug("%s:%u: notification %s issued\n", __func__, __LINE__, op);
+
+- res = wait_event_interruptible(dev->done.wait,
++ res = swait_event_interruptible(dev->done.wait,
+ dev->done.done || kthread_should_stop());
+ if (kthread_should_stop())
+ res = -EINTR;
+diff -Nur linux-4.8.15.orig/arch/sh/kernel/irq.c linux-4.8.15/arch/sh/kernel/irq.c
+--- linux-4.8.15.orig/arch/sh/kernel/irq.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/sh/kernel/irq.c 2017-01-01 17:07:12.687211566 +0100
+@@ -147,6 +147,7 @@
+ hardirq_ctx[cpu] = NULL;
+ }
+
++#ifndef CONFIG_PREEMPT_RT_FULL
+ void do_softirq_own_stack(void)
+ {
+ struct thread_info *curctx;
+@@ -174,6 +175,7 @@
+ "r5", "r6", "r7", "r8", "r9", "r15", "t", "pr"
+ );
+ }
++#endif
+ #else
+ static inline void handle_one_irq(unsigned int irq)
+ {
+diff -Nur linux-4.8.15.orig/arch/sparc/Kconfig linux-4.8.15/arch/sparc/Kconfig
+--- linux-4.8.15.orig/arch/sparc/Kconfig 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/sparc/Kconfig 2017-01-01 17:07:12.723213881 +0100
+@@ -187,12 +187,10 @@
+ source kernel/Kconfig.hz
+
+ config RWSEM_GENERIC_SPINLOCK
+- bool
+- default y if SPARC32
++ def_bool PREEMPT_RT_FULL
+
+ config RWSEM_XCHGADD_ALGORITHM
+- bool
+- default y if SPARC64
++ def_bool !RWSEM_GENERIC_SPINLOCK && !PREEMPT_RT_FULL
+
+ config GENERIC_HWEIGHT
+ bool
+diff -Nur linux-4.8.15.orig/arch/sparc/kernel/irq_64.c linux-4.8.15/arch/sparc/kernel/irq_64.c
+--- linux-4.8.15.orig/arch/sparc/kernel/irq_64.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/sparc/kernel/irq_64.c 2017-01-01 17:07:12.763216468 +0100
+@@ -854,6 +854,7 @@
+ set_irq_regs(old_regs);
+ }
+
++#ifndef CONFIG_PREEMPT_RT_FULL
+ void do_softirq_own_stack(void)
+ {
+ void *orig_sp, *sp = softirq_stack[smp_processor_id()];
+@@ -868,6 +869,7 @@
+ __asm__ __volatile__("mov %0, %%sp"
+ : : "r" (orig_sp));
+ }
++#endif
+
+ #ifdef CONFIG_HOTPLUG_CPU
+ void fixup_irqs(void)
+diff -Nur linux-4.8.15.orig/arch/x86/crypto/aesni-intel_glue.c linux-4.8.15/arch/x86/crypto/aesni-intel_glue.c
+--- linux-4.8.15.orig/arch/x86/crypto/aesni-intel_glue.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/x86/crypto/aesni-intel_glue.c 2017-01-01 17:07:12.971229856 +0100
+@@ -372,14 +372,14 @@
+ err = blkcipher_walk_virt(desc, &walk);
+ desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
+
+- kernel_fpu_begin();
+ while ((nbytes = walk.nbytes)) {
++ kernel_fpu_begin();
+ aesni_ecb_enc(ctx, walk.dst.virt.addr, walk.src.virt.addr,
+- nbytes & AES_BLOCK_MASK);
++ nbytes & AES_BLOCK_MASK);
++ kernel_fpu_end();
+ nbytes &= AES_BLOCK_SIZE - 1;
+ err = blkcipher_walk_done(desc, &walk, nbytes);
+ }
+- kernel_fpu_end();
+
+ return err;
+ }
+@@ -396,14 +396,14 @@
+ err = blkcipher_walk_virt(desc, &walk);
+ desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
+
+- kernel_fpu_begin();
+ while ((nbytes = walk.nbytes)) {
++ kernel_fpu_begin();
+ aesni_ecb_dec(ctx, walk.dst.virt.addr, walk.src.virt.addr,
+ nbytes & AES_BLOCK_MASK);
++ kernel_fpu_end();
+ nbytes &= AES_BLOCK_SIZE - 1;
+ err = blkcipher_walk_done(desc, &walk, nbytes);
+ }
+- kernel_fpu_end();
+
+ return err;
+ }
+@@ -420,14 +420,14 @@
+ err = blkcipher_walk_virt(desc, &walk);
+ desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
+
+- kernel_fpu_begin();
+ while ((nbytes = walk.nbytes)) {
++ kernel_fpu_begin();
+ aesni_cbc_enc(ctx, walk.dst.virt.addr, walk.src.virt.addr,
+ nbytes & AES_BLOCK_MASK, walk.iv);
++ kernel_fpu_end();
+ nbytes &= AES_BLOCK_SIZE - 1;
+ err = blkcipher_walk_done(desc, &walk, nbytes);
+ }
+- kernel_fpu_end();
+
+ return err;
+ }
+@@ -444,14 +444,14 @@
+ err = blkcipher_walk_virt(desc, &walk);
+ desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
+
+- kernel_fpu_begin();
+ while ((nbytes = walk.nbytes)) {
++ kernel_fpu_begin();
+ aesni_cbc_dec(ctx, walk.dst.virt.addr, walk.src.virt.addr,
+ nbytes & AES_BLOCK_MASK, walk.iv);
++ kernel_fpu_end();
+ nbytes &= AES_BLOCK_SIZE - 1;
+ err = blkcipher_walk_done(desc, &walk, nbytes);
+ }
+- kernel_fpu_end();
+
+ return err;
+ }
+@@ -503,18 +503,20 @@
+ err = blkcipher_walk_virt_block(desc, &walk, AES_BLOCK_SIZE);
+ desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
+
+- kernel_fpu_begin();
+ while ((nbytes = walk.nbytes) >= AES_BLOCK_SIZE) {
++ kernel_fpu_begin();
+ aesni_ctr_enc_tfm(ctx, walk.dst.virt.addr, walk.src.virt.addr,
+ nbytes & AES_BLOCK_MASK, walk.iv);
++ kernel_fpu_end();
+ nbytes &= AES_BLOCK_SIZE - 1;
+ err = blkcipher_walk_done(desc, &walk, nbytes);
+ }
+ if (walk.nbytes) {
++ kernel_fpu_begin();
+ ctr_crypt_final(ctx, &walk);
++ kernel_fpu_end();
+ err = blkcipher_walk_done(desc, &walk, 0);
+ }
+- kernel_fpu_end();
+
+ return err;
+ }
+diff -Nur linux-4.8.15.orig/arch/x86/crypto/cast5_avx_glue.c linux-4.8.15/arch/x86/crypto/cast5_avx_glue.c
+--- linux-4.8.15.orig/arch/x86/crypto/cast5_avx_glue.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/x86/crypto/cast5_avx_glue.c 2017-01-01 17:07:12.979230370 +0100
+@@ -59,7 +59,7 @@
+ static int ecb_crypt(struct blkcipher_desc *desc, struct blkcipher_walk *walk,
+ bool enc)
+ {
+- bool fpu_enabled = false;
++ bool fpu_enabled;
+ struct cast5_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
+ const unsigned int bsize = CAST5_BLOCK_SIZE;
+ unsigned int nbytes;
+@@ -75,7 +75,7 @@
+ u8 *wsrc = walk->src.virt.addr;
+ u8 *wdst = walk->dst.virt.addr;
+
+- fpu_enabled = cast5_fpu_begin(fpu_enabled, nbytes);
++ fpu_enabled = cast5_fpu_begin(false, nbytes);
+
+ /* Process multi-block batch */
+ if (nbytes >= bsize * CAST5_PARALLEL_BLOCKS) {
+@@ -103,10 +103,9 @@
+ } while (nbytes >= bsize);
+
+ done:
++ cast5_fpu_end(fpu_enabled);
+ err = blkcipher_walk_done(desc, walk, nbytes);
+ }
+-
+- cast5_fpu_end(fpu_enabled);
+ return err;
+ }
+
+@@ -227,7 +226,7 @@
+ static int cbc_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
+ struct scatterlist *src, unsigned int nbytes)
+ {
+- bool fpu_enabled = false;
++ bool fpu_enabled;
+ struct blkcipher_walk walk;
+ int err;
+
+@@ -236,12 +235,11 @@
+ desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
+
+ while ((nbytes = walk.nbytes)) {
+- fpu_enabled = cast5_fpu_begin(fpu_enabled, nbytes);
++ fpu_enabled = cast5_fpu_begin(false, nbytes);
+ nbytes = __cbc_decrypt(desc, &walk);
++ cast5_fpu_end(fpu_enabled);
+ err = blkcipher_walk_done(desc, &walk, nbytes);
+ }
+-
+- cast5_fpu_end(fpu_enabled);
+ return err;
+ }
+
+@@ -311,7 +309,7 @@
+ static int ctr_crypt(struct blkcipher_desc *desc, struct scatterlist *dst,
+ struct scatterlist *src, unsigned int nbytes)
+ {
+- bool fpu_enabled = false;
++ bool fpu_enabled;
+ struct blkcipher_walk walk;
+ int err;
+
+@@ -320,13 +318,12 @@
+ desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
+
+ while ((nbytes = walk.nbytes) >= CAST5_BLOCK_SIZE) {
+- fpu_enabled = cast5_fpu_begin(fpu_enabled, nbytes);
++ fpu_enabled = cast5_fpu_begin(false, nbytes);
+ nbytes = __ctr_crypt(desc, &walk);
++ cast5_fpu_end(fpu_enabled);
+ err = blkcipher_walk_done(desc, &walk, nbytes);
+ }
+
+- cast5_fpu_end(fpu_enabled);
+-
+ if (walk.nbytes) {
+ ctr_crypt_final(desc, &walk);
+ err = blkcipher_walk_done(desc, &walk, 0);
+diff -Nur linux-4.8.15.orig/arch/x86/crypto/glue_helper.c linux-4.8.15/arch/x86/crypto/glue_helper.c
+--- linux-4.8.15.orig/arch/x86/crypto/glue_helper.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/x86/crypto/glue_helper.c 2017-01-01 17:07:12.983230644 +0100
+@@ -39,7 +39,7 @@
+ void *ctx = crypto_blkcipher_ctx(desc->tfm);
+ const unsigned int bsize = 128 / 8;
+ unsigned int nbytes, i, func_bytes;
+- bool fpu_enabled = false;
++ bool fpu_enabled;
+ int err;
+
+ err = blkcipher_walk_virt(desc, walk);
+@@ -49,7 +49,7 @@
+ u8 *wdst = walk->dst.virt.addr;
+
+ fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit,
+- desc, fpu_enabled, nbytes);
++ desc, false, nbytes);
+
+ for (i = 0; i < gctx->num_funcs; i++) {
+ func_bytes = bsize * gctx->funcs[i].num_blocks;
+@@ -71,10 +71,10 @@
+ }
+
+ done:
++ glue_fpu_end(fpu_enabled);
+ err = blkcipher_walk_done(desc, walk, nbytes);
+ }
+
+- glue_fpu_end(fpu_enabled);
+ return err;
+ }
+
+@@ -194,7 +194,7 @@
+ struct scatterlist *src, unsigned int nbytes)
+ {
+ const unsigned int bsize = 128 / 8;
+- bool fpu_enabled = false;
++ bool fpu_enabled;
+ struct blkcipher_walk walk;
+ int err;
+
+@@ -203,12 +203,12 @@
+
+ while ((nbytes = walk.nbytes)) {
+ fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit,
+- desc, fpu_enabled, nbytes);
++ desc, false, nbytes);
+ nbytes = __glue_cbc_decrypt_128bit(gctx, desc, &walk);
++ glue_fpu_end(fpu_enabled);
+ err = blkcipher_walk_done(desc, &walk, nbytes);
+ }
+
+- glue_fpu_end(fpu_enabled);
+ return err;
+ }
+ EXPORT_SYMBOL_GPL(glue_cbc_decrypt_128bit);
+@@ -277,7 +277,7 @@
+ struct scatterlist *src, unsigned int nbytes)
+ {
+ const unsigned int bsize = 128 / 8;
+- bool fpu_enabled = false;
++ bool fpu_enabled;
+ struct blkcipher_walk walk;
+ int err;
+
+@@ -286,13 +286,12 @@
+
+ while ((nbytes = walk.nbytes) >= bsize) {
+ fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit,
+- desc, fpu_enabled, nbytes);
++ desc, false, nbytes);
+ nbytes = __glue_ctr_crypt_128bit(gctx, desc, &walk);
++ glue_fpu_end(fpu_enabled);
+ err = blkcipher_walk_done(desc, &walk, nbytes);
+ }
+
+- glue_fpu_end(fpu_enabled);
+-
+ if (walk.nbytes) {
+ glue_ctr_crypt_final_128bit(
+ gctx->funcs[gctx->num_funcs - 1].fn_u.ctr, desc, &walk);
+@@ -347,7 +346,7 @@
+ void *tweak_ctx, void *crypt_ctx)
+ {
+ const unsigned int bsize = 128 / 8;
+- bool fpu_enabled = false;
++ bool fpu_enabled;
+ struct blkcipher_walk walk;
+ int err;
+
+@@ -360,21 +359,21 @@
+
+ /* set minimum length to bsize, for tweak_fn */
+ fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit,
+- desc, fpu_enabled,
++ desc, false,
+ nbytes < bsize ? bsize : nbytes);
+-
+ /* calculate first value of T */
+ tweak_fn(tweak_ctx, walk.iv, walk.iv);
++ glue_fpu_end(fpu_enabled);
+
+ while (nbytes) {
++ fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit,
++ desc, false, nbytes);
+ nbytes = __glue_xts_crypt_128bit(gctx, crypt_ctx, desc, &walk);
+
++ glue_fpu_end(fpu_enabled);
+ err = blkcipher_walk_done(desc, &walk, nbytes);
+ nbytes = walk.nbytes;
+ }
+-
+- glue_fpu_end(fpu_enabled);
+-
+ return err;
+ }
+ EXPORT_SYMBOL_GPL(glue_xts_crypt_128bit);
+diff -Nur linux-4.8.15.orig/arch/x86/entry/common.c linux-4.8.15/arch/x86/entry/common.c
+--- linux-4.8.15.orig/arch/x86/entry/common.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/x86/entry/common.c 2017-01-01 17:07:13.071236305 +0100
+@@ -136,7 +136,7 @@
+
+ #define EXIT_TO_USERMODE_LOOP_FLAGS \
+ (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_UPROBE | \
+- _TIF_NEED_RESCHED | _TIF_USER_RETURN_NOTIFY)
++ _TIF_NEED_RESCHED_MASK | _TIF_USER_RETURN_NOTIFY)
+
+ static void exit_to_usermode_loop(struct pt_regs *regs, u32 cached_flags)
+ {
+@@ -152,9 +152,16 @@
+ /* We have work to do. */
+ local_irq_enable();
+
+- if (cached_flags & _TIF_NEED_RESCHED)
++ if (cached_flags & _TIF_NEED_RESCHED_MASK)
+ schedule();
+
++#ifdef ARCH_RT_DELAYS_SIGNAL_SEND
++ if (unlikely(current->forced_info.si_signo)) {
++ struct task_struct *t = current;
++ force_sig_info(t->forced_info.si_signo, &t->forced_info, t);
++ t->forced_info.si_signo = 0;
++ }
++#endif
+ if (cached_flags & _TIF_UPROBE)
+ uprobe_notify_resume(regs);
+
+diff -Nur linux-4.8.15.orig/arch/x86/entry/entry_32.S linux-4.8.15/arch/x86/entry/entry_32.S
+--- linux-4.8.15.orig/arch/x86/entry/entry_32.S 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/x86/entry/entry_32.S 2017-01-01 17:07:13.071236305 +0100
+@@ -271,8 +271,25 @@
+ ENTRY(resume_kernel)
+ DISABLE_INTERRUPTS(CLBR_ANY)
+ need_resched:
++ # preempt count == 0 + NEED_RS set?
+ cmpl $0, PER_CPU_VAR(__preempt_count)
++#ifndef CONFIG_PREEMPT_LAZY
+ jnz restore_all
++#else
++ jz test_int_off
++
++ # atleast preempt count == 0 ?
++ cmpl $_PREEMPT_ENABLED,PER_CPU_VAR(__preempt_count)
++ jne restore_all
++
++ GET_THREAD_INFO(%ebp)
++ cmpl $0,TI_preempt_lazy_count(%ebp) # non-zero preempt_lazy_count ?
++ jnz restore_all
++
++ testl $_TIF_NEED_RESCHED_LAZY, TI_flags(%ebp)
++ jz restore_all
++test_int_off:
++#endif
+ testl $X86_EFLAGS_IF, PT_EFLAGS(%esp) # interrupts off (exception path) ?
+ jz restore_all
+ call preempt_schedule_irq
+diff -Nur linux-4.8.15.orig/arch/x86/entry/entry_64.S linux-4.8.15/arch/x86/entry/entry_64.S
+--- linux-4.8.15.orig/arch/x86/entry/entry_64.S 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/x86/entry/entry_64.S 2017-01-01 17:07:13.071236305 +0100
+@@ -512,7 +512,23 @@
+ bt $9, EFLAGS(%rsp) /* were interrupts off? */
+ jnc 1f
+ 0: cmpl $0, PER_CPU_VAR(__preempt_count)
++#ifndef CONFIG_PREEMPT_LAZY
+ jnz 1f
++#else
++ jz do_preempt_schedule_irq
++
++ # atleast preempt count == 0 ?
++ cmpl $_PREEMPT_ENABLED,PER_CPU_VAR(__preempt_count)
++ jnz 1f
++
++ GET_THREAD_INFO(%rcx)
++ cmpl $0, TI_preempt_lazy_count(%rcx)
++ jnz 1f
++
++ bt $TIF_NEED_RESCHED_LAZY,TI_flags(%rcx)
++ jnc 1f
++do_preempt_schedule_irq:
++#endif
+ call preempt_schedule_irq
+ jmp 0b
+ 1:
+@@ -817,6 +833,7 @@
+ jmp 2b
+ .previous
+
++#ifndef CONFIG_PREEMPT_RT_FULL
+ /* Call softirq on interrupt stack. Interrupts are off. */
+ ENTRY(do_softirq_own_stack)
+ pushq %rbp
+@@ -829,6 +846,7 @@
+ decl PER_CPU_VAR(irq_count)
+ ret
+ END(do_softirq_own_stack)
++#endif
+
+ #ifdef CONFIG_XEN
+ idtentry xen_hypervisor_callback xen_do_hypervisor_callback has_error_code=0
+diff -Nur linux-4.8.15.orig/arch/x86/include/asm/preempt.h linux-4.8.15/arch/x86/include/asm/preempt.h
+--- linux-4.8.15.orig/arch/x86/include/asm/preempt.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/x86/include/asm/preempt.h 2017-01-01 17:07:13.123239646 +0100
+@@ -79,17 +79,46 @@
+ * a decrement which hits zero means we have no preempt_count and should
+ * reschedule.
+ */
+-static __always_inline bool __preempt_count_dec_and_test(void)
++static __always_inline bool ____preempt_count_dec_and_test(void)
+ {
+ GEN_UNARY_RMWcc("decl", __preempt_count, __percpu_arg(0), e);
+ }
+
++static __always_inline bool __preempt_count_dec_and_test(void)
++{
++ if (____preempt_count_dec_and_test())
++ return true;
++#ifdef CONFIG_PREEMPT_LAZY
++ if (current_thread_info()->preempt_lazy_count)
++ return false;
++ return test_thread_flag(TIF_NEED_RESCHED_LAZY);
++#else
++ return false;
++#endif
++}
++
+ /*
+ * Returns true when we need to resched and can (barring IRQ state).
+ */
+ static __always_inline bool should_resched(int preempt_offset)
+ {
++#ifdef CONFIG_PREEMPT_LAZY
++ u32 tmp;
++
++ tmp = raw_cpu_read_4(__preempt_count);
++ if (tmp == preempt_offset)
++ return true;
++
++ /* preempt count == 0 ? */
++ tmp &= ~PREEMPT_NEED_RESCHED;
++ if (tmp)
++ return false;
++ if (current_thread_info()->preempt_lazy_count)
++ return false;
++ return test_thread_flag(TIF_NEED_RESCHED_LAZY);
++#else
+ return unlikely(raw_cpu_read_4(__preempt_count) == preempt_offset);
++#endif
+ }
+
+ #ifdef CONFIG_PREEMPT
+diff -Nur linux-4.8.15.orig/arch/x86/include/asm/signal.h linux-4.8.15/arch/x86/include/asm/signal.h
+--- linux-4.8.15.orig/arch/x86/include/asm/signal.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/x86/include/asm/signal.h 2017-01-01 17:07:13.123239646 +0100
+@@ -23,6 +23,19 @@
+ unsigned long sig[_NSIG_WORDS];
+ } sigset_t;
+
++/*
++ * Because some traps use the IST stack, we must keep preemption
++ * disabled while calling do_trap(), but do_trap() may call
++ * force_sig_info() which will grab the signal spin_locks for the
++ * task, which in PREEMPT_RT_FULL are mutexes. By defining
++ * ARCH_RT_DELAYS_SIGNAL_SEND the force_sig_info() will set
++ * TIF_NOTIFY_RESUME and set up the signal to be sent on exit of the
++ * trap.
++ */
++#if defined(CONFIG_PREEMPT_RT_FULL)
++#define ARCH_RT_DELAYS_SIGNAL_SEND
++#endif
++
+ #ifndef CONFIG_COMPAT
+ typedef sigset_t compat_sigset_t;
+ #endif
+diff -Nur linux-4.8.15.orig/arch/x86/include/asm/stackprotector.h linux-4.8.15/arch/x86/include/asm/stackprotector.h
+--- linux-4.8.15.orig/arch/x86/include/asm/stackprotector.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/x86/include/asm/stackprotector.h 2017-01-01 17:07:13.127239912 +0100
+@@ -59,7 +59,7 @@
+ */
+ static __always_inline void boot_init_stack_canary(void)
+ {
+- u64 canary;
++ u64 uninitialized_var(canary);
+ u64 tsc;
+
+ #ifdef CONFIG_X86_64
+@@ -70,8 +70,15 @@
+ * of randomness. The TSC only matters for very early init,
+ * there it already has some randomness on most systems. Later
+ * on during the bootup the random pool has true entropy too.
++ *
++ * For preempt-rt we need to weaken the randomness a bit, as
++ * we can't call into the random generator from atomic context
++ * due to locking constraints. We just leave canary
++ * uninitialized and use the TSC based randomness on top of it.
+ */
++#ifndef CONFIG_PREEMPT_RT_FULL
+ get_random_bytes(&canary, sizeof(canary));
++#endif
+ tsc = rdtsc();
+ canary += tsc + (tsc << 32UL);
+
+diff -Nur linux-4.8.15.orig/arch/x86/include/asm/thread_info.h linux-4.8.15/arch/x86/include/asm/thread_info.h
+--- linux-4.8.15.orig/arch/x86/include/asm/thread_info.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/x86/include/asm/thread_info.h 2017-01-01 17:07:13.127239912 +0100
+@@ -57,6 +57,8 @@
+ __u32 flags; /* low level flags */
+ __u32 status; /* thread synchronous flags */
+ __u32 cpu; /* current CPU */
++ int preempt_lazy_count; /* 0 => lazy preemptable
++ <0 => BUG */
+ };
+
+ #define INIT_THREAD_INFO(tsk) \
+@@ -73,6 +75,10 @@
+
+ #include <asm/asm-offsets.h>
+
++#define GET_THREAD_INFO(reg) \
++ _ASM_MOV PER_CPU_VAR(cpu_current_top_of_stack),reg ; \
++ _ASM_SUB $(THREAD_SIZE),reg ;
++
+ #endif
+
+ /*
+@@ -91,6 +97,7 @@
+ #define TIF_SYSCALL_EMU 6 /* syscall emulation active */
+ #define TIF_SYSCALL_AUDIT 7 /* syscall auditing active */
+ #define TIF_SECCOMP 8 /* secure computing */
++#define TIF_NEED_RESCHED_LAZY 9 /* lazy rescheduling necessary */
+ #define TIF_USER_RETURN_NOTIFY 11 /* notify kernel of userspace return */
+ #define TIF_UPROBE 12 /* breakpointed or singlestepping */
+ #define TIF_NOTSC 16 /* TSC is not accessible in userland */
+@@ -115,6 +122,7 @@
+ #define _TIF_SYSCALL_EMU (1 << TIF_SYSCALL_EMU)
+ #define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT)
+ #define _TIF_SECCOMP (1 << TIF_SECCOMP)
++#define _TIF_NEED_RESCHED_LAZY (1 << TIF_NEED_RESCHED_LAZY)
+ #define _TIF_USER_RETURN_NOTIFY (1 << TIF_USER_RETURN_NOTIFY)
+ #define _TIF_UPROBE (1 << TIF_UPROBE)
+ #define _TIF_NOTSC (1 << TIF_NOTSC)
+@@ -151,6 +159,8 @@
+ #define _TIF_WORK_CTXSW_PREV (_TIF_WORK_CTXSW|_TIF_USER_RETURN_NOTIFY)
+ #define _TIF_WORK_CTXSW_NEXT (_TIF_WORK_CTXSW)
+
++#define _TIF_NEED_RESCHED_MASK (_TIF_NEED_RESCHED | _TIF_NEED_RESCHED_LAZY)
++
+ #define STACK_WARN (THREAD_SIZE/8)
+
+ /*
+diff -Nur linux-4.8.15.orig/arch/x86/include/asm/uv/uv_bau.h linux-4.8.15/arch/x86/include/asm/uv/uv_bau.h
+--- linux-4.8.15.orig/arch/x86/include/asm/uv/uv_bau.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/x86/include/asm/uv/uv_bau.h 2017-01-01 17:07:13.127239912 +0100
+@@ -615,9 +615,9 @@
+ cycles_t send_message;
+ cycles_t period_end;
+ cycles_t period_time;
+- spinlock_t uvhub_lock;
+- spinlock_t queue_lock;
+- spinlock_t disable_lock;
++ raw_spinlock_t uvhub_lock;
++ raw_spinlock_t queue_lock;
++ raw_spinlock_t disable_lock;
+ /* tunables */
+ int max_concurr;
+ int max_concurr_const;
+@@ -776,15 +776,15 @@
+ * to be lowered below the current 'v'. atomic_add_unless can only stop
+ * on equal.
+ */
+-static inline int atomic_inc_unless_ge(spinlock_t *lock, atomic_t *v, int u)
++static inline int atomic_inc_unless_ge(raw_spinlock_t *lock, atomic_t *v, int u)
+ {
+- spin_lock(lock);
++ raw_spin_lock(lock);
+ if (atomic_read(v) >= u) {
+- spin_unlock(lock);
++ raw_spin_unlock(lock);
+ return 0;
+ }
+ atomic_inc(v);
+- spin_unlock(lock);
++ raw_spin_unlock(lock);
+ return 1;
+ }
+
+diff -Nur linux-4.8.15.orig/arch/x86/Kconfig linux-4.8.15/arch/x86/Kconfig
+--- linux-4.8.15.orig/arch/x86/Kconfig 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/x86/Kconfig 2017-01-01 17:07:12.915226253 +0100
+@@ -17,6 +17,7 @@
+ ### Arch settings
+ config X86
+ def_bool y
++ select HAVE_PREEMPT_LAZY
+ select ACPI_LEGACY_TABLES_LOOKUP if ACPI
+ select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI
+ select ANON_INODES
+@@ -231,8 +232,11 @@
+ def_bool y
+ depends on ISA_DMA_API
+
++config RWSEM_GENERIC_SPINLOCK
++ def_bool PREEMPT_RT_FULL
++
+ config RWSEM_XCHGADD_ALGORITHM
+- def_bool y
++ def_bool !RWSEM_GENERIC_SPINLOCK && !PREEMPT_RT_FULL
+
+ config GENERIC_CALIBRATE_DELAY
+ def_bool y
+@@ -885,7 +889,7 @@
+ config MAXSMP
+ bool "Enable Maximum number of SMP Processors and NUMA Nodes"
+ depends on X86_64 && SMP && DEBUG_KERNEL
+- select CPUMASK_OFFSTACK
++ select CPUMASK_OFFSTACK if !PREEMPT_RT_FULL
+ ---help---
+ Enable maximum number of CPUS and NUMA Nodes for this architecture.
+ If unsure, say N.
+diff -Nur linux-4.8.15.orig/arch/x86/kernel/acpi/boot.c linux-4.8.15/arch/x86/kernel/acpi/boot.c
+--- linux-4.8.15.orig/arch/x86/kernel/acpi/boot.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/x86/kernel/acpi/boot.c 2017-01-01 17:07:13.171242740 +0100
+@@ -87,7 +87,9 @@
+ * ->ioapic_mutex
+ * ->ioapic_lock
+ */
++#ifdef CONFIG_X86_IO_APIC
+ static DEFINE_MUTEX(acpi_ioapic_lock);
++#endif
+
+ /* --------------------------------------------------------------------------
+ Boot-time Configuration
+diff -Nur linux-4.8.15.orig/arch/x86/kernel/apic/io_apic.c linux-4.8.15/arch/x86/kernel/apic/io_apic.c
+--- linux-4.8.15.orig/arch/x86/kernel/apic/io_apic.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/x86/kernel/apic/io_apic.c 2017-01-01 17:07:13.263248666 +0100
+@@ -1712,7 +1712,8 @@
+ static inline bool ioapic_irqd_mask(struct irq_data *data)
+ {
+ /* If we are moving the irq we need to mask it */
+- if (unlikely(irqd_is_setaffinity_pending(data))) {
++ if (unlikely(irqd_is_setaffinity_pending(data) &&
++ !irqd_irq_inprogress(data))) {
+ mask_ioapic_irq(data);
+ return true;
+ }
+diff -Nur linux-4.8.15.orig/arch/x86/kernel/asm-offsets.c linux-4.8.15/arch/x86/kernel/asm-offsets.c
+--- linux-4.8.15.orig/arch/x86/kernel/asm-offsets.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/x86/kernel/asm-offsets.c 2017-01-01 17:07:13.279249693 +0100
+@@ -31,6 +31,7 @@
+ BLANK();
+ OFFSET(TI_flags, thread_info, flags);
+ OFFSET(TI_status, thread_info, status);
++ OFFSET(TI_preempt_lazy_count, thread_info, preempt_lazy_count);
+
+ BLANK();
+ OFFSET(TASK_addr_limit, task_struct, thread.addr_limit);
+@@ -88,4 +89,5 @@
+
+ BLANK();
+ DEFINE(PTREGS_SIZE, sizeof(struct pt_regs));
++ DEFINE(_PREEMPT_ENABLED, PREEMPT_ENABLED);
+ }
+diff -Nur linux-4.8.15.orig/arch/x86/kernel/cpu/mcheck/mce.c linux-4.8.15/arch/x86/kernel/cpu/mcheck/mce.c
+--- linux-4.8.15.orig/arch/x86/kernel/cpu/mcheck/mce.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/x86/kernel/cpu/mcheck/mce.c 2017-01-01 17:07:13.335253297 +0100
+@@ -41,6 +41,8 @@
+ #include <linux/debugfs.h>
+ #include <linux/irq_work.h>
+ #include <linux/export.h>
++#include <linux/jiffies.h>
++#include <linux/swork.h>
+
+ #include <asm/processor.h>
+ #include <asm/traps.h>
+@@ -1291,7 +1293,7 @@
+ static unsigned long check_interval = INITIAL_CHECK_INTERVAL;
+
+ static DEFINE_PER_CPU(unsigned long, mce_next_interval); /* in jiffies */
+-static DEFINE_PER_CPU(struct timer_list, mce_timer);
++static DEFINE_PER_CPU(struct hrtimer, mce_timer);
+
+ static unsigned long mce_adjust_timer_default(unsigned long interval)
+ {
+@@ -1300,32 +1302,18 @@
+
+ static unsigned long (*mce_adjust_timer)(unsigned long interval) = mce_adjust_timer_default;
+
+-static void __restart_timer(struct timer_list *t, unsigned long interval)
++static enum hrtimer_restart __restart_timer(struct hrtimer *timer, unsigned long interval)
+ {
+- unsigned long when = jiffies + interval;
+- unsigned long flags;
+-
+- local_irq_save(flags);
+-
+- if (timer_pending(t)) {
+- if (time_before(when, t->expires))
+- mod_timer(t, when);
+- } else {
+- t->expires = round_jiffies(when);
+- add_timer_on(t, smp_processor_id());
+- }
+-
+- local_irq_restore(flags);
++ if (!interval)
++ return HRTIMER_NORESTART;
++ hrtimer_forward_now(timer, ns_to_ktime(jiffies_to_nsecs(interval)));
++ return HRTIMER_RESTART;
+ }
+
+-static void mce_timer_fn(unsigned long data)
++static enum hrtimer_restart mce_timer_fn(struct hrtimer *timer)
+ {
+- struct timer_list *t = this_cpu_ptr(&mce_timer);
+- int cpu = smp_processor_id();
+ unsigned long iv;
+
+- WARN_ON(cpu != data);
+-
+ iv = __this_cpu_read(mce_next_interval);
+
+ if (mce_available(this_cpu_ptr(&cpu_info))) {
+@@ -1348,7 +1336,7 @@
+
+ done:
+ __this_cpu_write(mce_next_interval, iv);
+- __restart_timer(t, iv);
++ return __restart_timer(timer, iv);
+ }
+
+ /*
+@@ -1356,7 +1344,7 @@
+ */
+ void mce_timer_kick(unsigned long interval)
+ {
+- struct timer_list *t = this_cpu_ptr(&mce_timer);
++ struct hrtimer *t = this_cpu_ptr(&mce_timer);
+ unsigned long iv = __this_cpu_read(mce_next_interval);
+
+ __restart_timer(t, interval);
+@@ -1371,7 +1359,7 @@
+ int cpu;
+
+ for_each_online_cpu(cpu)
+- del_timer_sync(&per_cpu(mce_timer, cpu));
++ hrtimer_cancel(&per_cpu(mce_timer, cpu));
+ }
+
+ static void mce_do_trigger(struct work_struct *work)
+@@ -1381,6 +1369,56 @@
+
+ static DECLARE_WORK(mce_trigger_work, mce_do_trigger);
+
++static void __mce_notify_work(struct swork_event *event)
++{
++ /* Not more than two messages every minute */
++ static DEFINE_RATELIMIT_STATE(ratelimit, 60*HZ, 2);
++
++ /* wake processes polling /dev/mcelog */
++ wake_up_interruptible(&mce_chrdev_wait);
++
++ /*
++ * There is no risk of missing notifications because
++ * work_pending is always cleared before the function is
++ * executed.
++ */
++ if (mce_helper[0] && !work_pending(&mce_trigger_work))
++ schedule_work(&mce_trigger_work);
++
++ if (__ratelimit(&ratelimit))
++ pr_info(HW_ERR "Machine check events logged\n");
++}
++
++#ifdef CONFIG_PREEMPT_RT_FULL
++static bool notify_work_ready __read_mostly;
++static struct swork_event notify_work;
++
++static int mce_notify_work_init(void)
++{
++ int err;
++
++ err = swork_get();
++ if (err)
++ return err;
++
++ INIT_SWORK(&notify_work, __mce_notify_work);
++ notify_work_ready = true;
++ return 0;
++}
++
++static void mce_notify_work(void)
++{
++ if (notify_work_ready)
++ swork_queue(&notify_work);
++}
++#else
++static void mce_notify_work(void)
++{
++ __mce_notify_work(NULL);
++}
++static inline int mce_notify_work_init(void) { return 0; }
++#endif
++
+ /*
+ * Notify the user(s) about new machine check events.
+ * Can be called from interrupt context, but not from machine check/NMI
+@@ -1388,19 +1426,8 @@
+ */
+ int mce_notify_irq(void)
+ {
+- /* Not more than two messages every minute */
+- static DEFINE_RATELIMIT_STATE(ratelimit, 60*HZ, 2);
+-
+ if (test_and_clear_bit(0, &mce_need_notify)) {
+- /* wake processes polling /dev/mcelog */
+- wake_up_interruptible(&mce_chrdev_wait);
+-
+- if (mce_helper[0])
+- schedule_work(&mce_trigger_work);
+-
+- if (__ratelimit(&ratelimit))
+- pr_info(HW_ERR "Machine check events logged\n");
+-
++ mce_notify_work();
+ return 1;
+ }
+ return 0;
+@@ -1717,7 +1744,7 @@
+ }
+ }
+
+-static void mce_start_timer(unsigned int cpu, struct timer_list *t)
++static void mce_start_timer(unsigned int cpu, struct hrtimer *t)
+ {
+ unsigned long iv = check_interval * HZ;
+
+@@ -1726,16 +1753,17 @@
+
+ per_cpu(mce_next_interval, cpu) = iv;
+
+- t->expires = round_jiffies(jiffies + iv);
+- add_timer_on(t, cpu);
++ hrtimer_start_range_ns(t, ns_to_ktime(jiffies_to_usecs(iv) * 1000ULL),
++ 0, HRTIMER_MODE_REL_PINNED);
+ }
+
+ static void __mcheck_cpu_init_timer(void)
+ {
+- struct timer_list *t = this_cpu_ptr(&mce_timer);
++ struct hrtimer *t = this_cpu_ptr(&mce_timer);
+ unsigned int cpu = smp_processor_id();
+
+- setup_pinned_timer(t, mce_timer_fn, cpu);
++ hrtimer_init(t, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
++ t->function = mce_timer_fn;
+ mce_start_timer(cpu, t);
+ }
+
+@@ -2459,6 +2487,8 @@
+ if (!mce_available(raw_cpu_ptr(&cpu_info)))
+ return;
+
++ hrtimer_cancel(this_cpu_ptr(&mce_timer));
++
+ if (!(action & CPU_TASKS_FROZEN))
+ cmci_clear();
+
+@@ -2481,6 +2511,7 @@
+ if (b->init)
+ wrmsrl(msr_ops.ctl(i), b->ctl);
+ }
++ __mcheck_cpu_init_timer();
+ }
+
+ /* Get notified when a cpu comes on/off. Be hotplug friendly. */
+@@ -2488,7 +2519,6 @@
+ mce_cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu)
+ {
+ unsigned int cpu = (unsigned long)hcpu;
+- struct timer_list *t = &per_cpu(mce_timer, cpu);
+
+ switch (action & ~CPU_TASKS_FROZEN) {
+ case CPU_ONLINE:
+@@ -2508,11 +2538,9 @@
+ break;
+ case CPU_DOWN_PREPARE:
+ smp_call_function_single(cpu, mce_disable_cpu, &action, 1);
+- del_timer_sync(t);
+ break;
+ case CPU_DOWN_FAILED:
+ smp_call_function_single(cpu, mce_reenable_cpu, &action, 1);
+- mce_start_timer(cpu, t);
+ break;
+ }
+
+@@ -2551,6 +2579,10 @@
+ goto err_out;
+ }
+
++ err = mce_notify_work_init();
++ if (err)
++ goto err_out;
++
+ if (!zalloc_cpumask_var(&mce_device_initialized, GFP_KERNEL)) {
+ err = -ENOMEM;
+ goto err_out;
+diff -Nur linux-4.8.15.orig/arch/x86/kernel/dumpstack_32.c linux-4.8.15/arch/x86/kernel/dumpstack_32.c
+--- linux-4.8.15.orig/arch/x86/kernel/dumpstack_32.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/x86/kernel/dumpstack_32.c 2017-01-01 17:07:13.351254342 +0100
+@@ -42,7 +42,7 @@
+ unsigned long *stack, unsigned long bp,
+ const struct stacktrace_ops *ops, void *data)
+ {
+- const unsigned cpu = get_cpu();
++ const unsigned cpu = get_cpu_light();
+ int graph = 0;
+ u32 *prev_esp;
+
+@@ -84,7 +84,7 @@
+ break;
+ touch_nmi_watchdog();
+ }
+- put_cpu();
++ put_cpu_light();
+ }
+ EXPORT_SYMBOL(dump_trace);
+
+diff -Nur linux-4.8.15.orig/arch/x86/kernel/dumpstack_64.c linux-4.8.15/arch/x86/kernel/dumpstack_64.c
+--- linux-4.8.15.orig/arch/x86/kernel/dumpstack_64.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/x86/kernel/dumpstack_64.c 2017-01-01 17:07:13.351254342 +0100
+@@ -152,7 +152,7 @@
+ unsigned long *stack, unsigned long bp,
+ const struct stacktrace_ops *ops, void *data)
+ {
+- const unsigned cpu = get_cpu();
++ const unsigned cpu = get_cpu_light();
+ unsigned long *irq_stack = (unsigned long *)per_cpu(irq_stack_ptr, cpu);
+ unsigned long dummy;
+ unsigned used = 0;
+@@ -239,7 +239,7 @@
+ * This handles the process stack:
+ */
+ bp = ops->walk_stack(task, stack, bp, ops, data, NULL, &graph);
+- put_cpu();
++ put_cpu_light();
+ }
+ EXPORT_SYMBOL(dump_trace);
+
+@@ -253,7 +253,7 @@
+ int cpu;
+ int i;
+
+- preempt_disable();
++ migrate_disable();
+ cpu = smp_processor_id();
+
+ irq_stack_end = (unsigned long *)(per_cpu(irq_stack_ptr, cpu));
+@@ -299,7 +299,7 @@
+ stack++;
+ touch_nmi_watchdog();
+ }
+- preempt_enable();
++ migrate_enable();
+
+ pr_cont("\n");
+ show_trace_log_lvl(task, regs, sp, bp, log_lvl);
+diff -Nur linux-4.8.15.orig/arch/x86/kernel/irq_32.c linux-4.8.15/arch/x86/kernel/irq_32.c
+--- linux-4.8.15.orig/arch/x86/kernel/irq_32.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/x86/kernel/irq_32.c 2017-01-01 17:07:13.351254342 +0100
+@@ -127,6 +127,7 @@
+ cpu, per_cpu(hardirq_stack, cpu), per_cpu(softirq_stack, cpu));
+ }
+
++#ifndef CONFIG_PREEMPT_RT_FULL
+ void do_softirq_own_stack(void)
+ {
+ struct irq_stack *irqstk;
+@@ -143,6 +144,7 @@
+
+ call_on_stack(__do_softirq, isp);
+ }
++#endif
+
+ bool handle_irq(struct irq_desc *desc, struct pt_regs *regs)
+ {
+diff -Nur linux-4.8.15.orig/arch/x86/kernel/process_32.c linux-4.8.15/arch/x86/kernel/process_32.c
+--- linux-4.8.15.orig/arch/x86/kernel/process_32.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/x86/kernel/process_32.c 2017-01-01 17:07:13.359254847 +0100
+@@ -35,6 +35,7 @@
+ #include <linux/uaccess.h>
+ #include <linux/io.h>
+ #include <linux/kdebug.h>
++#include <linux/highmem.h>
+
+ #include <asm/pgtable.h>
+ #include <asm/ldt.h>
+@@ -210,6 +211,35 @@
+ }
+ EXPORT_SYMBOL_GPL(start_thread);
+
++#ifdef CONFIG_PREEMPT_RT_FULL
++static void switch_kmaps(struct task_struct *prev_p, struct task_struct *next_p)
++{
++ int i;
++
++ /*
++ * Clear @prev's kmap_atomic mappings
++ */
++ for (i = 0; i < prev_p->kmap_idx; i++) {
++ int idx = i + KM_TYPE_NR * smp_processor_id();
++ pte_t *ptep = kmap_pte - idx;
++
++ kpte_clear_flush(ptep, __fix_to_virt(FIX_KMAP_BEGIN + idx));
++ }
++ /*
++ * Restore @next_p's kmap_atomic mappings
++ */
++ for (i = 0; i < next_p->kmap_idx; i++) {
++ int idx = i + KM_TYPE_NR * smp_processor_id();
++
++ if (!pte_none(next_p->kmap_pte[i]))
++ set_pte(kmap_pte - idx, next_p->kmap_pte[i]);
++ }
++}
++#else
++static inline void
++switch_kmaps(struct task_struct *prev_p, struct task_struct *next_p) { }
++#endif
++
+
+ /*
+ * switch_to(x,y) should switch tasks from x to y.
+@@ -286,6 +316,8 @@
+ task_thread_info(next_p)->flags & _TIF_WORK_CTXSW_NEXT))
+ __switch_to_xtra(prev_p, next_p, tss);
+
++ switch_kmaps(prev_p, next_p);
++
+ /*
+ * Leave lazy mode, flushing any hypercalls made here.
+ * This must be done before restoring TLS segments so
+diff -Nur linux-4.8.15.orig/arch/x86/kvm/lapic.c linux-4.8.15/arch/x86/kvm/lapic.c
+--- linux-4.8.15.orig/arch/x86/kvm/lapic.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/x86/kvm/lapic.c 2017-01-01 17:07:13.379256138 +0100
+@@ -1938,6 +1938,7 @@
+ hrtimer_init(&apic->lapic_timer.timer, CLOCK_MONOTONIC,
+ HRTIMER_MODE_ABS_PINNED);
+ apic->lapic_timer.timer.function = apic_timer_fn;
++ apic->lapic_timer.timer.irqsafe = 1;
+
+ /*
+ * APIC is created enabled. This will prevent kvm_lapic_set_base from
+diff -Nur linux-4.8.15.orig/arch/x86/kvm/x86.c linux-4.8.15/arch/x86/kvm/x86.c
+--- linux-4.8.15.orig/arch/x86/kvm/x86.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/x86/kvm/x86.c 2017-01-01 17:07:13.415258465 +0100
+@@ -5877,6 +5877,13 @@
+ goto out;
+ }
+
++#ifdef CONFIG_PREEMPT_RT_FULL
++ if (!boot_cpu_has(X86_FEATURE_CONSTANT_TSC)) {
++ printk(KERN_ERR "RT requires X86_FEATURE_CONSTANT_TSC\n");
++ return -EOPNOTSUPP;
++ }
++#endif
++
+ r = kvm_mmu_module_init();
+ if (r)
+ goto out_free_percpu;
+diff -Nur linux-4.8.15.orig/arch/x86/mm/highmem_32.c linux-4.8.15/arch/x86/mm/highmem_32.c
+--- linux-4.8.15.orig/arch/x86/mm/highmem_32.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/x86/mm/highmem_32.c 2017-01-01 17:07:13.443260261 +0100
+@@ -32,10 +32,11 @@
+ */
+ void *kmap_atomic_prot(struct page *page, pgprot_t prot)
+ {
++ pte_t pte = mk_pte(page, prot);
+ unsigned long vaddr;
+ int idx, type;
+
+- preempt_disable();
++ preempt_disable_nort();
+ pagefault_disable();
+
+ if (!PageHighMem(page))
+@@ -45,7 +46,10 @@
+ idx = type + KM_TYPE_NR*smp_processor_id();
+ vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
+ BUG_ON(!pte_none(*(kmap_pte-idx)));
+- set_pte(kmap_pte-idx, mk_pte(page, prot));
++#ifdef CONFIG_PREEMPT_RT_FULL
++ current->kmap_pte[type] = pte;
++#endif
++ set_pte(kmap_pte-idx, pte);
+ arch_flush_lazy_mmu_mode();
+
+ return (void *)vaddr;
+@@ -88,6 +92,9 @@
+ * is a bad idea also, in case the page changes cacheability
+ * attributes or becomes a protected page in a hypervisor.
+ */
++#ifdef CONFIG_PREEMPT_RT_FULL
++ current->kmap_pte[type] = __pte(0);
++#endif
+ kpte_clear_flush(kmap_pte-idx, vaddr);
+ kmap_atomic_idx_pop();
+ arch_flush_lazy_mmu_mode();
+@@ -100,7 +107,7 @@
+ #endif
+
+ pagefault_enable();
+- preempt_enable();
++ preempt_enable_nort();
+ }
+ EXPORT_SYMBOL(__kunmap_atomic);
+
+diff -Nur linux-4.8.15.orig/arch/x86/mm/iomap_32.c linux-4.8.15/arch/x86/mm/iomap_32.c
+--- linux-4.8.15.orig/arch/x86/mm/iomap_32.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/x86/mm/iomap_32.c 2017-01-01 17:07:13.471262063 +0100
+@@ -56,6 +56,7 @@
+
+ void *kmap_atomic_prot_pfn(unsigned long pfn, pgprot_t prot)
+ {
++ pte_t pte = pfn_pte(pfn, prot);
+ unsigned long vaddr;
+ int idx, type;
+
+@@ -65,7 +66,12 @@
+ type = kmap_atomic_idx_push();
+ idx = type + KM_TYPE_NR * smp_processor_id();
+ vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
+- set_pte(kmap_pte - idx, pfn_pte(pfn, prot));
++ WARN_ON(!pte_none(*(kmap_pte - idx)));
++
++#ifdef CONFIG_PREEMPT_RT_FULL
++ current->kmap_pte[type] = pte;
++#endif
++ set_pte(kmap_pte - idx, pte);
+ arch_flush_lazy_mmu_mode();
+
+ return (void *)vaddr;
+@@ -113,6 +119,9 @@
+ * is a bad idea also, in case the page changes cacheability
+ * attributes or becomes a protected page in a hypervisor.
+ */
++#ifdef CONFIG_PREEMPT_RT_FULL
++ current->kmap_pte[type] = __pte(0);
++#endif
+ kpte_clear_flush(kmap_pte-idx, vaddr);
+ kmap_atomic_idx_pop();
+ }
+diff -Nur linux-4.8.15.orig/arch/x86/platform/uv/tlb_uv.c linux-4.8.15/arch/x86/platform/uv/tlb_uv.c
+--- linux-4.8.15.orig/arch/x86/platform/uv/tlb_uv.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/x86/platform/uv/tlb_uv.c 2017-01-01 17:07:13.575268756 +0100
+@@ -729,9 +729,9 @@
+
+ quiesce_local_uvhub(hmaster);
+
+- spin_lock(&hmaster->queue_lock);
++ raw_spin_lock(&hmaster->queue_lock);
+ reset_with_ipi(&bau_desc->distribution, bcp);
+- spin_unlock(&hmaster->queue_lock);
++ raw_spin_unlock(&hmaster->queue_lock);
+
+ end_uvhub_quiesce(hmaster);
+
+@@ -751,9 +751,9 @@
+
+ quiesce_local_uvhub(hmaster);
+
+- spin_lock(&hmaster->queue_lock);
++ raw_spin_lock(&hmaster->queue_lock);
+ reset_with_ipi(&bau_desc->distribution, bcp);
+- spin_unlock(&hmaster->queue_lock);
++ raw_spin_unlock(&hmaster->queue_lock);
+
+ end_uvhub_quiesce(hmaster);
+
+@@ -774,7 +774,7 @@
+ cycles_t tm1;
+
+ hmaster = bcp->uvhub_master;
+- spin_lock(&hmaster->disable_lock);
++ raw_spin_lock(&hmaster->disable_lock);
+ if (!bcp->baudisabled) {
+ stat->s_bau_disabled++;
+ tm1 = get_cycles();
+@@ -787,7 +787,7 @@
+ }
+ }
+ }
+- spin_unlock(&hmaster->disable_lock);
++ raw_spin_unlock(&hmaster->disable_lock);
+ }
+
+ static void count_max_concurr(int stat, struct bau_control *bcp,
+@@ -850,7 +850,7 @@
+ */
+ static void uv1_throttle(struct bau_control *hmaster, struct ptc_stats *stat)
+ {
+- spinlock_t *lock = &hmaster->uvhub_lock;
++ raw_spinlock_t *lock = &hmaster->uvhub_lock;
+ atomic_t *v;
+
+ v = &hmaster->active_descriptor_count;
+@@ -983,7 +983,7 @@
+ struct bau_control *hmaster;
+
+ hmaster = bcp->uvhub_master;
+- spin_lock(&hmaster->disable_lock);
++ raw_spin_lock(&hmaster->disable_lock);
+ if (bcp->baudisabled && (get_cycles() >= bcp->set_bau_on_time)) {
+ stat->s_bau_reenabled++;
+ for_each_present_cpu(tcpu) {
+@@ -995,10 +995,10 @@
+ tbcp->period_giveups = 0;
+ }
+ }
+- spin_unlock(&hmaster->disable_lock);
++ raw_spin_unlock(&hmaster->disable_lock);
+ return 0;
+ }
+- spin_unlock(&hmaster->disable_lock);
++ raw_spin_unlock(&hmaster->disable_lock);
+ return -1;
+ }
+
+@@ -1916,9 +1916,9 @@
+ bcp->cong_reps = congested_reps;
+ bcp->disabled_period = sec_2_cycles(disabled_period);
+ bcp->giveup_limit = giveup_limit;
+- spin_lock_init(&bcp->queue_lock);
+- spin_lock_init(&bcp->uvhub_lock);
+- spin_lock_init(&bcp->disable_lock);
++ raw_spin_lock_init(&bcp->queue_lock);
++ raw_spin_lock_init(&bcp->uvhub_lock);
++ raw_spin_lock_init(&bcp->disable_lock);
+ }
+ }
+
+diff -Nur linux-4.8.15.orig/arch/x86/platform/uv/uv_time.c linux-4.8.15/arch/x86/platform/uv/uv_time.c
+--- linux-4.8.15.orig/arch/x86/platform/uv/uv_time.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/arch/x86/platform/uv/uv_time.c 2017-01-01 17:07:13.575268756 +0100
+@@ -57,7 +57,7 @@
+
+ /* There is one of these allocated per node */
+ struct uv_rtc_timer_head {
+- spinlock_t lock;
++ raw_spinlock_t lock;
+ /* next cpu waiting for timer, local node relative: */
+ int next_cpu;
+ /* number of cpus on this node: */
+@@ -177,7 +177,7 @@
+ uv_rtc_deallocate_timers();
+ return -ENOMEM;
+ }
+- spin_lock_init(&head->lock);
++ raw_spin_lock_init(&head->lock);
+ head->ncpus = uv_blade_nr_possible_cpus(bid);
+ head->next_cpu = -1;
+ blade_info[bid] = head;
+@@ -231,7 +231,7 @@
+ unsigned long flags;
+ int next_cpu;
+
+- spin_lock_irqsave(&head->lock, flags);
++ raw_spin_lock_irqsave(&head->lock, flags);
+
+ next_cpu = head->next_cpu;
+ *t = expires;
+@@ -243,12 +243,12 @@
+ if (uv_setup_intr(cpu, expires)) {
+ *t = ULLONG_MAX;
+ uv_rtc_find_next_timer(head, pnode);
+- spin_unlock_irqrestore(&head->lock, flags);
++ raw_spin_unlock_irqrestore(&head->lock, flags);
+ return -ETIME;
+ }
+ }
+
+- spin_unlock_irqrestore(&head->lock, flags);
++ raw_spin_unlock_irqrestore(&head->lock, flags);
+ return 0;
+ }
+
+@@ -267,7 +267,7 @@
+ unsigned long flags;
+ int rc = 0;
+
+- spin_lock_irqsave(&head->lock, flags);
++ raw_spin_lock_irqsave(&head->lock, flags);
+
+ if ((head->next_cpu == bcpu && uv_read_rtc(NULL) >= *t) || force)
+ rc = 1;
+@@ -279,7 +279,7 @@
+ uv_rtc_find_next_timer(head, pnode);
+ }
+
+- spin_unlock_irqrestore(&head->lock, flags);
++ raw_spin_unlock_irqrestore(&head->lock, flags);
+
+ return rc;
+ }
+@@ -299,13 +299,18 @@
+ static cycle_t uv_read_rtc(struct clocksource *cs)
+ {
+ unsigned long offset;
++ cycle_t cycles;
+
++ preempt_disable();
+ if (uv_get_min_hub_revision_id() == 1)
+ offset = 0;
+ else
+ offset = (uv_blade_processor_id() * L1_CACHE_BYTES) % PAGE_SIZE;
+
+- return (cycle_t)uv_read_local_mmr(UVH_RTC | offset);
++ cycles = (cycle_t)uv_read_local_mmr(UVH_RTC | offset);
++ preempt_enable();
++
++ return cycles;
+ }
+
+ /*
+diff -Nur linux-4.8.15.orig/block/blk-core.c linux-4.8.15/block/blk-core.c
+--- linux-4.8.15.orig/block/blk-core.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/block/blk-core.c 2017-01-01 17:07:13.619271599 +0100
+@@ -125,6 +125,9 @@
+
+ INIT_LIST_HEAD(&rq->queuelist);
+ INIT_LIST_HEAD(&rq->timeout_list);
++#ifdef CONFIG_PREEMPT_RT_FULL
++ INIT_WORK(&rq->work, __blk_mq_complete_request_remote_work);
++#endif
+ rq->cpu = -1;
+ rq->q = q;
+ rq->__sector = (sector_t) -1;
+@@ -233,7 +236,7 @@
+ **/
+ void blk_start_queue(struct request_queue *q)
+ {
+- WARN_ON(!irqs_disabled());
++ WARN_ON_NONRT(!irqs_disabled());
+
+ queue_flag_clear(QUEUE_FLAG_STOPPED, q);
+ __blk_run_queue(q);
+@@ -659,7 +662,7 @@
+ if (nowait)
+ return -EBUSY;
+
+- ret = wait_event_interruptible(q->mq_freeze_wq,
++ ret = swait_event_interruptible(q->mq_freeze_wq,
+ !atomic_read(&q->mq_freeze_depth) ||
+ blk_queue_dying(q));
+ if (blk_queue_dying(q))
+@@ -679,7 +682,7 @@
+ struct request_queue *q =
+ container_of(ref, struct request_queue, q_usage_counter);
+
+- wake_up_all(&q->mq_freeze_wq);
++ swake_up_all(&q->mq_freeze_wq);
+ }
+
+ static void blk_rq_timed_out_timer(unsigned long data)
+@@ -748,7 +751,7 @@
+ q->bypass_depth = 1;
+ __set_bit(QUEUE_FLAG_BYPASS, &q->queue_flags);
+
+- init_waitqueue_head(&q->mq_freeze_wq);
++ init_swait_queue_head(&q->mq_freeze_wq);
+
+ /*
+ * Init percpu_ref in atomic mode so that it's faster to shutdown.
+@@ -3171,7 +3174,7 @@
+ blk_run_queue_async(q);
+ else
+ __blk_run_queue(q);
+- spin_unlock(q->queue_lock);
++ spin_unlock_irq(q->queue_lock);
+ }
+
+ static void flush_plug_callbacks(struct blk_plug *plug, bool from_schedule)
+@@ -3219,7 +3222,6 @@
+ void blk_flush_plug_list(struct blk_plug *plug, bool from_schedule)
+ {
+ struct request_queue *q;
+- unsigned long flags;
+ struct request *rq;
+ LIST_HEAD(list);
+ unsigned int depth;
+@@ -3239,11 +3241,6 @@
+ q = NULL;
+ depth = 0;
+
+- /*
+- * Save and disable interrupts here, to avoid doing it for every
+- * queue lock we have to take.
+- */
+- local_irq_save(flags);
+ while (!list_empty(&list)) {
+ rq = list_entry_rq(list.next);
+ list_del_init(&rq->queuelist);
+@@ -3256,7 +3253,7 @@
+ queue_unplugged(q, depth, from_schedule);
+ q = rq->q;
+ depth = 0;
+- spin_lock(q->queue_lock);
++ spin_lock_irq(q->queue_lock);
+ }
+
+ /*
+@@ -3283,8 +3280,6 @@
+ */
+ if (q)
+ queue_unplugged(q, depth, from_schedule);
+-
+- local_irq_restore(flags);
+ }
+
+ void blk_finish_plug(struct blk_plug *plug)
+diff -Nur linux-4.8.15.orig/block/blk-ioc.c linux-4.8.15/block/blk-ioc.c
+--- linux-4.8.15.orig/block/blk-ioc.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/block/blk-ioc.c 2017-01-01 17:07:13.619271599 +0100
+@@ -7,6 +7,7 @@
+ #include <linux/bio.h>
+ #include <linux/blkdev.h>
+ #include <linux/slab.h>
++#include <linux/delay.h>
+
+ #include "blk.h"
+
+@@ -109,7 +110,7 @@
+ spin_unlock(q->queue_lock);
+ } else {
+ spin_unlock_irqrestore(&ioc->lock, flags);
+- cpu_relax();
++ cpu_chill();
+ spin_lock_irqsave_nested(&ioc->lock, flags, 1);
+ }
+ }
+@@ -187,7 +188,7 @@
+ spin_unlock(icq->q->queue_lock);
+ } else {
+ spin_unlock_irqrestore(&ioc->lock, flags);
+- cpu_relax();
++ cpu_chill();
+ goto retry;
+ }
+ }
+diff -Nur linux-4.8.15.orig/block/blk-mq.c linux-4.8.15/block/blk-mq.c
+--- linux-4.8.15.orig/block/blk-mq.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/block/blk-mq.c 2017-01-01 17:07:13.623271855 +0100
+@@ -92,7 +92,7 @@
+
+ static void blk_mq_freeze_queue_wait(struct request_queue *q)
+ {
+- wait_event(q->mq_freeze_wq, percpu_ref_is_zero(&q->q_usage_counter));
++ swait_event(q->mq_freeze_wq, percpu_ref_is_zero(&q->q_usage_counter));
+ }
+
+ /*
+@@ -130,7 +130,7 @@
+ WARN_ON_ONCE(freeze_depth < 0);
+ if (!freeze_depth) {
+ percpu_ref_reinit(&q->q_usage_counter);
+- wake_up_all(&q->mq_freeze_wq);
++ swake_up_all(&q->mq_freeze_wq);
+ }
+ }
+ EXPORT_SYMBOL_GPL(blk_mq_unfreeze_queue);
+@@ -149,7 +149,7 @@
+ * dying, we need to ensure that processes currently waiting on
+ * the queue are notified as well.
+ */
+- wake_up_all(&q->mq_freeze_wq);
++ swake_up_all(&q->mq_freeze_wq);
+ }
+
+ bool blk_mq_can_queue(struct blk_mq_hw_ctx *hctx)
+@@ -197,6 +197,9 @@
+ rq->resid_len = 0;
+ rq->sense = NULL;
+
++#ifdef CONFIG_PREEMPT_RT_FULL
++ INIT_WORK(&rq->work, __blk_mq_complete_request_remote_work);
++#endif
+ INIT_LIST_HEAD(&rq->timeout_list);
+ rq->timeout = 0;
+
+@@ -379,6 +382,17 @@
+ }
+ EXPORT_SYMBOL(blk_mq_end_request);
+
++#ifdef CONFIG_PREEMPT_RT_FULL
++
++void __blk_mq_complete_request_remote_work(struct work_struct *work)
++{
++ struct request *rq = container_of(work, struct request, work);
++
++ rq->q->softirq_done_fn(rq);
++}
++
++#else
++
+ static void __blk_mq_complete_request_remote(void *data)
+ {
+ struct request *rq = data;
+@@ -386,6 +400,8 @@
+ rq->q->softirq_done_fn(rq);
+ }
+
++#endif
++
+ static void blk_mq_ipi_complete_request(struct request *rq)
+ {
+ struct blk_mq_ctx *ctx = rq->mq_ctx;
+@@ -397,19 +413,23 @@
+ return;
+ }
+
+- cpu = get_cpu();
++ cpu = get_cpu_light();
+ if (!test_bit(QUEUE_FLAG_SAME_FORCE, &rq->q->queue_flags))
+ shared = cpus_share_cache(cpu, ctx->cpu);
+
+ if (cpu != ctx->cpu && !shared && cpu_online(ctx->cpu)) {
++#ifdef CONFIG_PREEMPT_RT_FULL
++ schedule_work_on(ctx->cpu, &rq->work);
++#else
+ rq->csd.func = __blk_mq_complete_request_remote;
+ rq->csd.info = rq;
+ rq->csd.flags = 0;
+ smp_call_function_single_async(ctx->cpu, &rq->csd);
++#endif
+ } else {
+ rq->q->softirq_done_fn(rq);
+ }
+- put_cpu();
++ put_cpu_light();
+ }
+
+ static void __blk_mq_complete_request(struct request *rq)
+@@ -938,14 +958,14 @@
+ return;
+
+ if (!async) {
+- int cpu = get_cpu();
++ int cpu = get_cpu_light();
+ if (cpumask_test_cpu(cpu, hctx->cpumask)) {
+ __blk_mq_run_hw_queue(hctx);
+- put_cpu();
++ put_cpu_light();
+ return;
+ }
+
+- put_cpu();
++ put_cpu_light();
+ }
+
+ kblockd_schedule_delayed_work_on(blk_mq_hctx_next_cpu(hctx),
+@@ -1667,7 +1687,7 @@
+ {
+ struct blk_mq_hw_ctx *hctx = data;
+
+- if (action == CPU_DEAD || action == CPU_DEAD_FROZEN)
++ if (action == CPU_POST_DEAD)
+ return blk_mq_hctx_cpu_offline(hctx, cpu);
+
+ /*
+diff -Nur linux-4.8.15.orig/block/blk-mq-cpu.c linux-4.8.15/block/blk-mq-cpu.c
+--- linux-4.8.15.orig/block/blk-mq-cpu.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/block/blk-mq-cpu.c 2017-01-01 17:07:13.623271855 +0100
+@@ -16,7 +16,7 @@
+ #include "blk-mq.h"
+
+ static LIST_HEAD(blk_mq_cpu_notify_list);
+-static DEFINE_RAW_SPINLOCK(blk_mq_cpu_notify_lock);
++static DEFINE_SPINLOCK(blk_mq_cpu_notify_lock);
+
+ static int blk_mq_main_cpu_notify(struct notifier_block *self,
+ unsigned long action, void *hcpu)
+@@ -25,7 +25,10 @@
+ struct blk_mq_cpu_notifier *notify;
+ int ret = NOTIFY_OK;
+
+- raw_spin_lock(&blk_mq_cpu_notify_lock);
++ if (action != CPU_POST_DEAD)
++ return NOTIFY_OK;
++
++ spin_lock(&blk_mq_cpu_notify_lock);
+
+ list_for_each_entry(notify, &blk_mq_cpu_notify_list, list) {
+ ret = notify->notify(notify->data, action, cpu);
+@@ -33,7 +36,7 @@
+ break;
+ }
+
+- raw_spin_unlock(&blk_mq_cpu_notify_lock);
++ spin_unlock(&blk_mq_cpu_notify_lock);
+ return ret;
+ }
+
+@@ -41,16 +44,16 @@
+ {
+ BUG_ON(!notifier->notify);
+
+- raw_spin_lock(&blk_mq_cpu_notify_lock);
++ spin_lock(&blk_mq_cpu_notify_lock);
+ list_add_tail(&notifier->list, &blk_mq_cpu_notify_list);
+- raw_spin_unlock(&blk_mq_cpu_notify_lock);
++ spin_unlock(&blk_mq_cpu_notify_lock);
+ }
+
+ void blk_mq_unregister_cpu_notifier(struct blk_mq_cpu_notifier *notifier)
+ {
+- raw_spin_lock(&blk_mq_cpu_notify_lock);
++ spin_lock(&blk_mq_cpu_notify_lock);
+ list_del(&notifier->list);
+- raw_spin_unlock(&blk_mq_cpu_notify_lock);
++ spin_unlock(&blk_mq_cpu_notify_lock);
+ }
+
+ void blk_mq_init_cpu_notifier(struct blk_mq_cpu_notifier *notifier,
+diff -Nur linux-4.8.15.orig/block/blk-mq.h linux-4.8.15/block/blk-mq.h
+--- linux-4.8.15.orig/block/blk-mq.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/block/blk-mq.h 2017-01-01 17:07:13.627272112 +0100
+@@ -86,12 +86,12 @@
+ */
+ static inline struct blk_mq_ctx *blk_mq_get_ctx(struct request_queue *q)
+ {
+- return __blk_mq_get_ctx(q, get_cpu());
++ return __blk_mq_get_ctx(q, get_cpu_light());
+ }
+
+ static inline void blk_mq_put_ctx(struct blk_mq_ctx *ctx)
+ {
+- put_cpu();
++ put_cpu_light();
+ }
+
+ struct blk_mq_alloc_data {
+diff -Nur linux-4.8.15.orig/block/blk-softirq.c linux-4.8.15/block/blk-softirq.c
+--- linux-4.8.15.orig/block/blk-softirq.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/block/blk-softirq.c 2017-01-01 17:07:13.627272112 +0100
+@@ -51,6 +51,7 @@
+ raise_softirq_irqoff(BLOCK_SOFTIRQ);
+
+ local_irq_restore(flags);
++ preempt_check_resched_rt();
+ }
+
+ /*
+@@ -93,6 +94,7 @@
+ this_cpu_ptr(&blk_cpu_done));
+ raise_softirq_irqoff(BLOCK_SOFTIRQ);
+ local_irq_enable();
++ preempt_check_resched_rt();
+ }
+
+ return NOTIFY_OK;
+@@ -150,6 +152,7 @@
+ goto do_local;
+
+ local_irq_restore(flags);
++ preempt_check_resched_rt();
+ }
+
+ /**
+diff -Nur linux-4.8.15.orig/block/bounce.c linux-4.8.15/block/bounce.c
+--- linux-4.8.15.orig/block/bounce.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/block/bounce.c 2017-01-01 17:07:13.627272112 +0100
+@@ -55,11 +55,11 @@
+ unsigned long flags;
+ unsigned char *vto;
+
+- local_irq_save(flags);
++ local_irq_save_nort(flags);
+ vto = kmap_atomic(to->bv_page);
+ memcpy(vto + to->bv_offset, vfrom, to->bv_len);
+ kunmap_atomic(vto);
+- local_irq_restore(flags);
++ local_irq_restore_nort(flags);
+ }
+
+ #else /* CONFIG_HIGHMEM */
+diff -Nur linux-4.8.15.orig/crypto/algapi.c linux-4.8.15/crypto/algapi.c
+--- linux-4.8.15.orig/crypto/algapi.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/crypto/algapi.c 2017-01-01 17:07:13.671274944 +0100
+@@ -718,13 +718,13 @@
+
+ int crypto_register_notifier(struct notifier_block *nb)
+ {
+- return blocking_notifier_chain_register(&crypto_chain, nb);
++ return srcu_notifier_chain_register(&crypto_chain, nb);
+ }
+ EXPORT_SYMBOL_GPL(crypto_register_notifier);
+
+ int crypto_unregister_notifier(struct notifier_block *nb)
+ {
+- return blocking_notifier_chain_unregister(&crypto_chain, nb);
++ return srcu_notifier_chain_unregister(&crypto_chain, nb);
+ }
+ EXPORT_SYMBOL_GPL(crypto_unregister_notifier);
+
+diff -Nur linux-4.8.15.orig/crypto/api.c linux-4.8.15/crypto/api.c
+--- linux-4.8.15.orig/crypto/api.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/crypto/api.c 2017-01-01 17:07:13.671274944 +0100
+@@ -31,7 +31,7 @@
+ DECLARE_RWSEM(crypto_alg_sem);
+ EXPORT_SYMBOL_GPL(crypto_alg_sem);
+
+-BLOCKING_NOTIFIER_HEAD(crypto_chain);
++SRCU_NOTIFIER_HEAD(crypto_chain);
+ EXPORT_SYMBOL_GPL(crypto_chain);
+
+ static struct crypto_alg *crypto_larval_wait(struct crypto_alg *alg);
+@@ -236,10 +236,10 @@
+ {
+ int ok;
+
+- ok = blocking_notifier_call_chain(&crypto_chain, val, v);
++ ok = srcu_notifier_call_chain(&crypto_chain, val, v);
+ if (ok == NOTIFY_DONE) {
+ request_module("cryptomgr");
+- ok = blocking_notifier_call_chain(&crypto_chain, val, v);
++ ok = srcu_notifier_call_chain(&crypto_chain, val, v);
+ }
+
+ return ok;
+diff -Nur linux-4.8.15.orig/crypto/internal.h linux-4.8.15/crypto/internal.h
+--- linux-4.8.15.orig/crypto/internal.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/crypto/internal.h 2017-01-01 17:07:13.675275210 +0100
+@@ -47,7 +47,7 @@
+
+ extern struct list_head crypto_alg_list;
+ extern struct rw_semaphore crypto_alg_sem;
+-extern struct blocking_notifier_head crypto_chain;
++extern struct srcu_notifier_head crypto_chain;
+
+ #ifdef CONFIG_PROC_FS
+ void __init crypto_init_proc(void);
+@@ -146,7 +146,7 @@
+
+ static inline void crypto_notify(unsigned long val, void *v)
+ {
+- blocking_notifier_call_chain(&crypto_chain, val, v);
++ srcu_notifier_call_chain(&crypto_chain, val, v);
+ }
+
+ #endif /* _CRYPTO_INTERNAL_H */
+diff -Nur linux-4.8.15.orig/Documentation/hwlat_detector.txt linux-4.8.15/Documentation/hwlat_detector.txt
+--- linux-4.8.15.orig/Documentation/hwlat_detector.txt 1970-01-01 01:00:00.000000000 +0100
++++ linux-4.8.15/Documentation/hwlat_detector.txt 2017-01-01 17:07:11.319123458 +0100
+@@ -0,0 +1,64 @@
++Introduction:
++-------------
++
++The module hwlat_detector is a special purpose kernel module that is used to
++detect large system latencies induced by the behavior of certain underlying
++hardware or firmware, independent of Linux itself. The code was developed
++originally to detect SMIs (System Management Interrupts) on x86 systems,
++however there is nothing x86 specific about this patchset. It was
++originally written for use by the "RT" patch since the Real Time
++kernel is highly latency sensitive.
++
++SMIs are usually not serviced by the Linux kernel, which typically does not
++even know that they are occuring. SMIs are instead are set up by BIOS code
++and are serviced by BIOS code, usually for "critical" events such as
++management of thermal sensors and fans. Sometimes though, SMIs are used for
++other tasks and those tasks can spend an inordinate amount of time in the
++handler (sometimes measured in milliseconds). Obviously this is a problem if
++you are trying to keep event service latencies down in the microsecond range.
++
++The hardware latency detector works by hogging all of the cpus for configurable
++amounts of time (by calling stop_machine()), polling the CPU Time Stamp Counter
++for some period, then looking for gaps in the TSC data. Any gap indicates a
++time when the polling was interrupted and since the machine is stopped and
++interrupts turned off the only thing that could do that would be an SMI.
++
++Note that the SMI detector should *NEVER* be used in a production environment.
++It is intended to be run manually to determine if the hardware platform has a
++problem with long system firmware service routines.
++
++Usage:
++------
++
++Loading the module hwlat_detector passing the parameter "enabled=1" (or by
++setting the "enable" entry in "hwlat_detector" debugfs toggled on) is the only
++step required to start the hwlat_detector. It is possible to redefine the
++threshold in microseconds (us) above which latency spikes will be taken
++into account (parameter "threshold=").
++
++Example:
++
++ # modprobe hwlat_detector enabled=1 threshold=100
++
++After the module is loaded, it creates a directory named "hwlat_detector" under
++the debugfs mountpoint, "/debug/hwlat_detector" for this text. It is necessary
++to have debugfs mounted, which might be on /sys/debug on your system.
++
++The /debug/hwlat_detector interface contains the following files:
++
++count - number of latency spikes observed since last reset
++enable - a global enable/disable toggle (0/1), resets count
++max - maximum hardware latency actually observed (usecs)
++sample - a pipe from which to read current raw sample data
++ in the format <timestamp> <latency observed usecs>
++ (can be opened O_NONBLOCK for a single sample)
++threshold - minimum latency value to be considered (usecs)
++width - time period to sample with CPUs held (usecs)
++ must be less than the total window size (enforced)
++window - total period of sampling, width being inside (usecs)
++
++By default we will set width to 500,000 and window to 1,000,000, meaning that
++we will sample every 1,000,000 usecs (1s) for 500,000 usecs (0.5s). If we
++observe any latencies that exceed the threshold (initially 100 usecs),
++then we write to a global sample ring buffer of 8K samples, which is
++consumed by reading from the "sample" (pipe) debugfs file interface.
+diff -Nur linux-4.8.15.orig/Documentation/sysrq.txt linux-4.8.15/Documentation/sysrq.txt
+--- linux-4.8.15.orig/Documentation/sysrq.txt 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/Documentation/sysrq.txt 2017-01-01 17:07:11.331124221 +0100
+@@ -59,10 +59,17 @@
+ On other - If you know of the key combos for other architectures, please
+ let me know so I can add them to this section.
+
+-On all - write a character to /proc/sysrq-trigger. e.g.:
+-
++On all - write a character to /proc/sysrq-trigger, e.g.:
+ echo t > /proc/sysrq-trigger
+
++On all - Enable network SysRq by writing a cookie to icmp_echo_sysrq, e.g.
++ echo 0x01020304 >/proc/sys/net/ipv4/icmp_echo_sysrq
++ Send an ICMP echo request with this pattern plus the particular
++ SysRq command key. Example:
++ # ping -c1 -s57 -p0102030468
++ will trigger the SysRq-H (help) command.
++
++
+ * What are the 'command' keys?
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ 'b' - Will immediately reboot the system without syncing or unmounting
+diff -Nur linux-4.8.15.orig/Documentation/trace/histograms.txt linux-4.8.15/Documentation/trace/histograms.txt
+--- linux-4.8.15.orig/Documentation/trace/histograms.txt 1970-01-01 01:00:00.000000000 +0100
++++ linux-4.8.15/Documentation/trace/histograms.txt 2017-01-01 17:07:11.399128611 +0100
+@@ -0,0 +1,186 @@
++ Using the Linux Kernel Latency Histograms
++
++
++This document gives a short explanation how to enable, configure and use
++latency histograms. Latency histograms are primarily relevant in the
++context of real-time enabled kernels (CONFIG_PREEMPT/CONFIG_PREEMPT_RT)
++and are used in the quality management of the Linux real-time
++capabilities.
++
++
++* Purpose of latency histograms
++
++A latency histogram continuously accumulates the frequencies of latency
++data. There are two types of histograms
++- potential sources of latencies
++- effective latencies
++
++
++* Potential sources of latencies
++
++Potential sources of latencies are code segments where interrupts,
++preemption or both are disabled (aka critical sections). To create
++histograms of potential sources of latency, the kernel stores the time
++stamp at the start of a critical section, determines the time elapsed
++when the end of the section is reached, and increments the frequency
++counter of that latency value - irrespective of whether any concurrently
++running process is affected by latency or not.
++- Configuration items (in the Kernel hacking/Tracers submenu)
++ CONFIG_INTERRUPT_OFF_LATENCY
++ CONFIG_PREEMPT_OFF_LATENCY
++
++
++* Effective latencies
++
++Effective latencies are actually occuring during wakeup of a process. To
++determine effective latencies, the kernel stores the time stamp when a
++process is scheduled to be woken up, and determines the duration of the
++wakeup time shortly before control is passed over to this process. Note
++that the apparent latency in user space may be somewhat longer, since the
++process may be interrupted after control is passed over to it but before
++the execution in user space takes place. Simply measuring the interval
++between enqueuing and wakeup may also not appropriate in cases when a
++process is scheduled as a result of a timer expiration. The timer may have
++missed its deadline, e.g. due to disabled interrupts, but this latency
++would not be registered. Therefore, the offsets of missed timers are
++recorded in a separate histogram. If both wakeup latency and missed timer
++offsets are configured and enabled, a third histogram may be enabled that
++records the overall latency as a sum of the timer latency, if any, and the
++wakeup latency. This histogram is called "timerandwakeup".
++- Configuration items (in the Kernel hacking/Tracers submenu)
++ CONFIG_WAKEUP_LATENCY
++ CONFIG_MISSED_TIMER_OFSETS
++
++
++* Usage
++
++The interface to the administration of the latency histograms is located
++in the debugfs file system. To mount it, either enter
++
++mount -t sysfs nodev /sys
++mount -t debugfs nodev /sys/kernel/debug
++
++from shell command line level, or add
++
++nodev /sys sysfs defaults 0 0
++nodev /sys/kernel/debug debugfs defaults 0 0
++
++to the file /etc/fstab. All latency histogram related files are then
++available in the directory /sys/kernel/debug/tracing/latency_hist. A
++particular histogram type is enabled by writing non-zero to the related
++variable in the /sys/kernel/debug/tracing/latency_hist/enable directory.
++Select "preemptirqsoff" for the histograms of potential sources of
++latencies and "wakeup" for histograms of effective latencies etc. The
++histogram data - one per CPU - are available in the files
++
++/sys/kernel/debug/tracing/latency_hist/preemptoff/CPUx
++/sys/kernel/debug/tracing/latency_hist/irqsoff/CPUx
++/sys/kernel/debug/tracing/latency_hist/preemptirqsoff/CPUx
++/sys/kernel/debug/tracing/latency_hist/wakeup/CPUx
++/sys/kernel/debug/tracing/latency_hist/wakeup/sharedprio/CPUx
++/sys/kernel/debug/tracing/latency_hist/missed_timer_offsets/CPUx
++/sys/kernel/debug/tracing/latency_hist/timerandwakeup/CPUx
++
++The histograms are reset by writing non-zero to the file "reset" in a
++particular latency directory. To reset all latency data, use
++
++#!/bin/sh
++
++TRACINGDIR=/sys/kernel/debug/tracing
++HISTDIR=$TRACINGDIR/latency_hist
++
++if test -d $HISTDIR
++then
++ cd $HISTDIR
++ for i in `find . | grep /reset$`
++ do
++ echo 1 >$i
++ done
++fi
++
++
++* Data format
++
++Latency data are stored with a resolution of one microsecond. The
++maximum latency is 10,240 microseconds. The data are only valid, if the
++overflow register is empty. Every output line contains the latency in
++microseconds in the first row and the number of samples in the second
++row. To display only lines with a positive latency count, use, for
++example,
++
++grep -v " 0$" /sys/kernel/debug/tracing/latency_hist/preemptoff/CPU0
++
++#Minimum latency: 0 microseconds.
++#Average latency: 0 microseconds.
++#Maximum latency: 25 microseconds.
++#Total samples: 3104770694
++#There are 0 samples greater or equal than 10240 microseconds
++#usecs samples
++ 0 2984486876
++ 1 49843506
++ 2 58219047
++ 3 5348126
++ 4 2187960
++ 5 3388262
++ 6 959289
++ 7 208294
++ 8 40420
++ 9 4485
++ 10 14918
++ 11 18340
++ 12 25052
++ 13 19455
++ 14 5602
++ 15 969
++ 16 47
++ 17 18
++ 18 14
++ 19 1
++ 20 3
++ 21 2
++ 22 5
++ 23 2
++ 25 1
++
++
++* Wakeup latency of a selected process
++
++To only collect wakeup latency data of a particular process, write the
++PID of the requested process to
++
++/sys/kernel/debug/tracing/latency_hist/wakeup/pid
++
++PIDs are not considered, if this variable is set to 0.
++
++
++* Details of the process with the highest wakeup latency so far
++
++Selected data of the process that suffered from the highest wakeup
++latency that occurred in a particular CPU are available in the file
++
++/sys/kernel/debug/tracing/latency_hist/wakeup/max_latency-CPUx.
++
++In addition, other relevant system data at the time when the
++latency occurred are given.
++
++The format of the data is (all in one line):
++<PID> <Priority> <Latency> (<Timeroffset>) <Command> \
++<- <PID> <Priority> <Command> <Timestamp>
++
++The value of <Timeroffset> is only relevant in the combined timer
++and wakeup latency recording. In the wakeup recording, it is
++always 0, in the missed_timer_offsets recording, it is the same
++as <Latency>.
++
++When retrospectively searching for the origin of a latency and
++tracing was not enabled, it may be helpful to know the name and
++some basic data of the task that (finally) was switching to the
++late real-tlme task. In addition to the victim's data, also the
++data of the possible culprit are therefore displayed after the
++"<-" symbol.
++
++Finally, the timestamp of the time when the latency occurred
++in <seconds>.<microseconds> after the most recent system boot
++is provided.
++
++These data are also reset when the wakeup histogram is reset.
+diff -Nur linux-4.8.15.orig/drivers/acpi/acpica/acglobal.h linux-4.8.15/drivers/acpi/acpica/acglobal.h
+--- linux-4.8.15.orig/drivers/acpi/acpica/acglobal.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/acpi/acpica/acglobal.h 2017-01-01 17:07:13.707277269 +0100
+@@ -116,7 +116,7 @@
+ * interrupt level
+ */
+ ACPI_GLOBAL(acpi_spinlock, acpi_gbl_gpe_lock); /* For GPE data structs and registers */
+-ACPI_GLOBAL(acpi_spinlock, acpi_gbl_hardware_lock); /* For ACPI H/W except GPE registers */
++ACPI_GLOBAL(acpi_raw_spinlock, acpi_gbl_hardware_lock); /* For ACPI H/W except GPE registers */
+ ACPI_GLOBAL(acpi_spinlock, acpi_gbl_reference_count_lock);
+
+ /* Mutex for _OSI support */
+diff -Nur linux-4.8.15.orig/drivers/acpi/acpica/hwregs.c linux-4.8.15/drivers/acpi/acpica/hwregs.c
+--- linux-4.8.15.orig/drivers/acpi/acpica/hwregs.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/acpi/acpica/hwregs.c 2017-01-01 17:07:13.719278046 +0100
+@@ -363,14 +363,14 @@
+ ACPI_BITMASK_ALL_FIXED_STATUS,
+ ACPI_FORMAT_UINT64(acpi_gbl_xpm1a_status.address)));
+
+- lock_flags = acpi_os_acquire_lock(acpi_gbl_hardware_lock);
++ raw_spin_lock_irqsave(acpi_gbl_hardware_lock, lock_flags);
+
+ /* Clear the fixed events in PM1 A/B */
+
+ status = acpi_hw_register_write(ACPI_REGISTER_PM1_STATUS,
+ ACPI_BITMASK_ALL_FIXED_STATUS);
+
+- acpi_os_release_lock(acpi_gbl_hardware_lock, lock_flags);
++ raw_spin_unlock_irqrestore(acpi_gbl_hardware_lock, lock_flags);
+
+ if (ACPI_FAILURE(status)) {
+ goto exit;
+diff -Nur linux-4.8.15.orig/drivers/acpi/acpica/hwxface.c linux-4.8.15/drivers/acpi/acpica/hwxface.c
+--- linux-4.8.15.orig/drivers/acpi/acpica/hwxface.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/acpi/acpica/hwxface.c 2017-01-01 17:07:13.719278046 +0100
+@@ -373,7 +373,7 @@
+ return_ACPI_STATUS(AE_BAD_PARAMETER);
+ }
+
+- lock_flags = acpi_os_acquire_lock(acpi_gbl_hardware_lock);
++ raw_spin_lock_irqsave(acpi_gbl_hardware_lock, lock_flags);
+
+ /*
+ * At this point, we know that the parent register is one of the
+@@ -434,7 +434,7 @@
+
+ unlock_and_exit:
+
+- acpi_os_release_lock(acpi_gbl_hardware_lock, lock_flags);
++ raw_spin_unlock_irqrestore(acpi_gbl_hardware_lock, lock_flags);
+ return_ACPI_STATUS(status);
+ }
+
+diff -Nur linux-4.8.15.orig/drivers/acpi/acpica/utmutex.c linux-4.8.15/drivers/acpi/acpica/utmutex.c
+--- linux-4.8.15.orig/drivers/acpi/acpica/utmutex.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/acpi/acpica/utmutex.c 2017-01-01 17:07:13.727278551 +0100
+@@ -88,7 +88,7 @@
+ return_ACPI_STATUS (status);
+ }
+
+- status = acpi_os_create_lock (&acpi_gbl_hardware_lock);
++ status = acpi_os_create_raw_lock (&acpi_gbl_hardware_lock);
+ if (ACPI_FAILURE (status)) {
+ return_ACPI_STATUS (status);
+ }
+@@ -145,7 +145,7 @@
+ /* Delete the spinlocks */
+
+ acpi_os_delete_lock(acpi_gbl_gpe_lock);
+- acpi_os_delete_lock(acpi_gbl_hardware_lock);
++ acpi_os_delete_raw_lock(acpi_gbl_hardware_lock);
+ acpi_os_delete_lock(acpi_gbl_reference_count_lock);
+
+ /* Delete the reader/writer lock */
+diff -Nur linux-4.8.15.orig/drivers/ata/libata-sff.c linux-4.8.15/drivers/ata/libata-sff.c
+--- linux-4.8.15.orig/drivers/ata/libata-sff.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/ata/libata-sff.c 2017-01-01 17:07:13.759280614 +0100
+@@ -678,9 +678,9 @@
+ unsigned long flags;
+ unsigned int consumed;
+
+- local_irq_save(flags);
++ local_irq_save_nort(flags);
+ consumed = ata_sff_data_xfer32(dev, buf, buflen, rw);
+- local_irq_restore(flags);
++ local_irq_restore_nort(flags);
+
+ return consumed;
+ }
+@@ -719,7 +719,7 @@
+ unsigned long flags;
+
+ /* FIXME: use a bounce buffer */
+- local_irq_save(flags);
++ local_irq_save_nort(flags);
+ buf = kmap_atomic(page);
+
+ /* do the actual data transfer */
+@@ -727,7 +727,7 @@
+ do_write);
+
+ kunmap_atomic(buf);
+- local_irq_restore(flags);
++ local_irq_restore_nort(flags);
+ } else {
+ buf = page_address(page);
+ ap->ops->sff_data_xfer(qc->dev, buf + offset, qc->sect_size,
+@@ -864,7 +864,7 @@
+ unsigned long flags;
+
+ /* FIXME: use bounce buffer */
+- local_irq_save(flags);
++ local_irq_save_nort(flags);
+ buf = kmap_atomic(page);
+
+ /* do the actual data transfer */
+@@ -872,7 +872,7 @@
+ count, rw);
+
+ kunmap_atomic(buf);
+- local_irq_restore(flags);
++ local_irq_restore_nort(flags);
+ } else {
+ buf = page_address(page);
+ consumed = ap->ops->sff_data_xfer(dev, buf + offset,
+diff -Nur linux-4.8.15.orig/drivers/block/zram/zcomp.c linux-4.8.15/drivers/block/zram/zcomp.c
+--- linux-4.8.15.orig/drivers/block/zram/zcomp.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/block/zram/zcomp.c 2017-01-01 17:07:13.815284222 +0100
+@@ -118,12 +118,19 @@
+
+ struct zcomp_strm *zcomp_stream_get(struct zcomp *comp)
+ {
+- return *get_cpu_ptr(comp->stream);
++ struct zcomp_strm *zstrm;
++
++ zstrm = *this_cpu_ptr(comp->stream);
++ spin_lock(&zstrm->zcomp_lock);
++ return zstrm;
+ }
+
+ void zcomp_stream_put(struct zcomp *comp)
+ {
+- put_cpu_ptr(comp->stream);
++ struct zcomp_strm *zstrm;
++
++ zstrm = *this_cpu_ptr(comp->stream);
++ spin_unlock(&zstrm->zcomp_lock);
+ }
+
+ int zcomp_compress(struct zcomp_strm *zstrm,
+@@ -174,6 +181,7 @@
+ pr_err("Can't allocate a compression stream\n");
+ return NOTIFY_BAD;
+ }
++ spin_lock_init(&zstrm->zcomp_lock);
+ *per_cpu_ptr(comp->stream, cpu) = zstrm;
+ break;
+ case CPU_DEAD:
+diff -Nur linux-4.8.15.orig/drivers/block/zram/zcomp.h linux-4.8.15/drivers/block/zram/zcomp.h
+--- linux-4.8.15.orig/drivers/block/zram/zcomp.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/block/zram/zcomp.h 2017-01-01 17:07:13.823284735 +0100
+@@ -14,6 +14,7 @@
+ /* compression/decompression buffer */
+ void *buffer;
+ struct crypto_comp *tfm;
++ spinlock_t zcomp_lock;
+ };
+
+ /* dynamic per-device compression frontend */
+diff -Nur linux-4.8.15.orig/drivers/block/zram/zram_drv.c linux-4.8.15/drivers/block/zram/zram_drv.c
+--- linux-4.8.15.orig/drivers/block/zram/zram_drv.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/block/zram/zram_drv.c 2017-01-01 17:07:13.831285255 +0100
+@@ -519,6 +519,8 @@
+ goto out_error;
+ }
+
++ zram_meta_init_table_locks(meta, disksize);
++
+ return meta;
+
+ out_error:
+@@ -566,28 +568,28 @@
+ struct zram_meta *meta = zram->meta;
+ unsigned long handle;
+ unsigned int size;
++ struct zcomp_strm *zstrm;
+
+- bit_spin_lock(ZRAM_ACCESS, &meta->table[index].value);
++ zram_lock_table(&meta->table[index]);
+ handle = meta->table[index].handle;
+ size = zram_get_obj_size(meta, index);
+
+ if (!handle || zram_test_flag(meta, index, ZRAM_ZERO)) {
+- bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value);
++ zram_unlock_table(&meta->table[index]);
+ clear_page(mem);
+ return 0;
+ }
+
++ zstrm = zcomp_stream_get(zram->comp);
+ cmem = zs_map_object(meta->mem_pool, handle, ZS_MM_RO);
+ if (size == PAGE_SIZE) {
+ copy_page(mem, cmem);
+ } else {
+- struct zcomp_strm *zstrm = zcomp_stream_get(zram->comp);
+-
+ ret = zcomp_decompress(zstrm, cmem, size, mem);
+- zcomp_stream_put(zram->comp);
+ }
+ zs_unmap_object(meta->mem_pool, handle);
+- bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value);
++ zcomp_stream_put(zram->comp);
++ zram_unlock_table(&meta->table[index]);
+
+ /* Should NEVER happen. Return bio error if it does. */
+ if (unlikely(ret)) {
+@@ -607,14 +609,14 @@
+ struct zram_meta *meta = zram->meta;
+ page = bvec->bv_page;
+
+- bit_spin_lock(ZRAM_ACCESS, &meta->table[index].value);
++ zram_lock_table(&meta->table[index]);
+ if (unlikely(!meta->table[index].handle) ||
+ zram_test_flag(meta, index, ZRAM_ZERO)) {
+- bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value);
++ zram_unlock_table(&meta->table[index]);
+ handle_zero_page(bvec);
+ return 0;
+ }
+- bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value);
++ zram_unlock_table(&meta->table[index]);
+
+ if (is_partial_io(bvec))
+ /* Use a temporary buffer to decompress the page */
+@@ -691,10 +693,10 @@
+ if (user_mem)
+ kunmap_atomic(user_mem);
+ /* Free memory associated with this sector now. */
+- bit_spin_lock(ZRAM_ACCESS, &meta->table[index].value);
++ zram_lock_table(&meta->table[index]);
+ zram_free_page(zram, index);
+ zram_set_flag(meta, index, ZRAM_ZERO);
+- bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value);
++ zram_unlock_table(&meta->table[index]);
+
+ atomic64_inc(&zram->stats.zero_pages);
+ ret = 0;
+@@ -785,12 +787,12 @@
+ * Free memory associated with this sector
+ * before overwriting unused sectors.
+ */
+- bit_spin_lock(ZRAM_ACCESS, &meta->table[index].value);
++ zram_lock_table(&meta->table[index]);
+ zram_free_page(zram, index);
+
+ meta->table[index].handle = handle;
+ zram_set_obj_size(meta, index, clen);
+- bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value);
++ zram_unlock_table(&meta->table[index]);
+
+ /* Update stats */
+ atomic64_add(clen, &zram->stats.compr_data_size);
+@@ -833,9 +835,9 @@
+ }
+
+ while (n >= PAGE_SIZE) {
+- bit_spin_lock(ZRAM_ACCESS, &meta->table[index].value);
++ zram_lock_table(&meta->table[index]);
+ zram_free_page(zram, index);
+- bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value);
++ zram_unlock_table(&meta->table[index]);
+ atomic64_inc(&zram->stats.notify_free);
+ index++;
+ n -= PAGE_SIZE;
+@@ -964,9 +966,9 @@
+ zram = bdev->bd_disk->private_data;
+ meta = zram->meta;
+
+- bit_spin_lock(ZRAM_ACCESS, &meta->table[index].value);
++ zram_lock_table(&meta->table[index]);
+ zram_free_page(zram, index);
+- bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value);
++ zram_unlock_table(&meta->table[index]);
+ atomic64_inc(&zram->stats.notify_free);
+ }
+
+diff -Nur linux-4.8.15.orig/drivers/block/zram/zram_drv.h linux-4.8.15/drivers/block/zram/zram_drv.h
+--- linux-4.8.15.orig/drivers/block/zram/zram_drv.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/block/zram/zram_drv.h 2017-01-01 17:07:13.831285255 +0100
+@@ -73,6 +73,9 @@
+ struct zram_table_entry {
+ unsigned long handle;
+ unsigned long value;
++#ifdef CONFIG_PREEMPT_RT_BASE
++ spinlock_t lock;
++#endif
+ };
+
+ struct zram_stats {
+@@ -120,4 +123,42 @@
+ */
+ bool claim; /* Protected by bdev->bd_mutex */
+ };
++
++#ifndef CONFIG_PREEMPT_RT_BASE
++static inline void zram_lock_table(struct zram_table_entry *table)
++{
++ bit_spin_lock(ZRAM_ACCESS, &table->value);
++}
++
++static inline void zram_unlock_table(struct zram_table_entry *table)
++{
++ bit_spin_unlock(ZRAM_ACCESS, &table->value);
++}
++
++static inline void zram_meta_init_table_locks(struct zram_meta *meta, u64 disksize) { }
++#else /* CONFIG_PREEMPT_RT_BASE */
++static inline void zram_lock_table(struct zram_table_entry *table)
++{
++ spin_lock(&table->lock);
++ __set_bit(ZRAM_ACCESS, &table->value);
++}
++
++static inline void zram_unlock_table(struct zram_table_entry *table)
++{
++ __clear_bit(ZRAM_ACCESS, &table->value);
++ spin_unlock(&table->lock);
++}
++
++static inline void zram_meta_init_table_locks(struct zram_meta *meta, u64 disksize)
++{
++ size_t num_pages = disksize >> PAGE_SHIFT;
++ size_t index;
++
++ for (index = 0; index < num_pages; index++) {
++ spinlock_t *lock = &meta->table[index].lock;
++ spin_lock_init(lock);
++ }
++}
++#endif /* CONFIG_PREEMPT_RT_BASE */
++
+ #endif
+diff -Nur linux-4.8.15.orig/drivers/char/random.c linux-4.8.15/drivers/char/random.c
+--- linux-4.8.15.orig/drivers/char/random.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/char/random.c 2017-01-01 17:07:13.863287315 +0100
+@@ -1028,8 +1028,6 @@
+ } sample;
+ long delta, delta2, delta3;
+
+- preempt_disable();
+-
+ sample.jiffies = jiffies;
+ sample.cycles = random_get_entropy();
+ sample.num = num;
+@@ -1070,7 +1068,6 @@
+ */
+ credit_entropy_bits(r, min_t(int, fls(delta>>1), 11));
+ }
+- preempt_enable();
+ }
+
+ void add_input_randomness(unsigned int type, unsigned int code,
+@@ -1123,28 +1120,27 @@
+ return *(ptr + f->reg_idx++);
+ }
+
+-void add_interrupt_randomness(int irq, int irq_flags)
++void add_interrupt_randomness(int irq, int irq_flags, __u64 ip)
+ {
+ struct entropy_store *r;
+ struct fast_pool *fast_pool = this_cpu_ptr(&irq_randomness);
+- struct pt_regs *regs = get_irq_regs();
+ unsigned long now = jiffies;
+ cycles_t cycles = random_get_entropy();
+ __u32 c_high, j_high;
+- __u64 ip;
+ unsigned long seed;
+ int credit = 0;
+
+ if (cycles == 0)
+- cycles = get_reg(fast_pool, regs);
++ cycles = get_reg(fast_pool, NULL);
+ c_high = (sizeof(cycles) > 4) ? cycles >> 32 : 0;
+ j_high = (sizeof(now) > 4) ? now >> 32 : 0;
+ fast_pool->pool[0] ^= cycles ^ j_high ^ irq;
+ fast_pool->pool[1] ^= now ^ c_high;
+- ip = regs ? instruction_pointer(regs) : _RET_IP_;
++ if (!ip)
++ ip = _RET_IP_;
+ fast_pool->pool[2] ^= ip;
+ fast_pool->pool[3] ^= (sizeof(ip) > 4) ? ip >> 32 :
+- get_reg(fast_pool, regs);
++ get_reg(fast_pool, NULL);
+
+ fast_mix(fast_pool);
+ add_interrupt_bench(cycles);
+diff -Nur linux-4.8.15.orig/drivers/clocksource/tcb_clksrc.c linux-4.8.15/drivers/clocksource/tcb_clksrc.c
+--- linux-4.8.15.orig/drivers/clocksource/tcb_clksrc.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/clocksource/tcb_clksrc.c 2017-01-01 17:07:13.903289890 +0100
+@@ -23,8 +23,7 @@
+ * this 32 bit free-running counter. the second channel is not used.
+ *
+ * - The third channel may be used to provide a 16-bit clockevent
+- * source, used in either periodic or oneshot mode. This runs
+- * at 32 KiHZ, and can handle delays of up to two seconds.
++ * source, used in either periodic or oneshot mode.
+ *
+ * A boot clocksource and clockevent source are also currently needed,
+ * unless the relevant platforms (ARM/AT91, AVR32/AT32) are changed so
+@@ -74,6 +73,8 @@
+ struct tc_clkevt_device {
+ struct clock_event_device clkevt;
+ struct clk *clk;
++ bool clk_enabled;
++ u32 freq;
+ void __iomem *regs;
+ };
+
+@@ -82,15 +83,26 @@
+ return container_of(clkevt, struct tc_clkevt_device, clkevt);
+ }
+
+-/* For now, we always use the 32K clock ... this optimizes for NO_HZ,
+- * because using one of the divided clocks would usually mean the
+- * tick rate can never be less than several dozen Hz (vs 0.5 Hz).
+- *
+- * A divided clock could be good for high resolution timers, since
+- * 30.5 usec resolution can seem "low".
+- */
+ static u32 timer_clock;
+
++static void tc_clk_disable(struct clock_event_device *d)
++{
++ struct tc_clkevt_device *tcd = to_tc_clkevt(d);
++
++ clk_disable(tcd->clk);
++ tcd->clk_enabled = false;
++}
++
++static void tc_clk_enable(struct clock_event_device *d)
++{
++ struct tc_clkevt_device *tcd = to_tc_clkevt(d);
++
++ if (tcd->clk_enabled)
++ return;
++ clk_enable(tcd->clk);
++ tcd->clk_enabled = true;
++}
++
+ static int tc_shutdown(struct clock_event_device *d)
+ {
+ struct tc_clkevt_device *tcd = to_tc_clkevt(d);
+@@ -98,8 +110,14 @@
+
+ __raw_writel(0xff, regs + ATMEL_TC_REG(2, IDR));
+ __raw_writel(ATMEL_TC_CLKDIS, regs + ATMEL_TC_REG(2, CCR));
++ return 0;
++}
++
++static int tc_shutdown_clk_off(struct clock_event_device *d)
++{
++ tc_shutdown(d);
+ if (!clockevent_state_detached(d))
+- clk_disable(tcd->clk);
++ tc_clk_disable(d);
+
+ return 0;
+ }
+@@ -112,9 +130,9 @@
+ if (clockevent_state_oneshot(d) || clockevent_state_periodic(d))
+ tc_shutdown(d);
+
+- clk_enable(tcd->clk);
++ tc_clk_enable(d);
+
+- /* slow clock, count up to RC, then irq and stop */
++ /* count up to RC, then irq and stop */
+ __raw_writel(timer_clock | ATMEL_TC_CPCSTOP | ATMEL_TC_WAVE |
+ ATMEL_TC_WAVESEL_UP_AUTO, regs + ATMEL_TC_REG(2, CMR));
+ __raw_writel(ATMEL_TC_CPCS, regs + ATMEL_TC_REG(2, IER));
+@@ -134,12 +152,12 @@
+ /* By not making the gentime core emulate periodic mode on top
+ * of oneshot, we get lower overhead and improved accuracy.
+ */
+- clk_enable(tcd->clk);
++ tc_clk_enable(d);
+
+- /* slow clock, count up to RC, then irq and restart */
++ /* count up to RC, then irq and restart */
+ __raw_writel(timer_clock | ATMEL_TC_WAVE | ATMEL_TC_WAVESEL_UP_AUTO,
+ regs + ATMEL_TC_REG(2, CMR));
+- __raw_writel((32768 + HZ / 2) / HZ, tcaddr + ATMEL_TC_REG(2, RC));
++ __raw_writel((tcd->freq + HZ / 2) / HZ, tcaddr + ATMEL_TC_REG(2, RC));
+
+ /* Enable clock and interrupts on RC compare */
+ __raw_writel(ATMEL_TC_CPCS, regs + ATMEL_TC_REG(2, IER));
+@@ -166,9 +184,13 @@
+ .features = CLOCK_EVT_FEAT_PERIODIC |
+ CLOCK_EVT_FEAT_ONESHOT,
+ /* Should be lower than at91rm9200's system timer */
++#ifdef CONFIG_ATMEL_TCB_CLKSRC_USE_SLOW_CLOCK
+ .rating = 125,
++#else
++ .rating = 200,
++#endif
+ .set_next_event = tc_next_event,
+- .set_state_shutdown = tc_shutdown,
++ .set_state_shutdown = tc_shutdown_clk_off,
+ .set_state_periodic = tc_set_periodic,
+ .set_state_oneshot = tc_set_oneshot,
+ },
+@@ -188,8 +210,9 @@
+ return IRQ_NONE;
+ }
+
+-static int __init setup_clkevents(struct atmel_tc *tc, int clk32k_divisor_idx)
++static int __init setup_clkevents(struct atmel_tc *tc, int divisor_idx)
+ {
++ unsigned divisor = atmel_tc_divisors[divisor_idx];
+ int ret;
+ struct clk *t2_clk = tc->clk[2];
+ int irq = tc->irq[2];
+@@ -210,7 +233,11 @@
+ clkevt.regs = tc->regs;
+ clkevt.clk = t2_clk;
+
+- timer_clock = clk32k_divisor_idx;
++ timer_clock = divisor_idx;
++ if (!divisor)
++ clkevt.freq = 32768;
++ else
++ clkevt.freq = clk_get_rate(t2_clk) / divisor;
+
+ clkevt.clkevt.cpumask = cpumask_of(0);
+
+@@ -221,7 +248,7 @@
+ return ret;
+ }
+
+- clockevents_config_and_register(&clkevt.clkevt, 32768, 1, 0xffff);
++ clockevents_config_and_register(&clkevt.clkevt, clkevt.freq, 1, 0xffff);
+
+ return ret;
+ }
+@@ -358,7 +385,11 @@
+ goto err_disable_t1;
+
+ /* channel 2: periodic and oneshot timer support */
++#ifdef CONFIG_ATMEL_TCB_CLKSRC_USE_SLOW_CLOCK
+ ret = setup_clkevents(tc, clk32k_divisor_idx);
++#else
++ ret = setup_clkevents(tc, best_divisor_idx);
++#endif
+ if (ret)
+ goto err_unregister_clksrc;
+
+diff -Nur linux-4.8.15.orig/drivers/clocksource/timer-atmel-pit.c linux-4.8.15/drivers/clocksource/timer-atmel-pit.c
+--- linux-4.8.15.orig/drivers/clocksource/timer-atmel-pit.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/clocksource/timer-atmel-pit.c 2017-01-01 17:07:13.911290405 +0100
+@@ -46,6 +46,7 @@
+ u32 cycle;
+ u32 cnt;
+ unsigned int irq;
++ bool irq_requested;
+ struct clk *mck;
+ };
+
+@@ -96,15 +97,29 @@
+
+ /* disable irq, leaving the clocksource active */
+ pit_write(data->base, AT91_PIT_MR, (data->cycle - 1) | AT91_PIT_PITEN);
++ if (data->irq_requested) {
++ free_irq(data->irq, data);
++ data->irq_requested = false;
++ }
+ return 0;
+ }
+
++static irqreturn_t at91sam926x_pit_interrupt(int irq, void *dev_id);
+ /*
+ * Clockevent device: interrupts every 1/HZ (== pit_cycles * MCK/16)
+ */
+ static int pit_clkevt_set_periodic(struct clock_event_device *dev)
+ {
+ struct pit_data *data = clkevt_to_pit_data(dev);
++ int ret;
++
++ ret = request_irq(data->irq, at91sam926x_pit_interrupt,
++ IRQF_SHARED | IRQF_TIMER | IRQF_IRQPOLL,
++ "at91_tick", data);
++ if (ret)
++ panic(pr_fmt("Unable to setup IRQ\n"));
++
++ data->irq_requested = true;
+
+ /* update clocksource counter */
+ data->cnt += data->cycle * PIT_PICNT(pit_read(data->base, AT91_PIT_PIVR));
+@@ -211,15 +226,6 @@
+ return ret;
+ }
+
+- /* Set up irq handler */
+- ret = request_irq(data->irq, at91sam926x_pit_interrupt,
+- IRQF_SHARED | IRQF_TIMER | IRQF_IRQPOLL,
+- "at91_tick", data);
+- if (ret) {
+- pr_err("Unable to setup IRQ\n");
+- return ret;
+- }
+-
+ /* Set up and register clockevents */
+ data->clkevt.name = "pit";
+ data->clkevt.features = CLOCK_EVT_FEAT_PERIODIC;
+diff -Nur linux-4.8.15.orig/drivers/clocksource/timer-atmel-st.c linux-4.8.15/drivers/clocksource/timer-atmel-st.c
+--- linux-4.8.15.orig/drivers/clocksource/timer-atmel-st.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/clocksource/timer-atmel-st.c 2017-01-01 17:07:13.911290405 +0100
+@@ -115,18 +115,29 @@
+ last_crtr = read_CRTR();
+ }
+
++static int atmel_st_irq;
++
+ static int clkevt32k_shutdown(struct clock_event_device *evt)
+ {
+ clkdev32k_disable_and_flush_irq();
+ irqmask = 0;
+ regmap_write(regmap_st, AT91_ST_IER, irqmask);
++ free_irq(atmel_st_irq, regmap_st);
+ return 0;
+ }
+
+ static int clkevt32k_set_oneshot(struct clock_event_device *dev)
+ {
++ int ret;
++
+ clkdev32k_disable_and_flush_irq();
+
++ ret = request_irq(atmel_st_irq, at91rm9200_timer_interrupt,
++ IRQF_SHARED | IRQF_TIMER | IRQF_IRQPOLL,
++ "at91_tick", regmap_st);
++ if (ret)
++ panic(pr_fmt("Unable to setup IRQ\n"));
++
+ /*
+ * ALM for oneshot irqs, set by next_event()
+ * before 32 seconds have passed.
+@@ -139,8 +150,16 @@
+
+ static int clkevt32k_set_periodic(struct clock_event_device *dev)
+ {
++ int ret;
++
+ clkdev32k_disable_and_flush_irq();
+
++ ret = request_irq(atmel_st_irq, at91rm9200_timer_interrupt,
++ IRQF_SHARED | IRQF_TIMER | IRQF_IRQPOLL,
++ "at91_tick", regmap_st);
++ if (ret)
++ panic(pr_fmt("Unable to setup IRQ\n"));
++
+ /* PIT for periodic irqs; fixed rate of 1/HZ */
+ irqmask = AT91_ST_PITS;
+ regmap_write(regmap_st, AT91_ST_PIMR, timer_latch);
+@@ -198,7 +217,7 @@
+ {
+ struct clk *sclk;
+ unsigned int sclk_rate, val;
+- int irq, ret;
++ int ret;
+
+ regmap_st = syscon_node_to_regmap(node);
+ if (IS_ERR(regmap_st)) {
+@@ -212,21 +231,12 @@
+ regmap_read(regmap_st, AT91_ST_SR, &val);
+
+ /* Get the interrupts property */
+- irq = irq_of_parse_and_map(node, 0);
+- if (!irq) {
++ atmel_st_irq = irq_of_parse_and_map(node, 0);
++ if (!atmel_st_irq) {
+ pr_err("Unable to get IRQ from DT\n");
+ return -EINVAL;
+ }
+
+- /* Make IRQs happen for the system timer */
+- ret = request_irq(irq, at91rm9200_timer_interrupt,
+- IRQF_SHARED | IRQF_TIMER | IRQF_IRQPOLL,
+- "at91_tick", regmap_st);
+- if (ret) {
+- pr_err("Unable to setup IRQ\n");
+- return ret;
+- }
+-
+ sclk = of_clk_get(node, 0);
+ if (IS_ERR(sclk)) {
+ pr_err("Unable to get slow clock\n");
+diff -Nur linux-4.8.15.orig/drivers/connector/cn_proc.c linux-4.8.15/drivers/connector/cn_proc.c
+--- linux-4.8.15.orig/drivers/connector/cn_proc.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/connector/cn_proc.c 2017-01-01 17:07:13.951292981 +0100
+@@ -32,6 +32,7 @@
+ #include <linux/pid_namespace.h>
+
+ #include <linux/cn_proc.h>
++#include <linux/locallock.h>
+
+ /*
+ * Size of a cn_msg followed by a proc_event structure. Since the
+@@ -54,10 +55,11 @@
+
+ /* proc_event_counts is used as the sequence number of the netlink message */
+ static DEFINE_PER_CPU(__u32, proc_event_counts) = { 0 };
++static DEFINE_LOCAL_IRQ_LOCK(send_msg_lock);
+
+ static inline void send_msg(struct cn_msg *msg)
+ {
+- preempt_disable();
++ local_lock(send_msg_lock);
+
+ msg->seq = __this_cpu_inc_return(proc_event_counts) - 1;
+ ((struct proc_event *)msg->data)->cpu = smp_processor_id();
+@@ -70,7 +72,7 @@
+ */
+ cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_NOWAIT);
+
+- preempt_enable();
++ local_unlock(send_msg_lock);
+ }
+
+ void proc_fork_connector(struct task_struct *task)
+diff -Nur linux-4.8.15.orig/drivers/cpufreq/Kconfig.x86 linux-4.8.15/drivers/cpufreq/Kconfig.x86
+--- linux-4.8.15.orig/drivers/cpufreq/Kconfig.x86 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/cpufreq/Kconfig.x86 2017-01-01 17:07:13.951292981 +0100
+@@ -124,7 +124,7 @@
+
+ config X86_POWERNOW_K8
+ tristate "AMD Opteron/Athlon64 PowerNow!"
+- depends on ACPI && ACPI_PROCESSOR && X86_ACPI_CPUFREQ
++ depends on ACPI && ACPI_PROCESSOR && X86_ACPI_CPUFREQ && !PREEMPT_RT_BASE
+ help
+ This adds the CPUFreq driver for K8/early Opteron/Athlon64 processors.
+ Support for K10 and newer processors is now in acpi-cpufreq.
+diff -Nur linux-4.8.15.orig/drivers/gpu/drm/i915/i915_gem_execbuffer.c linux-4.8.15/drivers/gpu/drm/i915/i915_gem_execbuffer.c
+--- linux-4.8.15.orig/drivers/gpu/drm/i915/i915_gem_execbuffer.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/gpu/drm/i915/i915_gem_execbuffer.c 2017-01-01 17:07:13.983295041 +0100
+@@ -1302,7 +1302,9 @@
+ if (ret)
+ return ret;
+
++#ifndef CONFIG_PREEMPT_RT_BASE
+ trace_i915_gem_ring_dispatch(params->request, params->dispatch_flags);
++#endif
+
+ i915_gem_execbuffer_move_to_active(vmas, params->request);
+
+diff -Nur linux-4.8.15.orig/drivers/gpu/drm/i915/i915_gem_shrinker.c linux-4.8.15/drivers/gpu/drm/i915/i915_gem_shrinker.c
+--- linux-4.8.15.orig/drivers/gpu/drm/i915/i915_gem_shrinker.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/gpu/drm/i915/i915_gem_shrinker.c 2017-01-01 17:07:13.987295307 +0100
+@@ -40,7 +40,7 @@
+ if (!mutex_is_locked(mutex))
+ return false;
+
+-#if defined(CONFIG_DEBUG_MUTEXES) || defined(CONFIG_MUTEX_SPIN_ON_OWNER)
++#if (defined(CONFIG_DEBUG_MUTEXES) || defined(CONFIG_MUTEX_SPIN_ON_OWNER)) && !defined(CONFIG_PREEMPT_RT_BASE)
+ return mutex->owner == task;
+ #else
+ /* Since UP may be pre-empted, we cannot assume that we own the lock */
+diff -Nur linux-4.8.15.orig/drivers/gpu/drm/i915/i915_irq.c linux-4.8.15/drivers/gpu/drm/i915/i915_irq.c
+--- linux-4.8.15.orig/drivers/gpu/drm/i915/i915_irq.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/gpu/drm/i915/i915_irq.c 2017-01-01 17:07:14.007296588 +0100
+@@ -812,6 +812,7 @@
+ spin_lock_irqsave(&dev_priv->uncore.lock, irqflags);
+
+ /* preempt_disable_rt() should go right here in PREEMPT_RT patchset. */
++ preempt_disable_rt();
+
+ /* Get optional system timestamp before query. */
+ if (stime)
+@@ -863,6 +864,7 @@
+ *etime = ktime_get();
+
+ /* preempt_enable_rt() should go right here in PREEMPT_RT patchset. */
++ preempt_enable_rt();
+
+ spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags);
+
+diff -Nur linux-4.8.15.orig/drivers/gpu/drm/i915/intel_display.c linux-4.8.15/drivers/gpu/drm/i915/intel_display.c
+--- linux-4.8.15.orig/drivers/gpu/drm/i915/intel_display.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/gpu/drm/i915/intel_display.c 2017-01-01 17:07:14.079301234 +0100
+@@ -11670,7 +11670,7 @@
+ struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
+ struct intel_flip_work *work;
+
+- WARN_ON(!in_interrupt());
++ WARN_ON_NONRT(!in_interrupt());
+
+ if (crtc == NULL)
+ return;
+diff -Nur linux-4.8.15.orig/drivers/gpu/drm/i915/intel_sprite.c linux-4.8.15/drivers/gpu/drm/i915/intel_sprite.c
+--- linux-4.8.15.orig/drivers/gpu/drm/i915/intel_sprite.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/gpu/drm/i915/intel_sprite.c 2017-01-01 17:07:14.091301999 +0100
+@@ -38,6 +38,7 @@
+ #include "intel_drv.h"
+ #include <drm/i915_drm.h>
+ #include "i915_drv.h"
++#include <linux/locallock.h>
+
+ static bool
+ format_is_yuv(uint32_t format)
+@@ -64,6 +65,8 @@
+ 1000 * adjusted_mode->crtc_htotal);
+ }
+
++static DEFINE_LOCAL_IRQ_LOCK(pipe_update_lock);
++
+ /**
+ * intel_pipe_update_start() - start update of a set of display registers
+ * @crtc: the crtc of which the registers are going to be updated
+@@ -94,7 +97,7 @@
+ min = vblank_start - intel_usecs_to_scanlines(adjusted_mode, 100);
+ max = vblank_start - 1;
+
+- local_irq_disable();
++ local_lock_irq(pipe_update_lock);
+
+ if (min <= 0 || max <= 0)
+ return;
+@@ -124,11 +127,11 @@
+ break;
+ }
+
+- local_irq_enable();
++ local_unlock_irq(pipe_update_lock);
+
+ timeout = schedule_timeout(timeout);
+
+- local_irq_disable();
++ local_lock_irq(pipe_update_lock);
+ }
+
+ finish_wait(wq, &wait);
+@@ -180,7 +183,7 @@
+ crtc->base.state->event = NULL;
+ }
+
+- local_irq_enable();
++ local_unlock_irq(pipe_update_lock);
+
+ if (crtc->debug.start_vbl_count &&
+ crtc->debug.start_vbl_count != end_vbl_count) {
+diff -Nur linux-4.8.15.orig/drivers/gpu/drm/msm/msm_gem_shrinker.c linux-4.8.15/drivers/gpu/drm/msm/msm_gem_shrinker.c
+--- linux-4.8.15.orig/drivers/gpu/drm/msm/msm_gem_shrinker.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/gpu/drm/msm/msm_gem_shrinker.c 2017-01-01 17:07:14.095302264 +0100
+@@ -23,7 +23,7 @@
+ if (!mutex_is_locked(mutex))
+ return false;
+
+-#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_MUTEXES)
++#if (defined(CONFIG_SMP) || defined(CONFIG_DEBUG_MUTEXES)) && !defined(CONFIG_PREEMPT_RT_BASE)
+ return mutex->owner == task;
+ #else
+ /* Since UP may be pre-empted, we cannot assume that we own the lock */
+diff -Nur linux-4.8.15.orig/drivers/gpu/drm/radeon/radeon_display.c linux-4.8.15/drivers/gpu/drm/radeon/radeon_display.c
+--- linux-4.8.15.orig/drivers/gpu/drm/radeon/radeon_display.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/gpu/drm/radeon/radeon_display.c 2017-01-01 17:07:14.135304831 +0100
+@@ -1869,6 +1869,7 @@
+ struct radeon_device *rdev = dev->dev_private;
+
+ /* preempt_disable_rt() should go right here in PREEMPT_RT patchset. */
++ preempt_disable_rt();
+
+ /* Get optional system timestamp before query. */
+ if (stime)
+@@ -1961,6 +1962,7 @@
+ *etime = ktime_get();
+
+ /* preempt_enable_rt() should go right here in PREEMPT_RT patchset. */
++ preempt_enable_rt();
+
+ /* Decode into vertical and horizontal scanout position. */
+ *vpos = position & 0x1fff;
+diff -Nur linux-4.8.15.orig/drivers/hv/vmbus_drv.c linux-4.8.15/drivers/hv/vmbus_drv.c
+--- linux-4.8.15.orig/drivers/hv/vmbus_drv.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/hv/vmbus_drv.c 2017-01-01 17:07:14.187308183 +0100
+@@ -761,6 +761,8 @@
+ void *page_addr;
+ struct hv_message *msg;
+ union hv_synic_event_flags *event;
++ struct pt_regs *regs = get_irq_regs();
++ u64 ip = regs ? instruction_pointer(regs) : 0;
+ bool handled = false;
+
+ page_addr = hv_context.synic_event_page[cpu];
+@@ -808,7 +810,7 @@
+ tasklet_schedule(hv_context.msg_dpc[cpu]);
+ }
+
+- add_interrupt_randomness(HYPERVISOR_CALLBACK_VECTOR, 0);
++ add_interrupt_randomness(HYPERVISOR_CALLBACK_VECTOR, 0, ip);
+ }
+
+
+diff -Nur linux-4.8.15.orig/drivers/ide/alim15x3.c linux-4.8.15/drivers/ide/alim15x3.c
+--- linux-4.8.15.orig/drivers/ide/alim15x3.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/ide/alim15x3.c 2017-01-01 17:07:14.227310759 +0100
+@@ -234,7 +234,7 @@
+
+ isa_dev = pci_get_device(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M1533, NULL);
+
+- local_irq_save(flags);
++ local_irq_save_nort(flags);
+
+ if (m5229_revision < 0xC2) {
+ /*
+@@ -325,7 +325,7 @@
+ }
+ pci_dev_put(north);
+ pci_dev_put(isa_dev);
+- local_irq_restore(flags);
++ local_irq_restore_nort(flags);
+ return 0;
+ }
+
+diff -Nur linux-4.8.15.orig/drivers/ide/hpt366.c linux-4.8.15/drivers/ide/hpt366.c
+--- linux-4.8.15.orig/drivers/ide/hpt366.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/ide/hpt366.c 2017-01-01 17:07:14.243311792 +0100
+@@ -1236,7 +1236,7 @@
+
+ dma_old = inb(base + 2);
+
+- local_irq_save(flags);
++ local_irq_save_nort(flags);
+
+ dma_new = dma_old;
+ pci_read_config_byte(dev, hwif->channel ? 0x4b : 0x43, &masterdma);
+@@ -1247,7 +1247,7 @@
+ if (dma_new != dma_old)
+ outb(dma_new, base + 2);
+
+- local_irq_restore(flags);
++ local_irq_restore_nort(flags);
+
+ printk(KERN_INFO " %s: BM-DMA at 0x%04lx-0x%04lx\n",
+ hwif->name, base, base + 7);
+diff -Nur linux-4.8.15.orig/drivers/ide/ide-io.c linux-4.8.15/drivers/ide/ide-io.c
+--- linux-4.8.15.orig/drivers/ide/ide-io.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/ide/ide-io.c 2017-01-01 17:07:14.243311792 +0100
+@@ -659,7 +659,7 @@
+ /* disable_irq_nosync ?? */
+ disable_irq(hwif->irq);
+ /* local CPU only, as if we were handling an interrupt */
+- local_irq_disable();
++ local_irq_disable_nort();
+ if (hwif->polling) {
+ startstop = handler(drive);
+ } else if (drive_is_ready(drive)) {
+diff -Nur linux-4.8.15.orig/drivers/ide/ide-iops.c linux-4.8.15/drivers/ide/ide-iops.c
+--- linux-4.8.15.orig/drivers/ide/ide-iops.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/ide/ide-iops.c 2017-01-01 17:07:14.247312048 +0100
+@@ -129,12 +129,12 @@
+ if ((stat & ATA_BUSY) == 0)
+ break;
+
+- local_irq_restore(flags);
++ local_irq_restore_nort(flags);
+ *rstat = stat;
+ return -EBUSY;
+ }
+ }
+- local_irq_restore(flags);
++ local_irq_restore_nort(flags);
+ }
+ /*
+ * Allow status to settle, then read it again.
+diff -Nur linux-4.8.15.orig/drivers/ide/ide-io-std.c linux-4.8.15/drivers/ide/ide-io-std.c
+--- linux-4.8.15.orig/drivers/ide/ide-io-std.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/ide/ide-io-std.c 2017-01-01 17:07:14.243311792 +0100
+@@ -175,7 +175,7 @@
+ unsigned long uninitialized_var(flags);
+
+ if ((io_32bit & 2) && !mmio) {
+- local_irq_save(flags);
++ local_irq_save_nort(flags);
+ ata_vlb_sync(io_ports->nsect_addr);
+ }
+
+@@ -186,7 +186,7 @@
+ insl(data_addr, buf, words);
+
+ if ((io_32bit & 2) && !mmio)
+- local_irq_restore(flags);
++ local_irq_restore_nort(flags);
+
+ if (((len + 1) & 3) < 2)
+ return;
+@@ -219,7 +219,7 @@
+ unsigned long uninitialized_var(flags);
+
+ if ((io_32bit & 2) && !mmio) {
+- local_irq_save(flags);
++ local_irq_save_nort(flags);
+ ata_vlb_sync(io_ports->nsect_addr);
+ }
+
+@@ -230,7 +230,7 @@
+ outsl(data_addr, buf, words);
+
+ if ((io_32bit & 2) && !mmio)
+- local_irq_restore(flags);
++ local_irq_restore_nort(flags);
+
+ if (((len + 1) & 3) < 2)
+ return;
+diff -Nur linux-4.8.15.orig/drivers/ide/ide-probe.c linux-4.8.15/drivers/ide/ide-probe.c
+--- linux-4.8.15.orig/drivers/ide/ide-probe.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/ide/ide-probe.c 2017-01-01 17:07:14.247312048 +0100
+@@ -196,10 +196,10 @@
+ int bswap = 1;
+
+ /* local CPU only; some systems need this */
+- local_irq_save(flags);
++ local_irq_save_nort(flags);
+ /* read 512 bytes of id info */
+ hwif->tp_ops->input_data(drive, NULL, id, SECTOR_SIZE);
+- local_irq_restore(flags);
++ local_irq_restore_nort(flags);
+
+ drive->dev_flags |= IDE_DFLAG_ID_READ;
+ #ifdef DEBUG
+diff -Nur linux-4.8.15.orig/drivers/ide/ide-taskfile.c linux-4.8.15/drivers/ide/ide-taskfile.c
+--- linux-4.8.15.orig/drivers/ide/ide-taskfile.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/ide/ide-taskfile.c 2017-01-01 17:07:14.255312569 +0100
+@@ -250,7 +250,7 @@
+
+ page_is_high = PageHighMem(page);
+ if (page_is_high)
+- local_irq_save(flags);
++ local_irq_save_nort(flags);
+
+ buf = kmap_atomic(page) + offset;
+
+@@ -271,7 +271,7 @@
+ kunmap_atomic(buf);
+
+ if (page_is_high)
+- local_irq_restore(flags);
++ local_irq_restore_nort(flags);
+
+ len -= nr_bytes;
+ }
+@@ -414,7 +414,7 @@
+ }
+
+ if ((drive->dev_flags & IDE_DFLAG_UNMASK) == 0)
+- local_irq_disable();
++ local_irq_disable_nort();
+
+ ide_set_handler(drive, &task_pio_intr, WAIT_WORSTCASE);
+
+diff -Nur linux-4.8.15.orig/drivers/infiniband/ulp/ipoib/ipoib_multicast.c linux-4.8.15/drivers/infiniband/ulp/ipoib/ipoib_multicast.c
+--- linux-4.8.15.orig/drivers/infiniband/ulp/ipoib/ipoib_multicast.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/infiniband/ulp/ipoib/ipoib_multicast.c 2017-01-01 17:07:14.299315394 +0100
+@@ -899,7 +899,7 @@
+
+ ipoib_dbg_mcast(priv, "restarting multicast task\n");
+
+- local_irq_save(flags);
++ local_irq_save_nort(flags);
+ netif_addr_lock(dev);
+ spin_lock(&priv->lock);
+
+@@ -981,7 +981,7 @@
+
+ spin_unlock(&priv->lock);
+ netif_addr_unlock(dev);
+- local_irq_restore(flags);
++ local_irq_restore_nort(flags);
+
+ /*
+ * make sure the in-flight joins have finished before we attempt
+diff -Nur linux-4.8.15.orig/drivers/input/gameport/gameport.c linux-4.8.15/drivers/input/gameport/gameport.c
+--- linux-4.8.15.orig/drivers/input/gameport/gameport.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/input/gameport/gameport.c 2017-01-01 17:07:14.343318229 +0100
+@@ -91,13 +91,13 @@
+ tx = ~0;
+
+ for (i = 0; i < 50; i++) {
+- local_irq_save(flags);
++ local_irq_save_nort(flags);
+ t1 = ktime_get_ns();
+ for (t = 0; t < 50; t++)
+ gameport_read(gameport);
+ t2 = ktime_get_ns();
+ t3 = ktime_get_ns();
+- local_irq_restore(flags);
++ local_irq_restore_nort(flags);
+ udelay(i * 10);
+ t = (t2 - t1) - (t3 - t2);
+ if (t < tx)
+@@ -124,12 +124,12 @@
+ tx = 1 << 30;
+
+ for(i = 0; i < 50; i++) {
+- local_irq_save(flags);
++ local_irq_save_nort(flags);
+ GET_TIME(t1);
+ for (t = 0; t < 50; t++) gameport_read(gameport);
+ GET_TIME(t2);
+ GET_TIME(t3);
+- local_irq_restore(flags);
++ local_irq_restore_nort(flags);
+ udelay(i * 10);
+ if ((t = DELTA(t2,t1) - DELTA(t3,t2)) < tx) tx = t;
+ }
+@@ -148,11 +148,11 @@
+ tx = 1 << 30;
+
+ for(i = 0; i < 50; i++) {
+- local_irq_save(flags);
++ local_irq_save_nort(flags);
+ t1 = rdtsc();
+ for (t = 0; t < 50; t++) gameport_read(gameport);
+ t2 = rdtsc();
+- local_irq_restore(flags);
++ local_irq_restore_nort(flags);
+ udelay(i * 10);
+ if (t2 - t1 < tx) tx = t2 - t1;
+ }
+diff -Nur linux-4.8.15.orig/drivers/iommu/amd_iommu.c linux-4.8.15/drivers/iommu/amd_iommu.c
+--- linux-4.8.15.orig/drivers/iommu/amd_iommu.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/iommu/amd_iommu.c 2017-01-01 17:07:14.403322093 +0100
+@@ -1835,10 +1835,10 @@
+ int ret;
+
+ /*
+- * Must be called with IRQs disabled. Warn here to detect early
+- * when its not.
++ * Must be called with IRQs disabled on a non RT kernel. Warn here to
++ * detect early when its not.
+ */
+- WARN_ON(!irqs_disabled());
++ WARN_ON_NONRT(!irqs_disabled());
+
+ /* lock domain */
+ spin_lock(&domain->lock);
+@@ -2006,10 +2006,10 @@
+ struct protection_domain *domain;
+
+ /*
+- * Must be called with IRQs disabled. Warn here to detect early
+- * when its not.
++ * Must be called with IRQs disabled on a non RT kernel. Warn here to
++ * detect early when its not.
+ */
+- WARN_ON(!irqs_disabled());
++ WARN_ON_NONRT(!irqs_disabled());
+
+ if (WARN_ON(!dev_data->domain))
+ return;
+diff -Nur linux-4.8.15.orig/drivers/iommu/intel-iommu.c linux-4.8.15/drivers/iommu/intel-iommu.c
+--- linux-4.8.15.orig/drivers/iommu/intel-iommu.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/iommu/intel-iommu.c 2017-01-01 17:07:14.443324672 +0100
+@@ -479,7 +479,7 @@
+ struct deferred_flush_table *tables;
+ };
+
+-DEFINE_PER_CPU(struct deferred_flush_data, deferred_flush);
++static DEFINE_PER_CPU(struct deferred_flush_data, deferred_flush);
+
+ /* bitmap for indexing intel_iommus */
+ static int g_num_of_iommus;
+@@ -3649,10 +3649,8 @@
+ struct intel_iommu *iommu;
+ struct deferred_flush_entry *entry;
+ struct deferred_flush_data *flush_data;
+- unsigned int cpuid;
+
+- cpuid = get_cpu();
+- flush_data = per_cpu_ptr(&deferred_flush, cpuid);
++ flush_data = raw_cpu_ptr(&deferred_flush);
+
+ /* Flush all CPUs' entries to avoid deferring too much. If
+ * this becomes a bottleneck, can just flush us, and rely on
+@@ -3685,8 +3683,6 @@
+ }
+ flush_data->size++;
+ spin_unlock_irqrestore(&flush_data->lock, flags);
+-
+- put_cpu();
+ }
+
+ static void intel_unmap(struct device *dev, dma_addr_t dev_addr, size_t size)
+diff -Nur linux-4.8.15.orig/drivers/iommu/iova.c linux-4.8.15/drivers/iommu/iova.c
+--- linux-4.8.15.orig/drivers/iommu/iova.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/iommu/iova.c 2017-01-01 17:07:14.455325452 +0100
+@@ -22,6 +22,7 @@
+ #include <linux/slab.h>
+ #include <linux/smp.h>
+ #include <linux/bitops.h>
++#include <linux/cpu.h>
+
+ static bool iova_rcache_insert(struct iova_domain *iovad,
+ unsigned long pfn,
+@@ -420,10 +421,8 @@
+
+ /* Try replenishing IOVAs by flushing rcache. */
+ flushed_rcache = true;
+- preempt_disable();
+ for_each_online_cpu(cpu)
+ free_cpu_cached_iovas(cpu, iovad);
+- preempt_enable();
+ goto retry;
+ }
+
+@@ -751,7 +750,7 @@
+ bool can_insert = false;
+ unsigned long flags;
+
+- cpu_rcache = get_cpu_ptr(rcache->cpu_rcaches);
++ cpu_rcache = raw_cpu_ptr(rcache->cpu_rcaches);
+ spin_lock_irqsave(&cpu_rcache->lock, flags);
+
+ if (!iova_magazine_full(cpu_rcache->loaded)) {
+@@ -781,7 +780,6 @@
+ iova_magazine_push(cpu_rcache->loaded, iova_pfn);
+
+ spin_unlock_irqrestore(&cpu_rcache->lock, flags);
+- put_cpu_ptr(rcache->cpu_rcaches);
+
+ if (mag_to_free) {
+ iova_magazine_free_pfns(mag_to_free, iovad);
+@@ -815,7 +813,7 @@
+ bool has_pfn = false;
+ unsigned long flags;
+
+- cpu_rcache = get_cpu_ptr(rcache->cpu_rcaches);
++ cpu_rcache = raw_cpu_ptr(rcache->cpu_rcaches);
+ spin_lock_irqsave(&cpu_rcache->lock, flags);
+
+ if (!iova_magazine_empty(cpu_rcache->loaded)) {
+@@ -837,7 +835,6 @@
+ iova_pfn = iova_magazine_pop(cpu_rcache->loaded, limit_pfn);
+
+ spin_unlock_irqrestore(&cpu_rcache->lock, flags);
+- put_cpu_ptr(rcache->cpu_rcaches);
+
+ return iova_pfn;
+ }
+diff -Nur linux-4.8.15.orig/drivers/leds/trigger/Kconfig linux-4.8.15/drivers/leds/trigger/Kconfig
+--- linux-4.8.15.orig/drivers/leds/trigger/Kconfig 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/leds/trigger/Kconfig 2017-01-01 17:07:14.495328021 +0100
+@@ -69,7 +69,7 @@
+
+ config LEDS_TRIGGER_CPU
+ bool "LED CPU Trigger"
+- depends on LEDS_TRIGGERS
++ depends on LEDS_TRIGGERS && !PREEMPT_RT_BASE
+ help
+ This allows LEDs to be controlled by active CPUs. This shows
+ the active CPUs across an array of LEDs so you can see which
+diff -Nur linux-4.8.15.orig/drivers/md/bcache/Kconfig linux-4.8.15/drivers/md/bcache/Kconfig
+--- linux-4.8.15.orig/drivers/md/bcache/Kconfig 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/md/bcache/Kconfig 2017-01-01 17:07:14.511329049 +0100
+@@ -1,6 +1,7 @@
+
+ config BCACHE
+ tristate "Block device as cache"
++ depends on !PREEMPT_RT_FULL
+ ---help---
+ Allows a block device to be used as cache for other devices; uses
+ a btree for indexing and the layout is optimized for SSDs.
+diff -Nur linux-4.8.15.orig/drivers/md/dm-rq.c linux-4.8.15/drivers/md/dm-rq.c
+--- linux-4.8.15.orig/drivers/md/dm-rq.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/md/dm-rq.c 2017-01-01 17:07:14.515329315 +0100
+@@ -811,7 +811,7 @@
+ /* Establish tio->ti before queuing work (map_tio_request) */
+ tio->ti = ti;
+ queue_kthread_work(&md->kworker, &tio->work);
+- BUG_ON(!irqs_disabled());
++ BUG_ON_NONRT(!irqs_disabled());
+ }
+ }
+
+diff -Nur linux-4.8.15.orig/drivers/md/raid5.c linux-4.8.15/drivers/md/raid5.c
+--- linux-4.8.15.orig/drivers/md/raid5.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/md/raid5.c 2017-01-01 17:07:14.555331893 +0100
+@@ -1928,8 +1928,9 @@
+ struct raid5_percpu *percpu;
+ unsigned long cpu;
+
+- cpu = get_cpu();
++ cpu = get_cpu_light();
+ percpu = per_cpu_ptr(conf->percpu, cpu);
++ spin_lock(&percpu->lock);
+ if (test_bit(STRIPE_OP_BIOFILL, &ops_request)) {
+ ops_run_biofill(sh);
+ overlap_clear++;
+@@ -1985,7 +1986,8 @@
+ if (test_and_clear_bit(R5_Overlap, &dev->flags))
+ wake_up(&sh->raid_conf->wait_for_overlap);
+ }
+- put_cpu();
++ spin_unlock(&percpu->lock);
++ put_cpu_light();
+ }
+
+ static struct stripe_head *alloc_stripe(struct kmem_cache *sc, gfp_t gfp,
+@@ -6438,6 +6440,7 @@
+ __func__, cpu);
+ break;
+ }
++ spin_lock_init(&per_cpu_ptr(conf->percpu, cpu)->lock);
+ }
+ put_online_cpus();
+
+diff -Nur linux-4.8.15.orig/drivers/md/raid5.h linux-4.8.15/drivers/md/raid5.h
+--- linux-4.8.15.orig/drivers/md/raid5.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/md/raid5.h 2017-01-01 17:07:14.571332922 +0100
+@@ -504,6 +504,7 @@
+ int recovery_disabled;
+ /* per cpu variables */
+ struct raid5_percpu {
++ spinlock_t lock; /* Protection for -RT */
+ struct page *spare_page; /* Used when checking P/Q in raid6 */
+ struct flex_array *scribble; /* space for constructing buffer
+ * lists and performing address
+diff -Nur linux-4.8.15.orig/drivers/misc/hwlat_detector.c linux-4.8.15/drivers/misc/hwlat_detector.c
+--- linux-4.8.15.orig/drivers/misc/hwlat_detector.c 1970-01-01 01:00:00.000000000 +0100
++++ linux-4.8.15/drivers/misc/hwlat_detector.c 2017-01-01 17:07:14.579333432 +0100
+@@ -0,0 +1,1240 @@
++/*
++ * hwlat_detector.c - A simple Hardware Latency detector.
++ *
++ * Use this module to detect large system latencies induced by the behavior of
++ * certain underlying system hardware or firmware, independent of Linux itself.
++ * The code was developed originally to detect the presence of SMIs on Intel
++ * and AMD systems, although there is no dependency upon x86 herein.
++ *
++ * The classical example usage of this module is in detecting the presence of
++ * SMIs or System Management Interrupts on Intel and AMD systems. An SMI is a
++ * somewhat special form of hardware interrupt spawned from earlier CPU debug
++ * modes in which the (BIOS/EFI/etc.) firmware arranges for the South Bridge
++ * LPC (or other device) to generate a special interrupt under certain
++ * circumstances, for example, upon expiration of a special SMI timer device,
++ * due to certain external thermal readings, on certain I/O address accesses,
++ * and other situations. An SMI hits a special CPU pin, triggers a special
++ * SMI mode (complete with special memory map), and the OS is unaware.
++ *
++ * Although certain hardware-inducing latencies are necessary (for example,
++ * a modern system often requires an SMI handler for correct thermal control
++ * and remote management) they can wreak havoc upon any OS-level performance
++ * guarantees toward low-latency, especially when the OS is not even made
++ * aware of the presence of these interrupts. For this reason, we need a
++ * somewhat brute force mechanism to detect these interrupts. In this case,
++ * we do it by hogging all of the CPU(s) for configurable timer intervals,
++ * sampling the built-in CPU timer, looking for discontiguous readings.
++ *
++ * WARNING: This implementation necessarily introduces latencies. Therefore,
++ * you should NEVER use this module in a production environment
++ * requiring any kind of low-latency performance guarantee(s).
++ *
++ * Copyright (C) 2008-2009 Jon Masters, Red Hat, Inc. <jcm@redhat.com>
++ *
++ * Includes useful feedback from Clark Williams <clark@redhat.com>
++ *
++ * This file is licensed under the terms of the GNU General Public
++ * License version 2. This program is licensed "as is" without any
++ * warranty of any kind, whether express or implied.
++ */
++
++#include <linux/module.h>
++#include <linux/init.h>
++#include <linux/ring_buffer.h>
++#include <linux/time.h>
++#include <linux/hrtimer.h>
++#include <linux/kthread.h>
++#include <linux/debugfs.h>
++#include <linux/seq_file.h>
++#include <linux/uaccess.h>
++#include <linux/version.h>
++#include <linux/delay.h>
++#include <linux/slab.h>
++#include <linux/trace_clock.h>
++
++#define BUF_SIZE_DEFAULT 262144UL /* 8K*(sizeof(entry)) */
++#define BUF_FLAGS (RB_FL_OVERWRITE) /* no block on full */
++#define U64STR_SIZE 22 /* 20 digits max */
++
++#define VERSION "1.0.0"
++#define BANNER "hwlat_detector: "
++#define DRVNAME "hwlat_detector"
++#define DEFAULT_SAMPLE_WINDOW 1000000 /* 1s */
++#define DEFAULT_SAMPLE_WIDTH 500000 /* 0.5s */
++#define DEFAULT_LAT_THRESHOLD 10 /* 10us */
++
++/* Module metadata */
++
++MODULE_LICENSE("GPL");
++MODULE_AUTHOR("Jon Masters <jcm@redhat.com>");
++MODULE_DESCRIPTION("A simple hardware latency detector");
++MODULE_VERSION(VERSION);
++
++/* Module parameters */
++
++static int debug;
++static int enabled;
++static int threshold;
++
++module_param(debug, int, 0); /* enable debug */
++module_param(enabled, int, 0); /* enable detector */
++module_param(threshold, int, 0); /* latency threshold */
++
++/* Buffering and sampling */
++
++static struct ring_buffer *ring_buffer; /* sample buffer */
++static DEFINE_MUTEX(ring_buffer_mutex); /* lock changes */
++static unsigned long buf_size = BUF_SIZE_DEFAULT;
++static struct task_struct *kthread; /* sampling thread */
++
++/* DebugFS filesystem entries */
++
++static struct dentry *debug_dir; /* debugfs directory */
++static struct dentry *debug_max; /* maximum TSC delta */
++static struct dentry *debug_count; /* total detect count */
++static struct dentry *debug_sample_width; /* sample width us */
++static struct dentry *debug_sample_window; /* sample window us */
++static struct dentry *debug_sample; /* raw samples us */
++static struct dentry *debug_threshold; /* threshold us */
++static struct dentry *debug_enable; /* enable/disable */
++
++/* Individual samples and global state */
++
++struct sample; /* latency sample */
++struct data; /* Global state */
++
++/* Sampling functions */
++static int __buffer_add_sample(struct sample *sample);
++static struct sample *buffer_get_sample(struct sample *sample);
++
++/* Threading and state */
++static int kthread_fn(void *unused);
++static int start_kthread(void);
++static int stop_kthread(void);
++static void __reset_stats(void);
++static int init_stats(void);
++
++/* Debugfs interface */
++static ssize_t simple_data_read(struct file *filp, char __user *ubuf,
++ size_t cnt, loff_t *ppos, const u64 *entry);
++static ssize_t simple_data_write(struct file *filp, const char __user *ubuf,
++ size_t cnt, loff_t *ppos, u64 *entry);
++static int debug_sample_fopen(struct inode *inode, struct file *filp);
++static ssize_t debug_sample_fread(struct file *filp, char __user *ubuf,
++ size_t cnt, loff_t *ppos);
++static int debug_sample_release(struct inode *inode, struct file *filp);
++static int debug_enable_fopen(struct inode *inode, struct file *filp);
++static ssize_t debug_enable_fread(struct file *filp, char __user *ubuf,
++ size_t cnt, loff_t *ppos);
++static ssize_t debug_enable_fwrite(struct file *file,
++ const char __user *user_buffer,
++ size_t user_size, loff_t *offset);
++
++/* Initialization functions */
++static int init_debugfs(void);
++static void free_debugfs(void);
++static int detector_init(void);
++static void detector_exit(void);
++
++/* Individual latency samples are stored here when detected and packed into
++ * the ring_buffer circular buffer, where they are overwritten when
++ * more than buf_size/sizeof(sample) samples are received. */
++struct sample {
++ u64 seqnum; /* unique sequence */
++ u64 duration; /* ktime delta */
++ u64 outer_duration; /* ktime delta (outer loop) */
++ struct timespec timestamp; /* wall time */
++ unsigned long lost;
++};
++
++/* keep the global state somewhere. */
++static struct data {
++
++ struct mutex lock; /* protect changes */
++
++ u64 count; /* total since reset */
++ u64 max_sample; /* max hardware latency */
++ u64 threshold; /* sample threshold level */
++
++ u64 sample_window; /* total sampling window (on+off) */
++ u64 sample_width; /* active sampling portion of window */
++
++ atomic_t sample_open; /* whether the sample file is open */
++
++ wait_queue_head_t wq; /* waitqeue for new sample values */
++
++} data;
++
++/**
++ * __buffer_add_sample - add a new latency sample recording to the ring buffer
++ * @sample: The new latency sample value
++ *
++ * This receives a new latency sample and records it in a global ring buffer.
++ * No additional locking is used in this case.
++ */
++static int __buffer_add_sample(struct sample *sample)
++{
++ return ring_buffer_write(ring_buffer,
++ sizeof(struct sample), sample);
++}
++
++/**
++ * buffer_get_sample - remove a hardware latency sample from the ring buffer
++ * @sample: Pre-allocated storage for the sample
++ *
++ * This retrieves a hardware latency sample from the global circular buffer
++ */
++static struct sample *buffer_get_sample(struct sample *sample)
++{
++ struct ring_buffer_event *e = NULL;
++ struct sample *s = NULL;
++ unsigned int cpu = 0;
++
++ if (!sample)
++ return NULL;
++
++ mutex_lock(&ring_buffer_mutex);
++ for_each_online_cpu(cpu) {
++ e = ring_buffer_consume(ring_buffer, cpu, NULL, &sample->lost);
++ if (e)
++ break;
++ }
++
++ if (e) {
++ s = ring_buffer_event_data(e);
++ memcpy(sample, s, sizeof(struct sample));
++ } else
++ sample = NULL;
++ mutex_unlock(&ring_buffer_mutex);
++
++ return sample;
++}
++
++#ifndef CONFIG_TRACING
++#define time_type ktime_t
++#define time_get() ktime_get()
++#define time_to_us(x) ktime_to_us(x)
++#define time_sub(a, b) ktime_sub(a, b)
++#define init_time(a, b) (a).tv64 = b
++#define time_u64(a) ((a).tv64)
++#else
++#define time_type u64
++#define time_get() trace_clock_local()
++#define time_to_us(x) div_u64(x, 1000)
++#define time_sub(a, b) ((a) - (b))
++#define init_time(a, b) (a = b)
++#define time_u64(a) a
++#endif
++/**
++ * get_sample - sample the CPU TSC and look for likely hardware latencies
++ *
++ * Used to repeatedly capture the CPU TSC (or similar), looking for potential
++ * hardware-induced latency. Called with interrupts disabled and with
++ * data.lock held.
++ */
++static int get_sample(void)
++{
++ time_type start, t1, t2, last_t2;
++ s64 diff, total = 0;
++ u64 sample = 0;
++ u64 outer_sample = 0;
++ int ret = -1;
++
++ init_time(last_t2, 0);
++ start = time_get(); /* start timestamp */
++
++ do {
++
++ t1 = time_get(); /* we'll look for a discontinuity */
++ t2 = time_get();
++
++ if (time_u64(last_t2)) {
++ /* Check the delta from outer loop (t2 to next t1) */
++ diff = time_to_us(time_sub(t1, last_t2));
++ /* This shouldn't happen */
++ if (diff < 0) {
++ pr_err(BANNER "time running backwards\n");
++ goto out;
++ }
++ if (diff > outer_sample)
++ outer_sample = diff;
++ }
++ last_t2 = t2;
++
++ total = time_to_us(time_sub(t2, start)); /* sample width */
++
++ /* This checks the inner loop (t1 to t2) */
++ diff = time_to_us(time_sub(t2, t1)); /* current diff */
++
++ /* This shouldn't happen */
++ if (diff < 0) {
++ pr_err(BANNER "time running backwards\n");
++ goto out;
++ }
++
++ if (diff > sample)
++ sample = diff; /* only want highest value */
++
++ } while (total <= data.sample_width);
++
++ ret = 0;
++
++ /* If we exceed the threshold value, we have found a hardware latency */
++ if (sample > data.threshold || outer_sample > data.threshold) {
++ struct sample s;
++
++ ret = 1;
++
++ data.count++;
++ s.seqnum = data.count;
++ s.duration = sample;
++ s.outer_duration = outer_sample;
++ s.timestamp = CURRENT_TIME;
++ __buffer_add_sample(&s);
++
++ /* Keep a running maximum ever recorded hardware latency */
++ if (sample > data.max_sample)
++ data.max_sample = sample;
++ }
++
++out:
++ return ret;
++}
++
++/*
++ * kthread_fn - The CPU time sampling/hardware latency detection kernel thread
++ * @unused: A required part of the kthread API.
++ *
++ * Used to periodically sample the CPU TSC via a call to get_sample. We
++ * disable interrupts, which does (intentionally) introduce latency since we
++ * need to ensure nothing else might be running (and thus pre-empting).
++ * Obviously this should never be used in production environments.
++ *
++ * Currently this runs on which ever CPU it was scheduled on, but most
++ * real-worald hardware latency situations occur across several CPUs,
++ * but we might later generalize this if we find there are any actualy
++ * systems with alternate SMI delivery or other hardware latencies.
++ */
++static int kthread_fn(void *unused)
++{
++ int ret;
++ u64 interval;
++
++ while (!kthread_should_stop()) {
++
++ mutex_lock(&data.lock);
++
++ local_irq_disable();
++ ret = get_sample();
++ local_irq_enable();
++
++ if (ret > 0)
++ wake_up(&data.wq); /* wake up reader(s) */
++
++ interval = data.sample_window - data.sample_width;
++ do_div(interval, USEC_PER_MSEC); /* modifies interval value */
++
++ mutex_unlock(&data.lock);
++
++ if (msleep_interruptible(interval))
++ break;
++ }
++
++ return 0;
++}
++
++/**
++ * start_kthread - Kick off the hardware latency sampling/detector kthread
++ *
++ * This starts a kernel thread that will sit and sample the CPU timestamp
++ * counter (TSC or similar) and look for potential hardware latencies.
++ */
++static int start_kthread(void)
++{
++ kthread = kthread_run(kthread_fn, NULL,
++ DRVNAME);
++ if (IS_ERR(kthread)) {
++ pr_err(BANNER "could not start sampling thread\n");
++ enabled = 0;
++ return -ENOMEM;
++ }
++
++ return 0;
++}
++
++/**
++ * stop_kthread - Inform the hardware latency samping/detector kthread to stop
++ *
++ * This kicks the running hardware latency sampling/detector kernel thread and
++ * tells it to stop sampling now. Use this on unload and at system shutdown.
++ */
++static int stop_kthread(void)
++{
++ int ret;
++
++ ret = kthread_stop(kthread);
++
++ return ret;
++}
++
++/**
++ * __reset_stats - Reset statistics for the hardware latency detector
++ *
++ * We use data to store various statistics and global state. We call this
++ * function in order to reset those when "enable" is toggled on or off, and
++ * also at initialization. Should be called with data.lock held.
++ */
++static void __reset_stats(void)
++{
++ data.count = 0;
++ data.max_sample = 0;
++ ring_buffer_reset(ring_buffer); /* flush out old sample entries */
++}
++
++/**
++ * init_stats - Setup global state statistics for the hardware latency detector
++ *
++ * We use data to store various statistics and global state. We also use
++ * a global ring buffer (ring_buffer) to keep raw samples of detected hardware
++ * induced system latencies. This function initializes these structures and
++ * allocates the global ring buffer also.
++ */
++static int init_stats(void)
++{
++ int ret = -ENOMEM;
++
++ mutex_init(&data.lock);
++ init_waitqueue_head(&data.wq);
++ atomic_set(&data.sample_open, 0);
++
++ ring_buffer = ring_buffer_alloc(buf_size, BUF_FLAGS);
++
++ if (WARN(!ring_buffer, KERN_ERR BANNER
++ "failed to allocate ring buffer!\n"))
++ goto out;
++
++ __reset_stats();
++ data.threshold = threshold ?: DEFAULT_LAT_THRESHOLD; /* threshold us */
++ data.sample_window = DEFAULT_SAMPLE_WINDOW; /* window us */
++ data.sample_width = DEFAULT_SAMPLE_WIDTH; /* width us */
++
++ ret = 0;
++
++out:
++ return ret;
++
++}
++
++/*
++ * simple_data_read - Wrapper read function for global state debugfs entries
++ * @filp: The active open file structure for the debugfs "file"
++ * @ubuf: The userspace provided buffer to read value into
++ * @cnt: The maximum number of bytes to read
++ * @ppos: The current "file" position
++ * @entry: The entry to read from
++ *
++ * This function provides a generic read implementation for the global state
++ * "data" structure debugfs filesystem entries. It would be nice to use
++ * simple_attr_read directly, but we need to make sure that the data.lock
++ * is held during the actual read.
++ */
++static ssize_t simple_data_read(struct file *filp, char __user *ubuf,
++ size_t cnt, loff_t *ppos, const u64 *entry)
++{
++ char buf[U64STR_SIZE];
++ u64 val = 0;
++ int len = 0;
++
++ memset(buf, 0, sizeof(buf));
++
++ if (!entry)
++ return -EFAULT;
++
++ mutex_lock(&data.lock);
++ val = *entry;
++ mutex_unlock(&data.lock);
++
++ len = snprintf(buf, sizeof(buf), "%llu\n", (unsigned long long)val);
++
++ return simple_read_from_buffer(ubuf, cnt, ppos, buf, len);
++
++}
++
++/*
++ * simple_data_write - Wrapper write function for global state debugfs entries
++ * @filp: The active open file structure for the debugfs "file"
++ * @ubuf: The userspace provided buffer to write value from
++ * @cnt: The maximum number of bytes to write
++ * @ppos: The current "file" position
++ * @entry: The entry to write to
++ *
++ * This function provides a generic write implementation for the global state
++ * "data" structure debugfs filesystem entries. It would be nice to use
++ * simple_attr_write directly, but we need to make sure that the data.lock
++ * is held during the actual write.
++ */
++static ssize_t simple_data_write(struct file *filp, const char __user *ubuf,
++ size_t cnt, loff_t *ppos, u64 *entry)
++{
++ char buf[U64STR_SIZE];
++ int csize = min(cnt, sizeof(buf));
++ u64 val = 0;
++ int err = 0;
++
++ memset(buf, '\0', sizeof(buf));
++ if (copy_from_user(buf, ubuf, csize))
++ return -EFAULT;
++
++ buf[U64STR_SIZE-1] = '\0'; /* just in case */
++ err = kstrtoull(buf, 10, &val);
++ if (err)
++ return -EINVAL;
++
++ mutex_lock(&data.lock);
++ *entry = val;
++ mutex_unlock(&data.lock);
++
++ return csize;
++}
++
++/**
++ * debug_count_fopen - Open function for "count" debugfs entry
++ * @inode: The in-kernel inode representation of the debugfs "file"
++ * @filp: The active open file structure for the debugfs "file"
++ *
++ * This function provides an open implementation for the "count" debugfs
++ * interface to the hardware latency detector.
++ */
++static int debug_count_fopen(struct inode *inode, struct file *filp)
++{
++ return 0;
++}
++
++/**
++ * debug_count_fread - Read function for "count" debugfs entry
++ * @filp: The active open file structure for the debugfs "file"
++ * @ubuf: The userspace provided buffer to read value into
++ * @cnt: The maximum number of bytes to read
++ * @ppos: The current "file" position
++ *
++ * This function provides a read implementation for the "count" debugfs
++ * interface to the hardware latency detector. Can be used to read the
++ * number of latency readings exceeding the configured threshold since
++ * the detector was last reset (e.g. by writing a zero into "count").
++ */
++static ssize_t debug_count_fread(struct file *filp, char __user *ubuf,
++ size_t cnt, loff_t *ppos)
++{
++ return simple_data_read(filp, ubuf, cnt, ppos, &data.count);
++}
++
++/**
++ * debug_count_fwrite - Write function for "count" debugfs entry
++ * @filp: The active open file structure for the debugfs "file"
++ * @ubuf: The user buffer that contains the value to write
++ * @cnt: The maximum number of bytes to write to "file"
++ * @ppos: The current position in the debugfs "file"
++ *
++ * This function provides a write implementation for the "count" debugfs
++ * interface to the hardware latency detector. Can be used to write a
++ * desired value, especially to zero the total count.
++ */
++static ssize_t debug_count_fwrite(struct file *filp,
++ const char __user *ubuf,
++ size_t cnt,
++ loff_t *ppos)
++{
++ return simple_data_write(filp, ubuf, cnt, ppos, &data.count);
++}
++
++/**
++ * debug_enable_fopen - Dummy open function for "enable" debugfs interface
++ * @inode: The in-kernel inode representation of the debugfs "file"
++ * @filp: The active open file structure for the debugfs "file"
++ *
++ * This function provides an open implementation for the "enable" debugfs
++ * interface to the hardware latency detector.
++ */
++static int debug_enable_fopen(struct inode *inode, struct file *filp)
++{
++ return 0;
++}
++
++/**
++ * debug_enable_fread - Read function for "enable" debugfs interface
++ * @filp: The active open file structure for the debugfs "file"
++ * @ubuf: The userspace provided buffer to read value into
++ * @cnt: The maximum number of bytes to read
++ * @ppos: The current "file" position
++ *
++ * This function provides a read implementation for the "enable" debugfs
++ * interface to the hardware latency detector. Can be used to determine
++ * whether the detector is currently enabled ("0\n" or "1\n" returned).
++ */
++static ssize_t debug_enable_fread(struct file *filp, char __user *ubuf,
++ size_t cnt, loff_t *ppos)
++{
++ char buf[4];
++
++ if ((cnt < sizeof(buf)) || (*ppos))
++ return 0;
++
++ buf[0] = enabled ? '1' : '0';
++ buf[1] = '\n';
++ buf[2] = '\0';
++ if (copy_to_user(ubuf, buf, strlen(buf)))
++ return -EFAULT;
++ return *ppos = strlen(buf);
++}
++
++/**
++ * debug_enable_fwrite - Write function for "enable" debugfs interface
++ * @filp: The active open file structure for the debugfs "file"
++ * @ubuf: The user buffer that contains the value to write
++ * @cnt: The maximum number of bytes to write to "file"
++ * @ppos: The current position in the debugfs "file"
++ *
++ * This function provides a write implementation for the "enable" debugfs
++ * interface to the hardware latency detector. Can be used to enable or
++ * disable the detector, which will have the side-effect of possibly
++ * also resetting the global stats and kicking off the measuring
++ * kthread (on an enable) or the converse (upon a disable).
++ */
++static ssize_t debug_enable_fwrite(struct file *filp,
++ const char __user *ubuf,
++ size_t cnt,
++ loff_t *ppos)
++{
++ char buf[4];
++ int csize = min(cnt, sizeof(buf));
++ long val = 0;
++ int err = 0;
++
++ memset(buf, '\0', sizeof(buf));
++ if (copy_from_user(buf, ubuf, csize))
++ return -EFAULT;
++
++ buf[sizeof(buf)-1] = '\0'; /* just in case */
++ err = kstrtoul(buf, 10, &val);
++ if (err)
++ return -EINVAL;
++
++ if (val) {
++ if (enabled)
++ goto unlock;
++ enabled = 1;
++ __reset_stats();
++ if (start_kthread())
++ return -EFAULT;
++ } else {
++ if (!enabled)
++ goto unlock;
++ enabled = 0;
++ err = stop_kthread();
++ if (err) {
++ pr_err(BANNER "cannot stop kthread\n");
++ return -EFAULT;
++ }
++ wake_up(&data.wq); /* reader(s) should return */
++ }
++unlock:
++ return csize;
++}
++
++/**
++ * debug_max_fopen - Open function for "max" debugfs entry
++ * @inode: The in-kernel inode representation of the debugfs "file"
++ * @filp: The active open file structure for the debugfs "file"
++ *
++ * This function provides an open implementation for the "max" debugfs
++ * interface to the hardware latency detector.
++ */
++static int debug_max_fopen(struct inode *inode, struct file *filp)
++{
++ return 0;
++}
++
++/**
++ * debug_max_fread - Read function for "max" debugfs entry
++ * @filp: The active open file structure for the debugfs "file"
++ * @ubuf: The userspace provided buffer to read value into
++ * @cnt: The maximum number of bytes to read
++ * @ppos: The current "file" position
++ *
++ * This function provides a read implementation for the "max" debugfs
++ * interface to the hardware latency detector. Can be used to determine
++ * the maximum latency value observed since it was last reset.
++ */
++static ssize_t debug_max_fread(struct file *filp, char __user *ubuf,
++ size_t cnt, loff_t *ppos)
++{
++ return simple_data_read(filp, ubuf, cnt, ppos, &data.max_sample);
++}
++
++/**
++ * debug_max_fwrite - Write function for "max" debugfs entry
++ * @filp: The active open file structure for the debugfs "file"
++ * @ubuf: The user buffer that contains the value to write
++ * @cnt: The maximum number of bytes to write to "file"
++ * @ppos: The current position in the debugfs "file"
++ *
++ * This function provides a write implementation for the "max" debugfs
++ * interface to the hardware latency detector. Can be used to reset the
++ * maximum or set it to some other desired value - if, then, subsequent
++ * measurements exceed this value, the maximum will be updated.
++ */
++static ssize_t debug_max_fwrite(struct file *filp,
++ const char __user *ubuf,
++ size_t cnt,
++ loff_t *ppos)
++{
++ return simple_data_write(filp, ubuf, cnt, ppos, &data.max_sample);
++}
++
++
++/**
++ * debug_sample_fopen - An open function for "sample" debugfs interface
++ * @inode: The in-kernel inode representation of this debugfs "file"
++ * @filp: The active open file structure for the debugfs "file"
++ *
++ * This function handles opening the "sample" file within the hardware
++ * latency detector debugfs directory interface. This file is used to read
++ * raw samples from the global ring_buffer and allows the user to see a
++ * running latency history. Can be opened blocking or non-blocking,
++ * affecting whether it behaves as a buffer read pipe, or does not.
++ * Implements simple locking to prevent multiple simultaneous use.
++ */
++static int debug_sample_fopen(struct inode *inode, struct file *filp)
++{
++ if (!atomic_add_unless(&data.sample_open, 1, 1))
++ return -EBUSY;
++ else
++ return 0;
++}
++
++/**
++ * debug_sample_fread - A read function for "sample" debugfs interface
++ * @filp: The active open file structure for the debugfs "file"
++ * @ubuf: The user buffer that will contain the samples read
++ * @cnt: The maximum bytes to read from the debugfs "file"
++ * @ppos: The current position in the debugfs "file"
++ *
++ * This function handles reading from the "sample" file within the hardware
++ * latency detector debugfs directory interface. This file is used to read
++ * raw samples from the global ring_buffer and allows the user to see a
++ * running latency history. By default this will block pending a new
++ * value written into the sample buffer, unless there are already a
++ * number of value(s) waiting in the buffer, or the sample file was
++ * previously opened in a non-blocking mode of operation.
++ */
++static ssize_t debug_sample_fread(struct file *filp, char __user *ubuf,
++ size_t cnt, loff_t *ppos)
++{
++ int len = 0;
++ char buf[64];
++ struct sample *sample = NULL;
++
++ if (!enabled)
++ return 0;
++
++ sample = kzalloc(sizeof(struct sample), GFP_KERNEL);
++ if (!sample)
++ return -ENOMEM;
++
++ while (!buffer_get_sample(sample)) {
++
++ DEFINE_WAIT(wait);
++
++ if (filp->f_flags & O_NONBLOCK) {
++ len = -EAGAIN;
++ goto out;
++ }
++
++ prepare_to_wait(&data.wq, &wait, TASK_INTERRUPTIBLE);
++ schedule();
++ finish_wait(&data.wq, &wait);
++
++ if (signal_pending(current)) {
++ len = -EINTR;
++ goto out;
++ }
++
++ if (!enabled) { /* enable was toggled */
++ len = 0;
++ goto out;
++ }
++ }
++
++ len = snprintf(buf, sizeof(buf), "%010lu.%010lu\t%llu\t%llu\n",
++ sample->timestamp.tv_sec,
++ sample->timestamp.tv_nsec,
++ sample->duration,
++ sample->outer_duration);
++
++
++ /* handling partial reads is more trouble than it's worth */
++ if (len > cnt)
++ goto out;
++
++ if (copy_to_user(ubuf, buf, len))
++ len = -EFAULT;
++
++out:
++ kfree(sample);
++ return len;
++}
++
++/**
++ * debug_sample_release - Release function for "sample" debugfs interface
++ * @inode: The in-kernel inode represenation of the debugfs "file"
++ * @filp: The active open file structure for the debugfs "file"
++ *
++ * This function completes the close of the debugfs interface "sample" file.
++ * Frees the sample_open "lock" so that other users may open the interface.
++ */
++static int debug_sample_release(struct inode *inode, struct file *filp)
++{
++ atomic_dec(&data.sample_open);
++
++ return 0;
++}
++
++/**
++ * debug_threshold_fopen - Open function for "threshold" debugfs entry
++ * @inode: The in-kernel inode representation of the debugfs "file"
++ * @filp: The active open file structure for the debugfs "file"
++ *
++ * This function provides an open implementation for the "threshold" debugfs
++ * interface to the hardware latency detector.
++ */
++static int debug_threshold_fopen(struct inode *inode, struct file *filp)
++{
++ return 0;
++}
++
++/**
++ * debug_threshold_fread - Read function for "threshold" debugfs entry
++ * @filp: The active open file structure for the debugfs "file"
++ * @ubuf: The userspace provided buffer to read value into
++ * @cnt: The maximum number of bytes to read
++ * @ppos: The current "file" position
++ *
++ * This function provides a read implementation for the "threshold" debugfs
++ * interface to the hardware latency detector. It can be used to determine
++ * the current threshold level at which a latency will be recorded in the
++ * global ring buffer, typically on the order of 10us.
++ */
++static ssize_t debug_threshold_fread(struct file *filp, char __user *ubuf,
++ size_t cnt, loff_t *ppos)
++{
++ return simple_data_read(filp, ubuf, cnt, ppos, &data.threshold);
++}
++
++/**
++ * debug_threshold_fwrite - Write function for "threshold" debugfs entry
++ * @filp: The active open file structure for the debugfs "file"
++ * @ubuf: The user buffer that contains the value to write
++ * @cnt: The maximum number of bytes to write to "file"
++ * @ppos: The current position in the debugfs "file"
++ *
++ * This function provides a write implementation for the "threshold" debugfs
++ * interface to the hardware latency detector. It can be used to configure
++ * the threshold level at which any subsequently detected latencies will
++ * be recorded into the global ring buffer.
++ */
++static ssize_t debug_threshold_fwrite(struct file *filp,
++ const char __user *ubuf,
++ size_t cnt,
++ loff_t *ppos)
++{
++ int ret;
++
++ ret = simple_data_write(filp, ubuf, cnt, ppos, &data.threshold);
++
++ if (enabled)
++ wake_up_process(kthread);
++
++ return ret;
++}
++
++/**
++ * debug_width_fopen - Open function for "width" debugfs entry
++ * @inode: The in-kernel inode representation of the debugfs "file"
++ * @filp: The active open file structure for the debugfs "file"
++ *
++ * This function provides an open implementation for the "width" debugfs
++ * interface to the hardware latency detector.
++ */
++static int debug_width_fopen(struct inode *inode, struct file *filp)
++{
++ return 0;
++}
++
++/**
++ * debug_width_fread - Read function for "width" debugfs entry
++ * @filp: The active open file structure for the debugfs "file"
++ * @ubuf: The userspace provided buffer to read value into
++ * @cnt: The maximum number of bytes to read
++ * @ppos: The current "file" position
++ *
++ * This function provides a read implementation for the "width" debugfs
++ * interface to the hardware latency detector. It can be used to determine
++ * for how many us of the total window us we will actively sample for any
++ * hardware-induced latecy periods. Obviously, it is not possible to
++ * sample constantly and have the system respond to a sample reader, or,
++ * worse, without having the system appear to have gone out to lunch.
++ */
++static ssize_t debug_width_fread(struct file *filp, char __user *ubuf,
++ size_t cnt, loff_t *ppos)
++{
++ return simple_data_read(filp, ubuf, cnt, ppos, &data.sample_width);
++}
++
++/**
++ * debug_width_fwrite - Write function for "width" debugfs entry
++ * @filp: The active open file structure for the debugfs "file"
++ * @ubuf: The user buffer that contains the value to write
++ * @cnt: The maximum number of bytes to write to "file"
++ * @ppos: The current position in the debugfs "file"
++ *
++ * This function provides a write implementation for the "width" debugfs
++ * interface to the hardware latency detector. It can be used to configure
++ * for how many us of the total window us we will actively sample for any
++ * hardware-induced latency periods. Obviously, it is not possible to
++ * sample constantly and have the system respond to a sample reader, or,
++ * worse, without having the system appear to have gone out to lunch. It
++ * is enforced that width is less that the total window size.
++ */
++static ssize_t debug_width_fwrite(struct file *filp,
++ const char __user *ubuf,
++ size_t cnt,
++ loff_t *ppos)
++{
++ char buf[U64STR_SIZE];
++ int csize = min(cnt, sizeof(buf));
++ u64 val = 0;
++ int err = 0;
++
++ memset(buf, '\0', sizeof(buf));
++ if (copy_from_user(buf, ubuf, csize))
++ return -EFAULT;
++
++ buf[U64STR_SIZE-1] = '\0'; /* just in case */
++ err = kstrtoull(buf, 10, &val);
++ if (err)
++ return -EINVAL;
++
++ mutex_lock(&data.lock);
++ if (val < data.sample_window)
++ data.sample_width = val;
++ else {
++ mutex_unlock(&data.lock);
++ return -EINVAL;
++ }
++ mutex_unlock(&data.lock);
++
++ if (enabled)
++ wake_up_process(kthread);
++
++ return csize;
++}
++
++/**
++ * debug_window_fopen - Open function for "window" debugfs entry
++ * @inode: The in-kernel inode representation of the debugfs "file"
++ * @filp: The active open file structure for the debugfs "file"
++ *
++ * This function provides an open implementation for the "window" debugfs
++ * interface to the hardware latency detector. The window is the total time
++ * in us that will be considered one sample period. Conceptually, windows
++ * occur back-to-back and contain a sample width period during which
++ * actual sampling occurs.
++ */
++static int debug_window_fopen(struct inode *inode, struct file *filp)
++{
++ return 0;
++}
++
++/**
++ * debug_window_fread - Read function for "window" debugfs entry
++ * @filp: The active open file structure for the debugfs "file"
++ * @ubuf: The userspace provided buffer to read value into
++ * @cnt: The maximum number of bytes to read
++ * @ppos: The current "file" position
++ *
++ * This function provides a read implementation for the "window" debugfs
++ * interface to the hardware latency detector. The window is the total time
++ * in us that will be considered one sample period. Conceptually, windows
++ * occur back-to-back and contain a sample width period during which
++ * actual sampling occurs. Can be used to read the total window size.
++ */
++static ssize_t debug_window_fread(struct file *filp, char __user *ubuf,
++ size_t cnt, loff_t *ppos)
++{
++ return simple_data_read(filp, ubuf, cnt, ppos, &data.sample_window);
++}
++
++/**
++ * debug_window_fwrite - Write function for "window" debugfs entry
++ * @filp: The active open file structure for the debugfs "file"
++ * @ubuf: The user buffer that contains the value to write
++ * @cnt: The maximum number of bytes to write to "file"
++ * @ppos: The current position in the debugfs "file"
++ *
++ * This function provides a write implementation for the "window" debufds
++ * interface to the hardware latency detetector. The window is the total time
++ * in us that will be considered one sample period. Conceptually, windows
++ * occur back-to-back and contain a sample width period during which
++ * actual sampling occurs. Can be used to write a new total window size. It
++ * is enfoced that any value written must be greater than the sample width
++ * size, or an error results.
++ */
++static ssize_t debug_window_fwrite(struct file *filp,
++ const char __user *ubuf,
++ size_t cnt,
++ loff_t *ppos)
++{
++ char buf[U64STR_SIZE];
++ int csize = min(cnt, sizeof(buf));
++ u64 val = 0;
++ int err = 0;
++
++ memset(buf, '\0', sizeof(buf));
++ if (copy_from_user(buf, ubuf, csize))
++ return -EFAULT;
++
++ buf[U64STR_SIZE-1] = '\0'; /* just in case */
++ err = kstrtoull(buf, 10, &val);
++ if (err)
++ return -EINVAL;
++
++ mutex_lock(&data.lock);
++ if (data.sample_width < val)
++ data.sample_window = val;
++ else {
++ mutex_unlock(&data.lock);
++ return -EINVAL;
++ }
++ mutex_unlock(&data.lock);
++
++ return csize;
++}
++
++/*
++ * Function pointers for the "count" debugfs file operations
++ */
++static const struct file_operations count_fops = {
++ .open = debug_count_fopen,
++ .read = debug_count_fread,
++ .write = debug_count_fwrite,
++ .owner = THIS_MODULE,
++};
++
++/*
++ * Function pointers for the "enable" debugfs file operations
++ */
++static const struct file_operations enable_fops = {
++ .open = debug_enable_fopen,
++ .read = debug_enable_fread,
++ .write = debug_enable_fwrite,
++ .owner = THIS_MODULE,
++};
++
++/*
++ * Function pointers for the "max" debugfs file operations
++ */
++static const struct file_operations max_fops = {
++ .open = debug_max_fopen,
++ .read = debug_max_fread,
++ .write = debug_max_fwrite,
++ .owner = THIS_MODULE,
++};
++
++/*
++ * Function pointers for the "sample" debugfs file operations
++ */
++static const struct file_operations sample_fops = {
++ .open = debug_sample_fopen,
++ .read = debug_sample_fread,
++ .release = debug_sample_release,
++ .owner = THIS_MODULE,
++};
++
++/*
++ * Function pointers for the "threshold" debugfs file operations
++ */
++static const struct file_operations threshold_fops = {
++ .open = debug_threshold_fopen,
++ .read = debug_threshold_fread,
++ .write = debug_threshold_fwrite,
++ .owner = THIS_MODULE,
++};
++
++/*
++ * Function pointers for the "width" debugfs file operations
++ */
++static const struct file_operations width_fops = {
++ .open = debug_width_fopen,
++ .read = debug_width_fread,
++ .write = debug_width_fwrite,
++ .owner = THIS_MODULE,
++};
++
++/*
++ * Function pointers for the "window" debugfs file operations
++ */
++static const struct file_operations window_fops = {
++ .open = debug_window_fopen,
++ .read = debug_window_fread,
++ .write = debug_window_fwrite,
++ .owner = THIS_MODULE,
++};
++
++/**
++ * init_debugfs - A function to initialize the debugfs interface files
++ *
++ * This function creates entries in debugfs for "hwlat_detector", including
++ * files to read values from the detector, current samples, and the
++ * maximum sample that has been captured since the hardware latency
++ * dectector was started.
++ */
++static int init_debugfs(void)
++{
++ int ret = -ENOMEM;
++
++ debug_dir = debugfs_create_dir(DRVNAME, NULL);
++ if (!debug_dir)
++ goto err_debug_dir;
++
++ debug_sample = debugfs_create_file("sample", 0444,
++ debug_dir, NULL,
++ &sample_fops);
++ if (!debug_sample)
++ goto err_sample;
++
++ debug_count = debugfs_create_file("count", 0444,
++ debug_dir, NULL,
++ &count_fops);
++ if (!debug_count)
++ goto err_count;
++
++ debug_max = debugfs_create_file("max", 0444,
++ debug_dir, NULL,
++ &max_fops);
++ if (!debug_max)
++ goto err_max;
++
++ debug_sample_window = debugfs_create_file("window", 0644,
++ debug_dir, NULL,
++ &window_fops);
++ if (!debug_sample_window)
++ goto err_window;
++
++ debug_sample_width = debugfs_create_file("width", 0644,
++ debug_dir, NULL,
++ &width_fops);
++ if (!debug_sample_width)
++ goto err_width;
++
++ debug_threshold = debugfs_create_file("threshold", 0644,
++ debug_dir, NULL,
++ &threshold_fops);
++ if (!debug_threshold)
++ goto err_threshold;
++
++ debug_enable = debugfs_create_file("enable", 0644,
++ debug_dir, &enabled,
++ &enable_fops);
++ if (!debug_enable)
++ goto err_enable;
++
++ else {
++ ret = 0;
++ goto out;
++ }
++
++err_enable:
++ debugfs_remove(debug_threshold);
++err_threshold:
++ debugfs_remove(debug_sample_width);
++err_width:
++ debugfs_remove(debug_sample_window);
++err_window:
++ debugfs_remove(debug_max);
++err_max:
++ debugfs_remove(debug_count);
++err_count:
++ debugfs_remove(debug_sample);
++err_sample:
++ debugfs_remove(debug_dir);
++err_debug_dir:
++out:
++ return ret;
++}
++
++/**
++ * free_debugfs - A function to cleanup the debugfs file interface
++ */
++static void free_debugfs(void)
++{
++ /* could also use a debugfs_remove_recursive */
++ debugfs_remove(debug_enable);
++ debugfs_remove(debug_threshold);
++ debugfs_remove(debug_sample_width);
++ debugfs_remove(debug_sample_window);
++ debugfs_remove(debug_max);
++ debugfs_remove(debug_count);
++ debugfs_remove(debug_sample);
++ debugfs_remove(debug_dir);
++}
++
++/**
++ * detector_init - Standard module initialization code
++ */
++static int detector_init(void)
++{
++ int ret = -ENOMEM;
++
++ pr_info(BANNER "version %s\n", VERSION);
++
++ ret = init_stats();
++ if (ret)
++ goto out;
++
++ ret = init_debugfs();
++ if (ret)
++ goto err_stats;
++
++ if (enabled)
++ ret = start_kthread();
++
++ goto out;
++
++err_stats:
++ ring_buffer_free(ring_buffer);
++out:
++ return ret;
++
++}
++
++/**
++ * detector_exit - Standard module cleanup code
++ */
++static void detector_exit(void)
++{
++ int err;
++
++ if (enabled) {
++ enabled = 0;
++ err = stop_kthread();
++ if (err)
++ pr_err(BANNER "cannot stop kthread\n");
++ }
++
++ free_debugfs();
++ ring_buffer_free(ring_buffer); /* free up the ring buffer */
++
++}
++
++module_init(detector_init);
++module_exit(detector_exit);
+diff -Nur linux-4.8.15.orig/drivers/misc/Kconfig linux-4.8.15/drivers/misc/Kconfig
+--- linux-4.8.15.orig/drivers/misc/Kconfig 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/misc/Kconfig 2017-01-01 17:07:14.579333432 +0100
+@@ -54,6 +54,7 @@
+ config ATMEL_TCLIB
+ bool "Atmel AT32/AT91 Timer/Counter Library"
+ depends on (AVR32 || ARCH_AT91)
++ default y if PREEMPT_RT_FULL
+ help
+ Select this if you want a library to allocate the Timer/Counter
+ blocks found on many Atmel processors. This facilitates using
+@@ -69,8 +70,7 @@
+ are combined to make a single 32-bit timer.
+
+ When GENERIC_CLOCKEVENTS is defined, the third timer channel
+- may be used as a clock event device supporting oneshot mode
+- (delays of up to two seconds) based on the 32 KiHz clock.
++ may be used as a clock event device supporting oneshot mode.
+
+ config ATMEL_TCB_CLKSRC_BLOCK
+ int
+@@ -84,6 +84,15 @@
+ TC can be used for other purposes, such as PWM generation and
+ interval timing.
+
++config ATMEL_TCB_CLKSRC_USE_SLOW_CLOCK
++ bool "TC Block use 32 KiHz clock"
++ depends on ATMEL_TCB_CLKSRC
++ default y if !PREEMPT_RT_FULL
++ help
++ Select this to use 32 KiHz base clock rate as TC block clock
++ source for clock events.
++
++
+ config DUMMY_IRQ
+ tristate "Dummy IRQ handler"
+ default n
+@@ -114,6 +123,35 @@
+ for information on the specific driver level and support statement
+ for your IBM server.
+
++config HWLAT_DETECTOR
++ tristate "Testing module to detect hardware-induced latencies"
++ depends on DEBUG_FS
++ depends on RING_BUFFER
++ default m
++ ---help---
++ A simple hardware latency detector. Use this module to detect
++ large latencies introduced by the behavior of the underlying
++ system firmware external to Linux. We do this using periodic
++ use of stop_machine to grab all available CPUs and measure
++ for unexplainable gaps in the CPU timestamp counter(s). By
++ default, the module is not enabled until the "enable" file
++ within the "hwlat_detector" debugfs directory is toggled.
++
++ This module is often used to detect SMI (System Management
++ Interrupts) on x86 systems, though is not x86 specific. To
++ this end, we default to using a sample window of 1 second,
++ during which we will sample for 0.5 seconds. If an SMI or
++ similar event occurs during that time, it is recorded
++ into an 8K samples global ring buffer until retreived.
++
++ WARNING: This software should never be enabled (it can be built
++ but should not be turned on after it is loaded) in a production
++ environment where high latencies are a concern since the
++ sampling mechanism actually introduces latencies for
++ regular tasks while the CPU(s) are being held.
++
++ If unsure, say N
++
+ config PHANTOM
+ tristate "Sensable PHANToM (PCI)"
+ depends on PCI
+diff -Nur linux-4.8.15.orig/drivers/misc/Makefile linux-4.8.15/drivers/misc/Makefile
+--- linux-4.8.15.orig/drivers/misc/Makefile 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/misc/Makefile 2017-01-01 17:07:14.579333432 +0100
+@@ -38,6 +38,7 @@
+ obj-$(CONFIG_HMC6352) += hmc6352.o
+ obj-y += eeprom/
+ obj-y += cb710/
++obj-$(CONFIG_HWLAT_DETECTOR) += hwlat_detector.o
+ obj-$(CONFIG_SPEAR13XX_PCIE_GADGET) += spear13xx_pcie_gadget.o
+ obj-$(CONFIG_VMWARE_BALLOON) += vmw_balloon.o
+ obj-$(CONFIG_ARM_CHARLCD) += arm-charlcd.o
+diff -Nur linux-4.8.15.orig/drivers/mmc/host/mmci.c linux-4.8.15/drivers/mmc/host/mmci.c
+--- linux-4.8.15.orig/drivers/mmc/host/mmci.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/mmc/host/mmci.c 2017-01-01 17:07:14.591334201 +0100
+@@ -1147,15 +1147,12 @@
+ struct sg_mapping_iter *sg_miter = &host->sg_miter;
+ struct variant_data *variant = host->variant;
+ void __iomem *base = host->base;
+- unsigned long flags;
+ u32 status;
+
+ status = readl(base + MMCISTATUS);
+
+ dev_dbg(mmc_dev(host->mmc), "irq1 (pio) %08x\n", status);
+
+- local_irq_save(flags);
+-
+ do {
+ unsigned int remain, len;
+ char *buffer;
+@@ -1195,8 +1192,6 @@
+
+ sg_miter_stop(sg_miter);
+
+- local_irq_restore(flags);
+-
+ /*
+ * If we have less than the fifo 'half-full' threshold to transfer,
+ * trigger a PIO interrupt as soon as any data is available.
+diff -Nur linux-4.8.15.orig/drivers/net/ethernet/3com/3c59x.c linux-4.8.15/drivers/net/ethernet/3com/3c59x.c
+--- linux-4.8.15.orig/drivers/net/ethernet/3com/3c59x.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/net/ethernet/3com/3c59x.c 2017-01-01 17:07:14.611335500 +0100
+@@ -842,9 +842,9 @@
+ {
+ struct vortex_private *vp = netdev_priv(dev);
+ unsigned long flags;
+- local_irq_save(flags);
++ local_irq_save_nort(flags);
+ (vp->full_bus_master_rx ? boomerang_interrupt:vortex_interrupt)(dev->irq,dev);
+- local_irq_restore(flags);
++ local_irq_restore_nort(flags);
+ }
+ #endif
+
+@@ -1910,12 +1910,12 @@
+ * Block interrupts because vortex_interrupt does a bare spin_lock()
+ */
+ unsigned long flags;
+- local_irq_save(flags);
++ local_irq_save_nort(flags);
+ if (vp->full_bus_master_tx)
+ boomerang_interrupt(dev->irq, dev);
+ else
+ vortex_interrupt(dev->irq, dev);
+- local_irq_restore(flags);
++ local_irq_restore_nort(flags);
+ }
+ }
+
+diff -Nur linux-4.8.15.orig/drivers/net/ethernet/realtek/8139too.c linux-4.8.15/drivers/net/ethernet/realtek/8139too.c
+--- linux-4.8.15.orig/drivers/net/ethernet/realtek/8139too.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/net/ethernet/realtek/8139too.c 2017-01-01 17:07:14.639337303 +0100
+@@ -2233,7 +2233,7 @@
+ struct rtl8139_private *tp = netdev_priv(dev);
+ const int irq = tp->pci_dev->irq;
+
+- disable_irq(irq);
++ disable_irq_nosync(irq);
+ rtl8139_interrupt(irq, dev);
+ enable_irq(irq);
+ }
+diff -Nur linux-4.8.15.orig/drivers/net/wireless/intersil/orinoco/orinoco_usb.c linux-4.8.15/drivers/net/wireless/intersil/orinoco/orinoco_usb.c
+--- linux-4.8.15.orig/drivers/net/wireless/intersil/orinoco/orinoco_usb.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/net/wireless/intersil/orinoco/orinoco_usb.c 2017-01-01 17:07:14.687340389 +0100
+@@ -697,7 +697,7 @@
+ while (!ctx->done.done && msecs--)
+ udelay(1000);
+ } else {
+- wait_event_interruptible(ctx->done.wait,
++ swait_event_interruptible(ctx->done.wait,
+ ctx->done.done);
+ }
+ break;
+diff -Nur linux-4.8.15.orig/drivers/pci/access.c linux-4.8.15/drivers/pci/access.c
+--- linux-4.8.15.orig/drivers/pci/access.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/pci/access.c 2017-01-01 17:07:14.699341161 +0100
+@@ -672,7 +672,7 @@
+ WARN_ON(!dev->block_cfg_access);
+
+ dev->block_cfg_access = 0;
+- wake_up_all(&pci_cfg_wait);
++ wake_up_all_locked(&pci_cfg_wait);
+ raw_spin_unlock_irqrestore(&pci_lock, flags);
+ }
+ EXPORT_SYMBOL_GPL(pci_cfg_access_unlock);
+diff -Nur linux-4.8.15.orig/drivers/scsi/fcoe/fcoe.c linux-4.8.15/drivers/scsi/fcoe/fcoe.c
+--- linux-4.8.15.orig/drivers/scsi/fcoe/fcoe.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/scsi/fcoe/fcoe.c 2017-01-01 17:07:14.719342449 +0100
+@@ -1455,11 +1455,11 @@
+ static int fcoe_alloc_paged_crc_eof(struct sk_buff *skb, int tlen)
+ {
+ struct fcoe_percpu_s *fps;
+- int rc;
++ int rc, cpu = get_cpu_light();
+
+- fps = &get_cpu_var(fcoe_percpu);
++ fps = &per_cpu(fcoe_percpu, cpu);
+ rc = fcoe_get_paged_crc_eof(skb, tlen, fps);
+- put_cpu_var(fcoe_percpu);
++ put_cpu_light();
+
+ return rc;
+ }
+@@ -1646,11 +1646,11 @@
+ return 0;
+ }
+
+- stats = per_cpu_ptr(lport->stats, get_cpu());
++ stats = per_cpu_ptr(lport->stats, get_cpu_light());
+ stats->InvalidCRCCount++;
+ if (stats->InvalidCRCCount < 5)
+ printk(KERN_WARNING "fcoe: dropping frame with CRC error\n");
+- put_cpu();
++ put_cpu_light();
+ return -EINVAL;
+ }
+
+@@ -1693,7 +1693,7 @@
+ */
+ hp = (struct fcoe_hdr *) skb_network_header(skb);
+
+- stats = per_cpu_ptr(lport->stats, get_cpu());
++ stats = per_cpu_ptr(lport->stats, get_cpu_light());
+ if (unlikely(FC_FCOE_DECAPS_VER(hp) != FC_FCOE_VER)) {
+ if (stats->ErrorFrames < 5)
+ printk(KERN_WARNING "fcoe: FCoE version "
+@@ -1725,13 +1725,13 @@
+ goto drop;
+
+ if (!fcoe_filter_frames(lport, fp)) {
+- put_cpu();
++ put_cpu_light();
+ fc_exch_recv(lport, fp);
+ return;
+ }
+ drop:
+ stats->ErrorFrames++;
+- put_cpu();
++ put_cpu_light();
+ kfree_skb(skb);
+ }
+
+diff -Nur linux-4.8.15.orig/drivers/scsi/fcoe/fcoe_ctlr.c linux-4.8.15/drivers/scsi/fcoe/fcoe_ctlr.c
+--- linux-4.8.15.orig/drivers/scsi/fcoe/fcoe_ctlr.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/scsi/fcoe/fcoe_ctlr.c 2017-01-01 17:07:14.727342965 +0100
+@@ -834,7 +834,7 @@
+
+ INIT_LIST_HEAD(&del_list);
+
+- stats = per_cpu_ptr(fip->lp->stats, get_cpu());
++ stats = per_cpu_ptr(fip->lp->stats, get_cpu_light());
+
+ list_for_each_entry_safe(fcf, next, &fip->fcfs, list) {
+ deadline = fcf->time + fcf->fka_period + fcf->fka_period / 2;
+@@ -870,7 +870,7 @@
+ sel_time = fcf->time;
+ }
+ }
+- put_cpu();
++ put_cpu_light();
+
+ list_for_each_entry_safe(fcf, next, &del_list, list) {
+ /* Removes fcf from current list */
+diff -Nur linux-4.8.15.orig/drivers/scsi/libfc/fc_exch.c linux-4.8.15/drivers/scsi/libfc/fc_exch.c
+--- linux-4.8.15.orig/drivers/scsi/libfc/fc_exch.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/scsi/libfc/fc_exch.c 2017-01-01 17:07:14.747344253 +0100
+@@ -814,10 +814,10 @@
+ }
+ memset(ep, 0, sizeof(*ep));
+
+- cpu = get_cpu();
++ cpu = get_cpu_light();
+ pool = per_cpu_ptr(mp->pool, cpu);
+ spin_lock_bh(&pool->lock);
+- put_cpu();
++ put_cpu_light();
+
+ /* peek cache of free slot */
+ if (pool->left != FC_XID_UNKNOWN) {
+diff -Nur linux-4.8.15.orig/drivers/scsi/libsas/sas_ata.c linux-4.8.15/drivers/scsi/libsas/sas_ata.c
+--- linux-4.8.15.orig/drivers/scsi/libsas/sas_ata.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/scsi/libsas/sas_ata.c 2017-01-01 17:07:14.791347085 +0100
+@@ -190,7 +190,7 @@
+ /* TODO: audit callers to ensure they are ready for qc_issue to
+ * unconditionally re-enable interrupts
+ */
+- local_irq_save(flags);
++ local_irq_save_nort(flags);
+ spin_unlock(ap->lock);
+
+ /* If the device fell off, no sense in issuing commands */
+@@ -252,7 +252,7 @@
+
+ out:
+ spin_lock(ap->lock);
+- local_irq_restore(flags);
++ local_irq_restore_nort(flags);
+ return ret;
+ }
+
+diff -Nur linux-4.8.15.orig/drivers/scsi/qla2xxx/qla_inline.h linux-4.8.15/drivers/scsi/qla2xxx/qla_inline.h
+--- linux-4.8.15.orig/drivers/scsi/qla2xxx/qla_inline.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/scsi/qla2xxx/qla_inline.h 2017-01-01 17:07:14.807348125 +0100
+@@ -59,12 +59,12 @@
+ {
+ unsigned long flags;
+ struct qla_hw_data *ha = rsp->hw;
+- local_irq_save(flags);
++ local_irq_save_nort(flags);
+ if (IS_P3P_TYPE(ha))
+ qla82xx_poll(0, rsp);
+ else
+ ha->isp_ops->intr_handler(0, rsp);
+- local_irq_restore(flags);
++ local_irq_restore_nort(flags);
+ }
+
+ static inline uint8_t *
+diff -Nur linux-4.8.15.orig/drivers/scsi/qla2xxx/qla_isr.c linux-4.8.15/drivers/scsi/qla2xxx/qla_isr.c
+--- linux-4.8.15.orig/drivers/scsi/qla2xxx/qla_isr.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/scsi/qla2xxx/qla_isr.c 2017-01-01 17:07:14.831349662 +0100
+@@ -3125,7 +3125,11 @@
+ * kref_put().
+ */
+ kref_get(&qentry->irq_notify.kref);
++#ifdef CONFIG_PREEMPT_RT_BASE
++ swork_queue(&qentry->irq_notify.swork);
++#else
+ schedule_work(&qentry->irq_notify.work);
++#endif
+ }
+
+ /*
+diff -Nur linux-4.8.15.orig/drivers/thermal/x86_pkg_temp_thermal.c linux-4.8.15/drivers/thermal/x86_pkg_temp_thermal.c
+--- linux-4.8.15.orig/drivers/thermal/x86_pkg_temp_thermal.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/thermal/x86_pkg_temp_thermal.c 2017-01-01 17:07:14.843350438 +0100
+@@ -29,6 +29,7 @@
+ #include <linux/pm.h>
+ #include <linux/thermal.h>
+ #include <linux/debugfs.h>
++#include <linux/swork.h>
+ #include <asm/cpu_device_id.h>
+ #include <asm/mce.h>
+
+@@ -352,7 +353,7 @@
+ }
+ }
+
+-static int pkg_temp_thermal_platform_thermal_notify(__u64 msr_val)
++static void platform_thermal_notify_work(struct swork_event *event)
+ {
+ unsigned long flags;
+ int cpu = smp_processor_id();
+@@ -369,7 +370,7 @@
+ pkg_work_scheduled[phy_id]) {
+ disable_pkg_thres_interrupt();
+ spin_unlock_irqrestore(&pkg_work_lock, flags);
+- return -EINVAL;
++ return;
+ }
+ pkg_work_scheduled[phy_id] = 1;
+ spin_unlock_irqrestore(&pkg_work_lock, flags);
+@@ -378,9 +379,48 @@
+ schedule_delayed_work_on(cpu,
+ &per_cpu(pkg_temp_thermal_threshold_work, cpu),
+ msecs_to_jiffies(notify_delay_ms));
++}
++
++#ifdef CONFIG_PREEMPT_RT_FULL
++static struct swork_event notify_work;
++
++static int thermal_notify_work_init(void)
++{
++ int err;
++
++ err = swork_get();
++ if (err)
++ return err;
++
++ INIT_SWORK(&notify_work, platform_thermal_notify_work);
+ return 0;
+ }
+
++static void thermal_notify_work_cleanup(void)
++{
++ swork_put();
++}
++
++static int pkg_temp_thermal_platform_thermal_notify(__u64 msr_val)
++{
++ swork_queue(&notify_work);
++ return 0;
++}
++
++#else /* !CONFIG_PREEMPT_RT_FULL */
++
++static int thermal_notify_work_init(void) { return 0; }
++
++static void thermal_notify_work_cleanup(void) { }
++
++static int pkg_temp_thermal_platform_thermal_notify(__u64 msr_val)
++{
++ platform_thermal_notify_work(NULL);
++
++ return 0;
++}
++#endif /* CONFIG_PREEMPT_RT_FULL */
++
+ static int find_siblings_cpu(int cpu)
+ {
+ int i;
+@@ -584,6 +624,9 @@
+ if (!x86_match_cpu(pkg_temp_thermal_ids))
+ return -ENODEV;
+
++ if (!thermal_notify_work_init())
++ return -ENODEV;
++
+ spin_lock_init(&pkg_work_lock);
+ platform_thermal_package_notify =
+ pkg_temp_thermal_platform_thermal_notify;
+@@ -608,7 +651,7 @@
+ kfree(pkg_work_scheduled);
+ platform_thermal_package_notify = NULL;
+ platform_thermal_package_rate_control = NULL;
+-
++ thermal_notify_work_cleanup();
+ return -ENODEV;
+ }
+
+@@ -633,6 +676,7 @@
+ mutex_unlock(&phy_dev_list_mutex);
+ platform_thermal_package_notify = NULL;
+ platform_thermal_package_rate_control = NULL;
++ thermal_notify_work_cleanup();
+ for_each_online_cpu(i)
+ cancel_delayed_work_sync(
+ &per_cpu(pkg_temp_thermal_threshold_work, i));
+diff -Nur linux-4.8.15.orig/drivers/tty/serial/8250/8250_core.c linux-4.8.15/drivers/tty/serial/8250/8250_core.c
+--- linux-4.8.15.orig/drivers/tty/serial/8250/8250_core.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/tty/serial/8250/8250_core.c 2017-01-01 17:07:14.859351469 +0100
+@@ -58,7 +58,16 @@
+
+ static unsigned int skip_txen_test; /* force skip of txen test at init time */
+
+-#define PASS_LIMIT 512
++/*
++ * On -rt we can have a more delays, and legitimately
++ * so - so don't drop work spuriously and spam the
++ * syslog:
++ */
++#ifdef CONFIG_PREEMPT_RT_FULL
++# define PASS_LIMIT 1000000
++#else
++# define PASS_LIMIT 512
++#endif
+
+ #include <asm/serial.h>
+ /*
+diff -Nur linux-4.8.15.orig/drivers/tty/serial/8250/8250_port.c linux-4.8.15/drivers/tty/serial/8250/8250_port.c
+--- linux-4.8.15.orig/drivers/tty/serial/8250/8250_port.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/tty/serial/8250/8250_port.c 2017-01-01 17:07:14.895353784 +0100
+@@ -35,6 +35,7 @@
+ #include <linux/nmi.h>
+ #include <linux/mutex.h>
+ #include <linux/slab.h>
++#include <linux/kdb.h>
+ #include <linux/uaccess.h>
+ #include <linux/pm_runtime.h>
+ #include <linux/timer.h>
+@@ -3109,9 +3110,9 @@
+
+ serial8250_rpm_get(up);
+
+- if (port->sysrq)
++ if (port->sysrq || oops_in_progress)
+ locked = 0;
+- else if (oops_in_progress)
++ else if (in_kdb_printk())
+ locked = spin_trylock_irqsave(&port->lock, flags);
+ else
+ spin_lock_irqsave(&port->lock, flags);
+diff -Nur linux-4.8.15.orig/drivers/tty/serial/amba-pl011.c linux-4.8.15/drivers/tty/serial/amba-pl011.c
+--- linux-4.8.15.orig/drivers/tty/serial/amba-pl011.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/tty/serial/amba-pl011.c 2017-01-01 17:07:15.011361259 +0100
+@@ -2167,13 +2167,19 @@
+
+ clk_enable(uap->clk);
+
+- local_irq_save(flags);
++ /*
++ * local_irq_save(flags);
++ *
++ * This local_irq_save() is nonsense. If we come in via sysrq
++ * handling then interrupts are already disabled. Aside of
++ * that the port.sysrq check is racy on SMP regardless.
++ */
+ if (uap->port.sysrq)
+ locked = 0;
+ else if (oops_in_progress)
+- locked = spin_trylock(&uap->port.lock);
++ locked = spin_trylock_irqsave(&uap->port.lock, flags);
+ else
+- spin_lock(&uap->port.lock);
++ spin_lock_irqsave(&uap->port.lock, flags);
+
+ /*
+ * First save the CR then disable the interrupts
+@@ -2197,8 +2203,7 @@
+ pl011_write(old_cr, uap, REG_CR);
+
+ if (locked)
+- spin_unlock(&uap->port.lock);
+- local_irq_restore(flags);
++ spin_unlock_irqrestore(&uap->port.lock, flags);
+
+ clk_disable(uap->clk);
+ }
+diff -Nur linux-4.8.15.orig/drivers/tty/serial/omap-serial.c linux-4.8.15/drivers/tty/serial/omap-serial.c
+--- linux-4.8.15.orig/drivers/tty/serial/omap-serial.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/tty/serial/omap-serial.c 2017-01-01 17:07:15.019361774 +0100
+@@ -1257,13 +1257,10 @@
+
+ pm_runtime_get_sync(up->dev);
+
+- local_irq_save(flags);
+- if (up->port.sysrq)
+- locked = 0;
+- else if (oops_in_progress)
+- locked = spin_trylock(&up->port.lock);
++ if (up->port.sysrq || oops_in_progress)
++ locked = spin_trylock_irqsave(&up->port.lock, flags);
+ else
+- spin_lock(&up->port.lock);
++ spin_lock_irqsave(&up->port.lock, flags);
+
+ /*
+ * First save the IER then disable the interrupts
+@@ -1292,8 +1289,7 @@
+ pm_runtime_mark_last_busy(up->dev);
+ pm_runtime_put_autosuspend(up->dev);
+ if (locked)
+- spin_unlock(&up->port.lock);
+- local_irq_restore(flags);
++ spin_unlock_irqrestore(&up->port.lock, flags);
+ }
+
+ static int __init
+diff -Nur linux-4.8.15.orig/drivers/tty/serial/sc16is7xx.c linux-4.8.15/drivers/tty/serial/sc16is7xx.c
+--- linux-4.8.15.orig/drivers/tty/serial/sc16is7xx.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/tty/serial/sc16is7xx.c 2017-01-01 17:07:15.027362288 +0100
+@@ -1240,7 +1240,7 @@
+
+ /* Setup interrupt */
+ ret = devm_request_irq(dev, irq, sc16is7xx_irq,
+- IRQF_ONESHOT | flags, dev_name(dev), s);
++ flags, dev_name(dev), s);
+ if (!ret)
+ return 0;
+
+diff -Nur linux-4.8.15.orig/drivers/usb/core/hcd.c linux-4.8.15/drivers/usb/core/hcd.c
+--- linux-4.8.15.orig/drivers/usb/core/hcd.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/usb/core/hcd.c 2017-01-01 17:07:15.051363831 +0100
+@@ -1760,9 +1760,9 @@
+ * and no one may trigger the above deadlock situation when
+ * running complete() in tasklet.
+ */
+- local_irq_save(flags);
++ local_irq_save_nort(flags);
+ urb->complete(urb);
+- local_irq_restore(flags);
++ local_irq_restore_nort(flags);
+
+ usb_anchor_resume_wakeups(anchor);
+ atomic_dec(&urb->use_count);
+diff -Nur linux-4.8.15.orig/drivers/usb/gadget/function/f_fs.c linux-4.8.15/drivers/usb/gadget/function/f_fs.c
+--- linux-4.8.15.orig/drivers/usb/gadget/function/f_fs.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/usb/gadget/function/f_fs.c 2017-01-01 17:07:15.079365638 +0100
+@@ -1590,7 +1590,7 @@
+ pr_info("%s(): freeing\n", __func__);
+ ffs_data_clear(ffs);
+ BUG_ON(waitqueue_active(&ffs->ev.waitq) ||
+- waitqueue_active(&ffs->ep0req_completion.wait));
++ swait_active(&ffs->ep0req_completion.wait));
+ kfree(ffs->dev_name);
+ kfree(ffs);
+ }
+diff -Nur linux-4.8.15.orig/drivers/usb/gadget/legacy/inode.c linux-4.8.15/drivers/usb/gadget/legacy/inode.c
+--- linux-4.8.15.orig/drivers/usb/gadget/legacy/inode.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/drivers/usb/gadget/legacy/inode.c 2017-01-01 17:07:15.107367440 +0100
+@@ -346,7 +346,7 @@
+ spin_unlock_irq (&epdata->dev->lock);
+
+ if (likely (value == 0)) {
+- value = wait_event_interruptible (done.wait, done.done);
++ value = swait_event_interruptible (done.wait, done.done);
+ if (value != 0) {
+ spin_lock_irq (&epdata->dev->lock);
+ if (likely (epdata->ep != NULL)) {
+@@ -355,7 +355,7 @@
+ usb_ep_dequeue (epdata->ep, epdata->req);
+ spin_unlock_irq (&epdata->dev->lock);
+
+- wait_event (done.wait, done.done);
++ swait_event (done.wait, done.done);
+ if (epdata->status == -ECONNRESET)
+ epdata->status = -EINTR;
+ } else {
+diff -Nur linux-4.8.15.orig/fs/aio.c linux-4.8.15/fs/aio.c
+--- linux-4.8.15.orig/fs/aio.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/fs/aio.c 2017-01-01 17:07:15.119368222 +0100
+@@ -40,6 +40,7 @@
+ #include <linux/ramfs.h>
+ #include <linux/percpu-refcount.h>
+ #include <linux/mount.h>
++#include <linux/swork.h>
+
+ #include <asm/kmap_types.h>
+ #include <asm/uaccess.h>
+@@ -115,7 +116,7 @@
+ struct page **ring_pages;
+ long nr_pages;
+
+- struct work_struct free_work;
++ struct swork_event free_work;
+
+ /*
+ * signals when all in-flight requests are done
+@@ -258,6 +259,7 @@
+ .mount = aio_mount,
+ .kill_sb = kill_anon_super,
+ };
++ BUG_ON(swork_get());
+ aio_mnt = kern_mount(&aio_fs);
+ if (IS_ERR(aio_mnt))
+ panic("Failed to create aio fs mount.");
+@@ -578,9 +580,9 @@
+ return cancel(&kiocb->common);
+ }
+
+-static void free_ioctx(struct work_struct *work)
++static void free_ioctx(struct swork_event *sev)
+ {
+- struct kioctx *ctx = container_of(work, struct kioctx, free_work);
++ struct kioctx *ctx = container_of(sev, struct kioctx, free_work);
+
+ pr_debug("freeing %p\n", ctx);
+
+@@ -599,8 +601,8 @@
+ if (ctx->rq_wait && atomic_dec_and_test(&ctx->rq_wait->count))
+ complete(&ctx->rq_wait->comp);
+
+- INIT_WORK(&ctx->free_work, free_ioctx);
+- schedule_work(&ctx->free_work);
++ INIT_SWORK(&ctx->free_work, free_ioctx);
++ swork_queue(&ctx->free_work);
+ }
+
+ /*
+@@ -608,9 +610,9 @@
+ * and ctx->users has dropped to 0, so we know no more kiocbs can be submitted -
+ * now it's safe to cancel any that need to be.
+ */
+-static void free_ioctx_users(struct percpu_ref *ref)
++static void free_ioctx_users_work(struct swork_event *sev)
+ {
+- struct kioctx *ctx = container_of(ref, struct kioctx, users);
++ struct kioctx *ctx = container_of(sev, struct kioctx, free_work);
+ struct aio_kiocb *req;
+
+ spin_lock_irq(&ctx->ctx_lock);
+@@ -629,6 +631,14 @@
+ percpu_ref_put(&ctx->reqs);
+ }
+
++static void free_ioctx_users(struct percpu_ref *ref)
++{
++ struct kioctx *ctx = container_of(ref, struct kioctx, users);
++
++ INIT_SWORK(&ctx->free_work, free_ioctx_users_work);
++ swork_queue(&ctx->free_work);
++}
++
+ static int ioctx_add_table(struct kioctx *ctx, struct mm_struct *mm)
+ {
+ unsigned i, new_nr;
+diff -Nur linux-4.8.15.orig/fs/autofs4/autofs_i.h linux-4.8.15/fs/autofs4/autofs_i.h
+--- linux-4.8.15.orig/fs/autofs4/autofs_i.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/fs/autofs4/autofs_i.h 2017-01-01 17:07:15.127368729 +0100
+@@ -30,6 +30,7 @@
+ #include <linux/sched.h>
+ #include <linux/mount.h>
+ #include <linux/namei.h>
++#include <linux/delay.h>
+ #include <asm/current.h>
+ #include <linux/uaccess.h>
+
+diff -Nur linux-4.8.15.orig/fs/autofs4/expire.c linux-4.8.15/fs/autofs4/expire.c
+--- linux-4.8.15.orig/fs/autofs4/expire.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/fs/autofs4/expire.c 2017-01-01 17:07:15.143369757 +0100
+@@ -148,7 +148,7 @@
+ parent = p->d_parent;
+ if (!spin_trylock(&parent->d_lock)) {
+ spin_unlock(&p->d_lock);
+- cpu_relax();
++ cpu_chill();
+ goto relock;
+ }
+ spin_unlock(&p->d_lock);
+diff -Nur linux-4.8.15.orig/fs/buffer.c linux-4.8.15/fs/buffer.c
+--- linux-4.8.15.orig/fs/buffer.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/fs/buffer.c 2017-01-01 17:07:15.163371048 +0100
+@@ -301,8 +301,7 @@
+ * decide that the page is now completely done.
+ */
+ first = page_buffers(page);
+- local_irq_save(flags);
+- bit_spin_lock(BH_Uptodate_Lock, &first->b_state);
++ flags = bh_uptodate_lock_irqsave(first);
+ clear_buffer_async_read(bh);
+ unlock_buffer(bh);
+ tmp = bh;
+@@ -315,8 +314,7 @@
+ }
+ tmp = tmp->b_this_page;
+ } while (tmp != bh);
+- bit_spin_unlock(BH_Uptodate_Lock, &first->b_state);
+- local_irq_restore(flags);
++ bh_uptodate_unlock_irqrestore(first, flags);
+
+ /*
+ * If none of the buffers had errors and they are all
+@@ -328,9 +326,7 @@
+ return;
+
+ still_busy:
+- bit_spin_unlock(BH_Uptodate_Lock, &first->b_state);
+- local_irq_restore(flags);
+- return;
++ bh_uptodate_unlock_irqrestore(first, flags);
+ }
+
+ /*
+@@ -358,8 +354,7 @@
+ }
+
+ first = page_buffers(page);
+- local_irq_save(flags);
+- bit_spin_lock(BH_Uptodate_Lock, &first->b_state);
++ flags = bh_uptodate_lock_irqsave(first);
+
+ clear_buffer_async_write(bh);
+ unlock_buffer(bh);
+@@ -371,15 +366,12 @@
+ }
+ tmp = tmp->b_this_page;
+ }
+- bit_spin_unlock(BH_Uptodate_Lock, &first->b_state);
+- local_irq_restore(flags);
++ bh_uptodate_unlock_irqrestore(first, flags);
+ end_page_writeback(page);
+ return;
+
+ still_busy:
+- bit_spin_unlock(BH_Uptodate_Lock, &first->b_state);
+- local_irq_restore(flags);
+- return;
++ bh_uptodate_unlock_irqrestore(first, flags);
+ }
+ EXPORT_SYMBOL(end_buffer_async_write);
+
+@@ -3384,6 +3376,7 @@
+ struct buffer_head *ret = kmem_cache_zalloc(bh_cachep, gfp_flags);
+ if (ret) {
+ INIT_LIST_HEAD(&ret->b_assoc_buffers);
++ buffer_head_init_locks(ret);
+ preempt_disable();
+ __this_cpu_inc(bh_accounting.nr);
+ recalc_bh_state();
+diff -Nur linux-4.8.15.orig/fs/cifs/readdir.c linux-4.8.15/fs/cifs/readdir.c
+--- linux-4.8.15.orig/fs/cifs/readdir.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/fs/cifs/readdir.c 2017-01-01 17:07:15.175371817 +0100
+@@ -80,7 +80,7 @@
+ struct inode *inode;
+ struct super_block *sb = parent->d_sb;
+ struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
+- DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
++ DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq);
+
+ cifs_dbg(FYI, "%s: for %s\n", __func__, name->name);
+
+diff -Nur linux-4.8.15.orig/fs/dcache.c linux-4.8.15/fs/dcache.c
+--- linux-4.8.15.orig/fs/dcache.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/fs/dcache.c 2017-01-01 17:07:15.191372851 +0100
+@@ -19,6 +19,7 @@
+ #include <linux/mm.h>
+ #include <linux/fs.h>
+ #include <linux/fsnotify.h>
++#include <linux/delay.h>
+ #include <linux/slab.h>
+ #include <linux/init.h>
+ #include <linux/hash.h>
+@@ -750,6 +751,8 @@
+ */
+ void dput(struct dentry *dentry)
+ {
++ struct dentry *parent;
++
+ if (unlikely(!dentry))
+ return;
+
+@@ -788,9 +791,18 @@
+ return;
+
+ kill_it:
+- dentry = dentry_kill(dentry);
+- if (dentry) {
+- cond_resched();
++ parent = dentry_kill(dentry);
++ if (parent) {
++ int r;
++
++ if (parent == dentry) {
++ /* the task with the highest priority won't schedule */
++ r = cond_resched();
++ if (!r)
++ cpu_chill();
++ } else {
++ dentry = parent;
++ }
+ goto repeat;
+ }
+ }
+@@ -2321,7 +2333,7 @@
+ if (dentry->d_lockref.count == 1) {
+ if (!spin_trylock(&inode->i_lock)) {
+ spin_unlock(&dentry->d_lock);
+- cpu_relax();
++ cpu_chill();
+ goto again;
+ }
+ dentry->d_flags &= ~DCACHE_CANT_MOUNT;
+@@ -2381,21 +2393,24 @@
+
+ static void d_wait_lookup(struct dentry *dentry)
+ {
+- if (d_in_lookup(dentry)) {
+- DECLARE_WAITQUEUE(wait, current);
+- add_wait_queue(dentry->d_wait, &wait);
+- do {
+- set_current_state(TASK_UNINTERRUPTIBLE);
+- spin_unlock(&dentry->d_lock);
+- schedule();
+- spin_lock(&dentry->d_lock);
+- } while (d_in_lookup(dentry));
+- }
++ struct swait_queue __wait;
++
++ if (!d_in_lookup(dentry))
++ return;
++
++ INIT_LIST_HEAD(&__wait.task_list);
++ do {
++ prepare_to_swait(dentry->d_wait, &__wait, TASK_UNINTERRUPTIBLE);
++ spin_unlock(&dentry->d_lock);
++ schedule();
++ spin_lock(&dentry->d_lock);
++ } while (d_in_lookup(dentry));
++ finish_swait(dentry->d_wait, &__wait);
+ }
+
+ struct dentry *d_alloc_parallel(struct dentry *parent,
+ const struct qstr *name,
+- wait_queue_head_t *wq)
++ struct swait_queue_head *wq)
+ {
+ unsigned int hash = name->hash;
+ struct hlist_bl_head *b = in_lookup_hash(parent, hash);
+@@ -2504,7 +2519,7 @@
+ hlist_bl_lock(b);
+ dentry->d_flags &= ~DCACHE_PAR_LOOKUP;
+ __hlist_bl_del(&dentry->d_u.d_in_lookup_hash);
+- wake_up_all(dentry->d_wait);
++ swake_up_all(dentry->d_wait);
+ dentry->d_wait = NULL;
+ hlist_bl_unlock(b);
+ INIT_HLIST_NODE(&dentry->d_u.d_alias);
+@@ -3601,6 +3616,11 @@
+
+ void __init vfs_caches_init_early(void)
+ {
++ int i;
++
++ for (i = 0; i < ARRAY_SIZE(in_lookup_hashtable); i++)
++ INIT_HLIST_BL_HEAD(&in_lookup_hashtable[i]);
++
+ dcache_init_early();
+ inode_init_early();
+ }
+diff -Nur linux-4.8.15.orig/fs/eventpoll.c linux-4.8.15/fs/eventpoll.c
+--- linux-4.8.15.orig/fs/eventpoll.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/fs/eventpoll.c 2017-01-01 17:07:15.235375683 +0100
+@@ -510,12 +510,12 @@
+ */
+ static void ep_poll_safewake(wait_queue_head_t *wq)
+ {
+- int this_cpu = get_cpu();
++ int this_cpu = get_cpu_light();
+
+ ep_call_nested(&poll_safewake_ncalls, EP_MAX_NESTS,
+ ep_poll_wakeup_proc, NULL, wq, (void *) (long) this_cpu);
+
+- put_cpu();
++ put_cpu_light();
+ }
+
+ static void ep_remove_wait_queue(struct eppoll_entry *pwq)
+diff -Nur linux-4.8.15.orig/fs/exec.c linux-4.8.15/fs/exec.c
+--- linux-4.8.15.orig/fs/exec.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/fs/exec.c 2017-01-01 17:07:15.275378262 +0100
+@@ -1012,12 +1012,14 @@
+ }
+ }
+ task_lock(tsk);
++ preempt_disable_rt();
+ active_mm = tsk->active_mm;
+ tsk->mm = mm;
+ tsk->active_mm = mm;
+ activate_mm(active_mm, mm);
+ tsk->mm->vmacache_seqnum = 0;
+ vmacache_flush(tsk);
++ preempt_enable_rt();
+ task_unlock(tsk);
+ if (old_mm) {
+ up_read(&old_mm->mmap_sem);
+diff -Nur linux-4.8.15.orig/fs/fuse/dir.c linux-4.8.15/fs/fuse/dir.c
+--- linux-4.8.15.orig/fs/fuse/dir.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/fs/fuse/dir.c 2017-01-01 17:07:15.315380835 +0100
+@@ -1174,7 +1174,7 @@
+ struct inode *dir = d_inode(parent);
+ struct fuse_conn *fc;
+ struct inode *inode;
+- DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
++ DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq);
+
+ if (!o->nodeid) {
+ /*
+diff -Nur linux-4.8.15.orig/fs/jbd2/checkpoint.c linux-4.8.15/fs/jbd2/checkpoint.c
+--- linux-4.8.15.orig/fs/jbd2/checkpoint.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/fs/jbd2/checkpoint.c 2017-01-01 17:07:15.403386504 +0100
+@@ -116,6 +116,8 @@
+ nblocks = jbd2_space_needed(journal);
+ while (jbd2_log_space_left(journal) < nblocks) {
+ write_unlock(&journal->j_state_lock);
++ if (current->plug)
++ io_schedule();
+ mutex_lock(&journal->j_checkpoint_mutex);
+
+ /*
+diff -Nur linux-4.8.15.orig/fs/namei.c linux-4.8.15/fs/namei.c
+--- linux-4.8.15.orig/fs/namei.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/fs/namei.c 2017-01-01 17:07:15.435388569 +0100
+@@ -1629,7 +1629,7 @@
+ {
+ struct dentry *dentry = ERR_PTR(-ENOENT), *old;
+ struct inode *inode = dir->d_inode;
+- DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
++ DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq);
+
+ inode_lock_shared(inode);
+ /* Don't go there if it's already dead */
+@@ -3086,7 +3086,7 @@
+ struct dentry *dentry;
+ int error, create_error = 0;
+ umode_t mode = op->mode;
+- DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
++ DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq);
+
+ if (unlikely(IS_DEADDIR(dir_inode)))
+ return -ENOENT;
+diff -Nur linux-4.8.15.orig/fs/namespace.c linux-4.8.15/fs/namespace.c
+--- linux-4.8.15.orig/fs/namespace.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/fs/namespace.c 2017-01-01 17:07:15.447389339 +0100
+@@ -14,6 +14,7 @@
+ #include <linux/mnt_namespace.h>
+ #include <linux/user_namespace.h>
+ #include <linux/namei.h>
++#include <linux/delay.h>
+ #include <linux/security.h>
+ #include <linux/idr.h>
+ #include <linux/init.h> /* init_rootfs */
+@@ -353,8 +354,11 @@
+ * incremented count after it has set MNT_WRITE_HOLD.
+ */
+ smp_mb();
+- while (ACCESS_ONCE(mnt->mnt.mnt_flags) & MNT_WRITE_HOLD)
+- cpu_relax();
++ while (ACCESS_ONCE(mnt->mnt.mnt_flags) & MNT_WRITE_HOLD) {
++ preempt_enable();
++ cpu_chill();
++ preempt_disable();
++ }
+ /*
+ * After the slowpath clears MNT_WRITE_HOLD, mnt_is_readonly will
+ * be set to match its requirements. So we must not load that until
+diff -Nur linux-4.8.15.orig/fs/nfs/delegation.c linux-4.8.15/fs/nfs/delegation.c
+--- linux-4.8.15.orig/fs/nfs/delegation.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/fs/nfs/delegation.c 2017-01-01 17:07:15.451389604 +0100
+@@ -150,11 +150,11 @@
+ sp = state->owner;
+ /* Block nfs4_proc_unlck */
+ mutex_lock(&sp->so_delegreturn_mutex);
+- seq = raw_seqcount_begin(&sp->so_reclaim_seqcount);
++ seq = read_seqbegin(&sp->so_reclaim_seqlock);
+ err = nfs4_open_delegation_recall(ctx, state, stateid, type);
+ if (!err)
+ err = nfs_delegation_claim_locks(ctx, state, stateid);
+- if (!err && read_seqcount_retry(&sp->so_reclaim_seqcount, seq))
++ if (!err && read_seqretry(&sp->so_reclaim_seqlock, seq))
+ err = -EAGAIN;
+ mutex_unlock(&sp->so_delegreturn_mutex);
+ put_nfs_open_context(ctx);
+diff -Nur linux-4.8.15.orig/fs/nfs/dir.c linux-4.8.15/fs/nfs/dir.c
+--- linux-4.8.15.orig/fs/nfs/dir.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/fs/nfs/dir.c 2017-01-01 17:07:15.455389855 +0100
+@@ -485,7 +485,7 @@
+ void nfs_prime_dcache(struct dentry *parent, struct nfs_entry *entry)
+ {
+ struct qstr filename = QSTR_INIT(entry->name, entry->len);
+- DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
++ DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq);
+ struct dentry *dentry;
+ struct dentry *alias;
+ struct inode *dir = d_inode(parent);
+@@ -1490,7 +1490,7 @@
+ struct file *file, unsigned open_flags,
+ umode_t mode, int *opened)
+ {
+- DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
++ DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq);
+ struct nfs_open_context *ctx;
+ struct dentry *res;
+ struct iattr attr = { .ia_valid = ATTR_OPEN };
+@@ -1805,7 +1805,11 @@
+
+ trace_nfs_rmdir_enter(dir, dentry);
+ if (d_really_is_positive(dentry)) {
++#ifdef CONFIG_PREEMPT_RT_BASE
++ down(&NFS_I(d_inode(dentry))->rmdir_sem);
++#else
+ down_write(&NFS_I(d_inode(dentry))->rmdir_sem);
++#endif
+ error = NFS_PROTO(dir)->rmdir(dir, &dentry->d_name);
+ /* Ensure the VFS deletes this inode */
+ switch (error) {
+@@ -1815,7 +1819,11 @@
+ case -ENOENT:
+ nfs_dentry_handle_enoent(dentry);
+ }
++#ifdef CONFIG_PREEMPT_RT_BASE
++ up(&NFS_I(d_inode(dentry))->rmdir_sem);
++#else
+ up_write(&NFS_I(d_inode(dentry))->rmdir_sem);
++#endif
+ } else
+ error = NFS_PROTO(dir)->rmdir(dir, &dentry->d_name);
+ trace_nfs_rmdir_exit(dir, dentry, error);
+diff -Nur linux-4.8.15.orig/fs/nfs/inode.c linux-4.8.15/fs/nfs/inode.c
+--- linux-4.8.15.orig/fs/nfs/inode.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/fs/nfs/inode.c 2017-01-01 17:07:15.463390369 +0100
+@@ -1957,7 +1957,11 @@
+ nfsi->nrequests = 0;
+ nfsi->commit_info.ncommit = 0;
+ atomic_set(&nfsi->commit_info.rpcs_out, 0);
++#ifdef CONFIG_PREEMPT_RT_BASE
++ sema_init(&nfsi->rmdir_sem, 1);
++#else
+ init_rwsem(&nfsi->rmdir_sem);
++#endif
+ nfs4_init_once(nfsi);
+ }
+
+diff -Nur linux-4.8.15.orig/fs/nfs/nfs4_fs.h linux-4.8.15/fs/nfs/nfs4_fs.h
+--- linux-4.8.15.orig/fs/nfs/nfs4_fs.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/fs/nfs/nfs4_fs.h 2017-01-01 17:07:15.467390636 +0100
+@@ -107,7 +107,7 @@
+ unsigned long so_flags;
+ struct list_head so_states;
+ struct nfs_seqid_counter so_seqid;
+- seqcount_t so_reclaim_seqcount;
++ seqlock_t so_reclaim_seqlock;
+ struct mutex so_delegreturn_mutex;
+ };
+
+diff -Nur linux-4.8.15.orig/fs/nfs/nfs4proc.c linux-4.8.15/fs/nfs/nfs4proc.c
+--- linux-4.8.15.orig/fs/nfs/nfs4proc.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/fs/nfs/nfs4proc.c 2017-01-01 17:07:15.491392171 +0100
+@@ -2525,7 +2525,7 @@
+ unsigned int seq;
+ int ret;
+
+- seq = raw_seqcount_begin(&sp->so_reclaim_seqcount);
++ seq = raw_seqcount_begin(&sp->so_reclaim_seqlock.seqcount);
+
+ ret = _nfs4_proc_open(opendata);
+ if (ret != 0)
+@@ -2561,7 +2561,7 @@
+ ctx->state = state;
+ if (d_inode(dentry) == state->inode) {
+ nfs_inode_attach_open_context(ctx);
+- if (read_seqcount_retry(&sp->so_reclaim_seqcount, seq))
++ if (read_seqretry(&sp->so_reclaim_seqlock, seq))
+ nfs4_schedule_stateid_recovery(server, state);
+ }
+ out:
+diff -Nur linux-4.8.15.orig/fs/nfs/nfs4state.c linux-4.8.15/fs/nfs/nfs4state.c
+--- linux-4.8.15.orig/fs/nfs/nfs4state.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/fs/nfs/nfs4state.c 2017-01-01 17:07:15.527394493 +0100
+@@ -488,7 +488,7 @@
+ nfs4_init_seqid_counter(&sp->so_seqid);
+ atomic_set(&sp->so_count, 1);
+ INIT_LIST_HEAD(&sp->so_lru);
+- seqcount_init(&sp->so_reclaim_seqcount);
++ seqlock_init(&sp->so_reclaim_seqlock);
+ mutex_init(&sp->so_delegreturn_mutex);
+ return sp;
+ }
+@@ -1459,8 +1459,12 @@
+ * recovering after a network partition or a reboot from a
+ * server that doesn't support a grace period.
+ */
++#ifdef CONFIG_PREEMPT_RT_FULL
++ write_seqlock(&sp->so_reclaim_seqlock);
++#else
++ write_seqcount_begin(&sp->so_reclaim_seqlock.seqcount);
++#endif
+ spin_lock(&sp->so_lock);
+- raw_write_seqcount_begin(&sp->so_reclaim_seqcount);
+ restart:
+ list_for_each_entry(state, &sp->so_states, open_states) {
+ if (!test_and_clear_bit(ops->state_flag_bit, &state->flags))
+@@ -1528,14 +1532,20 @@
+ spin_lock(&sp->so_lock);
+ goto restart;
+ }
+- raw_write_seqcount_end(&sp->so_reclaim_seqcount);
+ spin_unlock(&sp->so_lock);
++#ifdef CONFIG_PREEMPT_RT_FULL
++ write_sequnlock(&sp->so_reclaim_seqlock);
++#else
++ write_seqcount_end(&sp->so_reclaim_seqlock.seqcount);
++#endif
+ return 0;
+ out_err:
+ nfs4_put_open_state(state);
+- spin_lock(&sp->so_lock);
+- raw_write_seqcount_end(&sp->so_reclaim_seqcount);
+- spin_unlock(&sp->so_lock);
++#ifdef CONFIG_PREEMPT_RT_FULL
++ write_sequnlock(&sp->so_reclaim_seqlock);
++#else
++ write_seqcount_end(&sp->so_reclaim_seqlock.seqcount);
++#endif
+ return status;
+ }
+
+diff -Nur linux-4.8.15.orig/fs/nfs/unlink.c linux-4.8.15/fs/nfs/unlink.c
+--- linux-4.8.15.orig/fs/nfs/unlink.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/fs/nfs/unlink.c 2017-01-01 17:07:15.531394748 +0100
+@@ -12,7 +12,7 @@
+ #include <linux/sunrpc/clnt.h>
+ #include <linux/nfs_fs.h>
+ #include <linux/sched.h>
+-#include <linux/wait.h>
++#include <linux/swait.h>
+ #include <linux/namei.h>
+ #include <linux/fsnotify.h>
+
+@@ -51,6 +51,29 @@
+ rpc_restart_call_prepare(task);
+ }
+
++#ifdef CONFIG_PREEMPT_RT_BASE
++static void nfs_down_anon(struct semaphore *sema)
++{
++ down(sema);
++}
++
++static void nfs_up_anon(struct semaphore *sema)
++{
++ up(sema);
++}
++
++#else
++static void nfs_down_anon(struct rw_semaphore *rwsem)
++{
++ down_read_non_owner(rwsem);
++}
++
++static void nfs_up_anon(struct rw_semaphore *rwsem)
++{
++ up_read_non_owner(rwsem);
++}
++#endif
++
+ /**
+ * nfs_async_unlink_release - Release the sillydelete data.
+ * @task: rpc_task of the sillydelete
+@@ -64,7 +87,7 @@
+ struct dentry *dentry = data->dentry;
+ struct super_block *sb = dentry->d_sb;
+
+- up_read_non_owner(&NFS_I(d_inode(dentry->d_parent))->rmdir_sem);
++ nfs_up_anon(&NFS_I(d_inode(dentry->d_parent))->rmdir_sem);
+ d_lookup_done(dentry);
+ nfs_free_unlinkdata(data);
+ dput(dentry);
+@@ -117,10 +140,10 @@
+ struct inode *dir = d_inode(dentry->d_parent);
+ struct dentry *alias;
+
+- down_read_non_owner(&NFS_I(dir)->rmdir_sem);
++ nfs_down_anon(&NFS_I(dir)->rmdir_sem);
+ alias = d_alloc_parallel(dentry->d_parent, &data->args.name, &data->wq);
+ if (IS_ERR(alias)) {
+- up_read_non_owner(&NFS_I(dir)->rmdir_sem);
++ nfs_up_anon(&NFS_I(dir)->rmdir_sem);
+ return 0;
+ }
+ if (!d_in_lookup(alias)) {
+@@ -142,7 +165,7 @@
+ ret = 0;
+ spin_unlock(&alias->d_lock);
+ dput(alias);
+- up_read_non_owner(&NFS_I(dir)->rmdir_sem);
++ nfs_up_anon(&NFS_I(dir)->rmdir_sem);
+ /*
+ * If we'd displaced old cached devname, free it. At that
+ * point dentry is definitely not a root, so we won't need
+@@ -182,7 +205,7 @@
+ goto out_free_name;
+ }
+ data->res.dir_attr = &data->dir_attr;
+- init_waitqueue_head(&data->wq);
++ init_swait_queue_head(&data->wq);
+
+ status = -EBUSY;
+ spin_lock(&dentry->d_lock);
+diff -Nur linux-4.8.15.orig/fs/ntfs/aops.c linux-4.8.15/fs/ntfs/aops.c
+--- linux-4.8.15.orig/fs/ntfs/aops.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/fs/ntfs/aops.c 2017-01-01 17:07:15.547395781 +0100
+@@ -92,13 +92,13 @@
+ ofs = 0;
+ if (file_ofs < init_size)
+ ofs = init_size - file_ofs;
+- local_irq_save(flags);
++ local_irq_save_nort(flags);
+ kaddr = kmap_atomic(page);
+ memset(kaddr + bh_offset(bh) + ofs, 0,
+ bh->b_size - ofs);
+ flush_dcache_page(page);
+ kunmap_atomic(kaddr);
+- local_irq_restore(flags);
++ local_irq_restore_nort(flags);
+ }
+ } else {
+ clear_buffer_uptodate(bh);
+@@ -107,8 +107,7 @@
+ "0x%llx.", (unsigned long long)bh->b_blocknr);
+ }
+ first = page_buffers(page);
+- local_irq_save(flags);
+- bit_spin_lock(BH_Uptodate_Lock, &first->b_state);
++ flags = bh_uptodate_lock_irqsave(first);
+ clear_buffer_async_read(bh);
+ unlock_buffer(bh);
+ tmp = bh;
+@@ -123,8 +122,7 @@
+ }
+ tmp = tmp->b_this_page;
+ } while (tmp != bh);
+- bit_spin_unlock(BH_Uptodate_Lock, &first->b_state);
+- local_irq_restore(flags);
++ bh_uptodate_unlock_irqrestore(first, flags);
+ /*
+ * If none of the buffers had errors then we can set the page uptodate,
+ * but we first have to perform the post read mst fixups, if the
+@@ -145,13 +143,13 @@
+ recs = PAGE_SIZE / rec_size;
+ /* Should have been verified before we got here... */
+ BUG_ON(!recs);
+- local_irq_save(flags);
++ local_irq_save_nort(flags);
+ kaddr = kmap_atomic(page);
+ for (i = 0; i < recs; i++)
+ post_read_mst_fixup((NTFS_RECORD*)(kaddr +
+ i * rec_size), rec_size);
+ kunmap_atomic(kaddr);
+- local_irq_restore(flags);
++ local_irq_restore_nort(flags);
+ flush_dcache_page(page);
+ if (likely(page_uptodate && !PageError(page)))
+ SetPageUptodate(page);
+@@ -159,9 +157,7 @@
+ unlock_page(page);
+ return;
+ still_busy:
+- bit_spin_unlock(BH_Uptodate_Lock, &first->b_state);
+- local_irq_restore(flags);
+- return;
++ bh_uptodate_unlock_irqrestore(first, flags);
+ }
+
+ /**
+diff -Nur linux-4.8.15.orig/fs/proc/base.c linux-4.8.15/fs/proc/base.c
+--- linux-4.8.15.orig/fs/proc/base.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/fs/proc/base.c 2017-01-01 17:07:15.571397336 +0100
+@@ -1819,7 +1819,7 @@
+
+ child = d_hash_and_lookup(dir, &qname);
+ if (!child) {
+- DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
++ DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq);
+ child = d_alloc_parallel(dir, &qname, &wq);
+ if (IS_ERR(child))
+ goto end_instantiate;
+diff -Nur linux-4.8.15.orig/fs/proc/proc_sysctl.c linux-4.8.15/fs/proc/proc_sysctl.c
+--- linux-4.8.15.orig/fs/proc/proc_sysctl.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/fs/proc/proc_sysctl.c 2017-01-01 17:07:15.575397587 +0100
+@@ -627,7 +627,7 @@
+
+ child = d_lookup(dir, &qname);
+ if (!child) {
+- DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
++ DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq);
+ child = d_alloc_parallel(dir, &qname, &wq);
+ if (IS_ERR(child))
+ return false;
+diff -Nur linux-4.8.15.orig/fs/timerfd.c linux-4.8.15/fs/timerfd.c
+--- linux-4.8.15.orig/fs/timerfd.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/fs/timerfd.c 2017-01-01 17:07:15.587398365 +0100
+@@ -460,7 +460,10 @@
+ break;
+ }
+ spin_unlock_irq(&ctx->wqh.lock);
+- cpu_relax();
++ if (isalarm(ctx))
++ hrtimer_wait_for_timer(&ctx->t.alarm.timer);
++ else
++ hrtimer_wait_for_timer(&ctx->t.tmr);
+ }
+
+ /*
+diff -Nur linux-4.8.15.orig/include/acpi/platform/aclinux.h linux-4.8.15/include/acpi/platform/aclinux.h
+--- linux-4.8.15.orig/include/acpi/platform/aclinux.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/acpi/platform/aclinux.h 2017-01-01 17:07:15.591398616 +0100
+@@ -131,6 +131,7 @@
+
+ #define acpi_cache_t struct kmem_cache
+ #define acpi_spinlock spinlock_t *
++#define acpi_raw_spinlock raw_spinlock_t *
+ #define acpi_cpu_flags unsigned long
+
+ /* Use native linux version of acpi_os_allocate_zeroed */
+@@ -149,6 +150,20 @@
+ #define ACPI_USE_ALTERNATE_PROTOTYPE_acpi_os_get_thread_id
+ #define ACPI_USE_ALTERNATE_PROTOTYPE_acpi_os_create_lock
+
++#define acpi_os_create_raw_lock(__handle) \
++({ \
++ raw_spinlock_t *lock = ACPI_ALLOCATE(sizeof(*lock)); \
++ \
++ if (lock) { \
++ *(__handle) = lock; \
++ raw_spin_lock_init(*(__handle)); \
++ } \
++ lock ? AE_OK : AE_NO_MEMORY; \
++ })
++
++#define acpi_os_delete_raw_lock(__handle) kfree(__handle)
++
++
+ /*
+ * OSL interfaces used by debugger/disassembler
+ */
+diff -Nur linux-4.8.15.orig/include/asm-generic/bug.h linux-4.8.15/include/asm-generic/bug.h
+--- linux-4.8.15.orig/include/asm-generic/bug.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/asm-generic/bug.h 2017-01-01 17:07:15.591398616 +0100
+@@ -215,6 +215,20 @@
+ # define WARN_ON_SMP(x) ({0;})
+ #endif
+
++#ifdef CONFIG_PREEMPT_RT_BASE
++# define BUG_ON_RT(c) BUG_ON(c)
++# define BUG_ON_NONRT(c) do { } while (0)
++# define WARN_ON_RT(condition) WARN_ON(condition)
++# define WARN_ON_NONRT(condition) do { } while (0)
++# define WARN_ON_ONCE_NONRT(condition) do { } while (0)
++#else
++# define BUG_ON_RT(c) do { } while (0)
++# define BUG_ON_NONRT(c) BUG_ON(c)
++# define WARN_ON_RT(condition) do { } while (0)
++# define WARN_ON_NONRT(condition) WARN_ON(condition)
++# define WARN_ON_ONCE_NONRT(condition) WARN_ON_ONCE(condition)
++#endif
++
+ #endif /* __ASSEMBLY__ */
+
+ #endif
+diff -Nur linux-4.8.15.orig/include/linux/blkdev.h linux-4.8.15/include/linux/blkdev.h
+--- linux-4.8.15.orig/include/linux/blkdev.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/blkdev.h 2017-01-01 17:07:15.623400677 +0100
+@@ -89,6 +89,7 @@
+ struct list_head queuelist;
+ union {
+ struct call_single_data csd;
++ struct work_struct work;
+ u64 fifo_time;
+ };
+
+@@ -467,7 +468,7 @@
+ struct throtl_data *td;
+ #endif
+ struct rcu_head rcu_head;
+- wait_queue_head_t mq_freeze_wq;
++ struct swait_queue_head mq_freeze_wq;
+ struct percpu_ref q_usage_counter;
+ struct list_head all_q_node;
+
+diff -Nur linux-4.8.15.orig/include/linux/blk-mq.h linux-4.8.15/include/linux/blk-mq.h
+--- linux-4.8.15.orig/include/linux/blk-mq.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/blk-mq.h 2017-01-01 17:07:15.599399127 +0100
+@@ -222,6 +222,7 @@
+
+ struct blk_mq_hw_ctx *blk_mq_map_queue(struct request_queue *, const int ctx_index);
+ struct blk_mq_hw_ctx *blk_mq_alloc_single_hw_queue(struct blk_mq_tag_set *, unsigned int, int);
++void __blk_mq_complete_request_remote_work(struct work_struct *work);
+
+ int blk_mq_request_started(struct request *rq);
+ void blk_mq_start_request(struct request *rq);
+diff -Nur linux-4.8.15.orig/include/linux/bottom_half.h linux-4.8.15/include/linux/bottom_half.h
+--- linux-4.8.15.orig/include/linux/bottom_half.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/bottom_half.h 2017-01-01 17:07:15.623400677 +0100
+@@ -3,6 +3,39 @@
+
+ #include <linux/preempt.h>
+
++#ifdef CONFIG_PREEMPT_RT_FULL
++
++extern void __local_bh_disable(void);
++extern void _local_bh_enable(void);
++extern void __local_bh_enable(void);
++
++static inline void local_bh_disable(void)
++{
++ __local_bh_disable();
++}
++
++static inline void __local_bh_disable_ip(unsigned long ip, unsigned int cnt)
++{
++ __local_bh_disable();
++}
++
++static inline void local_bh_enable(void)
++{
++ __local_bh_enable();
++}
++
++static inline void __local_bh_enable_ip(unsigned long ip, unsigned int cnt)
++{
++ __local_bh_enable();
++}
++
++static inline void local_bh_enable_ip(unsigned long ip)
++{
++ __local_bh_enable();
++}
++
++#else
++
+ #ifdef CONFIG_TRACE_IRQFLAGS
+ extern void __local_bh_disable_ip(unsigned long ip, unsigned int cnt);
+ #else
+@@ -30,5 +63,6 @@
+ {
+ __local_bh_enable_ip(_THIS_IP_, SOFTIRQ_DISABLE_OFFSET);
+ }
++#endif
+
+ #endif /* _LINUX_BH_H */
+diff -Nur linux-4.8.15.orig/include/linux/buffer_head.h linux-4.8.15/include/linux/buffer_head.h
+--- linux-4.8.15.orig/include/linux/buffer_head.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/buffer_head.h 2017-01-01 17:07:15.623400677 +0100
+@@ -75,8 +75,50 @@
+ struct address_space *b_assoc_map; /* mapping this buffer is
+ associated with */
+ atomic_t b_count; /* users using this buffer_head */
++#ifdef CONFIG_PREEMPT_RT_BASE
++ spinlock_t b_uptodate_lock;
++#if IS_ENABLED(CONFIG_JBD2)
++ spinlock_t b_state_lock;
++ spinlock_t b_journal_head_lock;
++#endif
++#endif
+ };
+
++static inline unsigned long bh_uptodate_lock_irqsave(struct buffer_head *bh)
++{
++ unsigned long flags;
++
++#ifndef CONFIG_PREEMPT_RT_BASE
++ local_irq_save(flags);
++ bit_spin_lock(BH_Uptodate_Lock, &bh->b_state);
++#else
++ spin_lock_irqsave(&bh->b_uptodate_lock, flags);
++#endif
++ return flags;
++}
++
++static inline void
++bh_uptodate_unlock_irqrestore(struct buffer_head *bh, unsigned long flags)
++{
++#ifndef CONFIG_PREEMPT_RT_BASE
++ bit_spin_unlock(BH_Uptodate_Lock, &bh->b_state);
++ local_irq_restore(flags);
++#else
++ spin_unlock_irqrestore(&bh->b_uptodate_lock, flags);
++#endif
++}
++
++static inline void buffer_head_init_locks(struct buffer_head *bh)
++{
++#ifdef CONFIG_PREEMPT_RT_BASE
++ spin_lock_init(&bh->b_uptodate_lock);
++#if IS_ENABLED(CONFIG_JBD2)
++ spin_lock_init(&bh->b_state_lock);
++ spin_lock_init(&bh->b_journal_head_lock);
++#endif
++#endif
++}
++
+ /*
+ * macro tricks to expand the set_buffer_foo(), clear_buffer_foo()
+ * and buffer_foo() functions.
+diff -Nur linux-4.8.15.orig/include/linux/cgroup-defs.h linux-4.8.15/include/linux/cgroup-defs.h
+--- linux-4.8.15.orig/include/linux/cgroup-defs.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/cgroup-defs.h 2017-01-01 17:07:15.631401192 +0100
+@@ -16,6 +16,7 @@
+ #include <linux/percpu-refcount.h>
+ #include <linux/percpu-rwsem.h>
+ #include <linux/workqueue.h>
++#include <linux/swork.h>
+
+ #ifdef CONFIG_CGROUPS
+
+@@ -137,6 +138,7 @@
+ /* percpu_ref killing and RCU release */
+ struct rcu_head rcu_head;
+ struct work_struct destroy_work;
++ struct swork_event destroy_swork;
+ };
+
+ /*
+diff -Nur linux-4.8.15.orig/include/linux/completion.h linux-4.8.15/include/linux/completion.h
+--- linux-4.8.15.orig/include/linux/completion.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/completion.h 2017-01-01 17:07:15.659402994 +0100
+@@ -7,8 +7,7 @@
+ * Atomic wait-for-completion handler data structures.
+ * See kernel/sched/completion.c for details.
+ */
+-
+-#include <linux/wait.h>
++#include <linux/swait.h>
+
+ /*
+ * struct completion - structure used to maintain state for a "completion"
+@@ -24,11 +23,11 @@
+ */
+ struct completion {
+ unsigned int done;
+- wait_queue_head_t wait;
++ struct swait_queue_head wait;
+ };
+
+ #define COMPLETION_INITIALIZER(work) \
+- { 0, __WAIT_QUEUE_HEAD_INITIALIZER((work).wait) }
++ { 0, __SWAIT_QUEUE_HEAD_INITIALIZER((work).wait) }
+
+ #define COMPLETION_INITIALIZER_ONSTACK(work) \
+ ({ init_completion(&work); work; })
+@@ -73,7 +72,7 @@
+ static inline void init_completion(struct completion *x)
+ {
+ x->done = 0;
+- init_waitqueue_head(&x->wait);
++ init_swait_queue_head(&x->wait);
+ }
+
+ /**
+diff -Nur linux-4.8.15.orig/include/linux/cpu.h linux-4.8.15/include/linux/cpu.h
+--- linux-4.8.15.orig/include/linux/cpu.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/cpu.h 2017-01-01 17:07:15.703405827 +0100
+@@ -194,6 +194,8 @@
+ extern void put_online_cpus(void);
+ extern void cpu_hotplug_disable(void);
+ extern void cpu_hotplug_enable(void);
++extern void pin_current_cpu(void);
++extern void unpin_current_cpu(void);
+ #define hotcpu_notifier(fn, pri) cpu_notifier(fn, pri)
+ #define __hotcpu_notifier(fn, pri) __cpu_notifier(fn, pri)
+ #define register_hotcpu_notifier(nb) register_cpu_notifier(nb)
+@@ -211,6 +213,8 @@
+ #define put_online_cpus() do { } while (0)
+ #define cpu_hotplug_disable() do { } while (0)
+ #define cpu_hotplug_enable() do { } while (0)
++static inline void pin_current_cpu(void) { }
++static inline void unpin_current_cpu(void) { }
+ #define hotcpu_notifier(fn, pri) do { (void)(fn); } while (0)
+ #define __hotcpu_notifier(fn, pri) do { (void)(fn); } while (0)
+ /* These aren't inline functions due to a GCC bug. */
+diff -Nur linux-4.8.15.orig/include/linux/dcache.h linux-4.8.15/include/linux/dcache.h
+--- linux-4.8.15.orig/include/linux/dcache.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/dcache.h 2017-01-01 17:07:15.719406860 +0100
+@@ -11,6 +11,7 @@
+ #include <linux/rcupdate.h>
+ #include <linux/lockref.h>
+ #include <linux/stringhash.h>
++#include <linux/wait.h>
+
+ struct path;
+ struct vfsmount;
+@@ -100,7 +101,7 @@
+
+ union {
+ struct list_head d_lru; /* LRU list */
+- wait_queue_head_t *d_wait; /* in-lookup ones only */
++ struct swait_queue_head *d_wait; /* in-lookup ones only */
+ };
+ struct list_head d_child; /* child of parent list */
+ struct list_head d_subdirs; /* our children */
+@@ -230,7 +231,7 @@
+ extern struct dentry * d_alloc(struct dentry *, const struct qstr *);
+ extern struct dentry * d_alloc_pseudo(struct super_block *, const struct qstr *);
+ extern struct dentry * d_alloc_parallel(struct dentry *, const struct qstr *,
+- wait_queue_head_t *);
++ struct swait_queue_head *);
+ extern struct dentry * d_splice_alias(struct inode *, struct dentry *);
+ extern struct dentry * d_add_ci(struct dentry *, struct inode *, struct qstr *);
+ extern struct dentry * d_exact_alias(struct dentry *, struct inode *);
+diff -Nur linux-4.8.15.orig/include/linux/delay.h linux-4.8.15/include/linux/delay.h
+--- linux-4.8.15.orig/include/linux/delay.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/delay.h 2017-01-01 17:07:15.719406860 +0100
+@@ -52,4 +52,10 @@
+ msleep(seconds * 1000);
+ }
+
++#ifdef CONFIG_PREEMPT_RT_FULL
++extern void cpu_chill(void);
++#else
++# define cpu_chill() cpu_relax()
++#endif
++
+ #endif /* defined(_LINUX_DELAY_H) */
+diff -Nur linux-4.8.15.orig/include/linux/ftrace.h linux-4.8.15/include/linux/ftrace.h
+--- linux-4.8.15.orig/include/linux/ftrace.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/ftrace.h 2017-01-01 17:07:15.743408406 +0100
+@@ -714,6 +714,7 @@
+ #define CALLER_ADDR5 ((unsigned long)ftrace_return_address(5))
+ #define CALLER_ADDR6 ((unsigned long)ftrace_return_address(6))
+
++#ifdef CONFIG_USING_GET_LOCK_PARENT_IP
+ static inline unsigned long get_lock_parent_ip(void)
+ {
+ unsigned long addr = CALLER_ADDR0;
+@@ -725,6 +726,7 @@
+ return addr;
+ return CALLER_ADDR2;
+ }
++#endif
+
+ #ifdef CONFIG_IRQSOFF_TRACER
+ extern void time_hardirqs_on(unsigned long a0, unsigned long a1);
+diff -Nur linux-4.8.15.orig/include/linux/highmem.h linux-4.8.15/include/linux/highmem.h
+--- linux-4.8.15.orig/include/linux/highmem.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/highmem.h 2017-01-01 17:07:15.743408406 +0100
+@@ -7,6 +7,7 @@
+ #include <linux/mm.h>
+ #include <linux/uaccess.h>
+ #include <linux/hardirq.h>
++#include <linux/sched.h>
+
+ #include <asm/cacheflush.h>
+
+@@ -65,7 +66,7 @@
+
+ static inline void *kmap_atomic(struct page *page)
+ {
+- preempt_disable();
++ preempt_disable_nort();
+ pagefault_disable();
+ return page_address(page);
+ }
+@@ -74,7 +75,7 @@
+ static inline void __kunmap_atomic(void *addr)
+ {
+ pagefault_enable();
+- preempt_enable();
++ preempt_enable_nort();
+ }
+
+ #define kmap_atomic_pfn(pfn) kmap_atomic(pfn_to_page(pfn))
+@@ -86,32 +87,51 @@
+
+ #if defined(CONFIG_HIGHMEM) || defined(CONFIG_X86_32)
+
++#ifndef CONFIG_PREEMPT_RT_FULL
+ DECLARE_PER_CPU(int, __kmap_atomic_idx);
++#endif
+
+ static inline int kmap_atomic_idx_push(void)
+ {
++#ifndef CONFIG_PREEMPT_RT_FULL
+ int idx = __this_cpu_inc_return(__kmap_atomic_idx) - 1;
+
+-#ifdef CONFIG_DEBUG_HIGHMEM
++# ifdef CONFIG_DEBUG_HIGHMEM
+ WARN_ON_ONCE(in_irq() && !irqs_disabled());
+ BUG_ON(idx >= KM_TYPE_NR);
+-#endif
++# endif
+ return idx;
++#else
++ current->kmap_idx++;
++ BUG_ON(current->kmap_idx > KM_TYPE_NR);
++ return current->kmap_idx - 1;
++#endif
+ }
+
+ static inline int kmap_atomic_idx(void)
+ {
++#ifndef CONFIG_PREEMPT_RT_FULL
+ return __this_cpu_read(__kmap_atomic_idx) - 1;
++#else
++ return current->kmap_idx - 1;
++#endif
+ }
+
+ static inline void kmap_atomic_idx_pop(void)
+ {
+-#ifdef CONFIG_DEBUG_HIGHMEM
++#ifndef CONFIG_PREEMPT_RT_FULL
++# ifdef CONFIG_DEBUG_HIGHMEM
+ int idx = __this_cpu_dec_return(__kmap_atomic_idx);
+
+ BUG_ON(idx < 0);
+-#else
++# else
+ __this_cpu_dec(__kmap_atomic_idx);
++# endif
++#else
++ current->kmap_idx--;
++# ifdef CONFIG_DEBUG_HIGHMEM
++ BUG_ON(current->kmap_idx < 0);
++# endif
+ #endif
+ }
+
+diff -Nur linux-4.8.15.orig/include/linux/hrtimer.h linux-4.8.15/include/linux/hrtimer.h
+--- linux-4.8.15.orig/include/linux/hrtimer.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/hrtimer.h 2017-01-01 17:07:15.751408919 +0100
+@@ -87,6 +87,9 @@
+ * @function: timer expiry callback function
+ * @base: pointer to the timer base (per cpu and per clock)
+ * @state: state information (See bit values above)
++ * @cb_entry: list entry to defer timers from hardirq context
++ * @irqsafe: timer can run in hardirq context
++ * @praecox: timer expiry time if expired at the time of programming
+ * @is_rel: Set if the timer was armed relative
+ * @start_pid: timer statistics field to store the pid of the task which
+ * started the timer
+@@ -103,6 +106,11 @@
+ enum hrtimer_restart (*function)(struct hrtimer *);
+ struct hrtimer_clock_base *base;
+ u8 state;
++ struct list_head cb_entry;
++ int irqsafe;
++#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST
++ ktime_t praecox;
++#endif
+ u8 is_rel;
+ #ifdef CONFIG_TIMER_STATS
+ int start_pid;
+@@ -123,11 +131,7 @@
+ struct task_struct *task;
+ };
+
+-#ifdef CONFIG_64BIT
+ # define HRTIMER_CLOCK_BASE_ALIGN 64
+-#else
+-# define HRTIMER_CLOCK_BASE_ALIGN 32
+-#endif
+
+ /**
+ * struct hrtimer_clock_base - the timer base for a specific clock
+@@ -136,6 +140,7 @@
+ * timer to a base on another cpu.
+ * @clockid: clock id for per_cpu support
+ * @active: red black tree root node for the active timers
++ * @expired: list head for deferred timers.
+ * @get_time: function to retrieve the current time of the clock
+ * @offset: offset of this clock to the monotonic base
+ */
+@@ -144,6 +149,7 @@
+ int index;
+ clockid_t clockid;
+ struct timerqueue_head active;
++ struct list_head expired;
+ ktime_t (*get_time)(void);
+ ktime_t offset;
+ } __attribute__((__aligned__(HRTIMER_CLOCK_BASE_ALIGN)));
+@@ -187,6 +193,7 @@
+ raw_spinlock_t lock;
+ seqcount_t seq;
+ struct hrtimer *running;
++ struct hrtimer *running_soft;
+ unsigned int cpu;
+ unsigned int active_bases;
+ unsigned int clock_was_set_seq;
+@@ -203,6 +210,9 @@
+ unsigned int nr_hangs;
+ unsigned int max_hang_time;
+ #endif
++#ifdef CONFIG_PREEMPT_RT_BASE
++ wait_queue_head_t wait;
++#endif
+ struct hrtimer_clock_base clock_base[HRTIMER_MAX_CLOCK_BASES];
+ } ____cacheline_aligned;
+
+@@ -412,6 +422,13 @@
+ hrtimer_start_expires(timer, HRTIMER_MODE_ABS);
+ }
+
++/* Softirq preemption could deadlock timer removal */
++#ifdef CONFIG_PREEMPT_RT_BASE
++ extern void hrtimer_wait_for_timer(const struct hrtimer *timer);
++#else
++# define hrtimer_wait_for_timer(timer) do { cpu_relax(); } while (0)
++#endif
++
+ /* Query timers: */
+ extern ktime_t __hrtimer_get_remaining(const struct hrtimer *timer, bool adjust);
+
+@@ -436,7 +453,7 @@
+ * Helper function to check, whether the timer is running the callback
+ * function
+ */
+-static inline int hrtimer_callback_running(struct hrtimer *timer)
++static inline int hrtimer_callback_running(const struct hrtimer *timer)
+ {
+ return timer->base->cpu_base->running == timer;
+ }
+diff -Nur linux-4.8.15.orig/include/linux/idr.h linux-4.8.15/include/linux/idr.h
+--- linux-4.8.15.orig/include/linux/idr.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/idr.h 2017-01-01 17:07:15.751408919 +0100
+@@ -95,10 +95,14 @@
+ * Each idr_preload() should be matched with an invocation of this
+ * function. See idr_preload() for details.
+ */
++#ifdef CONFIG_PREEMPT_RT_FULL
++void idr_preload_end(void);
++#else
+ static inline void idr_preload_end(void)
+ {
+ preempt_enable();
+ }
++#endif
+
+ /**
+ * idr_find - return pointer for given id
+diff -Nur linux-4.8.15.orig/include/linux/init_task.h linux-4.8.15/include/linux/init_task.h
+--- linux-4.8.15.orig/include/linux/init_task.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/init_task.h 2017-01-01 17:07:15.751408919 +0100
+@@ -148,6 +148,12 @@
+ # define INIT_PERF_EVENTS(tsk)
+ #endif
+
++#ifdef CONFIG_PREEMPT_RT_BASE
++# define INIT_TIMER_LIST .posix_timer_list = NULL,
++#else
++# define INIT_TIMER_LIST
++#endif
++
+ #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
+ # define INIT_VTIME(tsk) \
+ .vtime_seqcount = SEQCNT_ZERO(tsk.vtime_seqcount), \
+@@ -239,6 +245,7 @@
+ .cpu_timers = INIT_CPU_TIMERS(tsk.cpu_timers), \
+ .pi_lock = __RAW_SPIN_LOCK_UNLOCKED(tsk.pi_lock), \
+ .timer_slack_ns = 50000, /* 50 usec default slack */ \
++ INIT_TIMER_LIST \
+ .pids = { \
+ [PIDTYPE_PID] = INIT_PID_LINK(PIDTYPE_PID), \
+ [PIDTYPE_PGID] = INIT_PID_LINK(PIDTYPE_PGID), \
+diff -Nur linux-4.8.15.orig/include/linux/interrupt.h linux-4.8.15/include/linux/interrupt.h
+--- linux-4.8.15.orig/include/linux/interrupt.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/interrupt.h 2017-01-01 17:07:15.759409443 +0100
+@@ -14,6 +14,7 @@
+ #include <linux/hrtimer.h>
+ #include <linux/kref.h>
+ #include <linux/workqueue.h>
++#include <linux/swork.h>
+
+ #include <linux/atomic.h>
+ #include <asm/ptrace.h>
+@@ -61,6 +62,7 @@
+ * interrupt handler after suspending interrupts. For system
+ * wakeup devices users need to implement wakeup detection in
+ * their interrupt handlers.
++ * IRQF_NO_SOFTIRQ_CALL - Do not process softirqs in the irq thread context (RT)
+ */
+ #define IRQF_SHARED 0x00000080
+ #define IRQF_PROBE_SHARED 0x00000100
+@@ -74,6 +76,7 @@
+ #define IRQF_NO_THREAD 0x00010000
+ #define IRQF_EARLY_RESUME 0x00020000
+ #define IRQF_COND_SUSPEND 0x00040000
++#define IRQF_NO_SOFTIRQ_CALL 0x00080000
+
+ #define IRQF_TIMER (__IRQF_TIMER | IRQF_NO_SUSPEND | IRQF_NO_THREAD)
+
+@@ -196,7 +199,7 @@
+ #ifdef CONFIG_LOCKDEP
+ # define local_irq_enable_in_hardirq() do { } while (0)
+ #else
+-# define local_irq_enable_in_hardirq() local_irq_enable()
++# define local_irq_enable_in_hardirq() local_irq_enable_nort()
+ #endif
+
+ extern void disable_irq_nosync(unsigned int irq);
+@@ -216,6 +219,7 @@
+ * struct irq_affinity_notify - context for notification of IRQ affinity changes
+ * @irq: Interrupt to which notification applies
+ * @kref: Reference count, for internal use
++ * @swork: Swork item, for internal use
+ * @work: Work item, for internal use
+ * @notify: Function to be called on change. This will be
+ * called in process context.
+@@ -227,7 +231,11 @@
+ struct irq_affinity_notify {
+ unsigned int irq;
+ struct kref kref;
++#ifdef CONFIG_PREEMPT_RT_BASE
++ struct swork_event swork;
++#else
+ struct work_struct work;
++#endif
+ void (*notify)(struct irq_affinity_notify *, const cpumask_t *mask);
+ void (*release)(struct kref *ref);
+ };
+@@ -398,9 +406,13 @@
+ bool state);
+
+ #ifdef CONFIG_IRQ_FORCED_THREADING
++# ifndef CONFIG_PREEMPT_RT_BASE
+ extern bool force_irqthreads;
++# else
++# define force_irqthreads (true)
++# endif
+ #else
+-#define force_irqthreads (0)
++#define force_irqthreads (false)
+ #endif
+
+ #ifndef __ARCH_SET_SOFTIRQ_PENDING
+@@ -457,9 +469,10 @@
+ void (*action)(struct softirq_action *);
+ };
+
++#ifndef CONFIG_PREEMPT_RT_FULL
+ asmlinkage void do_softirq(void);
+ asmlinkage void __do_softirq(void);
+-
++static inline void thread_do_softirq(void) { do_softirq(); }
+ #ifdef __ARCH_HAS_DO_SOFTIRQ
+ void do_softirq_own_stack(void);
+ #else
+@@ -468,13 +481,25 @@
+ __do_softirq();
+ }
+ #endif
++#else
++extern void thread_do_softirq(void);
++#endif
+
+ extern void open_softirq(int nr, void (*action)(struct softirq_action *));
+ extern void softirq_init(void);
+ extern void __raise_softirq_irqoff(unsigned int nr);
++#ifdef CONFIG_PREEMPT_RT_FULL
++extern void __raise_softirq_irqoff_ksoft(unsigned int nr);
++#else
++static inline void __raise_softirq_irqoff_ksoft(unsigned int nr)
++{
++ __raise_softirq_irqoff(nr);
++}
++#endif
+
+ extern void raise_softirq_irqoff(unsigned int nr);
+ extern void raise_softirq(unsigned int nr);
++extern void softirq_check_pending_idle(void);
+
+ DECLARE_PER_CPU(struct task_struct *, ksoftirqd);
+
+@@ -496,8 +521,9 @@
+ to be executed on some cpu at least once after this.
+ * If the tasklet is already scheduled, but its execution is still not
+ started, it will be executed only once.
+- * If this tasklet is already running on another CPU (or schedule is called
+- from tasklet itself), it is rescheduled for later.
++ * If this tasklet is already running on another CPU, it is rescheduled
++ for later.
++ * Schedule must not be called from the tasklet itself (a lockup occurs)
+ * Tasklet is strictly serialized wrt itself, but not
+ wrt another tasklets. If client needs some intertask synchronization,
+ he makes it with spinlocks.
+@@ -522,27 +548,36 @@
+ enum
+ {
+ TASKLET_STATE_SCHED, /* Tasklet is scheduled for execution */
+- TASKLET_STATE_RUN /* Tasklet is running (SMP only) */
++ TASKLET_STATE_RUN, /* Tasklet is running (SMP only) */
++ TASKLET_STATE_PENDING /* Tasklet is pending */
+ };
+
+-#ifdef CONFIG_SMP
++#define TASKLET_STATEF_SCHED (1 << TASKLET_STATE_SCHED)
++#define TASKLET_STATEF_RUN (1 << TASKLET_STATE_RUN)
++#define TASKLET_STATEF_PENDING (1 << TASKLET_STATE_PENDING)
++
++#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT_FULL)
+ static inline int tasklet_trylock(struct tasklet_struct *t)
+ {
+ return !test_and_set_bit(TASKLET_STATE_RUN, &(t)->state);
+ }
+
++static inline int tasklet_tryunlock(struct tasklet_struct *t)
++{
++ return cmpxchg(&t->state, TASKLET_STATEF_RUN, 0) == TASKLET_STATEF_RUN;
++}
++
+ static inline void tasklet_unlock(struct tasklet_struct *t)
+ {
+ smp_mb__before_atomic();
+ clear_bit(TASKLET_STATE_RUN, &(t)->state);
+ }
+
+-static inline void tasklet_unlock_wait(struct tasklet_struct *t)
+-{
+- while (test_bit(TASKLET_STATE_RUN, &(t)->state)) { barrier(); }
+-}
++extern void tasklet_unlock_wait(struct tasklet_struct *t);
++
+ #else
+ #define tasklet_trylock(t) 1
++#define tasklet_tryunlock(t) 1
+ #define tasklet_unlock_wait(t) do { } while (0)
+ #define tasklet_unlock(t) do { } while (0)
+ #endif
+@@ -591,12 +626,7 @@
+ smp_mb();
+ }
+
+-static inline void tasklet_enable(struct tasklet_struct *t)
+-{
+- smp_mb__before_atomic();
+- atomic_dec(&t->count);
+-}
+-
++extern void tasklet_enable(struct tasklet_struct *t);
+ extern void tasklet_kill(struct tasklet_struct *t);
+ extern void tasklet_kill_immediate(struct tasklet_struct *t, unsigned int cpu);
+ extern void tasklet_init(struct tasklet_struct *t,
+@@ -627,6 +657,12 @@
+ tasklet_kill(&ttimer->tasklet);
+ }
+
++#ifdef CONFIG_PREEMPT_RT_FULL
++extern void softirq_early_init(void);
++#else
++static inline void softirq_early_init(void) { }
++#endif
++
+ /*
+ * Autoprobing for irqs:
+ *
+diff -Nur linux-4.8.15.orig/include/linux/irqdesc.h linux-4.8.15/include/linux/irqdesc.h
+--- linux-4.8.15.orig/include/linux/irqdesc.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/irqdesc.h 2017-01-01 17:07:15.771410216 +0100
+@@ -64,6 +64,7 @@
+ unsigned int irqs_unhandled;
+ atomic_t threads_handled;
+ int threads_handled_last;
++ u64 random_ip;
+ raw_spinlock_t lock;
+ struct cpumask *percpu_enabled;
+ const struct cpumask *percpu_affinity;
+diff -Nur linux-4.8.15.orig/include/linux/irqflags.h linux-4.8.15/include/linux/irqflags.h
+--- linux-4.8.15.orig/include/linux/irqflags.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/irqflags.h 2017-01-01 17:07:15.771410216 +0100
+@@ -25,8 +25,6 @@
+ # define trace_softirqs_enabled(p) ((p)->softirqs_enabled)
+ # define trace_hardirq_enter() do { current->hardirq_context++; } while (0)
+ # define trace_hardirq_exit() do { current->hardirq_context--; } while (0)
+-# define lockdep_softirq_enter() do { current->softirq_context++; } while (0)
+-# define lockdep_softirq_exit() do { current->softirq_context--; } while (0)
+ # define INIT_TRACE_IRQFLAGS .softirqs_enabled = 1,
+ #else
+ # define trace_hardirqs_on() do { } while (0)
+@@ -39,9 +37,15 @@
+ # define trace_softirqs_enabled(p) 0
+ # define trace_hardirq_enter() do { } while (0)
+ # define trace_hardirq_exit() do { } while (0)
++# define INIT_TRACE_IRQFLAGS
++#endif
++
++#if defined(CONFIG_TRACE_IRQFLAGS) && !defined(CONFIG_PREEMPT_RT_FULL)
++# define lockdep_softirq_enter() do { current->softirq_context++; } while (0)
++# define lockdep_softirq_exit() do { current->softirq_context--; } while (0)
++#else
+ # define lockdep_softirq_enter() do { } while (0)
+ # define lockdep_softirq_exit() do { } while (0)
+-# define INIT_TRACE_IRQFLAGS
+ #endif
+
+ #if defined(CONFIG_IRQSOFF_TRACER) || \
+@@ -148,4 +152,23 @@
+
+ #define irqs_disabled_flags(flags) raw_irqs_disabled_flags(flags)
+
++/*
++ * local_irq* variants depending on RT/!RT
++ */
++#ifdef CONFIG_PREEMPT_RT_FULL
++# define local_irq_disable_nort() do { } while (0)
++# define local_irq_enable_nort() do { } while (0)
++# define local_irq_save_nort(flags) local_save_flags(flags)
++# define local_irq_restore_nort(flags) (void)(flags)
++# define local_irq_disable_rt() local_irq_disable()
++# define local_irq_enable_rt() local_irq_enable()
++#else
++# define local_irq_disable_nort() local_irq_disable()
++# define local_irq_enable_nort() local_irq_enable()
++# define local_irq_save_nort(flags) local_irq_save(flags)
++# define local_irq_restore_nort(flags) local_irq_restore(flags)
++# define local_irq_disable_rt() do { } while (0)
++# define local_irq_enable_rt() do { } while (0)
++#endif
++
+ #endif
+diff -Nur linux-4.8.15.orig/include/linux/irq.h linux-4.8.15/include/linux/irq.h
+--- linux-4.8.15.orig/include/linux/irq.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/irq.h 2017-01-01 17:07:15.767409952 +0100
+@@ -72,6 +72,7 @@
+ * IRQ_IS_POLLED - Always polled by another interrupt. Exclude
+ * it from the spurious interrupt detection
+ * mechanism and from core side polling.
++ * IRQ_NO_SOFTIRQ_CALL - No softirq processing in the irq thread context (RT)
+ * IRQ_DISABLE_UNLAZY - Disable lazy irq disable
+ */
+ enum {
+@@ -99,13 +100,14 @@
+ IRQ_PER_CPU_DEVID = (1 << 17),
+ IRQ_IS_POLLED = (1 << 18),
+ IRQ_DISABLE_UNLAZY = (1 << 19),
++ IRQ_NO_SOFTIRQ_CALL = (1 << 20),
+ };
+
+ #define IRQF_MODIFY_MASK \
+ (IRQ_TYPE_SENSE_MASK | IRQ_NOPROBE | IRQ_NOREQUEST | \
+ IRQ_NOAUTOEN | IRQ_MOVE_PCNTXT | IRQ_LEVEL | IRQ_NO_BALANCING | \
+ IRQ_PER_CPU | IRQ_NESTED_THREAD | IRQ_NOTHREAD | IRQ_PER_CPU_DEVID | \
+- IRQ_IS_POLLED | IRQ_DISABLE_UNLAZY)
++ IRQ_IS_POLLED | IRQ_DISABLE_UNLAZY | IRQ_NO_SOFTIRQ_CALL)
+
+ #define IRQ_NO_BALANCING_MASK (IRQ_PER_CPU | IRQ_NO_BALANCING)
+
+diff -Nur linux-4.8.15.orig/include/linux/irq_work.h linux-4.8.15/include/linux/irq_work.h
+--- linux-4.8.15.orig/include/linux/irq_work.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/irq_work.h 2017-01-01 17:07:15.767409952 +0100
+@@ -16,6 +16,7 @@
+ #define IRQ_WORK_BUSY 2UL
+ #define IRQ_WORK_FLAGS 3UL
+ #define IRQ_WORK_LAZY 4UL /* Doesn't want IPI, wait for tick */
++#define IRQ_WORK_HARD_IRQ 8UL /* Run hard IRQ context, even on RT */
+
+ struct irq_work {
+ unsigned long flags;
+@@ -51,4 +52,10 @@
+ static inline void irq_work_run(void) { }
+ #endif
+
++#if defined(CONFIG_IRQ_WORK) && defined(CONFIG_PREEMPT_RT_FULL)
++void irq_work_tick_soft(void);
++#else
++static inline void irq_work_tick_soft(void) { }
++#endif
++
+ #endif /* _LINUX_IRQ_WORK_H */
+diff -Nur linux-4.8.15.orig/include/linux/jbd2.h linux-4.8.15/include/linux/jbd2.h
+--- linux-4.8.15.orig/include/linux/jbd2.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/jbd2.h 2017-01-01 17:07:15.775410464 +0100
+@@ -347,32 +347,56 @@
+
+ static inline void jbd_lock_bh_state(struct buffer_head *bh)
+ {
++#ifndef CONFIG_PREEMPT_RT_BASE
+ bit_spin_lock(BH_State, &bh->b_state);
++#else
++ spin_lock(&bh->b_state_lock);
++#endif
+ }
+
+ static inline int jbd_trylock_bh_state(struct buffer_head *bh)
+ {
++#ifndef CONFIG_PREEMPT_RT_BASE
+ return bit_spin_trylock(BH_State, &bh->b_state);
++#else
++ return spin_trylock(&bh->b_state_lock);
++#endif
+ }
+
+ static inline int jbd_is_locked_bh_state(struct buffer_head *bh)
+ {
++#ifndef CONFIG_PREEMPT_RT_BASE
+ return bit_spin_is_locked(BH_State, &bh->b_state);
++#else
++ return spin_is_locked(&bh->b_state_lock);
++#endif
+ }
+
+ static inline void jbd_unlock_bh_state(struct buffer_head *bh)
+ {
++#ifndef CONFIG_PREEMPT_RT_BASE
+ bit_spin_unlock(BH_State, &bh->b_state);
++#else
++ spin_unlock(&bh->b_state_lock);
++#endif
+ }
+
+ static inline void jbd_lock_bh_journal_head(struct buffer_head *bh)
+ {
++#ifndef CONFIG_PREEMPT_RT_BASE
+ bit_spin_lock(BH_JournalHead, &bh->b_state);
++#else
++ spin_lock(&bh->b_journal_head_lock);
++#endif
+ }
+
+ static inline void jbd_unlock_bh_journal_head(struct buffer_head *bh)
+ {
++#ifndef CONFIG_PREEMPT_RT_BASE
+ bit_spin_unlock(BH_JournalHead, &bh->b_state);
++#else
++ spin_unlock(&bh->b_journal_head_lock);
++#endif
+ }
+
+ #define J_ASSERT(assert) BUG_ON(!(assert))
+diff -Nur linux-4.8.15.orig/include/linux/kdb.h linux-4.8.15/include/linux/kdb.h
+--- linux-4.8.15.orig/include/linux/kdb.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/kdb.h 2017-01-01 17:07:15.775410464 +0100
+@@ -167,6 +167,7 @@
+ extern __printf(1, 2) int kdb_printf(const char *, ...);
+ typedef __printf(1, 2) int (*kdb_printf_t)(const char *, ...);
+
++#define in_kdb_printk() (kdb_trap_printk)
+ extern void kdb_init(int level);
+
+ /* Access to kdb specific polling devices */
+@@ -201,6 +202,7 @@
+ extern int kdb_unregister(char *);
+ #else /* ! CONFIG_KGDB_KDB */
+ static inline __printf(1, 2) int kdb_printf(const char *fmt, ...) { return 0; }
++#define in_kdb_printk() (0)
+ static inline void kdb_init(int level) {}
+ static inline int kdb_register(char *cmd, kdb_func_t func, char *usage,
+ char *help, short minlen) { return 0; }
+diff -Nur linux-4.8.15.orig/include/linux/kernel.h linux-4.8.15/include/linux/kernel.h
+--- linux-4.8.15.orig/include/linux/kernel.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/kernel.h 2017-01-01 17:07:15.775410464 +0100
+@@ -194,6 +194,9 @@
+ */
+ # define might_sleep() \
+ do { __might_sleep(__FILE__, __LINE__, 0); might_resched(); } while (0)
++
++# define might_sleep_no_state_check() \
++ do { ___might_sleep(__FILE__, __LINE__, 0); might_resched(); } while (0)
+ # define sched_annotate_sleep() (current->task_state_change = 0)
+ #else
+ static inline void ___might_sleep(const char *file, int line,
+@@ -201,6 +204,7 @@
+ static inline void __might_sleep(const char *file, int line,
+ int preempt_offset) { }
+ # define might_sleep() do { might_resched(); } while (0)
++# define might_sleep_no_state_check() do { might_resched(); } while (0)
+ # define sched_annotate_sleep() do { } while (0)
+ #endif
+
+@@ -491,6 +495,7 @@
+ SYSTEM_HALT,
+ SYSTEM_POWER_OFF,
+ SYSTEM_RESTART,
++ SYSTEM_SUSPEND,
+ } system_state;
+
+ #define TAINT_PROPRIETARY_MODULE 0
+diff -Nur linux-4.8.15.orig/include/linux/lglock.h linux-4.8.15/include/linux/lglock.h
+--- linux-4.8.15.orig/include/linux/lglock.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/lglock.h 2017-01-01 17:07:15.779410723 +0100
+@@ -34,13 +34,30 @@
+ #endif
+
+ struct lglock {
++#ifdef CONFIG_PREEMPT_RT_FULL
++ struct rt_mutex __percpu *lock;
++#else
+ arch_spinlock_t __percpu *lock;
++#endif
+ #ifdef CONFIG_DEBUG_LOCK_ALLOC
+ struct lock_class_key lock_key;
+ struct lockdep_map lock_dep_map;
+ #endif
+ };
+
++#ifdef CONFIG_PREEMPT_RT_FULL
++# define DEFINE_LGLOCK(name) \
++ static DEFINE_PER_CPU(struct rt_mutex, name ## _lock) \
++ = __RT_MUTEX_INITIALIZER( name ## _lock); \
++ struct lglock name = { .lock = &name ## _lock }
++
++# define DEFINE_STATIC_LGLOCK(name) \
++ static DEFINE_PER_CPU(struct rt_mutex, name ## _lock) \
++ = __RT_MUTEX_INITIALIZER( name ## _lock); \
++ static struct lglock name = { .lock = &name ## _lock }
++
++#else
++
+ #define DEFINE_LGLOCK(name) \
+ static DEFINE_PER_CPU(arch_spinlock_t, name ## _lock) \
+ = __ARCH_SPIN_LOCK_UNLOCKED; \
+@@ -50,6 +67,7 @@
+ static DEFINE_PER_CPU(arch_spinlock_t, name ## _lock) \
+ = __ARCH_SPIN_LOCK_UNLOCKED; \
+ static struct lglock name = { .lock = &name ## _lock }
++#endif
+
+ void lg_lock_init(struct lglock *lg, char *name);
+
+@@ -64,6 +82,12 @@
+ void lg_global_lock(struct lglock *lg);
+ void lg_global_unlock(struct lglock *lg);
+
++#ifndef CONFIG_PREEMPT_RT_FULL
++#define lg_global_trylock_relax(name) lg_global_lock(name)
++#else
++void lg_global_trylock_relax(struct lglock *lg);
++#endif
++
+ #else
+ /* When !CONFIG_SMP, map lglock to spinlock */
+ #define lglock spinlock
+diff -Nur linux-4.8.15.orig/include/linux/list_bl.h linux-4.8.15/include/linux/list_bl.h
+--- linux-4.8.15.orig/include/linux/list_bl.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/list_bl.h 2017-01-01 17:07:15.779410723 +0100
+@@ -2,6 +2,7 @@
+ #define _LINUX_LIST_BL_H
+
+ #include <linux/list.h>
++#include <linux/spinlock.h>
+ #include <linux/bit_spinlock.h>
+
+ /*
+@@ -32,13 +33,24 @@
+
+ struct hlist_bl_head {
+ struct hlist_bl_node *first;
++#ifdef CONFIG_PREEMPT_RT_BASE
++ raw_spinlock_t lock;
++#endif
+ };
+
+ struct hlist_bl_node {
+ struct hlist_bl_node *next, **pprev;
+ };
+-#define INIT_HLIST_BL_HEAD(ptr) \
+- ((ptr)->first = NULL)
++
++#ifdef CONFIG_PREEMPT_RT_BASE
++#define INIT_HLIST_BL_HEAD(h) \
++do { \
++ (h)->first = NULL; \
++ raw_spin_lock_init(&(h)->lock); \
++} while (0)
++#else
++#define INIT_HLIST_BL_HEAD(h) (h)->first = NULL
++#endif
+
+ static inline void INIT_HLIST_BL_NODE(struct hlist_bl_node *h)
+ {
+@@ -118,12 +130,26 @@
+
+ static inline void hlist_bl_lock(struct hlist_bl_head *b)
+ {
++#ifndef CONFIG_PREEMPT_RT_BASE
+ bit_spin_lock(0, (unsigned long *)b);
++#else
++ raw_spin_lock(&b->lock);
++#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
++ __set_bit(0, (unsigned long *)b);
++#endif
++#endif
+ }
+
+ static inline void hlist_bl_unlock(struct hlist_bl_head *b)
+ {
++#ifndef CONFIG_PREEMPT_RT_BASE
+ __bit_spin_unlock(0, (unsigned long *)b);
++#else
++#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
++ __clear_bit(0, (unsigned long *)b);
++#endif
++ raw_spin_unlock(&b->lock);
++#endif
+ }
+
+ static inline bool hlist_bl_is_locked(struct hlist_bl_head *b)
+diff -Nur linux-4.8.15.orig/include/linux/locallock.h linux-4.8.15/include/linux/locallock.h
+--- linux-4.8.15.orig/include/linux/locallock.h 1970-01-01 01:00:00.000000000 +0100
++++ linux-4.8.15/include/linux/locallock.h 2017-01-01 17:07:15.779410723 +0100
+@@ -0,0 +1,278 @@
++#ifndef _LINUX_LOCALLOCK_H
++#define _LINUX_LOCALLOCK_H
++
++#include <linux/percpu.h>
++#include <linux/spinlock.h>
++
++#ifdef CONFIG_PREEMPT_RT_BASE
++
++#ifdef CONFIG_DEBUG_SPINLOCK
++# define LL_WARN(cond) WARN_ON(cond)
++#else
++# define LL_WARN(cond) do { } while (0)
++#endif
++
++/*
++ * per cpu lock based substitute for local_irq_*()
++ */
++struct local_irq_lock {
++ spinlock_t lock;
++ struct task_struct *owner;
++ int nestcnt;
++ unsigned long flags;
++};
++
++#define DEFINE_LOCAL_IRQ_LOCK(lvar) \
++ DEFINE_PER_CPU(struct local_irq_lock, lvar) = { \
++ .lock = __SPIN_LOCK_UNLOCKED((lvar).lock) }
++
++#define DECLARE_LOCAL_IRQ_LOCK(lvar) \
++ DECLARE_PER_CPU(struct local_irq_lock, lvar)
++
++#define local_irq_lock_init(lvar) \
++ do { \
++ int __cpu; \
++ for_each_possible_cpu(__cpu) \
++ spin_lock_init(&per_cpu(lvar, __cpu).lock); \
++ } while (0)
++
++/*
++ * spin_lock|trylock|unlock_local flavour that does not migrate disable
++ * used for __local_lock|trylock|unlock where get_local_var/put_local_var
++ * already takes care of the migrate_disable/enable
++ * for CONFIG_PREEMPT_BASE map to the normal spin_* calls.
++ */
++#ifdef CONFIG_PREEMPT_RT_FULL
++# define spin_lock_local(lock) rt_spin_lock__no_mg(lock)
++# define spin_trylock_local(lock) rt_spin_trylock__no_mg(lock)
++# define spin_unlock_local(lock) rt_spin_unlock__no_mg(lock)
++#else
++# define spin_lock_local(lock) spin_lock(lock)
++# define spin_trylock_local(lock) spin_trylock(lock)
++# define spin_unlock_local(lock) spin_unlock(lock)
++#endif
++
++static inline void __local_lock(struct local_irq_lock *lv)
++{
++ if (lv->owner != current) {
++ spin_lock_local(&lv->lock);
++ LL_WARN(lv->owner);
++ LL_WARN(lv->nestcnt);
++ lv->owner = current;
++ }
++ lv->nestcnt++;
++}
++
++#define local_lock(lvar) \
++ do { __local_lock(&get_local_var(lvar)); } while (0)
++
++#define local_lock_on(lvar, cpu) \
++ do { __local_lock(&per_cpu(lvar, cpu)); } while (0)
++
++static inline int __local_trylock(struct local_irq_lock *lv)
++{
++ if (lv->owner != current && spin_trylock_local(&lv->lock)) {
++ LL_WARN(lv->owner);
++ LL_WARN(lv->nestcnt);
++ lv->owner = current;
++ lv->nestcnt = 1;
++ return 1;
++ }
++ return 0;
++}
++
++#define local_trylock(lvar) \
++ ({ \
++ int __locked; \
++ __locked = __local_trylock(&get_local_var(lvar)); \
++ if (!__locked) \
++ put_local_var(lvar); \
++ __locked; \
++ })
++
++static inline void __local_unlock(struct local_irq_lock *lv)
++{
++ LL_WARN(lv->nestcnt == 0);
++ LL_WARN(lv->owner != current);
++ if (--lv->nestcnt)
++ return;
++
++ lv->owner = NULL;
++ spin_unlock_local(&lv->lock);
++}
++
++#define local_unlock(lvar) \
++ do { \
++ __local_unlock(this_cpu_ptr(&lvar)); \
++ put_local_var(lvar); \
++ } while (0)
++
++#define local_unlock_on(lvar, cpu) \
++ do { __local_unlock(&per_cpu(lvar, cpu)); } while (0)
++
++static inline void __local_lock_irq(struct local_irq_lock *lv)
++{
++ spin_lock_irqsave(&lv->lock, lv->flags);
++ LL_WARN(lv->owner);
++ LL_WARN(lv->nestcnt);
++ lv->owner = current;
++ lv->nestcnt = 1;
++}
++
++#define local_lock_irq(lvar) \
++ do { __local_lock_irq(&get_local_var(lvar)); } while (0)
++
++#define local_lock_irq_on(lvar, cpu) \
++ do { __local_lock_irq(&per_cpu(lvar, cpu)); } while (0)
++
++static inline void __local_unlock_irq(struct local_irq_lock *lv)
++{
++ LL_WARN(!lv->nestcnt);
++ LL_WARN(lv->owner != current);
++ lv->owner = NULL;
++ lv->nestcnt = 0;
++ spin_unlock_irq(&lv->lock);
++}
++
++#define local_unlock_irq(lvar) \
++ do { \
++ __local_unlock_irq(this_cpu_ptr(&lvar)); \
++ put_local_var(lvar); \
++ } while (0)
++
++#define local_unlock_irq_on(lvar, cpu) \
++ do { \
++ __local_unlock_irq(&per_cpu(lvar, cpu)); \
++ } while (0)
++
++static inline int __local_lock_irqsave(struct local_irq_lock *lv)
++{
++ if (lv->owner != current) {
++ __local_lock_irq(lv);
++ return 0;
++ } else {
++ lv->nestcnt++;
++ return 1;
++ }
++}
++
++#define local_lock_irqsave(lvar, _flags) \
++ do { \
++ if (__local_lock_irqsave(&get_local_var(lvar))) \
++ put_local_var(lvar); \
++ _flags = __this_cpu_read(lvar.flags); \
++ } while (0)
++
++#define local_lock_irqsave_on(lvar, _flags, cpu) \
++ do { \
++ __local_lock_irqsave(&per_cpu(lvar, cpu)); \
++ _flags = per_cpu(lvar, cpu).flags; \
++ } while (0)
++
++static inline int __local_unlock_irqrestore(struct local_irq_lock *lv,
++ unsigned long flags)
++{
++ LL_WARN(!lv->nestcnt);
++ LL_WARN(lv->owner != current);
++ if (--lv->nestcnt)
++ return 0;
++
++ lv->owner = NULL;
++ spin_unlock_irqrestore(&lv->lock, lv->flags);
++ return 1;
++}
++
++#define local_unlock_irqrestore(lvar, flags) \
++ do { \
++ if (__local_unlock_irqrestore(this_cpu_ptr(&lvar), flags)) \
++ put_local_var(lvar); \
++ } while (0)
++
++#define local_unlock_irqrestore_on(lvar, flags, cpu) \
++ do { \
++ __local_unlock_irqrestore(&per_cpu(lvar, cpu), flags); \
++ } while (0)
++
++#define local_spin_trylock_irq(lvar, lock) \
++ ({ \
++ int __locked; \
++ local_lock_irq(lvar); \
++ __locked = spin_trylock(lock); \
++ if (!__locked) \
++ local_unlock_irq(lvar); \
++ __locked; \
++ })
++
++#define local_spin_lock_irq(lvar, lock) \
++ do { \
++ local_lock_irq(lvar); \
++ spin_lock(lock); \
++ } while (0)
++
++#define local_spin_unlock_irq(lvar, lock) \
++ do { \
++ spin_unlock(lock); \
++ local_unlock_irq(lvar); \
++ } while (0)
++
++#define local_spin_lock_irqsave(lvar, lock, flags) \
++ do { \
++ local_lock_irqsave(lvar, flags); \
++ spin_lock(lock); \
++ } while (0)
++
++#define local_spin_unlock_irqrestore(lvar, lock, flags) \
++ do { \
++ spin_unlock(lock); \
++ local_unlock_irqrestore(lvar, flags); \
++ } while (0)
++
++#define get_locked_var(lvar, var) \
++ (*({ \
++ local_lock(lvar); \
++ this_cpu_ptr(&var); \
++ }))
++
++#define put_locked_var(lvar, var) local_unlock(lvar);
++
++#define local_lock_cpu(lvar) \
++ ({ \
++ local_lock(lvar); \
++ smp_processor_id(); \
++ })
++
++#define local_unlock_cpu(lvar) local_unlock(lvar)
++
++#else /* PREEMPT_RT_BASE */
++
++#define DEFINE_LOCAL_IRQ_LOCK(lvar) __typeof__(const int) lvar
++#define DECLARE_LOCAL_IRQ_LOCK(lvar) extern __typeof__(const int) lvar
++
++static inline void local_irq_lock_init(int lvar) { }
++
++#define local_lock(lvar) preempt_disable()
++#define local_unlock(lvar) preempt_enable()
++#define local_lock_irq(lvar) local_irq_disable()
++#define local_lock_irq_on(lvar, cpu) local_irq_disable()
++#define local_unlock_irq(lvar) local_irq_enable()
++#define local_unlock_irq_on(lvar, cpu) local_irq_enable()
++#define local_lock_irqsave(lvar, flags) local_irq_save(flags)
++#define local_unlock_irqrestore(lvar, flags) local_irq_restore(flags)
++
++#define local_spin_trylock_irq(lvar, lock) spin_trylock_irq(lock)
++#define local_spin_lock_irq(lvar, lock) spin_lock_irq(lock)
++#define local_spin_unlock_irq(lvar, lock) spin_unlock_irq(lock)
++#define local_spin_lock_irqsave(lvar, lock, flags) \
++ spin_lock_irqsave(lock, flags)
++#define local_spin_unlock_irqrestore(lvar, lock, flags) \
++ spin_unlock_irqrestore(lock, flags)
++
++#define get_locked_var(lvar, var) get_cpu_var(var)
++#define put_locked_var(lvar, var) put_cpu_var(var)
++
++#define local_lock_cpu(lvar) get_cpu()
++#define local_unlock_cpu(lvar) put_cpu()
++
++#endif
++
++#endif
+diff -Nur linux-4.8.15.orig/include/linux/mm_types.h linux-4.8.15/include/linux/mm_types.h
+--- linux-4.8.15.orig/include/linux/mm_types.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/mm_types.h 2017-01-01 17:07:15.791411498 +0100
+@@ -11,6 +11,7 @@
+ #include <linux/completion.h>
+ #include <linux/cpumask.h>
+ #include <linux/uprobes.h>
++#include <linux/rcupdate.h>
+ #include <linux/page-flags-layout.h>
+ #include <linux/workqueue.h>
+ #include <asm/page.h>
+@@ -508,6 +509,9 @@
+ bool tlb_flush_pending;
+ #endif
+ struct uprobes_state uprobes_state;
++#ifdef CONFIG_PREEMPT_RT_BASE
++ struct rcu_head delayed_drop;
++#endif
+ #ifdef CONFIG_X86_INTEL_MPX
+ /* address of the bounds directory */
+ void __user *bd_addr;
+diff -Nur linux-4.8.15.orig/include/linux/mutex.h linux-4.8.15/include/linux/mutex.h
+--- linux-4.8.15.orig/include/linux/mutex.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/mutex.h 2017-01-01 17:07:15.791411498 +0100
+@@ -19,6 +19,17 @@
+ #include <asm/processor.h>
+ #include <linux/osq_lock.h>
+
++#ifdef CONFIG_DEBUG_LOCK_ALLOC
++# define __DEP_MAP_MUTEX_INITIALIZER(lockname) \
++ , .dep_map = { .name = #lockname }
++#else
++# define __DEP_MAP_MUTEX_INITIALIZER(lockname)
++#endif
++
++#ifdef CONFIG_PREEMPT_RT_FULL
++# include <linux/mutex_rt.h>
++#else
++
+ /*
+ * Simple, straightforward mutexes with strict semantics:
+ *
+@@ -99,13 +110,6 @@
+ static inline void mutex_destroy(struct mutex *lock) {}
+ #endif
+
+-#ifdef CONFIG_DEBUG_LOCK_ALLOC
+-# define __DEP_MAP_MUTEX_INITIALIZER(lockname) \
+- , .dep_map = { .name = #lockname }
+-#else
+-# define __DEP_MAP_MUTEX_INITIALIZER(lockname)
+-#endif
+-
+ #define __MUTEX_INITIALIZER(lockname) \
+ { .count = ATOMIC_INIT(1) \
+ , .wait_lock = __SPIN_LOCK_UNLOCKED(lockname.wait_lock) \
+@@ -173,6 +177,8 @@
+ extern int mutex_trylock(struct mutex *lock);
+ extern void mutex_unlock(struct mutex *lock);
+
++#endif /* !PREEMPT_RT_FULL */
++
+ extern int atomic_dec_and_mutex_lock(atomic_t *cnt, struct mutex *lock);
+
+ #endif /* __LINUX_MUTEX_H */
+diff -Nur linux-4.8.15.orig/include/linux/mutex_rt.h linux-4.8.15/include/linux/mutex_rt.h
+--- linux-4.8.15.orig/include/linux/mutex_rt.h 1970-01-01 01:00:00.000000000 +0100
++++ linux-4.8.15/include/linux/mutex_rt.h 2017-01-01 17:07:15.791411498 +0100
+@@ -0,0 +1,84 @@
++#ifndef __LINUX_MUTEX_RT_H
++#define __LINUX_MUTEX_RT_H
++
++#ifndef __LINUX_MUTEX_H
++#error "Please include mutex.h"
++#endif
++
++#include <linux/rtmutex.h>
++
++/* FIXME: Just for __lockfunc */
++#include <linux/spinlock.h>
++
++struct mutex {
++ struct rt_mutex lock;
++#ifdef CONFIG_DEBUG_LOCK_ALLOC
++ struct lockdep_map dep_map;
++#endif
++};
++
++#define __MUTEX_INITIALIZER(mutexname) \
++ { \
++ .lock = __RT_MUTEX_INITIALIZER(mutexname.lock) \
++ __DEP_MAP_MUTEX_INITIALIZER(mutexname) \
++ }
++
++#define DEFINE_MUTEX(mutexname) \
++ struct mutex mutexname = __MUTEX_INITIALIZER(mutexname)
++
++extern void __mutex_do_init(struct mutex *lock, const char *name, struct lock_class_key *key);
++extern void __lockfunc _mutex_lock(struct mutex *lock);
++extern int __lockfunc _mutex_lock_interruptible(struct mutex *lock);
++extern int __lockfunc _mutex_lock_killable(struct mutex *lock);
++extern void __lockfunc _mutex_lock_nested(struct mutex *lock, int subclass);
++extern void __lockfunc _mutex_lock_nest_lock(struct mutex *lock, struct lockdep_map *nest_lock);
++extern int __lockfunc _mutex_lock_interruptible_nested(struct mutex *lock, int subclass);
++extern int __lockfunc _mutex_lock_killable_nested(struct mutex *lock, int subclass);
++extern int __lockfunc _mutex_trylock(struct mutex *lock);
++extern void __lockfunc _mutex_unlock(struct mutex *lock);
++
++#define mutex_is_locked(l) rt_mutex_is_locked(&(l)->lock)
++#define mutex_lock(l) _mutex_lock(l)
++#define mutex_lock_interruptible(l) _mutex_lock_interruptible(l)
++#define mutex_lock_killable(l) _mutex_lock_killable(l)
++#define mutex_trylock(l) _mutex_trylock(l)
++#define mutex_unlock(l) _mutex_unlock(l)
++#define mutex_destroy(l) rt_mutex_destroy(&(l)->lock)
++
++#ifdef CONFIG_DEBUG_LOCK_ALLOC
++# define mutex_lock_nested(l, s) _mutex_lock_nested(l, s)
++# define mutex_lock_interruptible_nested(l, s) \
++ _mutex_lock_interruptible_nested(l, s)
++# define mutex_lock_killable_nested(l, s) \
++ _mutex_lock_killable_nested(l, s)
++
++# define mutex_lock_nest_lock(lock, nest_lock) \
++do { \
++ typecheck(struct lockdep_map *, &(nest_lock)->dep_map); \
++ _mutex_lock_nest_lock(lock, &(nest_lock)->dep_map); \
++} while (0)
++
++#else
++# define mutex_lock_nested(l, s) _mutex_lock(l)
++# define mutex_lock_interruptible_nested(l, s) \
++ _mutex_lock_interruptible(l)
++# define mutex_lock_killable_nested(l, s) \
++ _mutex_lock_killable(l)
++# define mutex_lock_nest_lock(lock, nest_lock) mutex_lock(lock)
++#endif
++
++# define mutex_init(mutex) \
++do { \
++ static struct lock_class_key __key; \
++ \
++ rt_mutex_init(&(mutex)->lock); \
++ __mutex_do_init((mutex), #mutex, &__key); \
++} while (0)
++
++# define __mutex_init(mutex, name, key) \
++do { \
++ rt_mutex_init(&(mutex)->lock); \
++ __mutex_do_init((mutex), name, key); \
++} while (0)
++
++#endif
+diff -Nur linux-4.8.15.orig/include/linux/netdevice.h linux-4.8.15/include/linux/netdevice.h
+--- linux-4.8.15.orig/include/linux/netdevice.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/netdevice.h 2017-01-01 17:07:15.807412535 +0100
+@@ -395,7 +395,19 @@
+ typedef rx_handler_result_t rx_handler_func_t(struct sk_buff **pskb);
+
+ void __napi_schedule(struct napi_struct *n);
++
++/*
++ * When PREEMPT_RT_FULL is defined, all device interrupt handlers
++ * run as threads, and they can also be preempted (without PREEMPT_RT
++ * interrupt threads can not be preempted). Which means that calling
++ * __napi_schedule_irqoff() from an interrupt handler can be preempted
++ * and can corrupt the napi->poll_list.
++ */
++#ifdef CONFIG_PREEMPT_RT_FULL
++#define __napi_schedule_irqoff(n) __napi_schedule(n)
++#else
+ void __napi_schedule_irqoff(struct napi_struct *n);
++#endif
+
+ static inline bool napi_disable_pending(struct napi_struct *n)
+ {
+@@ -2446,14 +2458,53 @@
+ void synchronize_net(void);
+ int init_dummy_netdev(struct net_device *dev);
+
+-DECLARE_PER_CPU(int, xmit_recursion);
+ #define XMIT_RECURSION_LIMIT 10
++#ifdef CONFIG_PREEMPT_RT_FULL
++static inline int dev_recursion_level(void)
++{
++ return current->xmit_recursion;
++}
++
++static inline int xmit_rec_read(void)
++{
++ return current->xmit_recursion;
++}
++
++static inline void xmit_rec_inc(void)
++{
++ current->xmit_recursion++;
++}
++
++static inline void xmit_rec_dec(void)
++{
++ current->xmit_recursion--;
++}
++
++#else
++
++DECLARE_PER_CPU(int, xmit_recursion);
+
+ static inline int dev_recursion_level(void)
+ {
+ return this_cpu_read(xmit_recursion);
+ }
+
++static inline int xmit_rec_read(void)
++{
++ return __this_cpu_read(xmit_recursion);
++}
++
++static inline void xmit_rec_inc(void)
++{
++ __this_cpu_inc(xmit_recursion);
++}
++
++static inline void xmit_rec_dec(void)
++{
++ __this_cpu_dec(xmit_recursion);
++}
++#endif
++
+ struct net_device *dev_get_by_index(struct net *net, int ifindex);
+ struct net_device *__dev_get_by_index(struct net *net, int ifindex);
+ struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex);
+@@ -2831,6 +2882,7 @@
+ unsigned int dropped;
+ struct sk_buff_head input_pkt_queue;
+ struct napi_struct backlog;
++ struct sk_buff_head tofree_queue;
+
+ };
+
+diff -Nur linux-4.8.15.orig/include/linux/netfilter/x_tables.h linux-4.8.15/include/linux/netfilter/x_tables.h
+--- linux-4.8.15.orig/include/linux/netfilter/x_tables.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/netfilter/x_tables.h 2017-01-01 17:07:15.815413044 +0100
+@@ -4,6 +4,7 @@
+
+ #include <linux/netdevice.h>
+ #include <linux/static_key.h>
++#include <linux/locallock.h>
+ #include <uapi/linux/netfilter/x_tables.h>
+
+ /* Test a struct->invflags and a boolean for inequality */
+@@ -300,6 +301,8 @@
+ */
+ DECLARE_PER_CPU(seqcount_t, xt_recseq);
+
++DECLARE_LOCAL_IRQ_LOCK(xt_write_lock);
++
+ /* xt_tee_enabled - true if x_tables needs to handle reentrancy
+ *
+ * Enabled if current ip(6)tables ruleset has at least one -j TEE rule.
+@@ -320,6 +323,9 @@
+ {
+ unsigned int addend;
+
++ /* RT protection */
++ local_lock(xt_write_lock);
++
+ /*
+ * Low order bit of sequence is set if we already
+ * called xt_write_recseq_begin().
+@@ -350,6 +356,7 @@
+ /* this is kind of a write_seqcount_end(), but addend is 0 or 1 */
+ smp_wmb();
+ __this_cpu_add(xt_recseq.sequence, addend);
++ local_unlock(xt_write_lock);
+ }
+
+ /*
+diff -Nur linux-4.8.15.orig/include/linux/nfs_fs.h linux-4.8.15/include/linux/nfs_fs.h
+--- linux-4.8.15.orig/include/linux/nfs_fs.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/nfs_fs.h 2017-01-01 17:07:15.815413044 +0100
+@@ -165,7 +165,11 @@
+
+ /* Readers: in-flight sillydelete RPC calls */
+ /* Writers: rmdir */
++#ifdef CONFIG_PREEMPT_RT_BASE
++ struct semaphore rmdir_sem;
++#else
+ struct rw_semaphore rmdir_sem;
++#endif
+
+ #if IS_ENABLED(CONFIG_NFS_V4)
+ struct nfs4_cached_acl *nfs4_acl;
+diff -Nur linux-4.8.15.orig/include/linux/nfs_xdr.h linux-4.8.15/include/linux/nfs_xdr.h
+--- linux-4.8.15.orig/include/linux/nfs_xdr.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/nfs_xdr.h 2017-01-01 17:07:15.831414081 +0100
+@@ -1484,7 +1484,7 @@
+ struct nfs_removeargs args;
+ struct nfs_removeres res;
+ struct dentry *dentry;
+- wait_queue_head_t wq;
++ struct swait_queue_head wq;
+ struct rpc_cred *cred;
+ struct nfs_fattr dir_attr;
+ long timeout;
+diff -Nur linux-4.8.15.orig/include/linux/notifier.h linux-4.8.15/include/linux/notifier.h
+--- linux-4.8.15.orig/include/linux/notifier.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/notifier.h 2017-01-01 17:07:15.831414081 +0100
+@@ -6,7 +6,7 @@
+ *
+ * Alan Cox <Alan.Cox@linux.org>
+ */
+-
++
+ #ifndef _LINUX_NOTIFIER_H
+ #define _LINUX_NOTIFIER_H
+ #include <linux/errno.h>
+@@ -42,9 +42,7 @@
+ * in srcu_notifier_call_chain(): no cache bounces and no memory barriers.
+ * As compensation, srcu_notifier_chain_unregister() is rather expensive.
+ * SRCU notifier chains should be used when the chain will be called very
+- * often but notifier_blocks will seldom be removed. Also, SRCU notifier
+- * chains are slightly more difficult to use because they require special
+- * runtime initialization.
++ * often but notifier_blocks will seldom be removed.
+ */
+
+ struct notifier_block;
+@@ -90,7 +88,7 @@
+ (name)->head = NULL; \
+ } while (0)
+
+-/* srcu_notifier_heads must be initialized and cleaned up dynamically */
++/* srcu_notifier_heads must be cleaned up dynamically */
+ extern void srcu_init_notifier_head(struct srcu_notifier_head *nh);
+ #define srcu_cleanup_notifier_head(name) \
+ cleanup_srcu_struct(&(name)->srcu);
+@@ -103,7 +101,13 @@
+ .head = NULL }
+ #define RAW_NOTIFIER_INIT(name) { \
+ .head = NULL }
+-/* srcu_notifier_heads cannot be initialized statically */
++
++#define SRCU_NOTIFIER_INIT(name, pcpu) \
++ { \
++ .mutex = __MUTEX_INITIALIZER(name.mutex), \
++ .head = NULL, \
++ .srcu = __SRCU_STRUCT_INIT(name.srcu, pcpu), \
++ }
+
+ #define ATOMIC_NOTIFIER_HEAD(name) \
+ struct atomic_notifier_head name = \
+@@ -115,6 +119,18 @@
+ struct raw_notifier_head name = \
+ RAW_NOTIFIER_INIT(name)
+
++#define _SRCU_NOTIFIER_HEAD(name, mod) \
++ static DEFINE_PER_CPU(struct srcu_struct_array, \
++ name##_head_srcu_array); \
++ mod struct srcu_notifier_head name = \
++ SRCU_NOTIFIER_INIT(name, name##_head_srcu_array)
++
++#define SRCU_NOTIFIER_HEAD(name) \
++ _SRCU_NOTIFIER_HEAD(name, )
++
++#define SRCU_NOTIFIER_HEAD_STATIC(name) \
++ _SRCU_NOTIFIER_HEAD(name, static)
++
+ #ifdef __KERNEL__
+
+ extern int atomic_notifier_chain_register(struct atomic_notifier_head *nh,
+@@ -184,12 +200,12 @@
+
+ /*
+ * Declared notifiers so far. I can imagine quite a few more chains
+- * over time (eg laptop power reset chains, reboot chain (to clean
++ * over time (eg laptop power reset chains, reboot chain (to clean
+ * device units up), device [un]mount chain, module load/unload chain,
+- * low memory chain, screenblank chain (for plug in modular screenblankers)
++ * low memory chain, screenblank chain (for plug in modular screenblankers)
+ * VC switch chains (for loadable kernel svgalib VC switch helpers) etc...
+ */
+-
++
+ /* CPU notfiers are defined in include/linux/cpu.h. */
+
+ /* netdevice notifiers are defined in include/linux/netdevice.h */
+diff -Nur linux-4.8.15.orig/include/linux/percpu.h linux-4.8.15/include/linux/percpu.h
+--- linux-4.8.15.orig/include/linux/percpu.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/percpu.h 2017-01-01 17:07:15.843414849 +0100
+@@ -18,6 +18,35 @@
+ #define PERCPU_MODULE_RESERVE 0
+ #endif
+
++#ifdef CONFIG_PREEMPT_RT_FULL
++
++#define get_local_var(var) (*({ \
++ migrate_disable(); \
++ this_cpu_ptr(&var); }))
++
++#define put_local_var(var) do { \
++ (void)&(var); \
++ migrate_enable(); \
++} while (0)
++
++# define get_local_ptr(var) ({ \
++ migrate_disable(); \
++ this_cpu_ptr(var); })
++
++# define put_local_ptr(var) do { \
++ (void)(var); \
++ migrate_enable(); \
++} while (0)
++
++#else
++
++#define get_local_var(var) get_cpu_var(var)
++#define put_local_var(var) put_cpu_var(var)
++#define get_local_ptr(var) get_cpu_ptr(var)
++#define put_local_ptr(var) put_cpu_ptr(var)
++
++#endif
++
+ /* minimum unit size, also is the maximum supported allocation size */
+ #define PCPU_MIN_UNIT_SIZE PFN_ALIGN(32 << 10)
+
+diff -Nur linux-4.8.15.orig/include/linux/pid.h linux-4.8.15/include/linux/pid.h
+--- linux-4.8.15.orig/include/linux/pid.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/pid.h 2017-01-01 17:07:15.843414849 +0100
+@@ -2,6 +2,7 @@
+ #define _LINUX_PID_H
+
+ #include <linux/rcupdate.h>
++#include <linux/atomic.h>
+
+ enum pid_type
+ {
+diff -Nur linux-4.8.15.orig/include/linux/preempt.h linux-4.8.15/include/linux/preempt.h
+--- linux-4.8.15.orig/include/linux/preempt.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/preempt.h 2017-01-01 17:07:15.851415364 +0100
+@@ -50,7 +50,11 @@
+ #define HARDIRQ_OFFSET (1UL << HARDIRQ_SHIFT)
+ #define NMI_OFFSET (1UL << NMI_SHIFT)
+
+-#define SOFTIRQ_DISABLE_OFFSET (2 * SOFTIRQ_OFFSET)
++#ifndef CONFIG_PREEMPT_RT_FULL
++# define SOFTIRQ_DISABLE_OFFSET (2 * SOFTIRQ_OFFSET)
++#else
++# define SOFTIRQ_DISABLE_OFFSET (0)
++#endif
+
+ /* We use the MSB mostly because its available */
+ #define PREEMPT_NEED_RESCHED 0x80000000
+@@ -59,9 +63,15 @@
+ #include <asm/preempt.h>
+
+ #define hardirq_count() (preempt_count() & HARDIRQ_MASK)
+-#define softirq_count() (preempt_count() & SOFTIRQ_MASK)
+ #define irq_count() (preempt_count() & (HARDIRQ_MASK | SOFTIRQ_MASK \
+ | NMI_MASK))
++#ifndef CONFIG_PREEMPT_RT_FULL
++# define softirq_count() (preempt_count() & SOFTIRQ_MASK)
++# define in_serving_softirq() (softirq_count() & SOFTIRQ_OFFSET)
++#else
++# define softirq_count() (0UL)
++extern int in_serving_softirq(void);
++#endif
+
+ /*
+ * Are we doing bottom half or hardware interrupt processing?
+@@ -72,7 +82,6 @@
+ #define in_irq() (hardirq_count())
+ #define in_softirq() (softirq_count())
+ #define in_interrupt() (irq_count())
+-#define in_serving_softirq() (softirq_count() & SOFTIRQ_OFFSET)
+
+ /*
+ * Are we in NMI context?
+@@ -91,7 +100,11 @@
+ /*
+ * The preempt_count offset after spin_lock()
+ */
++#if !defined(CONFIG_PREEMPT_RT_FULL)
+ #define PREEMPT_LOCK_OFFSET PREEMPT_DISABLE_OFFSET
++#else
++#define PREEMPT_LOCK_OFFSET 0
++#endif
+
+ /*
+ * The preempt_count offset needed for things like:
+@@ -140,6 +153,20 @@
+ #define preempt_count_inc() preempt_count_add(1)
+ #define preempt_count_dec() preempt_count_sub(1)
+
++#ifdef CONFIG_PREEMPT_LAZY
++#define add_preempt_lazy_count(val) do { preempt_lazy_count() += (val); } while (0)
++#define sub_preempt_lazy_count(val) do { preempt_lazy_count() -= (val); } while (0)
++#define inc_preempt_lazy_count() add_preempt_lazy_count(1)
++#define dec_preempt_lazy_count() sub_preempt_lazy_count(1)
++#define preempt_lazy_count() (current_thread_info()->preempt_lazy_count)
++#else
++#define add_preempt_lazy_count(val) do { } while (0)
++#define sub_preempt_lazy_count(val) do { } while (0)
++#define inc_preempt_lazy_count() do { } while (0)
++#define dec_preempt_lazy_count() do { } while (0)
++#define preempt_lazy_count() (0)
++#endif
++
+ #ifdef CONFIG_PREEMPT_COUNT
+
+ #define preempt_disable() \
+@@ -148,13 +175,25 @@
+ barrier(); \
+ } while (0)
+
++#define preempt_lazy_disable() \
++do { \
++ inc_preempt_lazy_count(); \
++ barrier(); \
++} while (0)
++
+ #define sched_preempt_enable_no_resched() \
+ do { \
+ barrier(); \
+ preempt_count_dec(); \
+ } while (0)
+
+-#define preempt_enable_no_resched() sched_preempt_enable_no_resched()
++#ifdef CONFIG_PREEMPT_RT_BASE
++# define preempt_enable_no_resched() sched_preempt_enable_no_resched()
++# define preempt_check_resched_rt() preempt_check_resched()
++#else
++# define preempt_enable_no_resched() preempt_enable()
++# define preempt_check_resched_rt() barrier();
++#endif
+
+ #define preemptible() (preempt_count() == 0 && !irqs_disabled())
+
+@@ -179,6 +218,13 @@
+ __preempt_schedule(); \
+ } while (0)
+
++#define preempt_lazy_enable() \
++do { \
++ dec_preempt_lazy_count(); \
++ barrier(); \
++ preempt_check_resched(); \
++} while (0)
++
+ #else /* !CONFIG_PREEMPT */
+ #define preempt_enable() \
+ do { \
+@@ -224,6 +270,7 @@
+ #define preempt_disable_notrace() barrier()
+ #define preempt_enable_no_resched_notrace() barrier()
+ #define preempt_enable_notrace() barrier()
++#define preempt_check_resched_rt() barrier()
+ #define preemptible() 0
+
+ #endif /* CONFIG_PREEMPT_COUNT */
+@@ -244,10 +291,31 @@
+ } while (0)
+ #define preempt_fold_need_resched() \
+ do { \
+- if (tif_need_resched()) \
++ if (tif_need_resched_now()) \
+ set_preempt_need_resched(); \
+ } while (0)
+
++#ifdef CONFIG_PREEMPT_RT_FULL
++# define preempt_disable_rt() preempt_disable()
++# define preempt_enable_rt() preempt_enable()
++# define preempt_disable_nort() barrier()
++# define preempt_enable_nort() barrier()
++# ifdef CONFIG_SMP
++ extern void migrate_disable(void);
++ extern void migrate_enable(void);
++# else /* CONFIG_SMP */
++# define migrate_disable() barrier()
++# define migrate_enable() barrier()
++# endif /* CONFIG_SMP */
++#else
++# define preempt_disable_rt() barrier()
++# define preempt_enable_rt() barrier()
++# define preempt_disable_nort() preempt_disable()
++# define preempt_enable_nort() preempt_enable()
++# define migrate_disable() preempt_disable()
++# define migrate_enable() preempt_enable()
++#endif
++
+ #ifdef CONFIG_PREEMPT_NOTIFIERS
+
+ struct preempt_notifier;
+diff -Nur linux-4.8.15.orig/include/linux/printk.h linux-4.8.15/include/linux/printk.h
+--- linux-4.8.15.orig/include/linux/printk.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/printk.h 2017-01-01 17:07:15.855415618 +0100
+@@ -125,9 +125,11 @@
+ #ifdef CONFIG_EARLY_PRINTK
+ extern asmlinkage __printf(1, 2)
+ void early_printk(const char *fmt, ...);
++extern void printk_kill(void);
+ #else
+ static inline __printf(1, 2) __cold
+ void early_printk(const char *s, ...) { }
++static inline void printk_kill(void) { }
+ #endif
+
+ #ifdef CONFIG_PRINTK_NMI
+diff -Nur linux-4.8.15.orig/include/linux/radix-tree.h linux-4.8.15/include/linux/radix-tree.h
+--- linux-4.8.15.orig/include/linux/radix-tree.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/radix-tree.h 2017-01-01 17:07:15.859415876 +0100
+@@ -289,9 +289,19 @@
+ unsigned int radix_tree_gang_lookup_slot(struct radix_tree_root *root,
+ void ***results, unsigned long *indices,
+ unsigned long first_index, unsigned int max_items);
++#ifdef CONFIG_PREEMPT_RT_FULL
++static inline int radix_tree_preload(gfp_t gm) { return 0; }
++static inline int radix_tree_maybe_preload(gfp_t gfp_mask) { return 0; }
++static inline int radix_tree_maybe_preload_order(gfp_t gfp_mask, int order)
++{
++ return 0;
++};
++
++#else
+ int radix_tree_preload(gfp_t gfp_mask);
+ int radix_tree_maybe_preload(gfp_t gfp_mask);
+ int radix_tree_maybe_preload_order(gfp_t gfp_mask, int order);
++#endif
+ void radix_tree_init(void);
+ void *radix_tree_tag_set(struct radix_tree_root *root,
+ unsigned long index, unsigned int tag);
+@@ -316,7 +326,7 @@
+
+ static inline void radix_tree_preload_end(void)
+ {
+- preempt_enable();
++ preempt_enable_nort();
+ }
+
+ /**
+diff -Nur linux-4.8.15.orig/include/linux/random.h linux-4.8.15/include/linux/random.h
+--- linux-4.8.15.orig/include/linux/random.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/random.h 2017-01-01 17:07:15.859415876 +0100
+@@ -20,7 +20,7 @@
+ extern void add_device_randomness(const void *, unsigned int);
+ extern void add_input_randomness(unsigned int type, unsigned int code,
+ unsigned int value);
+-extern void add_interrupt_randomness(int irq, int irq_flags);
++extern void add_interrupt_randomness(int irq, int irq_flags, __u64 ip);
+
+ extern void get_random_bytes(void *buf, int nbytes);
+ extern int add_random_ready_callback(struct random_ready_callback *rdy);
+diff -Nur linux-4.8.15.orig/include/linux/rbtree_augmented.h linux-4.8.15/include/linux/rbtree_augmented.h
+--- linux-4.8.15.orig/include/linux/rbtree_augmented.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/rbtree_augmented.h 2017-01-01 17:07:15.859415876 +0100
+@@ -26,6 +26,7 @@
+
+ #include <linux/compiler.h>
+ #include <linux/rbtree.h>
++#include <linux/rcupdate.h>
+
+ /*
+ * Please note - only struct rb_augment_callbacks and the prototypes for
+diff -Nur linux-4.8.15.orig/include/linux/rbtree.h linux-4.8.15/include/linux/rbtree.h
+--- linux-4.8.15.orig/include/linux/rbtree.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/rbtree.h 2017-01-01 17:07:15.859415876 +0100
+@@ -31,7 +31,7 @@
+
+ #include <linux/kernel.h>
+ #include <linux/stddef.h>
+-#include <linux/rcupdate.h>
++#include <linux/rcu_assign_pointer.h>
+
+ struct rb_node {
+ unsigned long __rb_parent_color;
+diff -Nur linux-4.8.15.orig/include/linux/rcu_assign_pointer.h linux-4.8.15/include/linux/rcu_assign_pointer.h
+--- linux-4.8.15.orig/include/linux/rcu_assign_pointer.h 1970-01-01 01:00:00.000000000 +0100
++++ linux-4.8.15/include/linux/rcu_assign_pointer.h 2017-01-01 17:07:15.859415876 +0100
+@@ -0,0 +1,54 @@
++#ifndef __LINUX_RCU_ASSIGN_POINTER_H__
++#define __LINUX_RCU_ASSIGN_POINTER_H__
++#include <linux/compiler.h>
++#include <asm/barrier.h>
++
++/**
++ * RCU_INITIALIZER() - statically initialize an RCU-protected global variable
++ * @v: The value to statically initialize with.
++ */
++#define RCU_INITIALIZER(v) (typeof(*(v)) __force __rcu *)(v)
++
++/**
++ * rcu_assign_pointer() - assign to RCU-protected pointer
++ * @p: pointer to assign to
++ * @v: value to assign (publish)
++ *
++ * Assigns the specified value to the specified RCU-protected
++ * pointer, ensuring that any concurrent RCU readers will see
++ * any prior initialization.
++ *
++ * Inserts memory barriers on architectures that require them
++ * (which is most of them), and also prevents the compiler from
++ * reordering the code that initializes the structure after the pointer
++ * assignment. More importantly, this call documents which pointers
++ * will be dereferenced by RCU read-side code.
++ *
++ * In some special cases, you may use RCU_INIT_POINTER() instead
++ * of rcu_assign_pointer(). RCU_INIT_POINTER() is a bit faster due
++ * to the fact that it does not constrain either the CPU or the compiler.
++ * That said, using RCU_INIT_POINTER() when you should have used
++ * rcu_assign_pointer() is a very bad thing that results in
++ * impossible-to-diagnose memory corruption. So please be careful.
++ * See the RCU_INIT_POINTER() comment header for details.
++ *
++ * Note that rcu_assign_pointer() evaluates each of its arguments only
++ * once, appearances notwithstanding. One of the "extra" evaluations
++ * is in typeof() and the other visible only to sparse (__CHECKER__),
++ * neither of which actually execute the argument. As with most cpp
++ * macros, this execute-arguments-only-once property is important, so
++ * please be careful when making changes to rcu_assign_pointer() and the
++ * other macros that it invokes.
++ */
++#define rcu_assign_pointer(p, v) \
++({ \
++ uintptr_t _r_a_p__v = (uintptr_t)(v); \
++ \
++ if (__builtin_constant_p(v) && (_r_a_p__v) == (uintptr_t)NULL) \
++ WRITE_ONCE((p), (typeof(p))(_r_a_p__v)); \
++ else \
++ smp_store_release(&p, RCU_INITIALIZER((typeof(p))_r_a_p__v)); \
++ _r_a_p__v; \
++})
++
++#endif
+diff -Nur linux-4.8.15.orig/include/linux/rcupdate.h linux-4.8.15/include/linux/rcupdate.h
+--- linux-4.8.15.orig/include/linux/rcupdate.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/rcupdate.h 2017-01-01 17:07:15.867416395 +0100
+@@ -46,6 +46,7 @@
+ #include <linux/compiler.h>
+ #include <linux/ktime.h>
+ #include <linux/irqflags.h>
++#include <linux/rcu_assign_pointer.h>
+
+ #include <asm/barrier.h>
+
+@@ -178,6 +179,9 @@
+
+ #endif /* #else #ifdef CONFIG_PREEMPT_RCU */
+
++#ifdef CONFIG_PREEMPT_RT_FULL
++#define call_rcu_bh call_rcu
++#else
+ /**
+ * call_rcu_bh() - Queue an RCU for invocation after a quicker grace period.
+ * @head: structure to be used for queueing the RCU updates.
+@@ -201,6 +205,7 @@
+ */
+ void call_rcu_bh(struct rcu_head *head,
+ rcu_callback_t func);
++#endif
+
+ /**
+ * call_rcu_sched() - Queue an RCU for invocation after sched grace period.
+@@ -301,6 +306,11 @@
+ * types of kernel builds, the rcu_read_lock() nesting depth is unknowable.
+ */
+ #define rcu_preempt_depth() (current->rcu_read_lock_nesting)
++#ifndef CONFIG_PREEMPT_RT_FULL
++#define sched_rcu_preempt_depth() rcu_preempt_depth()
++#else
++static inline int sched_rcu_preempt_depth(void) { return 0; }
++#endif
+
+ #else /* #ifdef CONFIG_PREEMPT_RCU */
+
+@@ -326,6 +336,8 @@
+ return 0;
+ }
+
++#define sched_rcu_preempt_depth() rcu_preempt_depth()
++
+ #endif /* #else #ifdef CONFIG_PREEMPT_RCU */
+
+ /* Internal to kernel */
+@@ -500,7 +512,14 @@
+ int debug_lockdep_rcu_enabled(void);
+
+ int rcu_read_lock_held(void);
++#ifdef CONFIG_PREEMPT_RT_FULL
++static inline int rcu_read_lock_bh_held(void)
++{
++ return rcu_read_lock_held();
++}
++#else
+ int rcu_read_lock_bh_held(void);
++#endif
+
+ /**
+ * rcu_read_lock_sched_held() - might we be in RCU-sched read-side critical section?
+@@ -621,54 +640,6 @@
+ })
+
+ /**
+- * RCU_INITIALIZER() - statically initialize an RCU-protected global variable
+- * @v: The value to statically initialize with.
+- */
+-#define RCU_INITIALIZER(v) (typeof(*(v)) __force __rcu *)(v)
+-
+-/**
+- * rcu_assign_pointer() - assign to RCU-protected pointer
+- * @p: pointer to assign to
+- * @v: value to assign (publish)
+- *
+- * Assigns the specified value to the specified RCU-protected
+- * pointer, ensuring that any concurrent RCU readers will see
+- * any prior initialization.
+- *
+- * Inserts memory barriers on architectures that require them
+- * (which is most of them), and also prevents the compiler from
+- * reordering the code that initializes the structure after the pointer
+- * assignment. More importantly, this call documents which pointers
+- * will be dereferenced by RCU read-side code.
+- *
+- * In some special cases, you may use RCU_INIT_POINTER() instead
+- * of rcu_assign_pointer(). RCU_INIT_POINTER() is a bit faster due
+- * to the fact that it does not constrain either the CPU or the compiler.
+- * That said, using RCU_INIT_POINTER() when you should have used
+- * rcu_assign_pointer() is a very bad thing that results in
+- * impossible-to-diagnose memory corruption. So please be careful.
+- * See the RCU_INIT_POINTER() comment header for details.
+- *
+- * Note that rcu_assign_pointer() evaluates each of its arguments only
+- * once, appearances notwithstanding. One of the "extra" evaluations
+- * is in typeof() and the other visible only to sparse (__CHECKER__),
+- * neither of which actually execute the argument. As with most cpp
+- * macros, this execute-arguments-only-once property is important, so
+- * please be careful when making changes to rcu_assign_pointer() and the
+- * other macros that it invokes.
+- */
+-#define rcu_assign_pointer(p, v) \
+-({ \
+- uintptr_t _r_a_p__v = (uintptr_t)(v); \
+- \
+- if (__builtin_constant_p(v) && (_r_a_p__v) == (uintptr_t)NULL) \
+- WRITE_ONCE((p), (typeof(p))(_r_a_p__v)); \
+- else \
+- smp_store_release(&p, RCU_INITIALIZER((typeof(p))_r_a_p__v)); \
+- _r_a_p__v; \
+-})
+-
+-/**
+ * rcu_access_pointer() - fetch RCU pointer with no dereferencing
+ * @p: The pointer to read
+ *
+@@ -946,10 +917,14 @@
+ static inline void rcu_read_lock_bh(void)
+ {
+ local_bh_disable();
++#ifdef CONFIG_PREEMPT_RT_FULL
++ rcu_read_lock();
++#else
+ __acquire(RCU_BH);
+ rcu_lock_acquire(&rcu_bh_lock_map);
+ RCU_LOCKDEP_WARN(!rcu_is_watching(),
+ "rcu_read_lock_bh() used illegally while idle");
++#endif
+ }
+
+ /*
+@@ -959,10 +934,14 @@
+ */
+ static inline void rcu_read_unlock_bh(void)
+ {
++#ifdef CONFIG_PREEMPT_RT_FULL
++ rcu_read_unlock();
++#else
+ RCU_LOCKDEP_WARN(!rcu_is_watching(),
+ "rcu_read_unlock_bh() used illegally while idle");
+ rcu_lock_release(&rcu_bh_lock_map);
+ __release(RCU_BH);
++#endif
+ local_bh_enable();
+ }
+
+diff -Nur linux-4.8.15.orig/include/linux/rcutree.h linux-4.8.15/include/linux/rcutree.h
+--- linux-4.8.15.orig/include/linux/rcutree.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/rcutree.h 2017-01-01 17:07:15.867416395 +0100
+@@ -44,7 +44,11 @@
+ rcu_note_context_switch();
+ }
+
++#ifdef CONFIG_PREEMPT_RT_FULL
++# define synchronize_rcu_bh synchronize_rcu
++#else
+ void synchronize_rcu_bh(void);
++#endif
+ void synchronize_sched_expedited(void);
+ void synchronize_rcu_expedited(void);
+
+@@ -72,7 +76,11 @@
+ }
+
+ void rcu_barrier(void);
++#ifdef CONFIG_PREEMPT_RT_FULL
++# define rcu_barrier_bh rcu_barrier
++#else
+ void rcu_barrier_bh(void);
++#endif
+ void rcu_barrier_sched(void);
+ unsigned long get_state_synchronize_rcu(void);
+ void cond_synchronize_rcu(unsigned long oldstate);
+@@ -82,17 +90,14 @@
+ extern unsigned long rcutorture_testseq;
+ extern unsigned long rcutorture_vernum;
+ unsigned long rcu_batches_started(void);
+-unsigned long rcu_batches_started_bh(void);
+ unsigned long rcu_batches_started_sched(void);
+ unsigned long rcu_batches_completed(void);
+-unsigned long rcu_batches_completed_bh(void);
+ unsigned long rcu_batches_completed_sched(void);
+ unsigned long rcu_exp_batches_completed(void);
+ unsigned long rcu_exp_batches_completed_sched(void);
+ void show_rcu_gp_kthreads(void);
+
+ void rcu_force_quiescent_state(void);
+-void rcu_bh_force_quiescent_state(void);
+ void rcu_sched_force_quiescent_state(void);
+
+ void rcu_idle_enter(void);
+@@ -109,6 +114,16 @@
+
+ bool rcu_is_watching(void);
+
++#ifndef CONFIG_PREEMPT_RT_FULL
++void rcu_bh_force_quiescent_state(void);
++unsigned long rcu_batches_started_bh(void);
++unsigned long rcu_batches_completed_bh(void);
++#else
++# define rcu_bh_force_quiescent_state rcu_force_quiescent_state
++# define rcu_batches_completed_bh rcu_batches_completed
++# define rcu_batches_started_bh rcu_batches_completed
++#endif
++
+ void rcu_all_qs(void);
+
+ /* RCUtree hotplug events */
+diff -Nur linux-4.8.15.orig/include/linux/rtmutex.h linux-4.8.15/include/linux/rtmutex.h
+--- linux-4.8.15.orig/include/linux/rtmutex.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/rtmutex.h 2017-01-01 17:07:15.875416916 +0100
+@@ -13,11 +13,15 @@
+ #define __LINUX_RT_MUTEX_H
+
+ #include <linux/linkage.h>
++#include <linux/spinlock_types_raw.h>
+ #include <linux/rbtree.h>
+-#include <linux/spinlock_types.h>
+
+ extern int max_lock_depth; /* for sysctl */
+
++#ifdef CONFIG_DEBUG_MUTEXES
++#include <linux/debug_locks.h>
++#endif
++
+ /**
+ * The rt_mutex structure
+ *
+@@ -31,8 +35,8 @@
+ struct rb_root waiters;
+ struct rb_node *waiters_leftmost;
+ struct task_struct *owner;
+-#ifdef CONFIG_DEBUG_RT_MUTEXES
+ int save_state;
++#ifdef CONFIG_DEBUG_RT_MUTEXES
+ const char *name, *file;
+ int line;
+ void *magic;
+@@ -55,22 +59,33 @@
+ # define rt_mutex_debug_check_no_locks_held(task) do { } while (0)
+ #endif
+
++# define rt_mutex_init(mutex) \
++ do { \
++ raw_spin_lock_init(&(mutex)->wait_lock); \
++ __rt_mutex_init(mutex, #mutex); \
++ } while (0)
++
+ #ifdef CONFIG_DEBUG_RT_MUTEXES
+ # define __DEBUG_RT_MUTEX_INITIALIZER(mutexname) \
+ , .name = #mutexname, .file = __FILE__, .line = __LINE__
+-# define rt_mutex_init(mutex) __rt_mutex_init(mutex, __func__)
+ extern void rt_mutex_debug_task_free(struct task_struct *tsk);
+ #else
+ # define __DEBUG_RT_MUTEX_INITIALIZER(mutexname)
+-# define rt_mutex_init(mutex) __rt_mutex_init(mutex, NULL)
+ # define rt_mutex_debug_task_free(t) do { } while (0)
+ #endif
+
+-#define __RT_MUTEX_INITIALIZER(mutexname) \
+- { .wait_lock = __RAW_SPIN_LOCK_UNLOCKED(mutexname.wait_lock) \
++#define __RT_MUTEX_INITIALIZER_PLAIN(mutexname) \
++ .wait_lock = __RAW_SPIN_LOCK_UNLOCKED(mutexname.wait_lock) \
+ , .waiters = RB_ROOT \
+ , .owner = NULL \
+- __DEBUG_RT_MUTEX_INITIALIZER(mutexname)}
++ __DEBUG_RT_MUTEX_INITIALIZER(mutexname)
++
++#define __RT_MUTEX_INITIALIZER(mutexname) \
++ { __RT_MUTEX_INITIALIZER_PLAIN(mutexname) }
++
++#define __RT_MUTEX_INITIALIZER_SAVE_STATE(mutexname) \
++ { __RT_MUTEX_INITIALIZER_PLAIN(mutexname) \
++ , .save_state = 1 }
+
+ #define DEFINE_RT_MUTEX(mutexname) \
+ struct rt_mutex mutexname = __RT_MUTEX_INITIALIZER(mutexname)
+@@ -91,6 +106,7 @@
+
+ extern void rt_mutex_lock(struct rt_mutex *lock);
+ extern int rt_mutex_lock_interruptible(struct rt_mutex *lock);
++extern int rt_mutex_lock_killable(struct rt_mutex *lock);
+ extern int rt_mutex_timed_lock(struct rt_mutex *lock,
+ struct hrtimer_sleeper *timeout);
+
+diff -Nur linux-4.8.15.orig/include/linux/rwlock_rt.h linux-4.8.15/include/linux/rwlock_rt.h
+--- linux-4.8.15.orig/include/linux/rwlock_rt.h 1970-01-01 01:00:00.000000000 +0100
++++ linux-4.8.15/include/linux/rwlock_rt.h 2017-01-01 17:07:15.875416916 +0100
+@@ -0,0 +1,99 @@
++#ifndef __LINUX_RWLOCK_RT_H
++#define __LINUX_RWLOCK_RT_H
++
++#ifndef __LINUX_SPINLOCK_H
++#error Do not include directly. Use spinlock.h
++#endif
++
++#define rwlock_init(rwl) \
++do { \
++ static struct lock_class_key __key; \
++ \
++ rt_mutex_init(&(rwl)->lock); \
++ __rt_rwlock_init(rwl, #rwl, &__key); \
++} while (0)
++
++extern void __lockfunc rt_write_lock(rwlock_t *rwlock);
++extern void __lockfunc rt_read_lock(rwlock_t *rwlock);
++extern int __lockfunc rt_write_trylock(rwlock_t *rwlock);
++extern int __lockfunc rt_write_trylock_irqsave(rwlock_t *trylock, unsigned long *flags);
++extern int __lockfunc rt_read_trylock(rwlock_t *rwlock);
++extern void __lockfunc rt_write_unlock(rwlock_t *rwlock);
++extern void __lockfunc rt_read_unlock(rwlock_t *rwlock);
++extern unsigned long __lockfunc rt_write_lock_irqsave(rwlock_t *rwlock);
++extern unsigned long __lockfunc rt_read_lock_irqsave(rwlock_t *rwlock);
++extern void __rt_rwlock_init(rwlock_t *rwlock, char *name, struct lock_class_key *key);
++
++#define read_trylock(lock) __cond_lock(lock, rt_read_trylock(lock))
++#define write_trylock(lock) __cond_lock(lock, rt_write_trylock(lock))
++
++#define write_trylock_irqsave(lock, flags) \
++ __cond_lock(lock, rt_write_trylock_irqsave(lock, &flags))
++
++#define read_lock_irqsave(lock, flags) \
++ do { \
++ typecheck(unsigned long, flags); \
++ flags = rt_read_lock_irqsave(lock); \
++ } while (0)
++
++#define write_lock_irqsave(lock, flags) \
++ do { \
++ typecheck(unsigned long, flags); \
++ flags = rt_write_lock_irqsave(lock); \
++ } while (0)
++
++#define read_lock(lock) rt_read_lock(lock)
++
++#define read_lock_bh(lock) \
++ do { \
++ local_bh_disable(); \
++ rt_read_lock(lock); \
++ } while (0)
++
++#define read_lock_irq(lock) read_lock(lock)
++
++#define write_lock(lock) rt_write_lock(lock)
++
++#define write_lock_bh(lock) \
++ do { \
++ local_bh_disable(); \
++ rt_write_lock(lock); \
++ } while (0)
++
++#define write_lock_irq(lock) write_lock(lock)
++
++#define read_unlock(lock) rt_read_unlock(lock)
++
++#define read_unlock_bh(lock) \
++ do { \
++ rt_read_unlock(lock); \
++ local_bh_enable(); \
++ } while (0)
++
++#define read_unlock_irq(lock) read_unlock(lock)
++
++#define write_unlock(lock) rt_write_unlock(lock)
++
++#define write_unlock_bh(lock) \
++ do { \
++ rt_write_unlock(lock); \
++ local_bh_enable(); \
++ } while (0)
++
++#define write_unlock_irq(lock) write_unlock(lock)
++
++#define read_unlock_irqrestore(lock, flags) \
++ do { \
++ typecheck(unsigned long, flags); \
++ (void) flags; \
++ rt_read_unlock(lock); \
++ } while (0)
++
++#define write_unlock_irqrestore(lock, flags) \
++ do { \
++ typecheck(unsigned long, flags); \
++ (void) flags; \
++ rt_write_unlock(lock); \
++ } while (0)
++
++#endif
+diff -Nur linux-4.8.15.orig/include/linux/rwlock_types.h linux-4.8.15/include/linux/rwlock_types.h
+--- linux-4.8.15.orig/include/linux/rwlock_types.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/rwlock_types.h 2017-01-01 17:07:15.875416916 +0100
+@@ -1,6 +1,10 @@
+ #ifndef __LINUX_RWLOCK_TYPES_H
+ #define __LINUX_RWLOCK_TYPES_H
+
++#if !defined(__LINUX_SPINLOCK_TYPES_H)
++# error "Do not include directly, include spinlock_types.h"
++#endif
++
+ /*
+ * include/linux/rwlock_types.h - generic rwlock type definitions
+ * and initializers
+diff -Nur linux-4.8.15.orig/include/linux/rwlock_types_rt.h linux-4.8.15/include/linux/rwlock_types_rt.h
+--- linux-4.8.15.orig/include/linux/rwlock_types_rt.h 1970-01-01 01:00:00.000000000 +0100
++++ linux-4.8.15/include/linux/rwlock_types_rt.h 2017-01-01 17:07:15.875416916 +0100
+@@ -0,0 +1,33 @@
++#ifndef __LINUX_RWLOCK_TYPES_RT_H
++#define __LINUX_RWLOCK_TYPES_RT_H
++
++#ifndef __LINUX_SPINLOCK_TYPES_H
++#error "Do not include directly. Include spinlock_types.h instead"
++#endif
++
++/*
++ * rwlocks - rtmutex which allows single reader recursion
++ */
++typedef struct {
++ struct rt_mutex lock;
++ int read_depth;
++ unsigned int break_lock;
++#ifdef CONFIG_DEBUG_LOCK_ALLOC
++ struct lockdep_map dep_map;
++#endif
++} rwlock_t;
++
++#ifdef CONFIG_DEBUG_LOCK_ALLOC
++# define RW_DEP_MAP_INIT(lockname) .dep_map = { .name = #lockname }
++#else
++# define RW_DEP_MAP_INIT(lockname)
++#endif
++
++#define __RW_LOCK_UNLOCKED(name) \
++ { .lock = __RT_MUTEX_INITIALIZER_SAVE_STATE(name.lock), \
++ RW_DEP_MAP_INIT(name) }
++
++#define DEFINE_RWLOCK(name) \
++ rwlock_t name = __RW_LOCK_UNLOCKED(name)
++
++#endif
+diff -Nur linux-4.8.15.orig/include/linux/rwsem.h linux-4.8.15/include/linux/rwsem.h
+--- linux-4.8.15.orig/include/linux/rwsem.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/rwsem.h 2017-01-01 17:07:15.875416916 +0100
+@@ -19,6 +19,10 @@
+ #include <linux/osq_lock.h>
+ #endif
+
++#ifdef CONFIG_PREEMPT_RT_FULL
++#include <linux/rwsem_rt.h>
++#else /* PREEMPT_RT_FULL */
++
+ struct rw_semaphore;
+
+ #ifdef CONFIG_RWSEM_GENERIC_SPINLOCK
+@@ -184,4 +188,6 @@
+ # define up_read_non_owner(sem) up_read(sem)
+ #endif
+
++#endif /* !PREEMPT_RT_FULL */
++
+ #endif /* _LINUX_RWSEM_H */
+diff -Nur linux-4.8.15.orig/include/linux/rwsem_rt.h linux-4.8.15/include/linux/rwsem_rt.h
+--- linux-4.8.15.orig/include/linux/rwsem_rt.h 1970-01-01 01:00:00.000000000 +0100
++++ linux-4.8.15/include/linux/rwsem_rt.h 2017-01-01 17:07:15.875416916 +0100
+@@ -0,0 +1,167 @@
++#ifndef _LINUX_RWSEM_RT_H
++#define _LINUX_RWSEM_RT_H
++
++#ifndef _LINUX_RWSEM_H
++#error "Include rwsem.h"
++#endif
++
++/*
++ * RW-semaphores are a spinlock plus a reader-depth count.
++ *
++ * Note that the semantics are different from the usual
++ * Linux rw-sems, in PREEMPT_RT mode we do not allow
++ * multiple readers to hold the lock at once, we only allow
++ * a read-lock owner to read-lock recursively. This is
++ * better for latency, makes the implementation inherently
++ * fair and makes it simpler as well.
++ */
++
++#include <linux/rtmutex.h>
++
++struct rw_semaphore {
++ struct rt_mutex lock;
++ int read_depth;
++#ifdef CONFIG_DEBUG_LOCK_ALLOC
++ struct lockdep_map dep_map;
++#endif
++};
++
++#define __RWSEM_INITIALIZER(name) \
++ { .lock = __RT_MUTEX_INITIALIZER(name.lock), \
++ RW_DEP_MAP_INIT(name) }
++
++#define DECLARE_RWSEM(lockname) \
++ struct rw_semaphore lockname = __RWSEM_INITIALIZER(lockname)
++
++extern void __rt_rwsem_init(struct rw_semaphore *rwsem, const char *name,
++ struct lock_class_key *key);
++
++#define __rt_init_rwsem(sem, name, key) \
++ do { \
++ rt_mutex_init(&(sem)->lock); \
++ __rt_rwsem_init((sem), (name), (key));\
++ } while (0)
++
++#define __init_rwsem(sem, name, key) __rt_init_rwsem(sem, name, key)
++
++# define rt_init_rwsem(sem) \
++do { \
++ static struct lock_class_key __key; \
++ \
++ __rt_init_rwsem((sem), #sem, &__key); \
++} while (0)
++
++extern void rt_down_write(struct rw_semaphore *rwsem);
++extern int rt_down_write_killable(struct rw_semaphore *rwsem);
++extern void rt_down_read_nested(struct rw_semaphore *rwsem, int subclass);
++extern void rt_down_write_nested(struct rw_semaphore *rwsem, int subclass);
++extern int rt_down_write_killable_nested(struct rw_semaphore *rwsem,
++ int subclass);
++extern void rt_down_write_nested_lock(struct rw_semaphore *rwsem,
++ struct lockdep_map *nest);
++extern void rt__down_read(struct rw_semaphore *rwsem);
++extern void rt_down_read(struct rw_semaphore *rwsem);
++extern int rt_down_write_trylock(struct rw_semaphore *rwsem);
++extern int rt__down_read_trylock(struct rw_semaphore *rwsem);
++extern int rt_down_read_trylock(struct rw_semaphore *rwsem);
++extern void __rt_up_read(struct rw_semaphore *rwsem);
++extern void rt_up_read(struct rw_semaphore *rwsem);
++extern void rt_up_write(struct rw_semaphore *rwsem);
++extern void rt_downgrade_write(struct rw_semaphore *rwsem);
++
++#define init_rwsem(sem) rt_init_rwsem(sem)
++#define rwsem_is_locked(s) rt_mutex_is_locked(&(s)->lock)
++
++static inline int rwsem_is_contended(struct rw_semaphore *sem)
++{
++ /* rt_mutex_has_waiters() */
++ return !RB_EMPTY_ROOT(&sem->lock.waiters);
++}
++
++static inline void __down_read(struct rw_semaphore *sem)
++{
++ rt__down_read(sem);
++}
++
++static inline void down_read(struct rw_semaphore *sem)
++{
++ rt_down_read(sem);
++}
++
++static inline int __down_read_trylock(struct rw_semaphore *sem)
++{
++ return rt__down_read_trylock(sem);
++}
++
++static inline int down_read_trylock(struct rw_semaphore *sem)
++{
++ return rt_down_read_trylock(sem);
++}
++
++static inline void down_write(struct rw_semaphore *sem)
++{
++ rt_down_write(sem);
++}
++
++static inline int down_write_killable(struct rw_semaphore *sem)
++{
++ return rt_down_write_killable(sem);
++}
++
++static inline int down_write_trylock(struct rw_semaphore *sem)
++{
++ return rt_down_write_trylock(sem);
++}
++
++static inline void __up_read(struct rw_semaphore *sem)
++{
++ __rt_up_read(sem);
++}
++
++static inline void up_read(struct rw_semaphore *sem)
++{
++ rt_up_read(sem);
++}
++
++static inline void up_write(struct rw_semaphore *sem)
++{
++ rt_up_write(sem);
++}
++
++static inline void downgrade_write(struct rw_semaphore *sem)
++{
++ rt_downgrade_write(sem);
++}
++
++static inline void down_read_nested(struct rw_semaphore *sem, int subclass)
++{
++ return rt_down_read_nested(sem, subclass);
++}
++
++static inline void down_write_nested(struct rw_semaphore *sem, int subclass)
++{
++ rt_down_write_nested(sem, subclass);
++}
++
++static inline int down_write_killable_nested(struct rw_semaphore *sem,
++ int subclass)
++{
++ return rt_down_write_killable_nested(sem, subclass);
++}
++
++#ifdef CONFIG_DEBUG_LOCK_ALLOC
++static inline void down_write_nest_lock(struct rw_semaphore *sem,
++ struct rw_semaphore *nest_lock)
++{
++ rt_down_write_nested_lock(sem, &nest_lock->dep_map);
++}
++
++#else
++
++static inline void down_write_nest_lock(struct rw_semaphore *sem,
++ struct rw_semaphore *nest_lock)
++{
++ rt_down_write_nested_lock(sem, NULL);
++}
++#endif
++#endif
+diff -Nur linux-4.8.15.orig/include/linux/sched.h linux-4.8.15/include/linux/sched.h
+--- linux-4.8.15.orig/include/linux/sched.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/sched.h 2017-01-01 17:07:15.887417685 +0100
+@@ -26,6 +26,7 @@
+ #include <linux/nodemask.h>
+ #include <linux/mm_types.h>
+ #include <linux/preempt.h>
++#include <asm/kmap_types.h>
+
+ #include <asm/page.h>
+ #include <asm/ptrace.h>
+@@ -243,10 +244,7 @@
+ TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
+ __TASK_TRACED | EXIT_ZOMBIE | EXIT_DEAD)
+
+-#define task_is_traced(task) ((task->state & __TASK_TRACED) != 0)
+ #define task_is_stopped(task) ((task->state & __TASK_STOPPED) != 0)
+-#define task_is_stopped_or_traced(task) \
+- ((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0)
+ #define task_contributes_to_load(task) \
+ ((task->state & TASK_UNINTERRUPTIBLE) != 0 && \
+ (task->flags & PF_FROZEN) == 0 && \
+@@ -312,6 +310,11 @@
+
+ #endif
+
++#define __set_current_state_no_track(state_value) \
++ do { current->state = (state_value); } while (0)
++#define set_current_state_no_track(state_value) \
++ set_mb(current->state, (state_value))
++
+ /* Task command name length */
+ #define TASK_COMM_LEN 16
+
+@@ -1009,8 +1012,18 @@
+ struct wake_q_head name = { WAKE_Q_TAIL, &name.first }
+
+ extern void wake_q_add(struct wake_q_head *head,
+- struct task_struct *task);
+-extern void wake_up_q(struct wake_q_head *head);
++ struct task_struct *task);
++extern void __wake_up_q(struct wake_q_head *head, bool sleeper);
++
++static inline void wake_up_q(struct wake_q_head *head)
++{
++ __wake_up_q(head, false);
++}
++
++static inline void wake_up_q_sleeper(struct wake_q_head *head)
++{
++ __wake_up_q(head, true);
++}
+
+ /*
+ * sched-domains (multiprocessor balancing) declarations:
+@@ -1459,6 +1472,7 @@
+
+ struct task_struct {
+ volatile long state; /* -1 unrunnable, 0 runnable, >0 stopped */
++ volatile long saved_state; /* saved state for "spinlock sleepers" */
+ void *stack;
+ atomic_t usage;
+ unsigned int flags; /* per process flags, defined below */
+@@ -1495,6 +1509,12 @@
+ #endif
+
+ unsigned int policy;
++#ifdef CONFIG_PREEMPT_RT_FULL
++ int migrate_disable;
++# ifdef CONFIG_SCHED_DEBUG
++ int migrate_disable_atomic;
++# endif
++#endif
+ int nr_cpus_allowed;
+ cpumask_t cpus_allowed;
+
+@@ -1629,6 +1649,9 @@
+
+ struct task_cputime cputime_expires;
+ struct list_head cpu_timers[3];
++#ifdef CONFIG_PREEMPT_RT_BASE
++ struct task_struct *posix_timer_list;
++#endif
+
+ /* process credentials */
+ const struct cred __rcu *real_cred; /* objective and real subjective task
+@@ -1659,10 +1682,15 @@
+ /* signal handlers */
+ struct signal_struct *signal;
+ struct sighand_struct *sighand;
++ struct sigqueue *sigqueue_cache;
+
+ sigset_t blocked, real_blocked;
+ sigset_t saved_sigmask; /* restored if set_restore_sigmask() was used */
+ struct sigpending pending;
++#ifdef CONFIG_PREEMPT_RT_FULL
++ /* TODO: move me into ->restart_block ? */
++ struct siginfo forced_info;
++#endif
+
+ unsigned long sas_ss_sp;
+ size_t sas_ss_size;
+@@ -1891,6 +1919,12 @@
+ /* bitmask and counter of trace recursion */
+ unsigned long trace_recursion;
+ #endif /* CONFIG_TRACING */
++#ifdef CONFIG_WAKEUP_LATENCY_HIST
++ u64 preempt_timestamp_hist;
++#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST
++ long timer_offset;
++#endif
++#endif
+ #ifdef CONFIG_KCOV
+ /* Coverage collection mode enabled for this task (0 if disabled). */
+ enum kcov_mode kcov_mode;
+@@ -1916,9 +1950,23 @@
+ unsigned int sequential_io;
+ unsigned int sequential_io_avg;
+ #endif
++#ifdef CONFIG_PREEMPT_RT_BASE
++ struct rcu_head put_rcu;
++ int softirq_nestcnt;
++ unsigned int softirqs_raised;
++#endif
++#ifdef CONFIG_PREEMPT_RT_FULL
++# if defined CONFIG_HIGHMEM || defined CONFIG_X86_32
++ int kmap_idx;
++ pte_t kmap_pte[KM_TYPE_NR];
++# endif
++#endif
+ #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
+ unsigned long task_state_change;
+ #endif
++#ifdef CONFIG_PREEMPT_RT_FULL
++ int xmit_recursion;
++#endif
+ int pagefault_disabled;
+ #ifdef CONFIG_MMU
+ struct task_struct *oom_reaper_list;
+@@ -1939,14 +1987,6 @@
+ # define arch_task_struct_size (sizeof(struct task_struct))
+ #endif
+
+-/* Future-safe accessor for struct task_struct's cpus_allowed. */
+-#define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed)
+-
+-static inline int tsk_nr_cpus_allowed(struct task_struct *p)
+-{
+- return p->nr_cpus_allowed;
+-}
+-
+ #define TNF_MIGRATED 0x01
+ #define TNF_NO_GROUP 0x02
+ #define TNF_SHARED 0x04
+@@ -2162,6 +2202,15 @@
+ extern void free_task(struct task_struct *tsk);
+ #define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
+
++#ifdef CONFIG_PREEMPT_RT_BASE
++extern void __put_task_struct_cb(struct rcu_head *rhp);
++
++static inline void put_task_struct(struct task_struct *t)
++{
++ if (atomic_dec_and_test(&t->usage))
++ call_rcu(&t->put_rcu, __put_task_struct_cb);
++}
++#else
+ extern void __put_task_struct(struct task_struct *t);
+
+ static inline void put_task_struct(struct task_struct *t)
+@@ -2169,6 +2218,7 @@
+ if (atomic_dec_and_test(&t->usage))
+ __put_task_struct(t);
+ }
++#endif
+
+ struct task_struct *task_rcu_dereference(struct task_struct **ptask);
+ struct task_struct *try_get_task_struct(struct task_struct **ptask);
+@@ -2210,6 +2260,7 @@
+ /*
+ * Per process flags
+ */
++#define PF_IN_SOFTIRQ 0x00000001 /* Task is serving softirq */
+ #define PF_EXITING 0x00000004 /* getting shut down */
+ #define PF_EXITPIDONE 0x00000008 /* pi exit done on shut down */
+ #define PF_VCPU 0x00000010 /* I'm a virtual CPU */
+@@ -2378,6 +2429,10 @@
+
+ extern int set_cpus_allowed_ptr(struct task_struct *p,
+ const struct cpumask *new_mask);
++int migrate_me(void);
++void tell_sched_cpu_down_begin(int cpu);
++void tell_sched_cpu_down_done(int cpu);
++
+ #else
+ static inline void do_set_cpus_allowed(struct task_struct *p,
+ const struct cpumask *new_mask)
+@@ -2390,6 +2445,9 @@
+ return -EINVAL;
+ return 0;
+ }
++static inline int migrate_me(void) { return 0; }
++static inline void tell_sched_cpu_down_begin(int cpu) { }
++static inline void tell_sched_cpu_down_done(int cpu) { }
+ #endif
+
+ #ifdef CONFIG_NO_HZ_COMMON
+@@ -2624,6 +2682,7 @@
+
+ extern int wake_up_state(struct task_struct *tsk, unsigned int state);
+ extern int wake_up_process(struct task_struct *tsk);
++extern int wake_up_lock_sleeper(struct task_struct * tsk);
+ extern void wake_up_new_task(struct task_struct *tsk);
+ #ifdef CONFIG_SMP
+ extern void kick_process(struct task_struct *tsk);
+@@ -2832,6 +2891,17 @@
+ __mmdrop(mm);
+ }
+
++#ifdef CONFIG_PREEMPT_RT_BASE
++extern void __mmdrop_delayed(struct rcu_head *rhp);
++static inline void mmdrop_delayed(struct mm_struct *mm)
++{
++ if (atomic_dec_and_test(&mm->mm_count))
++ call_rcu(&mm->delayed_drop, __mmdrop_delayed);
++}
++#else
++# define mmdrop_delayed(mm) mmdrop(mm)
++#endif
++
+ static inline bool mmget_not_zero(struct mm_struct *mm)
+ {
+ return atomic_inc_not_zero(&mm->mm_users);
+@@ -3168,6 +3238,43 @@
+ return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
+ }
+
++#ifdef CONFIG_PREEMPT_LAZY
++static inline void set_tsk_need_resched_lazy(struct task_struct *tsk)
++{
++ set_tsk_thread_flag(tsk,TIF_NEED_RESCHED_LAZY);
++}
++
++static inline void clear_tsk_need_resched_lazy(struct task_struct *tsk)
++{
++ clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED_LAZY);
++}
++
++static inline int test_tsk_need_resched_lazy(struct task_struct *tsk)
++{
++ return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED_LAZY));
++}
++
++static inline int need_resched_lazy(void)
++{
++ return test_thread_flag(TIF_NEED_RESCHED_LAZY);
++}
++
++static inline int need_resched_now(void)
++{
++ return test_thread_flag(TIF_NEED_RESCHED);
++}
++
++#else
++static inline void clear_tsk_need_resched_lazy(struct task_struct *tsk) { }
++static inline int need_resched_lazy(void) { return 0; }
++
++static inline int need_resched_now(void)
++{
++ return test_thread_flag(TIF_NEED_RESCHED);
++}
++
++#endif
++
+ static inline int restart_syscall(void)
+ {
+ set_tsk_thread_flag(current, TIF_SIGPENDING);
+@@ -3199,6 +3306,51 @@
+ return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p);
+ }
+
++static inline bool __task_is_stopped_or_traced(struct task_struct *task)
++{
++ if (task->state & (__TASK_STOPPED | __TASK_TRACED))
++ return true;
++#ifdef CONFIG_PREEMPT_RT_FULL
++ if (task->saved_state & (__TASK_STOPPED | __TASK_TRACED))
++ return true;
++#endif
++ return false;
++}
++
++static inline bool task_is_stopped_or_traced(struct task_struct *task)
++{
++ bool traced_stopped;
++
++#ifdef CONFIG_PREEMPT_RT_FULL
++ unsigned long flags;
++
++ raw_spin_lock_irqsave(&task->pi_lock, flags);
++ traced_stopped = __task_is_stopped_or_traced(task);
++ raw_spin_unlock_irqrestore(&task->pi_lock, flags);
++#else
++ traced_stopped = __task_is_stopped_or_traced(task);
++#endif
++ return traced_stopped;
++}
++
++static inline bool task_is_traced(struct task_struct *task)
++{
++ bool traced = false;
++
++ if (task->state & __TASK_TRACED)
++ return true;
++#ifdef CONFIG_PREEMPT_RT_FULL
++ /* in case the task is sleeping on tasklist_lock */
++ raw_spin_lock_irq(&task->pi_lock);
++ if (task->state & __TASK_TRACED)
++ traced = true;
++ else if (task->saved_state & __TASK_TRACED)
++ traced = true;
++ raw_spin_unlock_irq(&task->pi_lock);
++#endif
++ return traced;
++}
++
+ /*
+ * cond_resched() and cond_resched_lock(): latency reduction via
+ * explicit rescheduling in places that are safe. The return
+@@ -3220,12 +3372,16 @@
+ __cond_resched_lock(lock); \
+ })
+
++#ifndef CONFIG_PREEMPT_RT_FULL
+ extern int __cond_resched_softirq(void);
+
+ #define cond_resched_softirq() ({ \
+ ___might_sleep(__FILE__, __LINE__, SOFTIRQ_DISABLE_OFFSET); \
+ __cond_resched_softirq(); \
+ })
++#else
++# define cond_resched_softirq() cond_resched()
++#endif
+
+ static inline void cond_resched_rcu(void)
+ {
+@@ -3387,6 +3543,31 @@
+
+ #endif /* CONFIG_SMP */
+
++static inline int __migrate_disabled(struct task_struct *p)
++{
++#ifdef CONFIG_PREEMPT_RT_FULL
++ return p->migrate_disable;
++#else
++ return 0;
++#endif
++}
++
++/* Future-safe accessor for struct task_struct's cpus_allowed. */
++static inline const struct cpumask *tsk_cpus_allowed(struct task_struct *p)
++{
++ if (__migrate_disabled(p))
++ return cpumask_of(task_cpu(p));
++
++ return &p->cpus_allowed;
++}
++
++static inline int tsk_nr_cpus_allowed(struct task_struct *p)
++{
++ if (__migrate_disabled(p))
++ return 1;
++ return p->nr_cpus_allowed;
++}
++
+ extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
+ extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
+
+diff -Nur linux-4.8.15.orig/include/linux/seqlock.h linux-4.8.15/include/linux/seqlock.h
+--- linux-4.8.15.orig/include/linux/seqlock.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/seqlock.h 2017-01-01 17:07:15.899418461 +0100
+@@ -220,20 +220,30 @@
+ return __read_seqcount_retry(s, start);
+ }
+
+-
+-
+-static inline void raw_write_seqcount_begin(seqcount_t *s)
++static inline void __raw_write_seqcount_begin(seqcount_t *s)
+ {
+ s->sequence++;
+ smp_wmb();
+ }
+
+-static inline void raw_write_seqcount_end(seqcount_t *s)
++static inline void raw_write_seqcount_begin(seqcount_t *s)
++{
++ preempt_disable_rt();
++ __raw_write_seqcount_begin(s);
++}
++
++static inline void __raw_write_seqcount_end(seqcount_t *s)
+ {
+ smp_wmb();
+ s->sequence++;
+ }
+
++static inline void raw_write_seqcount_end(seqcount_t *s)
++{
++ __raw_write_seqcount_end(s);
++ preempt_enable_rt();
++}
++
+ /**
+ * raw_write_seqcount_barrier - do a seq write barrier
+ * @s: pointer to seqcount_t
+@@ -428,10 +438,32 @@
+ /*
+ * Read side functions for starting and finalizing a read side section.
+ */
++#ifndef CONFIG_PREEMPT_RT_FULL
+ static inline unsigned read_seqbegin(const seqlock_t *sl)
+ {
+ return read_seqcount_begin(&sl->seqcount);
+ }
++#else
++/*
++ * Starvation safe read side for RT
++ */
++static inline unsigned read_seqbegin(seqlock_t *sl)
++{
++ unsigned ret;
++
++repeat:
++ ret = ACCESS_ONCE(sl->seqcount.sequence);
++ if (unlikely(ret & 1)) {
++ /*
++ * Take the lock and let the writer proceed (i.e. evtl
++ * boost it), otherwise we could loop here forever.
++ */
++ spin_unlock_wait(&sl->lock);
++ goto repeat;
++ }
++ return ret;
++}
++#endif
+
+ static inline unsigned read_seqretry(const seqlock_t *sl, unsigned start)
+ {
+@@ -446,36 +478,45 @@
+ static inline void write_seqlock(seqlock_t *sl)
+ {
+ spin_lock(&sl->lock);
+- write_seqcount_begin(&sl->seqcount);
++ __raw_write_seqcount_begin(&sl->seqcount);
++}
++
++static inline int try_write_seqlock(seqlock_t *sl)
++{
++ if (spin_trylock(&sl->lock)) {
++ __raw_write_seqcount_begin(&sl->seqcount);
++ return 1;
++ }
++ return 0;
+ }
+
+ static inline void write_sequnlock(seqlock_t *sl)
+ {
+- write_seqcount_end(&sl->seqcount);
++ __raw_write_seqcount_end(&sl->seqcount);
+ spin_unlock(&sl->lock);
+ }
+
+ static inline void write_seqlock_bh(seqlock_t *sl)
+ {
+ spin_lock_bh(&sl->lock);
+- write_seqcount_begin(&sl->seqcount);
++ __raw_write_seqcount_begin(&sl->seqcount);
+ }
+
+ static inline void write_sequnlock_bh(seqlock_t *sl)
+ {
+- write_seqcount_end(&sl->seqcount);
++ __raw_write_seqcount_end(&sl->seqcount);
+ spin_unlock_bh(&sl->lock);
+ }
+
+ static inline void write_seqlock_irq(seqlock_t *sl)
+ {
+ spin_lock_irq(&sl->lock);
+- write_seqcount_begin(&sl->seqcount);
++ __raw_write_seqcount_begin(&sl->seqcount);
+ }
+
+ static inline void write_sequnlock_irq(seqlock_t *sl)
+ {
+- write_seqcount_end(&sl->seqcount);
++ __raw_write_seqcount_end(&sl->seqcount);
+ spin_unlock_irq(&sl->lock);
+ }
+
+@@ -484,7 +525,7 @@
+ unsigned long flags;
+
+ spin_lock_irqsave(&sl->lock, flags);
+- write_seqcount_begin(&sl->seqcount);
++ __raw_write_seqcount_begin(&sl->seqcount);
+ return flags;
+ }
+
+@@ -494,7 +535,7 @@
+ static inline void
+ write_sequnlock_irqrestore(seqlock_t *sl, unsigned long flags)
+ {
+- write_seqcount_end(&sl->seqcount);
++ __raw_write_seqcount_end(&sl->seqcount);
+ spin_unlock_irqrestore(&sl->lock, flags);
+ }
+
+diff -Nur linux-4.8.15.orig/include/linux/signal.h linux-4.8.15/include/linux/signal.h
+--- linux-4.8.15.orig/include/linux/signal.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/signal.h 2017-01-01 17:07:15.899418461 +0100
+@@ -233,6 +233,7 @@
+ }
+
+ extern void flush_sigqueue(struct sigpending *queue);
++extern void flush_task_sigqueue(struct task_struct *tsk);
+
+ /* Test if 'sig' is valid signal. Use this instead of testing _NSIG directly */
+ static inline int valid_signal(unsigned long sig)
+diff -Nur linux-4.8.15.orig/include/linux/skbuff.h linux-4.8.15/include/linux/skbuff.h
+--- linux-4.8.15.orig/include/linux/skbuff.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/skbuff.h 2017-01-01 17:07:15.915419486 +0100
+@@ -284,6 +284,7 @@
+
+ __u32 qlen;
+ spinlock_t lock;
++ raw_spinlock_t raw_lock;
+ };
+
+ struct sk_buff;
+@@ -1565,6 +1566,12 @@
+ __skb_queue_head_init(list);
+ }
+
++static inline void skb_queue_head_init_raw(struct sk_buff_head *list)
++{
++ raw_spin_lock_init(&list->raw_lock);
++ __skb_queue_head_init(list);
++}
++
+ static inline void skb_queue_head_init_class(struct sk_buff_head *list,
+ struct lock_class_key *class)
+ {
+diff -Nur linux-4.8.15.orig/include/linux/smp.h linux-4.8.15/include/linux/smp.h
+--- linux-4.8.15.orig/include/linux/smp.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/smp.h 2017-01-01 17:07:15.915419486 +0100
+@@ -185,6 +185,9 @@
+ #define get_cpu() ({ preempt_disable(); smp_processor_id(); })
+ #define put_cpu() preempt_enable()
+
++#define get_cpu_light() ({ migrate_disable(); smp_processor_id(); })
++#define put_cpu_light() migrate_enable()
++
+ /*
+ * Callback to arch code if there's nosmp or maxcpus=0 on the
+ * boot command line:
+diff -Nur linux-4.8.15.orig/include/linux/spinlock_api_smp.h linux-4.8.15/include/linux/spinlock_api_smp.h
+--- linux-4.8.15.orig/include/linux/spinlock_api_smp.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/spinlock_api_smp.h 2017-01-01 17:07:15.919419743 +0100
+@@ -189,6 +189,8 @@
+ return 0;
+ }
+
+-#include <linux/rwlock_api_smp.h>
++#ifndef CONFIG_PREEMPT_RT_FULL
++# include <linux/rwlock_api_smp.h>
++#endif
+
+ #endif /* __LINUX_SPINLOCK_API_SMP_H */
+diff -Nur linux-4.8.15.orig/include/linux/spinlock.h linux-4.8.15/include/linux/spinlock.h
+--- linux-4.8.15.orig/include/linux/spinlock.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/spinlock.h 2017-01-01 17:07:15.919419743 +0100
+@@ -271,7 +271,11 @@
+ #define raw_spin_can_lock(lock) (!raw_spin_is_locked(lock))
+
+ /* Include rwlock functions */
+-#include <linux/rwlock.h>
++#ifdef CONFIG_PREEMPT_RT_FULL
++# include <linux/rwlock_rt.h>
++#else
++# include <linux/rwlock.h>
++#endif
+
+ /*
+ * Pull the _spin_*()/_read_*()/_write_*() functions/declarations:
+@@ -282,6 +286,10 @@
+ # include <linux/spinlock_api_up.h>
+ #endif
+
++#ifdef CONFIG_PREEMPT_RT_FULL
++# include <linux/spinlock_rt.h>
++#else /* PREEMPT_RT_FULL */
++
+ /*
+ * Map the spin_lock functions to the raw variants for PREEMPT_RT=n
+ */
+@@ -347,6 +355,12 @@
+ raw_spin_unlock(&lock->rlock);
+ }
+
++static __always_inline int spin_unlock_no_deboost(spinlock_t *lock)
++{
++ raw_spin_unlock(&lock->rlock);
++ return 0;
++}
++
+ static __always_inline void spin_unlock_bh(spinlock_t *lock)
+ {
+ raw_spin_unlock_bh(&lock->rlock);
+@@ -416,4 +430,6 @@
+ #define atomic_dec_and_lock(atomic, lock) \
+ __cond_lock(lock, _atomic_dec_and_lock(atomic, lock))
+
++#endif /* !PREEMPT_RT_FULL */
++
+ #endif /* __LINUX_SPINLOCK_H */
+diff -Nur linux-4.8.15.orig/include/linux/spinlock_rt.h linux-4.8.15/include/linux/spinlock_rt.h
+--- linux-4.8.15.orig/include/linux/spinlock_rt.h 1970-01-01 01:00:00.000000000 +0100
++++ linux-4.8.15/include/linux/spinlock_rt.h 2017-01-01 17:07:15.923420007 +0100
+@@ -0,0 +1,165 @@
++#ifndef __LINUX_SPINLOCK_RT_H
++#define __LINUX_SPINLOCK_RT_H
++
++#ifndef __LINUX_SPINLOCK_H
++#error Do not include directly. Use spinlock.h
++#endif
++
++#include <linux/bug.h>
++
++extern void
++__rt_spin_lock_init(spinlock_t *lock, char *name, struct lock_class_key *key);
++
++#define spin_lock_init(slock) \
++do { \
++ static struct lock_class_key __key; \
++ \
++ rt_mutex_init(&(slock)->lock); \
++ __rt_spin_lock_init(slock, #slock, &__key); \
++} while (0)
++
++void __lockfunc rt_spin_lock__no_mg(spinlock_t *lock);
++void __lockfunc rt_spin_unlock__no_mg(spinlock_t *lock);
++int __lockfunc rt_spin_trylock__no_mg(spinlock_t *lock);
++
++extern void __lockfunc rt_spin_lock(spinlock_t *lock);
++extern unsigned long __lockfunc rt_spin_lock_trace_flags(spinlock_t *lock);
++extern void __lockfunc rt_spin_lock_nested(spinlock_t *lock, int subclass);
++extern void __lockfunc rt_spin_unlock(spinlock_t *lock);
++extern int __lockfunc rt_spin_unlock_no_deboost(spinlock_t *lock);
++extern void __lockfunc rt_spin_unlock_wait(spinlock_t *lock);
++extern int __lockfunc rt_spin_trylock_irqsave(spinlock_t *lock, unsigned long *flags);
++extern int __lockfunc rt_spin_trylock_bh(spinlock_t *lock);
++extern int __lockfunc rt_spin_trylock(spinlock_t *lock);
++extern int atomic_dec_and_spin_lock(atomic_t *atomic, spinlock_t *lock);
++
++/*
++ * lockdep-less calls, for derived types like rwlock:
++ * (for trylock they can use rt_mutex_trylock() directly.
++ */
++extern void __lockfunc __rt_spin_lock__no_mg(struct rt_mutex *lock);
++extern void __lockfunc __rt_spin_lock(struct rt_mutex *lock);
++extern void __lockfunc __rt_spin_unlock(struct rt_mutex *lock);
++extern int __lockfunc __rt_spin_trylock(struct rt_mutex *lock);
++
++#define spin_lock(lock) rt_spin_lock(lock)
++
++#define spin_lock_bh(lock) \
++ do { \
++ local_bh_disable(); \
++ rt_spin_lock(lock); \
++ } while (0)
++
++#define spin_lock_irq(lock) spin_lock(lock)
++
++#define spin_do_trylock(lock) __cond_lock(lock, rt_spin_trylock(lock))
++
++#define spin_trylock(lock) \
++({ \
++ int __locked; \
++ __locked = spin_do_trylock(lock); \
++ __locked; \
++})
++
++#ifdef CONFIG_LOCKDEP
++# define spin_lock_nested(lock, subclass) \
++ do { \
++ rt_spin_lock_nested(lock, subclass); \
++ } while (0)
++
++#define spin_lock_bh_nested(lock, subclass) \
++ do { \
++ local_bh_disable(); \
++ rt_spin_lock_nested(lock, subclass); \
++ } while (0)
++
++# define spin_lock_irqsave_nested(lock, flags, subclass) \
++ do { \
++ typecheck(unsigned long, flags); \
++ flags = 0; \
++ rt_spin_lock_nested(lock, subclass); \
++ } while (0)
++#else
++# define spin_lock_nested(lock, subclass) spin_lock(lock)
++# define spin_lock_bh_nested(lock, subclass) spin_lock_bh(lock)
++
++# define spin_lock_irqsave_nested(lock, flags, subclass) \
++ do { \
++ typecheck(unsigned long, flags); \
++ flags = 0; \
++ spin_lock(lock); \
++ } while (0)
++#endif
++
++#define spin_lock_irqsave(lock, flags) \
++ do { \
++ typecheck(unsigned long, flags); \
++ flags = 0; \
++ spin_lock(lock); \
++ } while (0)
++
++static inline unsigned long spin_lock_trace_flags(spinlock_t *lock)
++{
++ unsigned long flags = 0;
++#ifdef CONFIG_TRACE_IRQFLAGS
++ flags = rt_spin_lock_trace_flags(lock);
++#else
++ spin_lock(lock); /* lock_local */
++#endif
++ return flags;
++}
++
++/* FIXME: we need rt_spin_lock_nest_lock */
++#define spin_lock_nest_lock(lock, nest_lock) spin_lock_nested(lock, 0)
++
++#define spin_unlock(lock) rt_spin_unlock(lock)
++#define spin_unlock_no_deboost(lock) rt_spin_unlock_no_deboost(lock)
++
++#define spin_unlock_bh(lock) \
++ do { \
++ rt_spin_unlock(lock); \
++ local_bh_enable(); \
++ } while (0)
++
++#define spin_unlock_irq(lock) spin_unlock(lock)
++
++#define spin_unlock_irqrestore(lock, flags) \
++ do { \
++ typecheck(unsigned long, flags); \
++ (void) flags; \
++ spin_unlock(lock); \
++ } while (0)
++
++#define spin_trylock_bh(lock) __cond_lock(lock, rt_spin_trylock_bh(lock))
++#define spin_trylock_irq(lock) spin_trylock(lock)
++
++#define spin_trylock_irqsave(lock, flags) \
++ rt_spin_trylock_irqsave(lock, &(flags))
++
++#define spin_unlock_wait(lock) rt_spin_unlock_wait(lock)
++
++#ifdef CONFIG_GENERIC_LOCKBREAK
++# define spin_is_contended(lock) ((lock)->break_lock)
++#else
++# define spin_is_contended(lock) (((void)(lock), 0))
++#endif
++
++static inline int spin_can_lock(spinlock_t *lock)
++{
++ return !rt_mutex_is_locked(&lock->lock);
++}
++
++static inline int spin_is_locked(spinlock_t *lock)
++{
++ return rt_mutex_is_locked(&lock->lock);
++}
++
++static inline void assert_spin_locked(spinlock_t *lock)
++{
++ BUG_ON(!spin_is_locked(lock));
++}
++
++#define atomic_dec_and_lock(atomic, lock) \
++ atomic_dec_and_spin_lock(atomic, lock)
++
++#endif
+diff -Nur linux-4.8.15.orig/include/linux/spinlock_types.h linux-4.8.15/include/linux/spinlock_types.h
+--- linux-4.8.15.orig/include/linux/spinlock_types.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/spinlock_types.h 2017-01-01 17:07:15.923420007 +0100
+@@ -9,80 +9,15 @@
+ * Released under the General Public License (GPL).
+ */
+
+-#if defined(CONFIG_SMP)
+-# include <asm/spinlock_types.h>
+-#else
+-# include <linux/spinlock_types_up.h>
+-#endif
+-
+-#include <linux/lockdep.h>
+-
+-typedef struct raw_spinlock {
+- arch_spinlock_t raw_lock;
+-#ifdef CONFIG_GENERIC_LOCKBREAK
+- unsigned int break_lock;
+-#endif
+-#ifdef CONFIG_DEBUG_SPINLOCK
+- unsigned int magic, owner_cpu;
+- void *owner;
+-#endif
+-#ifdef CONFIG_DEBUG_LOCK_ALLOC
+- struct lockdep_map dep_map;
+-#endif
+-} raw_spinlock_t;
+-
+-#define SPINLOCK_MAGIC 0xdead4ead
+-
+-#define SPINLOCK_OWNER_INIT ((void *)-1L)
+-
+-#ifdef CONFIG_DEBUG_LOCK_ALLOC
+-# define SPIN_DEP_MAP_INIT(lockname) .dep_map = { .name = #lockname }
+-#else
+-# define SPIN_DEP_MAP_INIT(lockname)
+-#endif
++#include <linux/spinlock_types_raw.h>
+
+-#ifdef CONFIG_DEBUG_SPINLOCK
+-# define SPIN_DEBUG_INIT(lockname) \
+- .magic = SPINLOCK_MAGIC, \
+- .owner_cpu = -1, \
+- .owner = SPINLOCK_OWNER_INIT,
++#ifndef CONFIG_PREEMPT_RT_FULL
++# include <linux/spinlock_types_nort.h>
++# include <linux/rwlock_types.h>
+ #else
+-# define SPIN_DEBUG_INIT(lockname)
++# include <linux/rtmutex.h>
++# include <linux/spinlock_types_rt.h>
++# include <linux/rwlock_types_rt.h>
+ #endif
+
+-#define __RAW_SPIN_LOCK_INITIALIZER(lockname) \
+- { \
+- .raw_lock = __ARCH_SPIN_LOCK_UNLOCKED, \
+- SPIN_DEBUG_INIT(lockname) \
+- SPIN_DEP_MAP_INIT(lockname) }
+-
+-#define __RAW_SPIN_LOCK_UNLOCKED(lockname) \
+- (raw_spinlock_t) __RAW_SPIN_LOCK_INITIALIZER(lockname)
+-
+-#define DEFINE_RAW_SPINLOCK(x) raw_spinlock_t x = __RAW_SPIN_LOCK_UNLOCKED(x)
+-
+-typedef struct spinlock {
+- union {
+- struct raw_spinlock rlock;
+-
+-#ifdef CONFIG_DEBUG_LOCK_ALLOC
+-# define LOCK_PADSIZE (offsetof(struct raw_spinlock, dep_map))
+- struct {
+- u8 __padding[LOCK_PADSIZE];
+- struct lockdep_map dep_map;
+- };
+-#endif
+- };
+-} spinlock_t;
+-
+-#define __SPIN_LOCK_INITIALIZER(lockname) \
+- { { .rlock = __RAW_SPIN_LOCK_INITIALIZER(lockname) } }
+-
+-#define __SPIN_LOCK_UNLOCKED(lockname) \
+- (spinlock_t ) __SPIN_LOCK_INITIALIZER(lockname)
+-
+-#define DEFINE_SPINLOCK(x) spinlock_t x = __SPIN_LOCK_UNLOCKED(x)
+-
+-#include <linux/rwlock_types.h>
+-
+ #endif /* __LINUX_SPINLOCK_TYPES_H */
+diff -Nur linux-4.8.15.orig/include/linux/spinlock_types_nort.h linux-4.8.15/include/linux/spinlock_types_nort.h
+--- linux-4.8.15.orig/include/linux/spinlock_types_nort.h 1970-01-01 01:00:00.000000000 +0100
++++ linux-4.8.15/include/linux/spinlock_types_nort.h 2017-01-01 17:07:15.923420007 +0100
+@@ -0,0 +1,33 @@
++#ifndef __LINUX_SPINLOCK_TYPES_NORT_H
++#define __LINUX_SPINLOCK_TYPES_NORT_H
++
++#ifndef __LINUX_SPINLOCK_TYPES_H
++#error "Do not include directly. Include spinlock_types.h instead"
++#endif
++
++/*
++ * The non RT version maps spinlocks to raw_spinlocks
++ */
++typedef struct spinlock {
++ union {
++ struct raw_spinlock rlock;
++
++#ifdef CONFIG_DEBUG_LOCK_ALLOC
++# define LOCK_PADSIZE (offsetof(struct raw_spinlock, dep_map))
++ struct {
++ u8 __padding[LOCK_PADSIZE];
++ struct lockdep_map dep_map;
++ };
++#endif
++ };
++} spinlock_t;
++
++#define __SPIN_LOCK_INITIALIZER(lockname) \
++ { { .rlock = __RAW_SPIN_LOCK_INITIALIZER(lockname) } }
++
++#define __SPIN_LOCK_UNLOCKED(lockname) \
++ (spinlock_t ) __SPIN_LOCK_INITIALIZER(lockname)
++
++#define DEFINE_SPINLOCK(x) spinlock_t x = __SPIN_LOCK_UNLOCKED(x)
++
++#endif
+diff -Nur linux-4.8.15.orig/include/linux/spinlock_types_raw.h linux-4.8.15/include/linux/spinlock_types_raw.h
+--- linux-4.8.15.orig/include/linux/spinlock_types_raw.h 1970-01-01 01:00:00.000000000 +0100
++++ linux-4.8.15/include/linux/spinlock_types_raw.h 2017-01-01 17:07:15.923420007 +0100
+@@ -0,0 +1,56 @@
++#ifndef __LINUX_SPINLOCK_TYPES_RAW_H
++#define __LINUX_SPINLOCK_TYPES_RAW_H
++
++#if defined(CONFIG_SMP)
++# include <asm/spinlock_types.h>
++#else
++# include <linux/spinlock_types_up.h>
++#endif
++
++#include <linux/lockdep.h>
++
++typedef struct raw_spinlock {
++ arch_spinlock_t raw_lock;
++#ifdef CONFIG_GENERIC_LOCKBREAK
++ unsigned int break_lock;
++#endif
++#ifdef CONFIG_DEBUG_SPINLOCK
++ unsigned int magic, owner_cpu;
++ void *owner;
++#endif
++#ifdef CONFIG_DEBUG_LOCK_ALLOC
++ struct lockdep_map dep_map;
++#endif
++} raw_spinlock_t;
++
++#define SPINLOCK_MAGIC 0xdead4ead
++
++#define SPINLOCK_OWNER_INIT ((void *)-1L)
++
++#ifdef CONFIG_DEBUG_LOCK_ALLOC
++# define SPIN_DEP_MAP_INIT(lockname) .dep_map = { .name = #lockname }
++#else
++# define SPIN_DEP_MAP_INIT(lockname)
++#endif
++
++#ifdef CONFIG_DEBUG_SPINLOCK
++# define SPIN_DEBUG_INIT(lockname) \
++ .magic = SPINLOCK_MAGIC, \
++ .owner_cpu = -1, \
++ .owner = SPINLOCK_OWNER_INIT,
++#else
++# define SPIN_DEBUG_INIT(lockname)
++#endif
++
++#define __RAW_SPIN_LOCK_INITIALIZER(lockname) \
++ { \
++ .raw_lock = __ARCH_SPIN_LOCK_UNLOCKED, \
++ SPIN_DEBUG_INIT(lockname) \
++ SPIN_DEP_MAP_INIT(lockname) }
++
++#define __RAW_SPIN_LOCK_UNLOCKED(lockname) \
++ (raw_spinlock_t) __RAW_SPIN_LOCK_INITIALIZER(lockname)
++
++#define DEFINE_RAW_SPINLOCK(x) raw_spinlock_t x = __RAW_SPIN_LOCK_UNLOCKED(x)
++
++#endif
+diff -Nur linux-4.8.15.orig/include/linux/spinlock_types_rt.h linux-4.8.15/include/linux/spinlock_types_rt.h
+--- linux-4.8.15.orig/include/linux/spinlock_types_rt.h 1970-01-01 01:00:00.000000000 +0100
++++ linux-4.8.15/include/linux/spinlock_types_rt.h 2017-01-01 17:07:15.923420007 +0100
+@@ -0,0 +1,48 @@
++#ifndef __LINUX_SPINLOCK_TYPES_RT_H
++#define __LINUX_SPINLOCK_TYPES_RT_H
++
++#ifndef __LINUX_SPINLOCK_TYPES_H
++#error "Do not include directly. Include spinlock_types.h instead"
++#endif
++
++#include <linux/cache.h>
++
++/*
++ * PREEMPT_RT: spinlocks - an RT mutex plus lock-break field:
++ */
++typedef struct spinlock {
++ struct rt_mutex lock;
++ unsigned int break_lock;
++#ifdef CONFIG_DEBUG_LOCK_ALLOC
++ struct lockdep_map dep_map;
++#endif
++} spinlock_t;
++
++#ifdef CONFIG_DEBUG_RT_MUTEXES
++# define __RT_SPIN_INITIALIZER(name) \
++ { \
++ .wait_lock = __RAW_SPIN_LOCK_UNLOCKED(name.wait_lock), \
++ .save_state = 1, \
++ .file = __FILE__, \
++ .line = __LINE__ , \
++ }
++#else
++# define __RT_SPIN_INITIALIZER(name) \
++ { \
++ .wait_lock = __RAW_SPIN_LOCK_UNLOCKED(name.wait_lock), \
++ .save_state = 1, \
++ }
++#endif
++
++/*
++.wait_list = PLIST_HEAD_INIT_RAW((name).lock.wait_list, (name).lock.wait_lock)
++*/
++
++#define __SPIN_LOCK_UNLOCKED(name) \
++ { .lock = __RT_SPIN_INITIALIZER(name.lock), \
++ SPIN_DEP_MAP_INIT(name) }
++
++#define DEFINE_SPINLOCK(name) \
++ spinlock_t name = __SPIN_LOCK_UNLOCKED(name)
++
++#endif
+diff -Nur linux-4.8.15.orig/include/linux/srcu.h linux-4.8.15/include/linux/srcu.h
+--- linux-4.8.15.orig/include/linux/srcu.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/srcu.h 2017-01-01 17:07:15.923420007 +0100
+@@ -84,10 +84,10 @@
+
+ void process_srcu(struct work_struct *work);
+
+-#define __SRCU_STRUCT_INIT(name) \
++#define __SRCU_STRUCT_INIT(name, pcpu_name) \
+ { \
+ .completed = -300, \
+- .per_cpu_ref = &name##_srcu_array, \
++ .per_cpu_ref = &pcpu_name, \
+ .queue_lock = __SPIN_LOCK_UNLOCKED(name.queue_lock), \
+ .running = false, \
+ .batch_queue = RCU_BATCH_INIT(name.batch_queue), \
+@@ -119,7 +119,7 @@
+ */
+ #define __DEFINE_SRCU(name, is_static) \
+ static DEFINE_PER_CPU(struct srcu_struct_array, name##_srcu_array);\
+- is_static struct srcu_struct name = __SRCU_STRUCT_INIT(name)
++ is_static struct srcu_struct name = __SRCU_STRUCT_INIT(name, name##_srcu_array)
+ #define DEFINE_SRCU(name) __DEFINE_SRCU(name, /* not static */)
+ #define DEFINE_STATIC_SRCU(name) __DEFINE_SRCU(name, static)
+
+diff -Nur linux-4.8.15.orig/include/linux/suspend.h linux-4.8.15/include/linux/suspend.h
+--- linux-4.8.15.orig/include/linux/suspend.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/suspend.h 2017-01-01 17:07:15.927420258 +0100
+@@ -193,6 +193,12 @@
+ void (*end)(void);
+ };
+
++#if defined(CONFIG_SUSPEND) || defined(CONFIG_HIBERNATION)
++extern bool pm_in_action;
++#else
++# define pm_in_action false
++#endif
++
+ #ifdef CONFIG_SUSPEND
+ /**
+ * suspend_set_ops - set platform dependent suspend operations
+diff -Nur linux-4.8.15.orig/include/linux/swait.h linux-4.8.15/include/linux/swait.h
+--- linux-4.8.15.orig/include/linux/swait.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/swait.h 2017-01-01 17:07:15.931420510 +0100
+@@ -87,6 +87,7 @@
+ extern void swake_up(struct swait_queue_head *q);
+ extern void swake_up_all(struct swait_queue_head *q);
+ extern void swake_up_locked(struct swait_queue_head *q);
++extern void swake_up_all_locked(struct swait_queue_head *q);
+
+ extern void __prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait);
+ extern void prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait, int state);
+diff -Nur linux-4.8.15.orig/include/linux/swap.h linux-4.8.15/include/linux/swap.h
+--- linux-4.8.15.orig/include/linux/swap.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/swap.h 2017-01-01 17:07:15.931420510 +0100
+@@ -11,6 +11,7 @@
+ #include <linux/fs.h>
+ #include <linux/atomic.h>
+ #include <linux/page-flags.h>
++#include <linux/locallock.h>
+ #include <asm/page.h>
+
+ struct notifier_block;
+@@ -243,7 +244,8 @@
+ void *workingset_eviction(struct address_space *mapping, struct page *page);
+ bool workingset_refault(void *shadow);
+ void workingset_activation(struct page *page);
+-extern struct list_lru workingset_shadow_nodes;
++extern struct list_lru __workingset_shadow_nodes;
++DECLARE_LOCAL_IRQ_LOCK(workingset_shadow_lock);
+
+ static inline unsigned int workingset_node_pages(struct radix_tree_node *node)
+ {
+@@ -288,6 +290,7 @@
+
+
+ /* linux/mm/swap.c */
++DECLARE_LOCAL_IRQ_LOCK(swapvec_lock);
+ extern void lru_cache_add(struct page *);
+ extern void lru_cache_add_anon(struct page *page);
+ extern void lru_cache_add_file(struct page *page);
+diff -Nur linux-4.8.15.orig/include/linux/swork.h linux-4.8.15/include/linux/swork.h
+--- linux-4.8.15.orig/include/linux/swork.h 1970-01-01 01:00:00.000000000 +0100
++++ linux-4.8.15/include/linux/swork.h 2017-01-01 17:07:15.931420510 +0100
+@@ -0,0 +1,24 @@
++#ifndef _LINUX_SWORK_H
++#define _LINUX_SWORK_H
++
++#include <linux/list.h>
++
++struct swork_event {
++ struct list_head item;
++ unsigned long flags;
++ void (*func)(struct swork_event *);
++};
++
++static inline void INIT_SWORK(struct swork_event *event,
++ void (*func)(struct swork_event *))
++{
++ event->flags = 0;
++ event->func = func;
++}
++
++bool swork_queue(struct swork_event *sev);
++
++int swork_get(void);
++void swork_put(void);
++
++#endif /* _LINUX_SWORK_H */
+diff -Nur linux-4.8.15.orig/include/linux/thread_info.h linux-4.8.15/include/linux/thread_info.h
+--- linux-4.8.15.orig/include/linux/thread_info.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/thread_info.h 2017-01-01 17:07:15.931420510 +0100
+@@ -103,7 +103,17 @@
+ #define test_thread_flag(flag) \
+ test_ti_thread_flag(current_thread_info(), flag)
+
+-#define tif_need_resched() test_thread_flag(TIF_NEED_RESCHED)
++#ifdef CONFIG_PREEMPT_LAZY
++#define tif_need_resched() (test_thread_flag(TIF_NEED_RESCHED) || \
++ test_thread_flag(TIF_NEED_RESCHED_LAZY))
++#define tif_need_resched_now() (test_thread_flag(TIF_NEED_RESCHED))
++#define tif_need_resched_lazy() test_thread_flag(TIF_NEED_RESCHED_LAZY))
++
++#else
++#define tif_need_resched() test_thread_flag(TIF_NEED_RESCHED)
++#define tif_need_resched_now() test_thread_flag(TIF_NEED_RESCHED)
++#define tif_need_resched_lazy() 0
++#endif
+
+ #ifndef CONFIG_HAVE_ARCH_WITHIN_STACK_FRAMES
+ static inline int arch_within_stack_frames(const void * const stack,
+diff -Nur linux-4.8.15.orig/include/linux/timer.h linux-4.8.15/include/linux/timer.h
+--- linux-4.8.15.orig/include/linux/timer.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/timer.h 2017-01-01 17:07:15.935420777 +0100
+@@ -241,7 +241,7 @@
+
+ extern int try_to_del_timer_sync(struct timer_list *timer);
+
+-#ifdef CONFIG_SMP
++#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT_FULL)
+ extern int del_timer_sync(struct timer_list *timer);
+ #else
+ # define del_timer_sync(t) del_timer(t)
+diff -Nur linux-4.8.15.orig/include/linux/trace_events.h linux-4.8.15/include/linux/trace_events.h
+--- linux-4.8.15.orig/include/linux/trace_events.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/trace_events.h 2017-01-01 17:07:15.935420777 +0100
+@@ -56,6 +56,9 @@
+ unsigned char flags;
+ unsigned char preempt_count;
+ int pid;
++ unsigned short migrate_disable;
++ unsigned short padding;
++ unsigned char preempt_lazy_count;
+ };
+
+ #define TRACE_EVENT_TYPE_MAX \
+diff -Nur linux-4.8.15.orig/include/linux/uaccess.h linux-4.8.15/include/linux/uaccess.h
+--- linux-4.8.15.orig/include/linux/uaccess.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/uaccess.h 2017-01-01 17:07:15.935420777 +0100
+@@ -24,6 +24,7 @@
+ */
+ static inline void pagefault_disable(void)
+ {
++ migrate_disable();
+ pagefault_disabled_inc();
+ /*
+ * make sure to have issued the store before a pagefault
+@@ -40,6 +41,7 @@
+ */
+ barrier();
+ pagefault_disabled_dec();
++ migrate_enable();
+ }
+
+ /*
+diff -Nur linux-4.8.15.orig/include/linux/uprobes.h linux-4.8.15/include/linux/uprobes.h
+--- linux-4.8.15.orig/include/linux/uprobes.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/uprobes.h 2017-01-01 17:07:15.939421032 +0100
+@@ -27,6 +27,7 @@
+ #include <linux/errno.h>
+ #include <linux/rbtree.h>
+ #include <linux/types.h>
++#include <linux/wait.h>
+
+ struct vm_area_struct;
+ struct mm_struct;
+diff -Nur linux-4.8.15.orig/include/linux/vmstat.h linux-4.8.15/include/linux/vmstat.h
+--- linux-4.8.15.orig/include/linux/vmstat.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/vmstat.h 2017-01-01 17:07:15.951421804 +0100
+@@ -33,7 +33,9 @@
+ */
+ static inline void __count_vm_event(enum vm_event_item item)
+ {
++ preempt_disable_rt();
+ raw_cpu_inc(vm_event_states.event[item]);
++ preempt_enable_rt();
+ }
+
+ static inline void count_vm_event(enum vm_event_item item)
+@@ -43,7 +45,9 @@
+
+ static inline void __count_vm_events(enum vm_event_item item, long delta)
+ {
++ preempt_disable_rt();
+ raw_cpu_add(vm_event_states.event[item], delta);
++ preempt_enable_rt();
+ }
+
+ static inline void count_vm_events(enum vm_event_item item, long delta)
+diff -Nur linux-4.8.15.orig/include/linux/wait.h linux-4.8.15/include/linux/wait.h
+--- linux-4.8.15.orig/include/linux/wait.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/linux/wait.h 2017-01-01 17:07:15.955422055 +0100
+@@ -8,6 +8,7 @@
+ #include <linux/spinlock.h>
+ #include <asm/current.h>
+ #include <uapi/linux/wait.h>
++#include <linux/atomic.h>
+
+ typedef struct __wait_queue wait_queue_t;
+ typedef int (*wait_queue_func_t)(wait_queue_t *wait, unsigned mode, int flags, void *key);
+diff -Nur linux-4.8.15.orig/include/net/dst.h linux-4.8.15/include/net/dst.h
+--- linux-4.8.15.orig/include/net/dst.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/net/dst.h 2017-01-01 17:07:15.963422578 +0100
+@@ -446,7 +446,7 @@
+ static inline int dst_neigh_output(struct dst_entry *dst, struct neighbour *n,
+ struct sk_buff *skb)
+ {
+- const struct hh_cache *hh;
++ struct hh_cache *hh;
+
+ if (dst->pending_confirm) {
+ unsigned long now = jiffies;
+diff -Nur linux-4.8.15.orig/include/net/gen_stats.h linux-4.8.15/include/net/gen_stats.h
+--- linux-4.8.15.orig/include/net/gen_stats.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/net/gen_stats.h 2017-01-01 17:07:15.963422578 +0100
+@@ -5,6 +5,7 @@
+ #include <linux/socket.h>
+ #include <linux/rtnetlink.h>
+ #include <linux/pkt_sched.h>
++#include <net/net_seq_lock.h>
+
+ struct gnet_stats_basic_cpu {
+ struct gnet_stats_basic_packed bstats;
+@@ -33,11 +34,11 @@
+ spinlock_t *lock, struct gnet_dump *d,
+ int padattr);
+
+-int gnet_stats_copy_basic(const seqcount_t *running,
++int gnet_stats_copy_basic(net_seqlock_t *running,
+ struct gnet_dump *d,
+ struct gnet_stats_basic_cpu __percpu *cpu,
+ struct gnet_stats_basic_packed *b);
+-void __gnet_stats_copy_basic(const seqcount_t *running,
++void __gnet_stats_copy_basic(net_seqlock_t *running,
+ struct gnet_stats_basic_packed *bstats,
+ struct gnet_stats_basic_cpu __percpu *cpu,
+ struct gnet_stats_basic_packed *b);
+@@ -55,14 +56,14 @@
+ struct gnet_stats_basic_cpu __percpu *cpu_bstats,
+ struct gnet_stats_rate_est64 *rate_est,
+ spinlock_t *stats_lock,
+- seqcount_t *running, struct nlattr *opt);
++ net_seqlock_t *running, struct nlattr *opt);
+ void gen_kill_estimator(struct gnet_stats_basic_packed *bstats,
+ struct gnet_stats_rate_est64 *rate_est);
+ int gen_replace_estimator(struct gnet_stats_basic_packed *bstats,
+ struct gnet_stats_basic_cpu __percpu *cpu_bstats,
+ struct gnet_stats_rate_est64 *rate_est,
+ spinlock_t *stats_lock,
+- seqcount_t *running, struct nlattr *opt);
++ net_seqlock_t *running, struct nlattr *opt);
+ bool gen_estimator_active(const struct gnet_stats_basic_packed *bstats,
+ const struct gnet_stats_rate_est64 *rate_est);
+ #endif
+diff -Nur linux-4.8.15.orig/include/net/neighbour.h linux-4.8.15/include/net/neighbour.h
+--- linux-4.8.15.orig/include/net/neighbour.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/net/neighbour.h 2017-01-01 17:07:15.971423099 +0100
+@@ -446,7 +446,7 @@
+ }
+ #endif
+
+-static inline int neigh_hh_output(const struct hh_cache *hh, struct sk_buff *skb)
++static inline int neigh_hh_output(struct hh_cache *hh, struct sk_buff *skb)
+ {
+ unsigned int seq;
+ int hh_len;
+@@ -501,7 +501,7 @@
+
+ #define NEIGH_CB(skb) ((struct neighbour_cb *)(skb)->cb)
+
+-static inline void neigh_ha_snapshot(char *dst, const struct neighbour *n,
++static inline void neigh_ha_snapshot(char *dst, struct neighbour *n,
+ const struct net_device *dev)
+ {
+ unsigned int seq;
+diff -Nur linux-4.8.15.orig/include/net/netns/ipv4.h linux-4.8.15/include/net/netns/ipv4.h
+--- linux-4.8.15.orig/include/net/netns/ipv4.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/net/netns/ipv4.h 2017-01-01 17:07:15.975423350 +0100
+@@ -70,6 +70,7 @@
+
+ int sysctl_icmp_echo_ignore_all;
+ int sysctl_icmp_echo_ignore_broadcasts;
++ int sysctl_icmp_echo_sysrq;
+ int sysctl_icmp_ignore_bogus_error_responses;
+ int sysctl_icmp_ratelimit;
+ int sysctl_icmp_ratemask;
+diff -Nur linux-4.8.15.orig/include/net/net_seq_lock.h linux-4.8.15/include/net/net_seq_lock.h
+--- linux-4.8.15.orig/include/net/net_seq_lock.h 1970-01-01 01:00:00.000000000 +0100
++++ linux-4.8.15/include/net/net_seq_lock.h 2017-01-01 17:07:15.971423099 +0100
+@@ -0,0 +1,15 @@
++#ifndef __NET_NET_SEQ_LOCK_H__
++#define __NET_NET_SEQ_LOCK_H__
++
++#ifdef CONFIG_PREEMPT_RT_BASE
++# define net_seqlock_t seqlock_t
++# define net_seq_begin(__r) read_seqbegin(__r)
++# define net_seq_retry(__r, __s) read_seqretry(__r, __s)
++
++#else
++# define net_seqlock_t seqcount_t
++# define net_seq_begin(__r) read_seqcount_begin(__r)
++# define net_seq_retry(__r, __s) read_seqcount_retry(__r, __s)
++#endif
++
++#endif
+diff -Nur linux-4.8.15.orig/include/net/sch_generic.h linux-4.8.15/include/net/sch_generic.h
+--- linux-4.8.15.orig/include/net/sch_generic.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/include/net/sch_generic.h 2017-01-01 17:07:15.987424124 +0100
+@@ -10,6 +10,7 @@
+ #include <linux/dynamic_queue_limits.h>
+ #include <net/gen_stats.h>
+ #include <net/rtnetlink.h>
++#include <net/net_seq_lock.h>
+
+ struct Qdisc_ops;
+ struct qdisc_walker;
+@@ -78,7 +79,7 @@
+ struct sk_buff *gso_skb ____cacheline_aligned_in_smp;
+ struct sk_buff_head q;
+ struct gnet_stats_basic_packed bstats;
+- seqcount_t running;
++ net_seqlock_t running;
+ struct gnet_stats_queue qstats;
+ unsigned long state;
+ struct Qdisc *next_sched;
+@@ -90,13 +91,22 @@
+ spinlock_t busylock ____cacheline_aligned_in_smp;
+ };
+
+-static inline bool qdisc_is_running(const struct Qdisc *qdisc)
++static inline bool qdisc_is_running(struct Qdisc *qdisc)
+ {
++#ifdef CONFIG_PREEMPT_RT_BASE
++ return spin_is_locked(&qdisc->running.lock) ? true : false;
++#else
+ return (raw_read_seqcount(&qdisc->running) & 1) ? true : false;
++#endif
+ }
+
+ static inline bool qdisc_run_begin(struct Qdisc *qdisc)
+ {
++#ifdef CONFIG_PREEMPT_RT_BASE
++ if (try_write_seqlock(&qdisc->running))
++ return true;
++ return false;
++#else
+ if (qdisc_is_running(qdisc))
+ return false;
+ /* Variant of write_seqcount_begin() telling lockdep a trylock
+@@ -105,11 +115,16 @@
+ raw_write_seqcount_begin(&qdisc->running);
+ seqcount_acquire(&qdisc->running.dep_map, 0, 1, _RET_IP_);
+ return true;
++#endif
+ }
+
+ static inline void qdisc_run_end(struct Qdisc *qdisc)
+ {
++#ifdef CONFIG_PREEMPT_RT_BASE
++ write_sequnlock(&qdisc->running);
++#else
+ write_seqcount_end(&qdisc->running);
++#endif
+ }
+
+ static inline bool qdisc_may_bulk(const struct Qdisc *qdisc)
+@@ -300,7 +315,7 @@
+ return qdisc_lock(root);
+ }
+
+-static inline seqcount_t *qdisc_root_sleeping_running(const struct Qdisc *qdisc)
++static inline net_seqlock_t *qdisc_root_sleeping_running(const struct Qdisc *qdisc)
+ {
+ struct Qdisc *root = qdisc_root_sleeping(qdisc);
+
+diff -Nur linux-4.8.15.orig/include/trace/events/hist.h linux-4.8.15/include/trace/events/hist.h
+--- linux-4.8.15.orig/include/trace/events/hist.h 1970-01-01 01:00:00.000000000 +0100
++++ linux-4.8.15/include/trace/events/hist.h 2017-01-01 17:07:15.987424124 +0100
+@@ -0,0 +1,73 @@
++#undef TRACE_SYSTEM
++#define TRACE_SYSTEM hist
++
++#if !defined(_TRACE_HIST_H) || defined(TRACE_HEADER_MULTI_READ)
++#define _TRACE_HIST_H
++
++#include "latency_hist.h"
++#include <linux/tracepoint.h>
++
++#if !defined(CONFIG_PREEMPT_OFF_HIST) && !defined(CONFIG_INTERRUPT_OFF_HIST)
++#define trace_preemptirqsoff_hist(a, b)
++#define trace_preemptirqsoff_hist_rcuidle(a, b)
++#else
++TRACE_EVENT(preemptirqsoff_hist,
++
++ TP_PROTO(int reason, int starthist),
++
++ TP_ARGS(reason, starthist),
++
++ TP_STRUCT__entry(
++ __field(int, reason)
++ __field(int, starthist)
++ ),
++
++ TP_fast_assign(
++ __entry->reason = reason;
++ __entry->starthist = starthist;
++ ),
++
++ TP_printk("reason=%s starthist=%s", getaction(__entry->reason),
++ __entry->starthist ? "start" : "stop")
++);
++#endif
++
++#ifndef CONFIG_MISSED_TIMER_OFFSETS_HIST
++#define trace_hrtimer_interrupt(a, b, c, d)
++#else
++TRACE_EVENT(hrtimer_interrupt,
++
++ TP_PROTO(int cpu, long long offset, struct task_struct *curr,
++ struct task_struct *task),
++
++ TP_ARGS(cpu, offset, curr, task),
++
++ TP_STRUCT__entry(
++ __field(int, cpu)
++ __field(long long, offset)
++ __array(char, ccomm, TASK_COMM_LEN)
++ __field(int, cprio)
++ __array(char, tcomm, TASK_COMM_LEN)
++ __field(int, tprio)
++ ),
++
++ TP_fast_assign(
++ __entry->cpu = cpu;
++ __entry->offset = offset;
++ memcpy(__entry->ccomm, curr->comm, TASK_COMM_LEN);
++ __entry->cprio = curr->prio;
++ memcpy(__entry->tcomm, task != NULL ? task->comm : "<none>",
++ task != NULL ? TASK_COMM_LEN : 7);
++ __entry->tprio = task != NULL ? task->prio : -1;
++ ),
++
++ TP_printk("cpu=%d offset=%lld curr=%s[%d] thread=%s[%d]",
++ __entry->cpu, __entry->offset, __entry->ccomm,
++ __entry->cprio, __entry->tcomm, __entry->tprio)
++);
++#endif
++
++#endif /* _TRACE_HIST_H */
++
++/* This part must be outside protection */
++#include <trace/define_trace.h>
+diff -Nur linux-4.8.15.orig/include/trace/events/latency_hist.h linux-4.8.15/include/trace/events/latency_hist.h
+--- linux-4.8.15.orig/include/trace/events/latency_hist.h 1970-01-01 01:00:00.000000000 +0100
++++ linux-4.8.15/include/trace/events/latency_hist.h 2017-01-01 17:07:15.987424124 +0100
+@@ -0,0 +1,29 @@
++#ifndef _LATENCY_HIST_H
++#define _LATENCY_HIST_H
++
++enum hist_action {
++ IRQS_ON,
++ PREEMPT_ON,
++ TRACE_STOP,
++ IRQS_OFF,
++ PREEMPT_OFF,
++ TRACE_START,
++};
++
++static char *actions[] = {
++ "IRQS_ON",
++ "PREEMPT_ON",
++ "TRACE_STOP",
++ "IRQS_OFF",
++ "PREEMPT_OFF",
++ "TRACE_START",
++};
++
++static inline char *getaction(int action)
++{
++ if (action >= 0 && action <= sizeof(actions)/sizeof(actions[0]))
++ return actions[action];
++ return "unknown";
++}
++
++#endif /* _LATENCY_HIST_H */
+diff -Nur linux-4.8.15.orig/init/Kconfig linux-4.8.15/init/Kconfig
+--- linux-4.8.15.orig/init/Kconfig 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/init/Kconfig 2017-01-01 17:07:15.987424124 +0100
+@@ -496,7 +496,7 @@
+
+ config RCU_EXPERT
+ bool "Make expert-level adjustments to RCU configuration"
+- default n
++ default y if PREEMPT_RT_FULL
+ help
+ This option needs to be enabled if you wish to make
+ expert-level adjustments to RCU configuration. By default,
+@@ -613,7 +613,7 @@
+
+ config RCU_FAST_NO_HZ
+ bool "Accelerate last non-dyntick-idle CPU's grace periods"
+- depends on NO_HZ_COMMON && SMP && RCU_EXPERT
++ depends on NO_HZ_COMMON && SMP && RCU_EXPERT && !PREEMPT_RT_FULL
+ default n
+ help
+ This option permits CPUs to enter dynticks-idle state even if
+@@ -640,7 +640,7 @@
+ config RCU_BOOST
+ bool "Enable RCU priority boosting"
+ depends on RT_MUTEXES && PREEMPT_RCU && RCU_EXPERT
+- default n
++ default y if PREEMPT_RT_FULL
+ help
+ This option boosts the priority of preempted RCU readers that
+ block the current preemptible RCU grace period for too long.
+@@ -771,19 +771,6 @@
+
+ endchoice
+
+-config RCU_EXPEDITE_BOOT
+- bool
+- default n
+- help
+- This option enables expedited grace periods at boot time,
+- as if rcu_expedite_gp() had been invoked early in boot.
+- The corresponding rcu_unexpedite_gp() is invoked from
+- rcu_end_inkernel_boot(), which is intended to be invoked
+- at the end of the kernel-only boot sequence, just before
+- init is exec'ed.
+-
+- Accept the default if unsure.
+-
+ endmenu # "RCU Subsystem"
+
+ config BUILD_BIN2C
+@@ -1054,6 +1041,7 @@
+ config RT_GROUP_SCHED
+ bool "Group scheduling for SCHED_RR/FIFO"
+ depends on CGROUP_SCHED
++ depends on !PREEMPT_RT_FULL
+ default n
+ help
+ This feature lets you explicitly allocate real CPU bandwidth
+@@ -1761,6 +1749,7 @@
+
+ config SLAB
+ bool "SLAB"
++ depends on !PREEMPT_RT_FULL
+ select HAVE_HARDENED_USERCOPY_ALLOCATOR
+ help
+ The regular slab allocator that is established and known to work
+@@ -1781,6 +1770,7 @@
+ config SLOB
+ depends on EXPERT
+ bool "SLOB (Simple Allocator)"
++ depends on !PREEMPT_RT_FULL
+ help
+ SLOB replaces the stock allocator with a drastically simpler
+ allocator. SLOB is generally more space efficient but
+@@ -1799,7 +1789,7 @@
+
+ config SLUB_CPU_PARTIAL
+ default y
+- depends on SLUB && SMP
++ depends on SLUB && SMP && !PREEMPT_RT_FULL
+ bool "SLUB per cpu partial cache"
+ help
+ Per cpu partial caches accellerate objects allocation and freeing
+diff -Nur linux-4.8.15.orig/init/main.c linux-4.8.15/init/main.c
+--- linux-4.8.15.orig/init/main.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/init/main.c 2017-01-01 17:07:15.991424381 +0100
+@@ -507,6 +507,7 @@
+ setup_command_line(command_line);
+ setup_nr_cpu_ids();
+ setup_per_cpu_areas();
++ softirq_early_init();
+ boot_cpu_state_init();
+ smp_prepare_boot_cpu(); /* arch-specific boot-cpu hooks */
+
+diff -Nur linux-4.8.15.orig/init/Makefile linux-4.8.15/init/Makefile
+--- linux-4.8.15.orig/init/Makefile 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/init/Makefile 2017-01-01 17:07:15.991424381 +0100
+@@ -33,4 +33,4 @@
+ include/generated/compile.h: FORCE
+ @$($(quiet)chk_compile.h)
+ $(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkcompile_h $@ \
+- "$(UTS_MACHINE)" "$(CONFIG_SMP)" "$(CONFIG_PREEMPT)" "$(CC) $(KBUILD_CFLAGS)"
++ "$(UTS_MACHINE)" "$(CONFIG_SMP)" "$(CONFIG_PREEMPT)" "$(CONFIG_PREEMPT_RT_FULL)" "$(CC) $(KBUILD_CFLAGS)"
+diff -Nur linux-4.8.15.orig/ipc/msg.c linux-4.8.15/ipc/msg.c
+--- linux-4.8.15.orig/ipc/msg.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/ipc/msg.c 2017-01-01 17:07:15.991424381 +0100
+@@ -183,20 +183,14 @@
+ }
+ }
+
+-static void expunge_all(struct msg_queue *msq, int res)
++static void expunge_all(struct msg_queue *msq, int res,
++ struct wake_q_head *wake_q)
+ {
+ struct msg_receiver *msr, *t;
+
+ list_for_each_entry_safe(msr, t, &msq->q_receivers, r_list) {
+- msr->r_msg = NULL; /* initialize expunge ordering */
+- wake_up_process(msr->r_tsk);
+- /*
+- * Ensure that the wakeup is visible before setting r_msg as
+- * the receiving end depends on it: either spinning on a nil,
+- * or dealing with -EAGAIN cases. See lockless receive part 1
+- * and 2 in do_msgrcv().
+- */
+- smp_wmb(); /* barrier (B) */
++
++ wake_q_add(wake_q, msr->r_tsk);
+ msr->r_msg = ERR_PTR(res);
+ }
+ }
+@@ -213,11 +207,13 @@
+ {
+ struct msg_msg *msg, *t;
+ struct msg_queue *msq = container_of(ipcp, struct msg_queue, q_perm);
++ WAKE_Q(wake_q);
+
+- expunge_all(msq, -EIDRM);
++ expunge_all(msq, -EIDRM, &wake_q);
+ ss_wakeup(&msq->q_senders, 1);
+ msg_rmid(ns, msq);
+ ipc_unlock_object(&msq->q_perm);
++ wake_up_q(&wake_q);
+ rcu_read_unlock();
+
+ list_for_each_entry_safe(msg, t, &msq->q_messages, m_list) {
+@@ -342,6 +338,7 @@
+ struct kern_ipc_perm *ipcp;
+ struct msqid64_ds uninitialized_var(msqid64);
+ struct msg_queue *msq;
++ WAKE_Q(wake_q);
+ int err;
+
+ if (cmd == IPC_SET) {
+@@ -389,7 +386,7 @@
+ /* sleeping receivers might be excluded by
+ * stricter permissions.
+ */
+- expunge_all(msq, -EAGAIN);
++ expunge_all(msq, -EAGAIN, &wake_q);
+ /* sleeping senders might be able to send
+ * due to a larger queue size.
+ */
+@@ -402,6 +399,7 @@
+
+ out_unlock0:
+ ipc_unlock_object(&msq->q_perm);
++ wake_up_q(&wake_q);
+ out_unlock1:
+ rcu_read_unlock();
+ out_up:
+@@ -566,7 +564,8 @@
+ return 0;
+ }
+
+-static inline int pipelined_send(struct msg_queue *msq, struct msg_msg *msg)
++static inline int pipelined_send(struct msg_queue *msq, struct msg_msg *msg,
++ struct wake_q_head *wake_q)
+ {
+ struct msg_receiver *msr, *t;
+
+@@ -577,27 +576,13 @@
+
+ list_del(&msr->r_list);
+ if (msr->r_maxsize < msg->m_ts) {
+- /* initialize pipelined send ordering */
+- msr->r_msg = NULL;
+- wake_up_process(msr->r_tsk);
+- /* barrier (B) see barrier comment below */
+- smp_wmb();
++ wake_q_add(wake_q, msr->r_tsk);
+ msr->r_msg = ERR_PTR(-E2BIG);
+ } else {
+- msr->r_msg = NULL;
+ msq->q_lrpid = task_pid_vnr(msr->r_tsk);
+ msq->q_rtime = get_seconds();
+- wake_up_process(msr->r_tsk);
+- /*
+- * Ensure that the wakeup is visible before
+- * setting r_msg, as the receiving can otherwise
+- * exit - once r_msg is set, the receiver can
+- * continue. See lockless receive part 1 and 2
+- * in do_msgrcv(). Barrier (B).
+- */
+- smp_wmb();
++ wake_q_add(wake_q, msr->r_tsk);
+ msr->r_msg = msg;
+-
+ return 1;
+ }
+ }
+@@ -613,6 +598,7 @@
+ struct msg_msg *msg;
+ int err;
+ struct ipc_namespace *ns;
++ WAKE_Q(wake_q);
+
+ ns = current->nsproxy->ipc_ns;
+
+@@ -698,7 +684,7 @@
+ msq->q_lspid = task_tgid_vnr(current);
+ msq->q_stime = get_seconds();
+
+- if (!pipelined_send(msq, msg)) {
++ if (!pipelined_send(msq, msg, &wake_q)) {
+ /* no one is waiting for this message, enqueue it */
+ list_add_tail(&msg->m_list, &msq->q_messages);
+ msq->q_cbytes += msgsz;
+@@ -712,6 +698,7 @@
+
+ out_unlock0:
+ ipc_unlock_object(&msq->q_perm);
++ wake_up_q(&wake_q);
+ out_unlock1:
+ rcu_read_unlock();
+ if (msg != NULL)
+@@ -932,57 +919,25 @@
+ rcu_read_lock();
+
+ /* Lockless receive, part 2:
+- * Wait until pipelined_send or expunge_all are outside of
+- * wake_up_process(). There is a race with exit(), see
+- * ipc/mqueue.c for the details. The correct serialization
+- * ensures that a receiver cannot continue without the wakeup
+- * being visibible _before_ setting r_msg:
++ * The work in pipelined_send() and expunge_all():
++ * - Set pointer to message
++ * - Queue the receiver task for later wakeup
++ * - Wake up the process after the lock is dropped.
+ *
+- * CPU 0 CPU 1
+- * <loop receiver>
+- * smp_rmb(); (A) <-- pair -. <waker thread>
+- * <load ->r_msg> | msr->r_msg = NULL;
+- * | wake_up_process();
+- * <continue> `------> smp_wmb(); (B)
+- * msr->r_msg = msg;
+- *
+- * Where (A) orders the message value read and where (B) orders
+- * the write to the r_msg -- done in both pipelined_send and
+- * expunge_all.
++ * Should the process wake up before this wakeup (due to a
++ * signal) it will either see the message and continue …
+ */
+- for (;;) {
+- /*
+- * Pairs with writer barrier in pipelined_send
+- * or expunge_all.
+- */
+- smp_rmb(); /* barrier (A) */
+- msg = (struct msg_msg *)msr_d.r_msg;
+- if (msg)
+- break;
+
+- /*
+- * The cpu_relax() call is a compiler barrier
+- * which forces everything in this loop to be
+- * re-loaded.
+- */
+- cpu_relax();
+- }
+-
+- /* Lockless receive, part 3:
+- * If there is a message or an error then accept it without
+- * locking.
+- */
++ msg = (struct msg_msg *)msr_d.r_msg;
+ if (msg != ERR_PTR(-EAGAIN))
+ goto out_unlock1;
+
+- /* Lockless receive, part 3:
+- * Acquire the queue spinlock.
+- */
++ /*
++ * … or see -EAGAIN, acquire the lock to check the message
++ * again.
++ */
+ ipc_lock_object(&msq->q_perm);
+
+- /* Lockless receive, part 4:
+- * Repeat test after acquiring the spinlock.
+- */
+ msg = (struct msg_msg *)msr_d.r_msg;
+ if (msg != ERR_PTR(-EAGAIN))
+ goto out_unlock0;
+diff -Nur linux-4.8.15.orig/ipc/sem.c linux-4.8.15/ipc/sem.c
+--- linux-4.8.15.orig/ipc/sem.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/ipc/sem.c 2017-01-01 17:07:15.991424381 +0100
+@@ -712,6 +712,13 @@
+ static void wake_up_sem_queue_prepare(struct list_head *pt,
+ struct sem_queue *q, int error)
+ {
++#ifdef CONFIG_PREEMPT_RT_BASE
++ struct task_struct *p = q->sleeper;
++ get_task_struct(p);
++ q->status = error;
++ wake_up_process(p);
++ put_task_struct(p);
++#else
+ if (list_empty(pt)) {
+ /*
+ * Hold preempt off so that we don't get preempted and have the
+@@ -723,6 +730,7 @@
+ q->pid = error;
+
+ list_add_tail(&q->list, pt);
++#endif
+ }
+
+ /**
+@@ -736,6 +744,7 @@
+ */
+ static void wake_up_sem_queue_do(struct list_head *pt)
+ {
++#ifndef CONFIG_PREEMPT_RT_BASE
+ struct sem_queue *q, *t;
+ int did_something;
+
+@@ -748,6 +757,7 @@
+ }
+ if (did_something)
+ preempt_enable();
++#endif
+ }
+
+ static void unlink_queue(struct sem_array *sma, struct sem_queue *q)
+diff -Nur linux-4.8.15.orig/kernel/cgroup.c linux-4.8.15/kernel/cgroup.c
+--- linux-4.8.15.orig/kernel/cgroup.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/cgroup.c 2017-01-01 17:07:15.999424895 +0100
+@@ -5027,10 +5027,10 @@
+ queue_work(cgroup_destroy_wq, &css->destroy_work);
+ }
+
+-static void css_release_work_fn(struct work_struct *work)
++static void css_release_work_fn(struct swork_event *sev)
+ {
+ struct cgroup_subsys_state *css =
+- container_of(work, struct cgroup_subsys_state, destroy_work);
++ container_of(sev, struct cgroup_subsys_state, destroy_swork);
+ struct cgroup_subsys *ss = css->ss;
+ struct cgroup *cgrp = css->cgroup;
+
+@@ -5071,8 +5071,8 @@
+ struct cgroup_subsys_state *css =
+ container_of(ref, struct cgroup_subsys_state, refcnt);
+
+- INIT_WORK(&css->destroy_work, css_release_work_fn);
+- queue_work(cgroup_destroy_wq, &css->destroy_work);
++ INIT_SWORK(&css->destroy_swork, css_release_work_fn);
++ swork_queue(&css->destroy_swork);
+ }
+
+ static void init_and_link_css(struct cgroup_subsys_state *css,
+@@ -5716,6 +5716,7 @@
+ */
+ cgroup_destroy_wq = alloc_workqueue("cgroup_destroy", 0, 1);
+ BUG_ON(!cgroup_destroy_wq);
++ BUG_ON(swork_get());
+
+ /*
+ * Used to destroy pidlists and separate to serve as flush domain.
+diff -Nur linux-4.8.15.orig/kernel/cpu.c linux-4.8.15/kernel/cpu.c
+--- linux-4.8.15.orig/kernel/cpu.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/cpu.c 2017-01-01 17:07:15.999424895 +0100
+@@ -152,8 +152,8 @@
+ #endif
+ } cpu_hotplug = {
+ .active_writer = NULL,
+- .wq = __WAIT_QUEUE_HEAD_INITIALIZER(cpu_hotplug.wq),
+ .lock = __MUTEX_INITIALIZER(cpu_hotplug.lock),
++ .wq = __WAIT_QUEUE_HEAD_INITIALIZER(cpu_hotplug.wq),
+ #ifdef CONFIG_DEBUG_LOCK_ALLOC
+ .dep_map = {.name = "cpu_hotplug.lock" },
+ #endif
+@@ -166,6 +166,289 @@
+ #define cpuhp_lock_acquire() lock_map_acquire(&cpu_hotplug.dep_map)
+ #define cpuhp_lock_release() lock_map_release(&cpu_hotplug.dep_map)
+
++/**
++ * hotplug_pcp - per cpu hotplug descriptor
++ * @unplug: set when pin_current_cpu() needs to sync tasks
++ * @sync_tsk: the task that waits for tasks to finish pinned sections
++ * @refcount: counter of tasks in pinned sections
++ * @grab_lock: set when the tasks entering pinned sections should wait
++ * @synced: notifier for @sync_tsk to tell cpu_down it's finished
++ * @mutex: the mutex to make tasks wait (used when @grab_lock is true)
++ * @mutex_init: zero if the mutex hasn't been initialized yet.
++ *
++ * Although @unplug and @sync_tsk may point to the same task, the @unplug
++ * is used as a flag and still exists after @sync_tsk has exited and
++ * @sync_tsk set to NULL.
++ */
++struct hotplug_pcp {
++ struct task_struct *unplug;
++ struct task_struct *sync_tsk;
++ int refcount;
++ int grab_lock;
++ struct completion synced;
++ struct completion unplug_wait;
++#ifdef CONFIG_PREEMPT_RT_FULL
++ /*
++ * Note, on PREEMPT_RT, the hotplug lock must save the state of
++ * the task, otherwise the mutex will cause the task to fail
++ * to sleep when required. (Because it's called from migrate_disable())
++ *
++ * The spinlock_t on PREEMPT_RT is a mutex that saves the task's
++ * state.
++ */
++ spinlock_t lock;
++#else
++ struct mutex mutex;
++#endif
++ int mutex_init;
++};
++
++#ifdef CONFIG_PREEMPT_RT_FULL
++# define hotplug_lock(hp) rt_spin_lock__no_mg(&(hp)->lock)
++# define hotplug_unlock(hp) rt_spin_unlock__no_mg(&(hp)->lock)
++#else
++# define hotplug_lock(hp) mutex_lock(&(hp)->mutex)
++# define hotplug_unlock(hp) mutex_unlock(&(hp)->mutex)
++#endif
++
++static DEFINE_PER_CPU(struct hotplug_pcp, hotplug_pcp);
++
++/**
++ * pin_current_cpu - Prevent the current cpu from being unplugged
++ *
++ * Lightweight version of get_online_cpus() to prevent cpu from being
++ * unplugged when code runs in a migration disabled region.
++ *
++ * Must be called with preemption disabled (preempt_count = 1)!
++ */
++void pin_current_cpu(void)
++{
++ struct hotplug_pcp *hp;
++ int force = 0;
++
++retry:
++ hp = this_cpu_ptr(&hotplug_pcp);
++
++ if (!hp->unplug || hp->refcount || force || preempt_count() > 1 ||
++ hp->unplug == current) {
++ hp->refcount++;
++ return;
++ }
++ if (hp->grab_lock) {
++ preempt_enable();
++ hotplug_lock(hp);
++ hotplug_unlock(hp);
++ } else {
++ preempt_enable();
++ /*
++ * Try to push this task off of this CPU.
++ */
++ if (!migrate_me()) {
++ preempt_disable();
++ hp = this_cpu_ptr(&hotplug_pcp);
++ if (!hp->grab_lock) {
++ /*
++ * Just let it continue it's already pinned
++ * or about to sleep.
++ */
++ force = 1;
++ goto retry;
++ }
++ preempt_enable();
++ }
++ }
++ preempt_disable();
++ goto retry;
++}
++
++/**
++ * unpin_current_cpu - Allow unplug of current cpu
++ *
++ * Must be called with preemption or interrupts disabled!
++ */
++void unpin_current_cpu(void)
++{
++ struct hotplug_pcp *hp = this_cpu_ptr(&hotplug_pcp);
++
++ WARN_ON(hp->refcount <= 0);
++
++ /* This is safe. sync_unplug_thread is pinned to this cpu */
++ if (!--hp->refcount && hp->unplug && hp->unplug != current)
++ wake_up_process(hp->unplug);
++}
++
++static void wait_for_pinned_cpus(struct hotplug_pcp *hp)
++{
++ set_current_state(TASK_UNINTERRUPTIBLE);
++ while (hp->refcount) {
++ schedule_preempt_disabled();
++ set_current_state(TASK_UNINTERRUPTIBLE);
++ }
++}
++
++static int sync_unplug_thread(void *data)
++{
++ struct hotplug_pcp *hp = data;
++
++ wait_for_completion(&hp->unplug_wait);
++ preempt_disable();
++ hp->unplug = current;
++ wait_for_pinned_cpus(hp);
++
++ /*
++ * This thread will synchronize the cpu_down() with threads
++ * that have pinned the CPU. When the pinned CPU count reaches
++ * zero, we inform the cpu_down code to continue to the next step.
++ */
++ set_current_state(TASK_UNINTERRUPTIBLE);
++ preempt_enable();
++ complete(&hp->synced);
++
++ /*
++ * If all succeeds, the next step will need tasks to wait till
++ * the CPU is offline before continuing. To do this, the grab_lock
++ * is set and tasks going into pin_current_cpu() will block on the
++ * mutex. But we still need to wait for those that are already in
++ * pinned CPU sections. If the cpu_down() failed, the kthread_should_stop()
++ * will kick this thread out.
++ */
++ while (!hp->grab_lock && !kthread_should_stop()) {
++ schedule();
++ set_current_state(TASK_UNINTERRUPTIBLE);
++ }
++
++ /* Make sure grab_lock is seen before we see a stale completion */
++ smp_mb();
++
++ /*
++ * Now just before cpu_down() enters stop machine, we need to make
++ * sure all tasks that are in pinned CPU sections are out, and new
++ * tasks will now grab the lock, keeping them from entering pinned
++ * CPU sections.
++ */
++ if (!kthread_should_stop()) {
++ preempt_disable();
++ wait_for_pinned_cpus(hp);
++ preempt_enable();
++ complete(&hp->synced);
++ }
++
++ set_current_state(TASK_UNINTERRUPTIBLE);
++ while (!kthread_should_stop()) {
++ schedule();
++ set_current_state(TASK_UNINTERRUPTIBLE);
++ }
++ set_current_state(TASK_RUNNING);
++
++ /*
++ * Force this thread off this CPU as it's going down and
++ * we don't want any more work on this CPU.
++ */
++ current->flags &= ~PF_NO_SETAFFINITY;
++ set_cpus_allowed_ptr(current, cpu_present_mask);
++ migrate_me();
++ return 0;
++}
++
++static void __cpu_unplug_sync(struct hotplug_pcp *hp)
++{
++ wake_up_process(hp->sync_tsk);
++ wait_for_completion(&hp->synced);
++}
++
++static void __cpu_unplug_wait(unsigned int cpu)
++{
++ struct hotplug_pcp *hp = &per_cpu(hotplug_pcp, cpu);
++
++ complete(&hp->unplug_wait);
++ wait_for_completion(&hp->synced);
++}
++
++/*
++ * Start the sync_unplug_thread on the target cpu and wait for it to
++ * complete.
++ */
++static int cpu_unplug_begin(unsigned int cpu)
++{
++ struct hotplug_pcp *hp = &per_cpu(hotplug_pcp, cpu);
++ int err;
++
++ /* Protected by cpu_hotplug.lock */
++ if (!hp->mutex_init) {
++#ifdef CONFIG_PREEMPT_RT_FULL
++ spin_lock_init(&hp->lock);
++#else
++ mutex_init(&hp->mutex);
++#endif
++ hp->mutex_init = 1;
++ }
++
++ /* Inform the scheduler to migrate tasks off this CPU */
++ tell_sched_cpu_down_begin(cpu);
++
++ init_completion(&hp->synced);
++ init_completion(&hp->unplug_wait);
++
++ hp->sync_tsk = kthread_create(sync_unplug_thread, hp, "sync_unplug/%d", cpu);
++ if (IS_ERR(hp->sync_tsk)) {
++ err = PTR_ERR(hp->sync_tsk);
++ hp->sync_tsk = NULL;
++ return err;
++ }
++ kthread_bind(hp->sync_tsk, cpu);
++
++ /*
++ * Wait for tasks to get out of the pinned sections,
++ * it's still OK if new tasks enter. Some CPU notifiers will
++ * wait for tasks that are going to enter these sections and
++ * we must not have them block.
++ */
++ wake_up_process(hp->sync_tsk);
++ return 0;
++}
++
++static void cpu_unplug_sync(unsigned int cpu)
++{
++ struct hotplug_pcp *hp = &per_cpu(hotplug_pcp, cpu);
++
++ init_completion(&hp->synced);
++ /* The completion needs to be initialzied before setting grab_lock */
++ smp_wmb();
++
++ /* Grab the mutex before setting grab_lock */
++ hotplug_lock(hp);
++ hp->grab_lock = 1;
++
++ /*
++ * The CPU notifiers have been completed.
++ * Wait for tasks to get out of pinned CPU sections and have new
++ * tasks block until the CPU is completely down.
++ */
++ __cpu_unplug_sync(hp);
++
++ /* All done with the sync thread */
++ kthread_stop(hp->sync_tsk);
++ hp->sync_tsk = NULL;
++}
++
++static void cpu_unplug_done(unsigned int cpu)
++{
++ struct hotplug_pcp *hp = &per_cpu(hotplug_pcp, cpu);
++
++ hp->unplug = NULL;
++ /* Let all tasks know cpu unplug is finished before cleaning up */
++ smp_wmb();
++
++ if (hp->sync_tsk)
++ kthread_stop(hp->sync_tsk);
++
++ if (hp->grab_lock) {
++ hotplug_unlock(hp);
++ /* protected by cpu_hotplug.lock */
++ hp->grab_lock = 0;
++ }
++ tell_sched_cpu_down_done(cpu);
++}
+
+ void get_online_cpus(void)
+ {
+@@ -710,10 +993,14 @@
+ struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, cpu);
+ int err;
+
++ __cpu_unplug_wait(cpu);
+ /* Park the smpboot threads */
+ kthread_park(per_cpu_ptr(&cpuhp_state, cpu)->thread);
+ smpboot_park_threads(cpu);
+
++ /* Notifiers are done. Don't let any more tasks pin this CPU. */
++ cpu_unplug_sync(cpu);
++
+ /*
+ * Prevent irq alloc/free while the dying cpu reorganizes the
+ * interrupt affinities.
+@@ -799,6 +1086,9 @@
+ struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, cpu);
+ int prev_state, ret = 0;
+ bool hasdied = false;
++ int mycpu;
++ cpumask_var_t cpumask;
++ cpumask_var_t cpumask_org;
+
+ if (num_online_cpus() == 1)
+ return -EBUSY;
+@@ -806,7 +1096,34 @@
+ if (!cpu_present(cpu))
+ return -EINVAL;
+
++ /* Move the downtaker off the unplug cpu */
++ if (!alloc_cpumask_var(&cpumask, GFP_KERNEL))
++ return -ENOMEM;
++ if (!alloc_cpumask_var(&cpumask_org, GFP_KERNEL)) {
++ free_cpumask_var(cpumask);
++ return -ENOMEM;
++ }
++
++ cpumask_copy(cpumask_org, tsk_cpus_allowed(current));
++ cpumask_andnot(cpumask, cpu_online_mask, cpumask_of(cpu));
++ set_cpus_allowed_ptr(current, cpumask);
++ free_cpumask_var(cpumask);
++ migrate_disable();
++ mycpu = smp_processor_id();
++ if (mycpu == cpu) {
++ printk(KERN_ERR "Yuck! Still on unplug CPU\n!");
++ migrate_enable();
++ ret = -EBUSY;
++ goto restore_cpus;
++ }
++
++ migrate_enable();
+ cpu_hotplug_begin();
++ ret = cpu_unplug_begin(cpu);
++ if (ret) {
++ printk("cpu_unplug_begin(%d) failed\n", cpu);
++ goto out_cancel;
++ }
+
+ cpuhp_tasks_frozen = tasks_frozen;
+
+@@ -845,10 +1162,15 @@
+
+ hasdied = prev_state != st->state && st->state == CPUHP_OFFLINE;
+ out:
++ cpu_unplug_done(cpu);
++out_cancel:
+ cpu_hotplug_done();
+ /* This post dead nonsense must die */
+ if (!ret && hasdied)
+ cpu_notify_nofail(CPU_POST_DEAD, cpu);
++restore_cpus:
++ set_cpus_allowed_ptr(current, cpumask_org);
++ free_cpumask_var(cpumask_org);
+ return ret;
+ }
+
+diff -Nur linux-4.8.15.orig/kernel/debug/kdb/kdb_io.c linux-4.8.15/kernel/debug/kdb/kdb_io.c
+--- linux-4.8.15.orig/kernel/debug/kdb/kdb_io.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/debug/kdb/kdb_io.c 2017-01-01 17:07:16.003425149 +0100
+@@ -554,7 +554,6 @@
+ int linecount;
+ int colcount;
+ int logging, saved_loglevel = 0;
+- int saved_trap_printk;
+ int got_printf_lock = 0;
+ int retlen = 0;
+ int fnd, len;
+@@ -565,8 +564,6 @@
+ unsigned long uninitialized_var(flags);
+
+ preempt_disable();
+- saved_trap_printk = kdb_trap_printk;
+- kdb_trap_printk = 0;
+
+ /* Serialize kdb_printf if multiple cpus try to write at once.
+ * But if any cpu goes recursive in kdb, just print the output,
+@@ -855,7 +852,6 @@
+ } else {
+ __release(kdb_printf_lock);
+ }
+- kdb_trap_printk = saved_trap_printk;
+ preempt_enable();
+ return retlen;
+ }
+@@ -865,9 +861,11 @@
+ va_list ap;
+ int r;
+
++ kdb_trap_printk++;
+ va_start(ap, fmt);
+ r = vkdb_printf(KDB_MSGSRC_INTERNAL, fmt, ap);
+ va_end(ap);
++ kdb_trap_printk--;
+
+ return r;
+ }
+diff -Nur linux-4.8.15.orig/kernel/events/core.c linux-4.8.15/kernel/events/core.c
+--- linux-4.8.15.orig/kernel/events/core.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/events/core.c 2017-01-01 17:07:16.007425407 +0100
+@@ -1042,6 +1042,7 @@
+ raw_spin_lock_init(&cpuctx->hrtimer_lock);
+ hrtimer_init(timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_PINNED);
+ timer->function = perf_mux_hrtimer_handler;
++ timer->irqsafe = 1;
+ }
+
+ static int perf_mux_hrtimer_restart(struct perf_cpu_context *cpuctx)
+@@ -8217,6 +8218,7 @@
+
+ hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+ hwc->hrtimer.function = perf_swevent_hrtimer;
++ hwc->hrtimer.irqsafe = 1;
+
+ /*
+ * Since hrtimers have a fixed rate, we can do a static freq->period
+diff -Nur linux-4.8.15.orig/kernel/exit.c linux-4.8.15/kernel/exit.c
+--- linux-4.8.15.orig/kernel/exit.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/exit.c 2017-01-01 17:07:16.011425679 +0100
+@@ -143,7 +143,7 @@
+ * Do this under ->siglock, we can race with another thread
+ * doing sigqueue_free() if we have SIGQUEUE_PREALLOC signals.
+ */
+- flush_sigqueue(&tsk->pending);
++ flush_task_sigqueue(tsk);
+ tsk->sighand = NULL;
+ spin_unlock(&sighand->siglock);
+
+diff -Nur linux-4.8.15.orig/kernel/fork.c linux-4.8.15/kernel/fork.c
+--- linux-4.8.15.orig/kernel/fork.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/fork.c 2017-01-01 17:07:16.011425679 +0100
+@@ -251,7 +251,9 @@
+ if (atomic_dec_and_test(&sig->sigcnt))
+ free_signal_struct(sig);
+ }
+-
++#ifdef CONFIG_PREEMPT_RT_BASE
++static
++#endif
+ void __put_task_struct(struct task_struct *tsk)
+ {
+ WARN_ON(!tsk->exit_state);
+@@ -268,7 +270,18 @@
+ if (!profile_handoff_task(tsk))
+ free_task(tsk);
+ }
++#ifndef CONFIG_PREEMPT_RT_BASE
+ EXPORT_SYMBOL_GPL(__put_task_struct);
++#else
++void __put_task_struct_cb(struct rcu_head *rhp)
++{
++ struct task_struct *tsk = container_of(rhp, struct task_struct, put_rcu);
++
++ __put_task_struct(tsk);
++
++}
++EXPORT_SYMBOL_GPL(__put_task_struct_cb);
++#endif
+
+ void __init __weak arch_task_cache_init(void) { }
+
+@@ -702,6 +715,19 @@
+ }
+ EXPORT_SYMBOL_GPL(__mmdrop);
+
++#ifdef CONFIG_PREEMPT_RT_BASE
++/*
++ * RCU callback for delayed mm drop. Not strictly rcu, but we don't
++ * want another facility to make this work.
++ */
++void __mmdrop_delayed(struct rcu_head *rhp)
++{
++ struct mm_struct *mm = container_of(rhp, struct mm_struct, delayed_drop);
++
++ __mmdrop(mm);
++}
++#endif
++
+ static inline void __mmput(struct mm_struct *mm)
+ {
+ VM_BUG_ON(atomic_read(&mm->mm_users));
+@@ -1274,6 +1300,9 @@
+ */
+ static void posix_cpu_timers_init(struct task_struct *tsk)
+ {
++#ifdef CONFIG_PREEMPT_RT_BASE
++ tsk->posix_timer_list = NULL;
++#endif
+ tsk->cputime_expires.prof_exp = 0;
+ tsk->cputime_expires.virt_exp = 0;
+ tsk->cputime_expires.sched_exp = 0;
+@@ -1399,6 +1428,7 @@
+ spin_lock_init(&p->alloc_lock);
+
+ init_sigpending(&p->pending);
++ p->sigqueue_cache = NULL;
+
+ p->utime = p->stime = p->gtime = 0;
+ p->utimescaled = p->stimescaled = 0;
+diff -Nur linux-4.8.15.orig/kernel/futex.c linux-4.8.15/kernel/futex.c
+--- linux-4.8.15.orig/kernel/futex.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/futex.c 2017-01-01 17:07:16.015425924 +0100
+@@ -895,7 +895,9 @@
+ * task still owns the PI-state:
+ */
+ if (head->next != next) {
++ raw_spin_unlock_irq(&curr->pi_lock);
+ spin_unlock(&hb->lock);
++ raw_spin_lock_irq(&curr->pi_lock);
+ continue;
+ }
+
+@@ -1290,6 +1292,7 @@
+ struct futex_pi_state *pi_state = this->pi_state;
+ u32 uninitialized_var(curval), newval;
+ WAKE_Q(wake_q);
++ WAKE_Q(wake_sleeper_q);
+ bool deboost;
+ int ret = 0;
+
+@@ -1356,7 +1359,8 @@
+
+ raw_spin_unlock_irq(&pi_state->pi_mutex.wait_lock);
+
+- deboost = rt_mutex_futex_unlock(&pi_state->pi_mutex, &wake_q);
++ deboost = rt_mutex_futex_unlock(&pi_state->pi_mutex, &wake_q,
++ &wake_sleeper_q);
+
+ /*
+ * First unlock HB so the waiter does not spin on it once he got woken
+@@ -1364,8 +1368,9 @@
+ * deboost first (and lose our higher priority), then the task might get
+ * scheduled away before the wake up can take place.
+ */
+- spin_unlock(&hb->lock);
++ deboost |= spin_unlock_no_deboost(&hb->lock);
+ wake_up_q(&wake_q);
++ wake_up_q_sleeper(&wake_sleeper_q);
+ if (deboost)
+ rt_mutex_adjust_prio(current);
+
+@@ -1915,6 +1920,16 @@
+ requeue_pi_wake_futex(this, &key2, hb2);
+ drop_count++;
+ continue;
++ } else if (ret == -EAGAIN) {
++ /*
++ * Waiter was woken by timeout or
++ * signal and has set pi_blocked_on to
++ * PI_WAKEUP_INPROGRESS before we
++ * tried to enqueue it on the rtmutex.
++ */
++ this->pi_state = NULL;
++ put_pi_state(pi_state);
++ continue;
+ } else if (ret) {
+ /*
+ * rt_mutex_start_proxy_lock() detected a
+@@ -2805,7 +2820,7 @@
+ struct hrtimer_sleeper timeout, *to = NULL;
+ struct rt_mutex_waiter rt_waiter;
+ struct rt_mutex *pi_mutex = NULL;
+- struct futex_hash_bucket *hb;
++ struct futex_hash_bucket *hb, *hb2;
+ union futex_key key2 = FUTEX_KEY_INIT;
+ struct futex_q q = futex_q_init;
+ int res, ret;
+@@ -2830,10 +2845,7 @@
+ * The waiter is allocated on our stack, manipulated by the requeue
+ * code while we sleep on uaddr.
+ */
+- debug_rt_mutex_init_waiter(&rt_waiter);
+- RB_CLEAR_NODE(&rt_waiter.pi_tree_entry);
+- RB_CLEAR_NODE(&rt_waiter.tree_entry);
+- rt_waiter.task = NULL;
++ rt_mutex_init_waiter(&rt_waiter, false);
+
+ ret = get_futex_key(uaddr2, flags & FLAGS_SHARED, &key2, VERIFY_WRITE);
+ if (unlikely(ret != 0))
+@@ -2864,20 +2876,55 @@
+ /* Queue the futex_q, drop the hb lock, wait for wakeup. */
+ futex_wait_queue_me(hb, &q, to);
+
+- spin_lock(&hb->lock);
+- ret = handle_early_requeue_pi_wakeup(hb, &q, &key2, to);
+- spin_unlock(&hb->lock);
+- if (ret)
+- goto out_put_keys;
++ /*
++ * On RT we must avoid races with requeue and trying to block
++ * on two mutexes (hb->lock and uaddr2's rtmutex) by
++ * serializing access to pi_blocked_on with pi_lock.
++ */
++ raw_spin_lock_irq(&current->pi_lock);
++ if (current->pi_blocked_on) {
++ /*
++ * We have been requeued or are in the process of
++ * being requeued.
++ */
++ raw_spin_unlock_irq(&current->pi_lock);
++ } else {
++ /*
++ * Setting pi_blocked_on to PI_WAKEUP_INPROGRESS
++ * prevents a concurrent requeue from moving us to the
++ * uaddr2 rtmutex. After that we can safely acquire
++ * (and possibly block on) hb->lock.
++ */
++ current->pi_blocked_on = PI_WAKEUP_INPROGRESS;
++ raw_spin_unlock_irq(&current->pi_lock);
++
++ spin_lock(&hb->lock);
++
++ /*
++ * Clean up pi_blocked_on. We might leak it otherwise
++ * when we succeeded with the hb->lock in the fast
++ * path.
++ */
++ raw_spin_lock_irq(&current->pi_lock);
++ current->pi_blocked_on = NULL;
++ raw_spin_unlock_irq(&current->pi_lock);
++
++ ret = handle_early_requeue_pi_wakeup(hb, &q, &key2, to);
++ spin_unlock(&hb->lock);
++ if (ret)
++ goto out_put_keys;
++ }
+
+ /*
+- * In order for us to be here, we know our q.key == key2, and since
+- * we took the hb->lock above, we also know that futex_requeue() has
+- * completed and we no longer have to concern ourselves with a wakeup
+- * race with the atomic proxy lock acquisition by the requeue code. The
+- * futex_requeue dropped our key1 reference and incremented our key2
+- * reference count.
++ * In order to be here, we have either been requeued, are in
++ * the process of being requeued, or requeue successfully
++ * acquired uaddr2 on our behalf. If pi_blocked_on was
++ * non-null above, we may be racing with a requeue. Do not
++ * rely on q->lock_ptr to be hb2->lock until after blocking on
++ * hb->lock or hb2->lock. The futex_requeue dropped our key1
++ * reference and incremented our key2 reference count.
+ */
++ hb2 = hash_futex(&key2);
+
+ /* Check if the requeue code acquired the second futex for us. */
+ if (!q.rt_waiter) {
+@@ -2886,14 +2933,15 @@
+ * did a lock-steal - fix up the PI-state in that case.
+ */
+ if (q.pi_state && (q.pi_state->owner != current)) {
+- spin_lock(q.lock_ptr);
++ spin_lock(&hb2->lock);
++ BUG_ON(&hb2->lock != q.lock_ptr);
+ ret = fixup_pi_state_owner(uaddr2, &q, current);
+ /*
+ * Drop the reference to the pi state which
+ * the requeue_pi() code acquired for us.
+ */
+ put_pi_state(q.pi_state);
+- spin_unlock(q.lock_ptr);
++ spin_unlock(&hb2->lock);
+ }
+ } else {
+ /*
+@@ -2906,7 +2954,8 @@
+ ret = rt_mutex_finish_proxy_lock(pi_mutex, to, &rt_waiter);
+ debug_rt_mutex_free_waiter(&rt_waiter);
+
+- spin_lock(q.lock_ptr);
++ spin_lock(&hb2->lock);
++ BUG_ON(&hb2->lock != q.lock_ptr);
+ /*
+ * Fixup the pi_state owner and possibly acquire the lock if we
+ * haven't already.
+diff -Nur linux-4.8.15.orig/kernel/irq/handle.c linux-4.8.15/kernel/irq/handle.c
+--- linux-4.8.15.orig/kernel/irq/handle.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/irq/handle.c 2017-01-01 17:07:16.015425924 +0100
+@@ -181,10 +181,16 @@
+ {
+ irqreturn_t retval;
+ unsigned int flags = 0;
++ struct pt_regs *regs = get_irq_regs();
++ u64 ip = regs ? instruction_pointer(regs) : 0;
+
+ retval = __handle_irq_event_percpu(desc, &flags);
+
+- add_interrupt_randomness(desc->irq_data.irq, flags);
++#ifdef CONFIG_PREEMPT_RT_FULL
++ desc->random_ip = ip;
++#else
++ add_interrupt_randomness(desc->irq_data.irq, flags, ip);
++#endif
+
+ if (!noirqdebug)
+ note_interrupt(desc, retval);
+diff -Nur linux-4.8.15.orig/kernel/irq/manage.c linux-4.8.15/kernel/irq/manage.c
+--- linux-4.8.15.orig/kernel/irq/manage.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/irq/manage.c 2017-01-01 17:07:16.015425924 +0100
+@@ -22,6 +22,7 @@
+ #include "internals.h"
+
+ #ifdef CONFIG_IRQ_FORCED_THREADING
++# ifndef CONFIG_PREEMPT_RT_BASE
+ __read_mostly bool force_irqthreads;
+
+ static int __init setup_forced_irqthreads(char *arg)
+@@ -30,6 +31,7 @@
+ return 0;
+ }
+ early_param("threadirqs", setup_forced_irqthreads);
++# endif
+ #endif
+
+ static void __synchronize_hardirq(struct irq_desc *desc)
+@@ -233,7 +235,12 @@
+
+ if (desc->affinity_notify) {
+ kref_get(&desc->affinity_notify->kref);
++
++#ifdef CONFIG_PREEMPT_RT_BASE
++ swork_queue(&desc->affinity_notify->swork);
++#else
+ schedule_work(&desc->affinity_notify->work);
++#endif
+ }
+ irqd_set(data, IRQD_AFFINITY_SET);
+
+@@ -271,10 +278,8 @@
+ }
+ EXPORT_SYMBOL_GPL(irq_set_affinity_hint);
+
+-static void irq_affinity_notify(struct work_struct *work)
++static void _irq_affinity_notify(struct irq_affinity_notify *notify)
+ {
+- struct irq_affinity_notify *notify =
+- container_of(work, struct irq_affinity_notify, work);
+ struct irq_desc *desc = irq_to_desc(notify->irq);
+ cpumask_var_t cpumask;
+ unsigned long flags;
+@@ -296,6 +301,35 @@
+ kref_put(&notify->kref, notify->release);
+ }
+
++#ifdef CONFIG_PREEMPT_RT_BASE
++static void init_helper_thread(void)
++{
++ static int init_sworker_once;
++
++ if (init_sworker_once)
++ return;
++ if (WARN_ON(swork_get()))
++ return;
++ init_sworker_once = 1;
++}
++
++static void irq_affinity_notify(struct swork_event *swork)
++{
++ struct irq_affinity_notify *notify =
++ container_of(swork, struct irq_affinity_notify, swork);
++ _irq_affinity_notify(notify);
++}
++
++#else
++
++static void irq_affinity_notify(struct work_struct *work)
++{
++ struct irq_affinity_notify *notify =
++ container_of(work, struct irq_affinity_notify, work);
++ _irq_affinity_notify(notify);
++}
++#endif
++
+ /**
+ * irq_set_affinity_notifier - control notification of IRQ affinity changes
+ * @irq: Interrupt for which to enable/disable notification
+@@ -324,7 +358,12 @@
+ if (notify) {
+ notify->irq = irq;
+ kref_init(&notify->kref);
++#ifdef CONFIG_PREEMPT_RT_BASE
++ INIT_SWORK(&notify->swork, irq_affinity_notify);
++ init_helper_thread();
++#else
+ INIT_WORK(&notify->work, irq_affinity_notify);
++#endif
+ }
+
+ raw_spin_lock_irqsave(&desc->lock, flags);
+@@ -879,7 +918,15 @@
+ local_bh_disable();
+ ret = action->thread_fn(action->irq, action->dev_id);
+ irq_finalize_oneshot(desc, action);
+- local_bh_enable();
++ /*
++ * Interrupts which have real time requirements can be set up
++ * to avoid softirq processing in the thread handler. This is
++ * safe as these interrupts do not raise soft interrupts.
++ */
++ if (irq_settings_no_softirq_call(desc))
++ _local_bh_enable();
++ else
++ local_bh_enable();
+ return ret;
+ }
+
+@@ -976,6 +1023,12 @@
+ if (action_ret == IRQ_WAKE_THREAD)
+ irq_wake_secondary(desc, action);
+
++#ifdef CONFIG_PREEMPT_RT_FULL
++ migrate_disable();
++ add_interrupt_randomness(action->irq, 0,
++ desc->random_ip ^ (unsigned long) action);
++ migrate_enable();
++#endif
+ wake_threads_waitq(desc);
+ }
+
+@@ -1336,6 +1389,9 @@
+ irqd_set(&desc->irq_data, IRQD_NO_BALANCING);
+ }
+
++ if (new->flags & IRQF_NO_SOFTIRQ_CALL)
++ irq_settings_set_no_softirq_call(desc);
++
+ /* Set default affinity mask once everything is setup */
+ setup_affinity(desc, mask);
+
+@@ -2061,7 +2117,7 @@
+ * This call sets the internal irqchip state of an interrupt,
+ * depending on the value of @which.
+ *
+- * This function should be called with preemption disabled if the
++ * This function should be called with migration disabled if the
+ * interrupt controller has per-cpu registers.
+ */
+ int irq_set_irqchip_state(unsigned int irq, enum irqchip_irq_state which,
+diff -Nur linux-4.8.15.orig/kernel/irq/settings.h linux-4.8.15/kernel/irq/settings.h
+--- linux-4.8.15.orig/kernel/irq/settings.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/irq/settings.h 2017-01-01 17:07:16.015425924 +0100
+@@ -16,6 +16,7 @@
+ _IRQ_PER_CPU_DEVID = IRQ_PER_CPU_DEVID,
+ _IRQ_IS_POLLED = IRQ_IS_POLLED,
+ _IRQ_DISABLE_UNLAZY = IRQ_DISABLE_UNLAZY,
++ _IRQ_NO_SOFTIRQ_CALL = IRQ_NO_SOFTIRQ_CALL,
+ _IRQF_MODIFY_MASK = IRQF_MODIFY_MASK,
+ };
+
+@@ -30,6 +31,7 @@
+ #define IRQ_PER_CPU_DEVID GOT_YOU_MORON
+ #define IRQ_IS_POLLED GOT_YOU_MORON
+ #define IRQ_DISABLE_UNLAZY GOT_YOU_MORON
++#define IRQ_NO_SOFTIRQ_CALL GOT_YOU_MORON
+ #undef IRQF_MODIFY_MASK
+ #define IRQF_MODIFY_MASK GOT_YOU_MORON
+
+@@ -40,6 +42,16 @@
+ desc->status_use_accessors |= (set & _IRQF_MODIFY_MASK);
+ }
+
++static inline bool irq_settings_no_softirq_call(struct irq_desc *desc)
++{
++ return desc->status_use_accessors & _IRQ_NO_SOFTIRQ_CALL;
++}
++
++static inline void irq_settings_set_no_softirq_call(struct irq_desc *desc)
++{
++ desc->status_use_accessors |= _IRQ_NO_SOFTIRQ_CALL;
++}
++
+ static inline bool irq_settings_is_per_cpu(struct irq_desc *desc)
+ {
+ return desc->status_use_accessors & _IRQ_PER_CPU;
+diff -Nur linux-4.8.15.orig/kernel/irq/spurious.c linux-4.8.15/kernel/irq/spurious.c
+--- linux-4.8.15.orig/kernel/irq/spurious.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/irq/spurious.c 2017-01-01 17:07:16.015425924 +0100
+@@ -442,6 +442,10 @@
+
+ static int __init irqfixup_setup(char *str)
+ {
++#ifdef CONFIG_PREEMPT_RT_BASE
++ pr_warn("irqfixup boot option not supported w/ CONFIG_PREEMPT_RT_BASE\n");
++ return 1;
++#endif
+ irqfixup = 1;
+ printk(KERN_WARNING "Misrouted IRQ fixup support enabled.\n");
+ printk(KERN_WARNING "This may impact system performance.\n");
+@@ -454,6 +458,10 @@
+
+ static int __init irqpoll_setup(char *str)
+ {
++#ifdef CONFIG_PREEMPT_RT_BASE
++ pr_warn("irqpoll boot option not supported w/ CONFIG_PREEMPT_RT_BASE\n");
++ return 1;
++#endif
+ irqfixup = 2;
+ printk(KERN_WARNING "Misrouted IRQ fixup and polling support "
+ "enabled\n");
+diff -Nur linux-4.8.15.orig/kernel/irq_work.c linux-4.8.15/kernel/irq_work.c
+--- linux-4.8.15.orig/kernel/irq_work.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/irq_work.c 2017-01-01 17:07:16.019426176 +0100
+@@ -17,6 +17,7 @@
+ #include <linux/cpu.h>
+ #include <linux/notifier.h>
+ #include <linux/smp.h>
++#include <linux/interrupt.h>
+ #include <asm/processor.h>
+
+
+@@ -65,6 +66,8 @@
+ */
+ bool irq_work_queue_on(struct irq_work *work, int cpu)
+ {
++ struct llist_head *list;
++
+ /* All work should have been flushed before going offline */
+ WARN_ON_ONCE(cpu_is_offline(cpu));
+
+@@ -75,7 +78,12 @@
+ if (!irq_work_claim(work))
+ return false;
+
+- if (llist_add(&work->llnode, &per_cpu(raised_list, cpu)))
++ if (IS_ENABLED(CONFIG_PREEMPT_RT_FULL) && !(work->flags & IRQ_WORK_HARD_IRQ))
++ list = &per_cpu(lazy_list, cpu);
++ else
++ list = &per_cpu(raised_list, cpu);
++
++ if (llist_add(&work->llnode, list))
+ arch_send_call_function_single_ipi(cpu);
+
+ return true;
+@@ -86,6 +94,9 @@
+ /* Enqueue the irq work @work on the current CPU */
+ bool irq_work_queue(struct irq_work *work)
+ {
++ struct llist_head *list;
++ bool lazy_work, realtime = IS_ENABLED(CONFIG_PREEMPT_RT_FULL);
++
+ /* Only queue if not already pending */
+ if (!irq_work_claim(work))
+ return false;
+@@ -93,13 +104,15 @@
+ /* Queue the entry and raise the IPI if needed. */
+ preempt_disable();
+
+- /* If the work is "lazy", handle it from next tick if any */
+- if (work->flags & IRQ_WORK_LAZY) {
+- if (llist_add(&work->llnode, this_cpu_ptr(&lazy_list)) &&
+- tick_nohz_tick_stopped())
+- arch_irq_work_raise();
+- } else {
+- if (llist_add(&work->llnode, this_cpu_ptr(&raised_list)))
++ lazy_work = work->flags & IRQ_WORK_LAZY;
++
++ if (lazy_work || (realtime && !(work->flags & IRQ_WORK_HARD_IRQ)))
++ list = this_cpu_ptr(&lazy_list);
++ else
++ list = this_cpu_ptr(&raised_list);
++
++ if (llist_add(&work->llnode, list)) {
++ if (!lazy_work || tick_nohz_tick_stopped())
+ arch_irq_work_raise();
+ }
+
+@@ -116,9 +129,8 @@
+ raised = this_cpu_ptr(&raised_list);
+ lazy = this_cpu_ptr(&lazy_list);
+
+- if (llist_empty(raised) || arch_irq_work_has_interrupt())
+- if (llist_empty(lazy))
+- return false;
++ if (llist_empty(raised) && llist_empty(lazy))
++ return false;
+
+ /* All work should have been flushed before going offline */
+ WARN_ON_ONCE(cpu_is_offline(smp_processor_id()));
+@@ -132,7 +144,7 @@
+ struct irq_work *work;
+ struct llist_node *llnode;
+
+- BUG_ON(!irqs_disabled());
++ BUG_ON_NONRT(!irqs_disabled());
+
+ if (llist_empty(list))
+ return;
+@@ -169,7 +181,16 @@
+ void irq_work_run(void)
+ {
+ irq_work_run_list(this_cpu_ptr(&raised_list));
+- irq_work_run_list(this_cpu_ptr(&lazy_list));
++ if (IS_ENABLED(CONFIG_PREEMPT_RT_FULL)) {
++ /*
++ * NOTE: we raise softirq via IPI for safety,
++ * and execute in irq_work_tick() to move the
++ * overhead from hard to soft irq context.
++ */
++ if (!llist_empty(this_cpu_ptr(&lazy_list)))
++ raise_softirq(TIMER_SOFTIRQ);
++ } else
++ irq_work_run_list(this_cpu_ptr(&lazy_list));
+ }
+ EXPORT_SYMBOL_GPL(irq_work_run);
+
+@@ -179,8 +200,17 @@
+
+ if (!llist_empty(raised) && !arch_irq_work_has_interrupt())
+ irq_work_run_list(raised);
++
++ if (!IS_ENABLED(CONFIG_PREEMPT_RT_FULL))
++ irq_work_run_list(this_cpu_ptr(&lazy_list));
++}
++
++#if defined(CONFIG_IRQ_WORK) && defined(CONFIG_PREEMPT_RT_FULL)
++void irq_work_tick_soft(void)
++{
+ irq_work_run_list(this_cpu_ptr(&lazy_list));
+ }
++#endif
+
+ /*
+ * Synchronize against the irq_work @entry, ensures the entry is not
+diff -Nur linux-4.8.15.orig/kernel/Kconfig.locks linux-4.8.15/kernel/Kconfig.locks
+--- linux-4.8.15.orig/kernel/Kconfig.locks 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/Kconfig.locks 2017-01-01 17:07:15.995424645 +0100
+@@ -225,11 +225,11 @@
+
+ config MUTEX_SPIN_ON_OWNER
+ def_bool y
+- depends on SMP && !DEBUG_MUTEXES && ARCH_SUPPORTS_ATOMIC_RMW
++ depends on SMP && !DEBUG_MUTEXES && ARCH_SUPPORTS_ATOMIC_RMW && !PREEMPT_RT_FULL
+
+ config RWSEM_SPIN_ON_OWNER
+ def_bool y
+- depends on SMP && RWSEM_XCHGADD_ALGORITHM && ARCH_SUPPORTS_ATOMIC_RMW
++ depends on SMP && RWSEM_XCHGADD_ALGORITHM && ARCH_SUPPORTS_ATOMIC_RMW && !PREEMPT_RT_FULL
+
+ config LOCK_SPIN_ON_OWNER
+ def_bool y
+diff -Nur linux-4.8.15.orig/kernel/Kconfig.preempt linux-4.8.15/kernel/Kconfig.preempt
+--- linux-4.8.15.orig/kernel/Kconfig.preempt 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/Kconfig.preempt 2017-01-01 17:07:15.995424645 +0100
+@@ -1,3 +1,16 @@
++config PREEMPT
++ bool
++ select PREEMPT_COUNT
++
++config PREEMPT_RT_BASE
++ bool
++ select PREEMPT
++
++config HAVE_PREEMPT_LAZY
++ bool
++
++config PREEMPT_LAZY
++ def_bool y if HAVE_PREEMPT_LAZY && PREEMPT_RT_FULL
+
+ choice
+ prompt "Preemption Model"
+@@ -33,9 +46,9 @@
+
+ Select this if you are building a kernel for a desktop system.
+
+-config PREEMPT
++config PREEMPT__LL
+ bool "Preemptible Kernel (Low-Latency Desktop)"
+- select PREEMPT_COUNT
++ select PREEMPT
+ select UNINLINE_SPIN_UNLOCK if !ARCH_INLINE_SPIN_UNLOCK
+ help
+ This option reduces the latency of the kernel by making
+@@ -52,6 +65,22 @@
+ embedded system with latency requirements in the milliseconds
+ range.
+
++config PREEMPT_RTB
++ bool "Preemptible Kernel (Basic RT)"
++ select PREEMPT_RT_BASE
++ help
++ This option is basically the same as (Low-Latency Desktop) but
++ enables changes which are preliminary for the full preemptible
++ RT kernel.
++
++config PREEMPT_RT_FULL
++ bool "Fully Preemptible Kernel (RT)"
++ depends on IRQ_FORCED_THREADING
++ select PREEMPT_RT_BASE
++ select PREEMPT_RCU
++ help
++ All and everything
++
+ endchoice
+
+ config PREEMPT_COUNT
+diff -Nur linux-4.8.15.orig/kernel/ksysfs.c linux-4.8.15/kernel/ksysfs.c
+--- linux-4.8.15.orig/kernel/ksysfs.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/ksysfs.c 2017-01-01 17:07:16.019426176 +0100
+@@ -136,6 +136,15 @@
+
+ #endif /* CONFIG_KEXEC_CORE */
+
++#if defined(CONFIG_PREEMPT_RT_FULL)
++static ssize_t realtime_show(struct kobject *kobj,
++ struct kobj_attribute *attr, char *buf)
++{
++ return sprintf(buf, "%d\n", 1);
++}
++KERNEL_ATTR_RO(realtime);
++#endif
++
+ /* whether file capabilities are enabled */
+ static ssize_t fscaps_show(struct kobject *kobj,
+ struct kobj_attribute *attr, char *buf)
+@@ -225,6 +234,9 @@
+ &rcu_expedited_attr.attr,
+ &rcu_normal_attr.attr,
+ #endif
++#ifdef CONFIG_PREEMPT_RT_FULL
++ &realtime_attr.attr,
++#endif
+ NULL
+ };
+
+diff -Nur linux-4.8.15.orig/kernel/locking/lglock.c linux-4.8.15/kernel/locking/lglock.c
+--- linux-4.8.15.orig/kernel/locking/lglock.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/locking/lglock.c 2017-01-01 17:07:16.019426176 +0100
+@@ -4,6 +4,15 @@
+ #include <linux/cpu.h>
+ #include <linux/string.h>
+
++#ifndef CONFIG_PREEMPT_RT_FULL
++# define lg_lock_ptr arch_spinlock_t
++# define lg_do_lock(l) arch_spin_lock(l)
++# define lg_do_unlock(l) arch_spin_unlock(l)
++#else
++# define lg_lock_ptr struct rt_mutex
++# define lg_do_lock(l) __rt_spin_lock__no_mg(l)
++# define lg_do_unlock(l) __rt_spin_unlock(l)
++#endif
+ /*
+ * Note there is no uninit, so lglocks cannot be defined in
+ * modules (but it's fine to use them from there)
+@@ -12,51 +21,60 @@
+
+ void lg_lock_init(struct lglock *lg, char *name)
+ {
++#ifdef CONFIG_PREEMPT_RT_FULL
++ int i;
++
++ for_each_possible_cpu(i) {
++ struct rt_mutex *lock = per_cpu_ptr(lg->lock, i);
++
++ rt_mutex_init(lock);
++ }
++#endif
+ LOCKDEP_INIT_MAP(&lg->lock_dep_map, name, &lg->lock_key, 0);
+ }
+ EXPORT_SYMBOL(lg_lock_init);
+
+ void lg_local_lock(struct lglock *lg)
+ {
+- arch_spinlock_t *lock;
++ lg_lock_ptr *lock;
+
+- preempt_disable();
++ migrate_disable();
+ lock_acquire_shared(&lg->lock_dep_map, 0, 0, NULL, _RET_IP_);
+ lock = this_cpu_ptr(lg->lock);
+- arch_spin_lock(lock);
++ lg_do_lock(lock);
+ }
+ EXPORT_SYMBOL(lg_local_lock);
+
+ void lg_local_unlock(struct lglock *lg)
+ {
+- arch_spinlock_t *lock;
++ lg_lock_ptr *lock;
+
+ lock_release(&lg->lock_dep_map, 1, _RET_IP_);
+ lock = this_cpu_ptr(lg->lock);
+- arch_spin_unlock(lock);
+- preempt_enable();
++ lg_do_unlock(lock);
++ migrate_enable();
+ }
+ EXPORT_SYMBOL(lg_local_unlock);
+
+ void lg_local_lock_cpu(struct lglock *lg, int cpu)
+ {
+- arch_spinlock_t *lock;
++ lg_lock_ptr *lock;
+
+- preempt_disable();
++ preempt_disable_nort();
+ lock_acquire_shared(&lg->lock_dep_map, 0, 0, NULL, _RET_IP_);
+ lock = per_cpu_ptr(lg->lock, cpu);
+- arch_spin_lock(lock);
++ lg_do_lock(lock);
+ }
+ EXPORT_SYMBOL(lg_local_lock_cpu);
+
+ void lg_local_unlock_cpu(struct lglock *lg, int cpu)
+ {
+- arch_spinlock_t *lock;
++ lg_lock_ptr *lock;
+
+ lock_release(&lg->lock_dep_map, 1, _RET_IP_);
+ lock = per_cpu_ptr(lg->lock, cpu);
+- arch_spin_unlock(lock);
+- preempt_enable();
++ lg_do_unlock(lock);
++ preempt_enable_nort();
+ }
+ EXPORT_SYMBOL(lg_local_unlock_cpu);
+
+@@ -68,30 +86,30 @@
+ if (cpu2 < cpu1)
+ swap(cpu1, cpu2);
+
+- preempt_disable();
++ preempt_disable_nort();
+ lock_acquire_shared(&lg->lock_dep_map, 0, 0, NULL, _RET_IP_);
+- arch_spin_lock(per_cpu_ptr(lg->lock, cpu1));
+- arch_spin_lock(per_cpu_ptr(lg->lock, cpu2));
++ lg_do_lock(per_cpu_ptr(lg->lock, cpu1));
++ lg_do_lock(per_cpu_ptr(lg->lock, cpu2));
+ }
+
+ void lg_double_unlock(struct lglock *lg, int cpu1, int cpu2)
+ {
+ lock_release(&lg->lock_dep_map, 1, _RET_IP_);
+- arch_spin_unlock(per_cpu_ptr(lg->lock, cpu1));
+- arch_spin_unlock(per_cpu_ptr(lg->lock, cpu2));
+- preempt_enable();
++ lg_do_unlock(per_cpu_ptr(lg->lock, cpu1));
++ lg_do_unlock(per_cpu_ptr(lg->lock, cpu2));
++ preempt_enable_nort();
+ }
+
+ void lg_global_lock(struct lglock *lg)
+ {
+ int i;
+
+- preempt_disable();
++ preempt_disable_nort();
+ lock_acquire_exclusive(&lg->lock_dep_map, 0, 0, NULL, _RET_IP_);
+ for_each_possible_cpu(i) {
+- arch_spinlock_t *lock;
++ lg_lock_ptr *lock;
+ lock = per_cpu_ptr(lg->lock, i);
+- arch_spin_lock(lock);
++ lg_do_lock(lock);
+ }
+ }
+ EXPORT_SYMBOL(lg_global_lock);
+@@ -102,10 +120,35 @@
+
+ lock_release(&lg->lock_dep_map, 1, _RET_IP_);
+ for_each_possible_cpu(i) {
+- arch_spinlock_t *lock;
++ lg_lock_ptr *lock;
+ lock = per_cpu_ptr(lg->lock, i);
+- arch_spin_unlock(lock);
++ lg_do_unlock(lock);
+ }
+- preempt_enable();
++ preempt_enable_nort();
+ }
+ EXPORT_SYMBOL(lg_global_unlock);
++
++#ifdef CONFIG_PREEMPT_RT_FULL
++/*
++ * HACK: If you use this, you get to keep the pieces.
++ * Used in queue_stop_cpus_work() when stop machinery
++ * is called from inactive CPU, so we can't schedule.
++ */
++# define lg_do_trylock_relax(l) \
++ do { \
++ while (!__rt_spin_trylock(l)) \
++ cpu_relax(); \
++ } while (0)
++
++void lg_global_trylock_relax(struct lglock *lg)
++{
++ int i;
++
++ lock_acquire_exclusive(&lg->lock_dep_map, 0, 0, NULL, _RET_IP_);
++ for_each_possible_cpu(i) {
++ lg_lock_ptr *lock;
++ lock = per_cpu_ptr(lg->lock, i);
++ lg_do_trylock_relax(lock);
++ }
++}
++#endif
+diff -Nur linux-4.8.15.orig/kernel/locking/lockdep.c linux-4.8.15/kernel/locking/lockdep.c
+--- linux-4.8.15.orig/kernel/locking/lockdep.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/locking/lockdep.c 2017-01-01 17:07:16.019426176 +0100
+@@ -3686,6 +3686,7 @@
+ }
+ }
+
++#ifndef CONFIG_PREEMPT_RT_FULL
+ /*
+ * We dont accurately track softirq state in e.g.
+ * hardirq contexts (such as on 4KSTACKS), so only
+@@ -3700,6 +3701,7 @@
+ DEBUG_LOCKS_WARN_ON(!current->softirqs_enabled);
+ }
+ }
++#endif
+
+ if (!debug_locks)
+ print_irqtrace_events(current);
+diff -Nur linux-4.8.15.orig/kernel/locking/locktorture.c linux-4.8.15/kernel/locking/locktorture.c
+--- linux-4.8.15.orig/kernel/locking/locktorture.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/locking/locktorture.c 2017-01-01 17:07:16.019426176 +0100
+@@ -26,7 +26,6 @@
+ #include <linux/kthread.h>
+ #include <linux/sched/rt.h>
+ #include <linux/spinlock.h>
+-#include <linux/rwlock.h>
+ #include <linux/mutex.h>
+ #include <linux/rwsem.h>
+ #include <linux/smp.h>
+diff -Nur linux-4.8.15.orig/kernel/locking/Makefile linux-4.8.15/kernel/locking/Makefile
+--- linux-4.8.15.orig/kernel/locking/Makefile 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/locking/Makefile 2017-01-01 17:07:16.019426176 +0100
+@@ -2,7 +2,7 @@
+ # and is generally not a function of system call inputs.
+ KCOV_INSTRUMENT := n
+
+-obj-y += mutex.o semaphore.o rwsem.o percpu-rwsem.o
++obj-y += semaphore.o percpu-rwsem.o
+
+ ifdef CONFIG_FUNCTION_TRACER
+ CFLAGS_REMOVE_lockdep.o = $(CC_FLAGS_FTRACE)
+@@ -11,7 +11,11 @@
+ CFLAGS_REMOVE_rtmutex-debug.o = $(CC_FLAGS_FTRACE)
+ endif
+
++ifneq ($(CONFIG_PREEMPT_RT_FULL),y)
++obj-y += mutex.o
+ obj-$(CONFIG_DEBUG_MUTEXES) += mutex-debug.o
++obj-y += rwsem.o
++endif
+ obj-$(CONFIG_LOCKDEP) += lockdep.o
+ ifeq ($(CONFIG_PROC_FS),y)
+ obj-$(CONFIG_LOCKDEP) += lockdep_proc.o
+@@ -25,7 +29,10 @@
+ obj-$(CONFIG_DEBUG_RT_MUTEXES) += rtmutex-debug.o
+ obj-$(CONFIG_DEBUG_SPINLOCK) += spinlock.o
+ obj-$(CONFIG_DEBUG_SPINLOCK) += spinlock_debug.o
++ifneq ($(CONFIG_PREEMPT_RT_FULL),y)
+ obj-$(CONFIG_RWSEM_GENERIC_SPINLOCK) += rwsem-spinlock.o
+ obj-$(CONFIG_RWSEM_XCHGADD_ALGORITHM) += rwsem-xadd.o
++endif
++obj-$(CONFIG_PREEMPT_RT_FULL) += rt.o
+ obj-$(CONFIG_QUEUED_RWLOCKS) += qrwlock.o
+ obj-$(CONFIG_LOCK_TORTURE_TEST) += locktorture.o
+diff -Nur linux-4.8.15.orig/kernel/locking/rt.c linux-4.8.15/kernel/locking/rt.c
+--- linux-4.8.15.orig/kernel/locking/rt.c 1970-01-01 01:00:00.000000000 +0100
++++ linux-4.8.15/kernel/locking/rt.c 2017-01-01 17:07:16.019426176 +0100
+@@ -0,0 +1,498 @@
++/*
++ * kernel/rt.c
++ *
++ * Real-Time Preemption Support
++ *
++ * started by Ingo Molnar:
++ *
++ * Copyright (C) 2004-2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
++ * Copyright (C) 2006, Timesys Corp., Thomas Gleixner <tglx@timesys.com>
++ *
++ * historic credit for proving that Linux spinlocks can be implemented via
++ * RT-aware mutexes goes to many people: The Pmutex project (Dirk Grambow
++ * and others) who prototyped it on 2.4 and did lots of comparative
++ * research and analysis; TimeSys, for proving that you can implement a
++ * fully preemptible kernel via the use of IRQ threading and mutexes;
++ * Bill Huey for persuasively arguing on lkml that the mutex model is the
++ * right one; and to MontaVista, who ported pmutexes to 2.6.
++ *
++ * This code is a from-scratch implementation and is not based on pmutexes,
++ * but the idea of converting spinlocks to mutexes is used here too.
++ *
++ * lock debugging, locking tree, deadlock detection:
++ *
++ * Copyright (C) 2004, LynuxWorks, Inc., Igor Manyilov, Bill Huey
++ * Released under the General Public License (GPL).
++ *
++ * Includes portions of the generic R/W semaphore implementation from:
++ *
++ * Copyright (c) 2001 David Howells (dhowells@redhat.com).
++ * - Derived partially from idea by Andrea Arcangeli <andrea@suse.de>
++ * - Derived also from comments by Linus
++ *
++ * Pending ownership of locks and ownership stealing:
++ *
++ * Copyright (C) 2005, Kihon Technologies Inc., Steven Rostedt
++ *
++ * (also by Steven Rostedt)
++ * - Converted single pi_lock to individual task locks.
++ *
++ * By Esben Nielsen:
++ * Doing priority inheritance with help of the scheduler.
++ *
++ * Copyright (C) 2006, Timesys Corp., Thomas Gleixner <tglx@timesys.com>
++ * - major rework based on Esben Nielsens initial patch
++ * - replaced thread_info references by task_struct refs
++ * - removed task->pending_owner dependency
++ * - BKL drop/reacquire for semaphore style locks to avoid deadlocks
++ * in the scheduler return path as discussed with Steven Rostedt
++ *
++ * Copyright (C) 2006, Kihon Technologies Inc.
++ * Steven Rostedt <rostedt@goodmis.org>
++ * - debugged and patched Thomas Gleixner's rework.
++ * - added back the cmpxchg to the rework.
++ * - turned atomic require back on for SMP.
++ */
++
++#include <linux/spinlock.h>
++#include <linux/rtmutex.h>
++#include <linux/sched.h>
++#include <linux/delay.h>
++#include <linux/module.h>
++#include <linux/kallsyms.h>
++#include <linux/syscalls.h>
++#include <linux/interrupt.h>
++#include <linux/plist.h>
++#include <linux/fs.h>
++#include <linux/futex.h>
++#include <linux/hrtimer.h>
++
++#include "rtmutex_common.h"
++
++/*
++ * struct mutex functions
++ */
++void __mutex_do_init(struct mutex *mutex, const char *name,
++ struct lock_class_key *key)
++{
++#ifdef CONFIG_DEBUG_LOCK_ALLOC
++ /*
++ * Make sure we are not reinitializing a held lock:
++ */
++ debug_check_no_locks_freed((void *)mutex, sizeof(*mutex));
++ lockdep_init_map(&mutex->dep_map, name, key, 0);
++#endif
++ mutex->lock.save_state = 0;
++}
++EXPORT_SYMBOL(__mutex_do_init);
++
++void __lockfunc _mutex_lock(struct mutex *lock)
++{
++ mutex_acquire(&lock->dep_map, 0, 0, _RET_IP_);
++ rt_mutex_lock(&lock->lock);
++}
++EXPORT_SYMBOL(_mutex_lock);
++
++int __lockfunc _mutex_lock_interruptible(struct mutex *lock)
++{
++ int ret;
++
++ mutex_acquire(&lock->dep_map, 0, 0, _RET_IP_);
++ ret = rt_mutex_lock_interruptible(&lock->lock);
++ if (ret)
++ mutex_release(&lock->dep_map, 1, _RET_IP_);
++ return ret;
++}
++EXPORT_SYMBOL(_mutex_lock_interruptible);
++
++int __lockfunc _mutex_lock_killable(struct mutex *lock)
++{
++ int ret;
++
++ mutex_acquire(&lock->dep_map, 0, 0, _RET_IP_);
++ ret = rt_mutex_lock_killable(&lock->lock);
++ if (ret)
++ mutex_release(&lock->dep_map, 1, _RET_IP_);
++ return ret;
++}
++EXPORT_SYMBOL(_mutex_lock_killable);
++
++#ifdef CONFIG_DEBUG_LOCK_ALLOC
++void __lockfunc _mutex_lock_nested(struct mutex *lock, int subclass)
++{
++ mutex_acquire_nest(&lock->dep_map, subclass, 0, NULL, _RET_IP_);
++ rt_mutex_lock(&lock->lock);
++}
++EXPORT_SYMBOL(_mutex_lock_nested);
++
++void __lockfunc _mutex_lock_nest_lock(struct mutex *lock, struct lockdep_map *nest)
++{
++ mutex_acquire_nest(&lock->dep_map, 0, 0, nest, _RET_IP_);
++ rt_mutex_lock(&lock->lock);
++}
++EXPORT_SYMBOL(_mutex_lock_nest_lock);
++
++int __lockfunc _mutex_lock_interruptible_nested(struct mutex *lock, int subclass)
++{
++ int ret;
++
++ mutex_acquire_nest(&lock->dep_map, subclass, 0, NULL, _RET_IP_);
++ ret = rt_mutex_lock_interruptible(&lock->lock);
++ if (ret)
++ mutex_release(&lock->dep_map, 1, _RET_IP_);
++ return ret;
++}
++EXPORT_SYMBOL(_mutex_lock_interruptible_nested);
++
++int __lockfunc _mutex_lock_killable_nested(struct mutex *lock, int subclass)
++{
++ int ret;
++
++ mutex_acquire(&lock->dep_map, subclass, 0, _RET_IP_);
++ ret = rt_mutex_lock_killable(&lock->lock);
++ if (ret)
++ mutex_release(&lock->dep_map, 1, _RET_IP_);
++ return ret;
++}
++EXPORT_SYMBOL(_mutex_lock_killable_nested);
++#endif
++
++int __lockfunc _mutex_trylock(struct mutex *lock)
++{
++ int ret = rt_mutex_trylock(&lock->lock);
++
++ if (ret)
++ mutex_acquire(&lock->dep_map, 0, 1, _RET_IP_);
++
++ return ret;
++}
++EXPORT_SYMBOL(_mutex_trylock);
++
++void __lockfunc _mutex_unlock(struct mutex *lock)
++{
++ mutex_release(&lock->dep_map, 1, _RET_IP_);
++ rt_mutex_unlock(&lock->lock);
++}
++EXPORT_SYMBOL(_mutex_unlock);
++
++/*
++ * rwlock_t functions
++ */
++int __lockfunc rt_write_trylock(rwlock_t *rwlock)
++{
++ int ret;
++
++ migrate_disable();
++ ret = rt_mutex_trylock(&rwlock->lock);
++ if (ret)
++ rwlock_acquire(&rwlock->dep_map, 0, 1, _RET_IP_);
++ else
++ migrate_enable();
++
++ return ret;
++}
++EXPORT_SYMBOL(rt_write_trylock);
++
++int __lockfunc rt_write_trylock_irqsave(rwlock_t *rwlock, unsigned long *flags)
++{
++ int ret;
++
++ *flags = 0;
++ ret = rt_write_trylock(rwlock);
++ return ret;
++}
++EXPORT_SYMBOL(rt_write_trylock_irqsave);
++
++int __lockfunc rt_read_trylock(rwlock_t *rwlock)
++{
++ struct rt_mutex *lock = &rwlock->lock;
++ int ret = 1;
++
++ /*
++ * recursive read locks succeed when current owns the lock,
++ * but not when read_depth == 0 which means that the lock is
++ * write locked.
++ */
++ if (rt_mutex_owner(lock) != current) {
++ migrate_disable();
++ ret = rt_mutex_trylock(lock);
++ if (ret)
++ rwlock_acquire(&rwlock->dep_map, 0, 1, _RET_IP_);
++ else
++ migrate_enable();
++
++ } else if (!rwlock->read_depth) {
++ ret = 0;
++ }
++
++ if (ret)
++ rwlock->read_depth++;
++
++ return ret;
++}
++EXPORT_SYMBOL(rt_read_trylock);
++
++void __lockfunc rt_write_lock(rwlock_t *rwlock)
++{
++ rwlock_acquire(&rwlock->dep_map, 0, 0, _RET_IP_);
++ __rt_spin_lock(&rwlock->lock);
++}
++EXPORT_SYMBOL(rt_write_lock);
++
++void __lockfunc rt_read_lock(rwlock_t *rwlock)
++{
++ struct rt_mutex *lock = &rwlock->lock;
++
++
++ /*
++ * recursive read locks succeed when current owns the lock
++ */
++ if (rt_mutex_owner(lock) != current) {
++ rwlock_acquire(&rwlock->dep_map, 0, 0, _RET_IP_);
++ __rt_spin_lock(lock);
++ }
++ rwlock->read_depth++;
++}
++
++EXPORT_SYMBOL(rt_read_lock);
++
++void __lockfunc rt_write_unlock(rwlock_t *rwlock)
++{
++ /* NOTE: we always pass in '1' for nested, for simplicity */
++ rwlock_release(&rwlock->dep_map, 1, _RET_IP_);
++ __rt_spin_unlock(&rwlock->lock);
++ migrate_enable();
++}
++EXPORT_SYMBOL(rt_write_unlock);
++
++void __lockfunc rt_read_unlock(rwlock_t *rwlock)
++{
++ /* Release the lock only when read_depth is down to 0 */
++ if (--rwlock->read_depth == 0) {
++ rwlock_release(&rwlock->dep_map, 1, _RET_IP_);
++ __rt_spin_unlock(&rwlock->lock);
++ migrate_enable();
++ }
++}
++EXPORT_SYMBOL(rt_read_unlock);
++
++unsigned long __lockfunc rt_write_lock_irqsave(rwlock_t *rwlock)
++{
++ rt_write_lock(rwlock);
++
++ return 0;
++}
++EXPORT_SYMBOL(rt_write_lock_irqsave);
++
++unsigned long __lockfunc rt_read_lock_irqsave(rwlock_t *rwlock)
++{
++ rt_read_lock(rwlock);
++
++ return 0;
++}
++EXPORT_SYMBOL(rt_read_lock_irqsave);
++
++void __rt_rwlock_init(rwlock_t *rwlock, char *name, struct lock_class_key *key)
++{
++#ifdef CONFIG_DEBUG_LOCK_ALLOC
++ /*
++ * Make sure we are not reinitializing a held lock:
++ */
++ debug_check_no_locks_freed((void *)rwlock, sizeof(*rwlock));
++ lockdep_init_map(&rwlock->dep_map, name, key, 0);
++#endif
++ rwlock->lock.save_state = 1;
++ rwlock->read_depth = 0;
++}
++EXPORT_SYMBOL(__rt_rwlock_init);
++
++/*
++ * rw_semaphores
++ */
++
++void rt_up_write(struct rw_semaphore *rwsem)
++{
++ rwsem_release(&rwsem->dep_map, 1, _RET_IP_);
++ rt_mutex_unlock(&rwsem->lock);
++}
++EXPORT_SYMBOL(rt_up_write);
++
++void __rt_up_read(struct rw_semaphore *rwsem)
++{
++ if (--rwsem->read_depth == 0)
++ rt_mutex_unlock(&rwsem->lock);
++}
++
++void rt_up_read(struct rw_semaphore *rwsem)
++{
++ rwsem_release(&rwsem->dep_map, 1, _RET_IP_);
++ __rt_up_read(rwsem);
++}
++EXPORT_SYMBOL(rt_up_read);
++
++/*
++ * downgrade a write lock into a read lock
++ * - just wake up any readers at the front of the queue
++ */
++void rt_downgrade_write(struct rw_semaphore *rwsem)
++{
++ BUG_ON(rt_mutex_owner(&rwsem->lock) != current);
++ rwsem->read_depth = 1;
++}
++EXPORT_SYMBOL(rt_downgrade_write);
++
++int rt_down_write_trylock(struct rw_semaphore *rwsem)
++{
++ int ret = rt_mutex_trylock(&rwsem->lock);
++
++ if (ret)
++ rwsem_acquire(&rwsem->dep_map, 0, 1, _RET_IP_);
++ return ret;
++}
++EXPORT_SYMBOL(rt_down_write_trylock);
++
++void rt_down_write(struct rw_semaphore *rwsem)
++{
++ rwsem_acquire(&rwsem->dep_map, 0, 0, _RET_IP_);
++ rt_mutex_lock(&rwsem->lock);
++}
++EXPORT_SYMBOL(rt_down_write);
++
++int rt_down_write_killable(struct rw_semaphore *rwsem)
++{
++ int ret;
++
++ rwsem_acquire(&rwsem->dep_map, 0, 0, _RET_IP_);
++ ret = rt_mutex_lock_killable(&rwsem->lock);
++ if (ret)
++ rwsem_release(&rwsem->dep_map, 1, _RET_IP_);
++ return ret;
++}
++EXPORT_SYMBOL(rt_down_write_killable);
++
++int rt_down_write_killable_nested(struct rw_semaphore *rwsem, int subclass)
++{
++ int ret;
++
++ rwsem_acquire(&rwsem->dep_map, subclass, 0, _RET_IP_);
++ ret = rt_mutex_lock_killable(&rwsem->lock);
++ if (ret)
++ rwsem_release(&rwsem->dep_map, 1, _RET_IP_);
++ return ret;
++}
++EXPORT_SYMBOL(rt_down_write_killable_nested);
++
++void rt_down_write_nested(struct rw_semaphore *rwsem, int subclass)
++{
++ rwsem_acquire(&rwsem->dep_map, subclass, 0, _RET_IP_);
++ rt_mutex_lock(&rwsem->lock);
++}
++EXPORT_SYMBOL(rt_down_write_nested);
++
++void rt_down_write_nested_lock(struct rw_semaphore *rwsem,
++ struct lockdep_map *nest)
++{
++ rwsem_acquire_nest(&rwsem->dep_map, 0, 0, nest, _RET_IP_);
++ rt_mutex_lock(&rwsem->lock);
++}
++EXPORT_SYMBOL(rt_down_write_nested_lock);
++
++int rt__down_read_trylock(struct rw_semaphore *rwsem)
++{
++ struct rt_mutex *lock = &rwsem->lock;
++ int ret = 1;
++
++ /*
++ * recursive read locks succeed when current owns the rwsem,
++ * but not when read_depth == 0 which means that the rwsem is
++ * write locked.
++ */
++ if (rt_mutex_owner(lock) != current)
++ ret = rt_mutex_trylock(&rwsem->lock);
++ else if (!rwsem->read_depth)
++ ret = 0;
++
++ if (ret)
++ rwsem->read_depth++;
++ return ret;
++
++}
++
++int rt_down_read_trylock(struct rw_semaphore *rwsem)
++{
++ int ret;
++
++ ret = rt__down_read_trylock(rwsem);
++ if (ret)
++ rwsem_acquire(&rwsem->dep_map, 0, 1, _RET_IP_);
++
++ return ret;
++}
++EXPORT_SYMBOL(rt_down_read_trylock);
++
++void rt__down_read(struct rw_semaphore *rwsem)
++{
++ struct rt_mutex *lock = &rwsem->lock;
++
++ if (rt_mutex_owner(lock) != current)
++ rt_mutex_lock(&rwsem->lock);
++ rwsem->read_depth++;
++}
++EXPORT_SYMBOL(rt__down_read);
++
++static void __rt_down_read(struct rw_semaphore *rwsem, int subclass)
++{
++ rwsem_acquire_read(&rwsem->dep_map, subclass, 0, _RET_IP_);
++ rt__down_read(rwsem);
++}
++
++void rt_down_read(struct rw_semaphore *rwsem)
++{
++ __rt_down_read(rwsem, 0);
++}
++EXPORT_SYMBOL(rt_down_read);
++
++void rt_down_read_nested(struct rw_semaphore *rwsem, int subclass)
++{
++ __rt_down_read(rwsem, subclass);
++}
++EXPORT_SYMBOL(rt_down_read_nested);
++
++void __rt_rwsem_init(struct rw_semaphore *rwsem, const char *name,
++ struct lock_class_key *key)
++{
++#ifdef CONFIG_DEBUG_LOCK_ALLOC
++ /*
++ * Make sure we are not reinitializing a held lock:
++ */
++ debug_check_no_locks_freed((void *)rwsem, sizeof(*rwsem));
++ lockdep_init_map(&rwsem->dep_map, name, key, 0);
++#endif
++ rwsem->read_depth = 0;
++ rwsem->lock.save_state = 0;
++}
++EXPORT_SYMBOL(__rt_rwsem_init);
++
++/**
++ * atomic_dec_and_mutex_lock - return holding mutex if we dec to 0
++ * @cnt: the atomic which we are to dec
++ * @lock: the mutex to return holding if we dec to 0
++ *
++ * return true and hold lock if we dec to 0, return false otherwise
++ */
++int atomic_dec_and_mutex_lock(atomic_t *cnt, struct mutex *lock)
++{
++ /* dec if we can't possibly hit 0 */
++ if (atomic_add_unless(cnt, -1, 1))
++ return 0;
++ /* we might hit 0, so take the lock */
++ mutex_lock(lock);
++ if (!atomic_dec_and_test(cnt)) {
++ /* when we actually did the dec, we didn't hit 0 */
++ mutex_unlock(lock);
++ return 0;
++ }
++ /* we hit 0, and we hold the lock */
++ return 1;
++}
++EXPORT_SYMBOL(atomic_dec_and_mutex_lock);
+diff -Nur linux-4.8.15.orig/kernel/locking/rtmutex.c linux-4.8.15/kernel/locking/rtmutex.c
+--- linux-4.8.15.orig/kernel/locking/rtmutex.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/locking/rtmutex.c 2017-01-01 17:07:16.023426438 +0100
+@@ -7,6 +7,11 @@
+ * Copyright (C) 2005-2006 Timesys Corp., Thomas Gleixner <tglx@timesys.com>
+ * Copyright (C) 2005 Kihon Technologies Inc., Steven Rostedt
+ * Copyright (C) 2006 Esben Nielsen
++ * Adaptive Spinlocks:
++ * Copyright (C) 2008 Novell, Inc., Gregory Haskins, Sven Dietrich,
++ * and Peter Morreale,
++ * Adaptive Spinlocks simplification:
++ * Copyright (C) 2008 Red Hat, Inc., Steven Rostedt <srostedt@redhat.com>
+ *
+ * See Documentation/locking/rt-mutex-design.txt for details.
+ */
+@@ -16,6 +21,7 @@
+ #include <linux/sched/rt.h>
+ #include <linux/sched/deadline.h>
+ #include <linux/timer.h>
++#include <linux/ww_mutex.h>
+
+ #include "rtmutex_common.h"
+
+@@ -133,6 +139,12 @@
+ WRITE_ONCE(*p, owner & ~RT_MUTEX_HAS_WAITERS);
+ }
+
++static int rt_mutex_real_waiter(struct rt_mutex_waiter *waiter)
++{
++ return waiter && waiter != PI_WAKEUP_INPROGRESS &&
++ waiter != PI_REQUEUE_INPROGRESS;
++}
++
+ /*
+ * We can speed up the acquire/release, if there's no debugging state to be
+ * set up.
+@@ -414,6 +426,14 @@
+ return debug_rt_mutex_detect_deadlock(waiter, chwalk);
+ }
+
++static void rt_mutex_wake_waiter(struct rt_mutex_waiter *waiter)
++{
++ if (waiter->savestate)
++ wake_up_lock_sleeper(waiter->task);
++ else
++ wake_up_process(waiter->task);
++}
++
+ /*
+ * Max number of times we'll walk the boosting chain:
+ */
+@@ -421,7 +441,8 @@
+
+ static inline struct rt_mutex *task_blocked_on_lock(struct task_struct *p)
+ {
+- return p->pi_blocked_on ? p->pi_blocked_on->lock : NULL;
++ return rt_mutex_real_waiter(p->pi_blocked_on) ?
++ p->pi_blocked_on->lock : NULL;
+ }
+
+ /*
+@@ -557,7 +578,7 @@
+ * reached or the state of the chain has changed while we
+ * dropped the locks.
+ */
+- if (!waiter)
++ if (!rt_mutex_real_waiter(waiter))
+ goto out_unlock_pi;
+
+ /*
+@@ -719,13 +740,16 @@
+ * follow here. This is the end of the chain we are walking.
+ */
+ if (!rt_mutex_owner(lock)) {
++ struct rt_mutex_waiter *lock_top_waiter;
++
+ /*
+ * If the requeue [7] above changed the top waiter,
+ * then we need to wake the new top waiter up to try
+ * to get the lock.
+ */
+- if (prerequeue_top_waiter != rt_mutex_top_waiter(lock))
+- wake_up_process(rt_mutex_top_waiter(lock)->task);
++ lock_top_waiter = rt_mutex_top_waiter(lock);
++ if (prerequeue_top_waiter != lock_top_waiter)
++ rt_mutex_wake_waiter(lock_top_waiter);
+ raw_spin_unlock_irq(&lock->wait_lock);
+ return 0;
+ }
+@@ -818,6 +842,25 @@
+ return ret;
+ }
+
++
++#define STEAL_NORMAL 0
++#define STEAL_LATERAL 1
++
++/*
++ * Note that RT tasks are excluded from lateral-steals to prevent the
++ * introduction of an unbounded latency
++ */
++static inline int lock_is_stealable(struct task_struct *task,
++ struct task_struct *pendowner, int mode)
++{
++ if (mode == STEAL_NORMAL || rt_task(task)) {
++ if (task->prio >= pendowner->prio)
++ return 0;
++ } else if (task->prio > pendowner->prio)
++ return 0;
++ return 1;
++}
++
+ /*
+ * Try to take an rt-mutex
+ *
+@@ -828,8 +871,9 @@
+ * @waiter: The waiter that is queued to the lock's wait tree if the
+ * callsite called task_blocked_on_lock(), otherwise NULL
+ */
+-static int try_to_take_rt_mutex(struct rt_mutex *lock, struct task_struct *task,
+- struct rt_mutex_waiter *waiter)
++static int __try_to_take_rt_mutex(struct rt_mutex *lock,
++ struct task_struct *task,
++ struct rt_mutex_waiter *waiter, int mode)
+ {
+ /*
+ * Before testing whether we can acquire @lock, we set the
+@@ -866,8 +910,10 @@
+ * If waiter is not the highest priority waiter of
+ * @lock, give up.
+ */
+- if (waiter != rt_mutex_top_waiter(lock))
++ if (waiter != rt_mutex_top_waiter(lock)) {
++ /* XXX lock_is_stealable() ? */
+ return 0;
++ }
+
+ /*
+ * We can acquire the lock. Remove the waiter from the
+@@ -885,14 +931,10 @@
+ * not need to be dequeued.
+ */
+ if (rt_mutex_has_waiters(lock)) {
+- /*
+- * If @task->prio is greater than or equal to
+- * the top waiter priority (kernel view),
+- * @task lost.
+- */
+- if (task->prio >= rt_mutex_top_waiter(lock)->prio)
+- return 0;
++ struct task_struct *pown = rt_mutex_top_waiter(lock)->task;
+
++ if (task != pown && !lock_is_stealable(task, pown, mode))
++ return 0;
+ /*
+ * The current top waiter stays enqueued. We
+ * don't have to change anything in the lock
+@@ -941,6 +983,438 @@
+ return 1;
+ }
+
++#ifdef CONFIG_PREEMPT_RT_FULL
++/*
++ * preemptible spin_lock functions:
++ */
++static inline void rt_spin_lock_fastlock(struct rt_mutex *lock,
++ void (*slowfn)(struct rt_mutex *lock,
++ bool mg_off),
++ bool do_mig_dis)
++{
++ might_sleep_no_state_check();
++
++ if (do_mig_dis)
++ migrate_disable();
++
++ if (likely(rt_mutex_cmpxchg_acquire(lock, NULL, current)))
++ rt_mutex_deadlock_account_lock(lock, current);
++ else
++ slowfn(lock, do_mig_dis);
++}
++
++static inline int rt_spin_lock_fastunlock(struct rt_mutex *lock,
++ int (*slowfn)(struct rt_mutex *lock))
++{
++ if (likely(rt_mutex_cmpxchg_release(lock, current, NULL))) {
++ rt_mutex_deadlock_account_unlock(current);
++ return 0;
++ }
++ return slowfn(lock);
++}
++#ifdef CONFIG_SMP
++/*
++ * Note that owner is a speculative pointer and dereferencing relies
++ * on rcu_read_lock() and the check against the lock owner.
++ */
++static int adaptive_wait(struct rt_mutex *lock,
++ struct task_struct *owner)
++{
++ int res = 0;
++
++ rcu_read_lock();
++ for (;;) {
++ if (owner != rt_mutex_owner(lock))
++ break;
++ /*
++ * Ensure that owner->on_cpu is dereferenced _after_
++ * checking the above to be valid.
++ */
++ barrier();
++ if (!owner->on_cpu) {
++ res = 1;
++ break;
++ }
++ cpu_relax();
++ }
++ rcu_read_unlock();
++ return res;
++}
++#else
++static int adaptive_wait(struct rt_mutex *lock,
++ struct task_struct *orig_owner)
++{
++ return 1;
++}
++#endif
++
++static int task_blocks_on_rt_mutex(struct rt_mutex *lock,
++ struct rt_mutex_waiter *waiter,
++ struct task_struct *task,
++ enum rtmutex_chainwalk chwalk);
++/*
++ * Slow path lock function spin_lock style: this variant is very
++ * careful not to miss any non-lock wakeups.
++ *
++ * We store the current state under p->pi_lock in p->saved_state and
++ * the try_to_wake_up() code handles this accordingly.
++ */
++static void noinline __sched rt_spin_lock_slowlock(struct rt_mutex *lock,
++ bool mg_off)
++{
++ struct task_struct *lock_owner, *self = current;
++ struct rt_mutex_waiter waiter, *top_waiter;
++ unsigned long flags;
++ int ret;
++
++ rt_mutex_init_waiter(&waiter, true);
++
++ raw_spin_lock_irqsave(&lock->wait_lock, flags);
++
++ if (__try_to_take_rt_mutex(lock, self, NULL, STEAL_LATERAL)) {
++ raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
++ return;
++ }
++
++ BUG_ON(rt_mutex_owner(lock) == self);
++
++ /*
++ * We save whatever state the task is in and we'll restore it
++ * after acquiring the lock taking real wakeups into account
++ * as well. We are serialized via pi_lock against wakeups. See
++ * try_to_wake_up().
++ */
++ raw_spin_lock(&self->pi_lock);
++ self->saved_state = self->state;
++ __set_current_state_no_track(TASK_UNINTERRUPTIBLE);
++ raw_spin_unlock(&self->pi_lock);
++
++ ret = task_blocks_on_rt_mutex(lock, &waiter, self, RT_MUTEX_MIN_CHAINWALK);
++ BUG_ON(ret);
++
++ for (;;) {
++ /* Try to acquire the lock again. */
++ if (__try_to_take_rt_mutex(lock, self, &waiter, STEAL_LATERAL))
++ break;
++
++ top_waiter = rt_mutex_top_waiter(lock);
++ lock_owner = rt_mutex_owner(lock);
++
++ raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
++
++ debug_rt_mutex_print_deadlock(&waiter);
++
++ if (top_waiter != &waiter || adaptive_wait(lock, lock_owner)) {
++ if (mg_off)
++ migrate_enable();
++ schedule();
++ if (mg_off)
++ migrate_disable();
++ }
++
++ raw_spin_lock_irqsave(&lock->wait_lock, flags);
++
++ raw_spin_lock(&self->pi_lock);
++ __set_current_state_no_track(TASK_UNINTERRUPTIBLE);
++ raw_spin_unlock(&self->pi_lock);
++ }
++
++ /*
++ * Restore the task state to current->saved_state. We set it
++ * to the original state above and the try_to_wake_up() code
++ * has possibly updated it when a real (non-rtmutex) wakeup
++ * happened while we were blocked. Clear saved_state so
++ * try_to_wakeup() does not get confused.
++ */
++ raw_spin_lock(&self->pi_lock);
++ __set_current_state_no_track(self->saved_state);
++ self->saved_state = TASK_RUNNING;
++ raw_spin_unlock(&self->pi_lock);
++
++ /*
++ * try_to_take_rt_mutex() sets the waiter bit
++ * unconditionally. We might have to fix that up:
++ */
++ fixup_rt_mutex_waiters(lock);
++
++ BUG_ON(rt_mutex_has_waiters(lock) && &waiter == rt_mutex_top_waiter(lock));
++ BUG_ON(!RB_EMPTY_NODE(&waiter.tree_entry));
++
++ raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
++
++ debug_rt_mutex_free_waiter(&waiter);
++}
++
++static void mark_wakeup_next_waiter(struct wake_q_head *wake_q,
++ struct wake_q_head *wake_sleeper_q,
++ struct rt_mutex *lock);
++/*
++ * Slow path to release a rt_mutex spin_lock style
++ */
++static int noinline __sched rt_spin_lock_slowunlock(struct rt_mutex *lock)
++{
++ unsigned long flags;
++ WAKE_Q(wake_q);
++ WAKE_Q(wake_sleeper_q);
++
++ raw_spin_lock_irqsave(&lock->wait_lock, flags);
++
++ debug_rt_mutex_unlock(lock);
++
++ rt_mutex_deadlock_account_unlock(current);
++
++ if (!rt_mutex_has_waiters(lock)) {
++ lock->owner = NULL;
++ raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
++ return 0;
++ }
++
++ mark_wakeup_next_waiter(&wake_q, &wake_sleeper_q, lock);
++
++ raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
++ wake_up_q(&wake_q);
++ wake_up_q_sleeper(&wake_sleeper_q);
++
++ /* Undo pi boosting.when necessary */
++ rt_mutex_adjust_prio(current);
++ return 0;
++}
++
++static int noinline __sched rt_spin_lock_slowunlock_no_deboost(struct rt_mutex *lock)
++{
++ unsigned long flags;
++ WAKE_Q(wake_q);
++ WAKE_Q(wake_sleeper_q);
++
++ raw_spin_lock_irqsave(&lock->wait_lock, flags);
++
++ debug_rt_mutex_unlock(lock);
++
++ rt_mutex_deadlock_account_unlock(current);
++
++ if (!rt_mutex_has_waiters(lock)) {
++ lock->owner = NULL;
++ raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
++ return 0;
++ }
++
++ mark_wakeup_next_waiter(&wake_q, &wake_sleeper_q, lock);
++
++ raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
++ wake_up_q(&wake_q);
++ wake_up_q_sleeper(&wake_sleeper_q);
++ return 1;
++}
++
++void __lockfunc rt_spin_lock__no_mg(spinlock_t *lock)
++{
++ rt_spin_lock_fastlock(&lock->lock, rt_spin_lock_slowlock, false);
++ spin_acquire(&lock->dep_map, 0, 0, _RET_IP_);
++}
++EXPORT_SYMBOL(rt_spin_lock__no_mg);
++
++void __lockfunc rt_spin_lock(spinlock_t *lock)
++{
++ rt_spin_lock_fastlock(&lock->lock, rt_spin_lock_slowlock, true);
++ spin_acquire(&lock->dep_map, 0, 0, _RET_IP_);
++}
++EXPORT_SYMBOL(rt_spin_lock);
++
++void __lockfunc __rt_spin_lock(struct rt_mutex *lock)
++{
++ rt_spin_lock_fastlock(lock, rt_spin_lock_slowlock, true);
++}
++EXPORT_SYMBOL(__rt_spin_lock);
++
++void __lockfunc __rt_spin_lock__no_mg(struct rt_mutex *lock)
++{
++ rt_spin_lock_fastlock(lock, rt_spin_lock_slowlock, false);
++}
++EXPORT_SYMBOL(__rt_spin_lock__no_mg);
++
++#ifdef CONFIG_DEBUG_LOCK_ALLOC
++void __lockfunc rt_spin_lock_nested(spinlock_t *lock, int subclass)
++{
++ spin_acquire(&lock->dep_map, subclass, 0, _RET_IP_);
++ rt_spin_lock_fastlock(&lock->lock, rt_spin_lock_slowlock, true);
++}
++EXPORT_SYMBOL(rt_spin_lock_nested);
++#endif
++
++void __lockfunc rt_spin_unlock__no_mg(spinlock_t *lock)
++{
++ /* NOTE: we always pass in '1' for nested, for simplicity */
++ spin_release(&lock->dep_map, 1, _RET_IP_);
++ rt_spin_lock_fastunlock(&lock->lock, rt_spin_lock_slowunlock);
++}
++EXPORT_SYMBOL(rt_spin_unlock__no_mg);
++
++void __lockfunc rt_spin_unlock(spinlock_t *lock)
++{
++ /* NOTE: we always pass in '1' for nested, for simplicity */
++ spin_release(&lock->dep_map, 1, _RET_IP_);
++ rt_spin_lock_fastunlock(&lock->lock, rt_spin_lock_slowunlock);
++ migrate_enable();
++}
++EXPORT_SYMBOL(rt_spin_unlock);
++
++int __lockfunc rt_spin_unlock_no_deboost(spinlock_t *lock)
++{
++ int ret;
++
++ /* NOTE: we always pass in '1' for nested, for simplicity */
++ spin_release(&lock->dep_map, 1, _RET_IP_);
++ ret = rt_spin_lock_fastunlock(&lock->lock, rt_spin_lock_slowunlock_no_deboost);
++ migrate_enable();
++ return ret;
++}
++
++void __lockfunc __rt_spin_unlock(struct rt_mutex *lock)
++{
++ rt_spin_lock_fastunlock(lock, rt_spin_lock_slowunlock);
++}
++EXPORT_SYMBOL(__rt_spin_unlock);
++
++/*
++ * Wait for the lock to get unlocked: instead of polling for an unlock
++ * (like raw spinlocks do), we lock and unlock, to force the kernel to
++ * schedule if there's contention:
++ */
++void __lockfunc rt_spin_unlock_wait(spinlock_t *lock)
++{
++ spin_lock(lock);
++ spin_unlock(lock);
++}
++EXPORT_SYMBOL(rt_spin_unlock_wait);
++
++int __lockfunc __rt_spin_trylock(struct rt_mutex *lock)
++{
++ return rt_mutex_trylock(lock);
++}
++
++int __lockfunc rt_spin_trylock__no_mg(spinlock_t *lock)
++{
++ int ret;
++
++ ret = rt_mutex_trylock(&lock->lock);
++ if (ret)
++ spin_acquire(&lock->dep_map, 0, 1, _RET_IP_);
++ return ret;
++}
++EXPORT_SYMBOL(rt_spin_trylock__no_mg);
++
++int __lockfunc rt_spin_trylock(spinlock_t *lock)
++{
++ int ret;
++
++ migrate_disable();
++ ret = rt_mutex_trylock(&lock->lock);
++ if (ret)
++ spin_acquire(&lock->dep_map, 0, 1, _RET_IP_);
++ else
++ migrate_enable();
++ return ret;
++}
++EXPORT_SYMBOL(rt_spin_trylock);
++
++int __lockfunc rt_spin_trylock_bh(spinlock_t *lock)
++{
++ int ret;
++
++ local_bh_disable();
++ ret = rt_mutex_trylock(&lock->lock);
++ if (ret) {
++ migrate_disable();
++ spin_acquire(&lock->dep_map, 0, 1, _RET_IP_);
++ } else
++ local_bh_enable();
++ return ret;
++}
++EXPORT_SYMBOL(rt_spin_trylock_bh);
++
++int __lockfunc rt_spin_trylock_irqsave(spinlock_t *lock, unsigned long *flags)
++{
++ int ret;
++
++ *flags = 0;
++ ret = rt_mutex_trylock(&lock->lock);
++ if (ret) {
++ migrate_disable();
++ spin_acquire(&lock->dep_map, 0, 1, _RET_IP_);
++ }
++ return ret;
++}
++EXPORT_SYMBOL(rt_spin_trylock_irqsave);
++
++int atomic_dec_and_spin_lock(atomic_t *atomic, spinlock_t *lock)
++{
++ /* Subtract 1 from counter unless that drops it to 0 (ie. it was 1) */
++ if (atomic_add_unless(atomic, -1, 1))
++ return 0;
++ rt_spin_lock(lock);
++ if (atomic_dec_and_test(atomic))
++ return 1;
++ rt_spin_unlock(lock);
++ return 0;
++}
++EXPORT_SYMBOL(atomic_dec_and_spin_lock);
++
++ void
++__rt_spin_lock_init(spinlock_t *lock, char *name, struct lock_class_key *key)
++{
++#ifdef CONFIG_DEBUG_LOCK_ALLOC
++ /*
++ * Make sure we are not reinitializing a held lock:
++ */
++ debug_check_no_locks_freed((void *)lock, sizeof(*lock));
++ lockdep_init_map(&lock->dep_map, name, key, 0);
++#endif
++}
++EXPORT_SYMBOL(__rt_spin_lock_init);
++
++#endif /* PREEMPT_RT_FULL */
++
++#ifdef CONFIG_PREEMPT_RT_FULL
++ static inline int __sched
++__mutex_lock_check_stamp(struct rt_mutex *lock, struct ww_acquire_ctx *ctx)
++{
++ struct ww_mutex *ww = container_of(lock, struct ww_mutex, base.lock);
++ struct ww_acquire_ctx *hold_ctx = ACCESS_ONCE(ww->ctx);
++
++ if (!hold_ctx)
++ return 0;
++
++ if (unlikely(ctx == hold_ctx))
++ return -EALREADY;
++
++ if (ctx->stamp - hold_ctx->stamp <= LONG_MAX &&
++ (ctx->stamp != hold_ctx->stamp || ctx > hold_ctx)) {
++#ifdef CONFIG_DEBUG_MUTEXES
++ DEBUG_LOCKS_WARN_ON(ctx->contending_lock);
++ ctx->contending_lock = ww;
++#endif
++ return -EDEADLK;
++ }
++
++ return 0;
++}
++#else
++ static inline int __sched
++__mutex_lock_check_stamp(struct rt_mutex *lock, struct ww_acquire_ctx *ctx)
++{
++ BUG();
++ return 0;
++}
++
++#endif
++
++static inline int
++try_to_take_rt_mutex(struct rt_mutex *lock, struct task_struct *task,
++ struct rt_mutex_waiter *waiter)
++{
++ return __try_to_take_rt_mutex(lock, task, waiter, STEAL_NORMAL);
++}
++
+ /*
+ * Task blocks on lock.
+ *
+@@ -971,6 +1445,23 @@
+ return -EDEADLK;
+
+ raw_spin_lock(&task->pi_lock);
++
++ /*
++ * In the case of futex requeue PI, this will be a proxy
++ * lock. The task will wake unaware that it is enqueueed on
++ * this lock. Avoid blocking on two locks and corrupting
++ * pi_blocked_on via the PI_WAKEUP_INPROGRESS
++ * flag. futex_wait_requeue_pi() sets this when it wakes up
++ * before requeue (due to a signal or timeout). Do not enqueue
++ * the task if PI_WAKEUP_INPROGRESS is set.
++ */
++ if (task != current && task->pi_blocked_on == PI_WAKEUP_INPROGRESS) {
++ raw_spin_unlock(&task->pi_lock);
++ return -EAGAIN;
++ }
++
++ BUG_ON(rt_mutex_real_waiter(task->pi_blocked_on));
++
+ __rt_mutex_adjust_prio(task);
+ waiter->task = task;
+ waiter->lock = lock;
+@@ -994,7 +1485,7 @@
+ rt_mutex_enqueue_pi(owner, waiter);
+
+ __rt_mutex_adjust_prio(owner);
+- if (owner->pi_blocked_on)
++ if (rt_mutex_real_waiter(owner->pi_blocked_on))
+ chain_walk = 1;
+ } else if (rt_mutex_cond_detect_deadlock(waiter, chwalk)) {
+ chain_walk = 1;
+@@ -1036,6 +1527,7 @@
+ * Called with lock->wait_lock held and interrupts disabled.
+ */
+ static void mark_wakeup_next_waiter(struct wake_q_head *wake_q,
++ struct wake_q_head *wake_sleeper_q,
+ struct rt_mutex *lock)
+ {
+ struct rt_mutex_waiter *waiter;
+@@ -1064,7 +1556,10 @@
+
+ raw_spin_unlock(&current->pi_lock);
+
+- wake_q_add(wake_q, waiter->task);
++ if (waiter->savestate)
++ wake_q_add(wake_sleeper_q, waiter->task);
++ else
++ wake_q_add(wake_q, waiter->task);
+ }
+
+ /*
+@@ -1078,7 +1573,7 @@
+ {
+ bool is_top_waiter = (waiter == rt_mutex_top_waiter(lock));
+ struct task_struct *owner = rt_mutex_owner(lock);
+- struct rt_mutex *next_lock;
++ struct rt_mutex *next_lock = NULL;
+
+ raw_spin_lock(&current->pi_lock);
+ rt_mutex_dequeue(lock, waiter);
+@@ -1102,7 +1597,8 @@
+ __rt_mutex_adjust_prio(owner);
+
+ /* Store the lock on which owner is blocked or NULL */
+- next_lock = task_blocked_on_lock(owner);
++ if (rt_mutex_real_waiter(owner->pi_blocked_on))
++ next_lock = task_blocked_on_lock(owner);
+
+ raw_spin_unlock(&owner->pi_lock);
+
+@@ -1138,17 +1634,17 @@
+ raw_spin_lock_irqsave(&task->pi_lock, flags);
+
+ waiter = task->pi_blocked_on;
+- if (!waiter || (waiter->prio == task->prio &&
++ if (!rt_mutex_real_waiter(waiter) || (waiter->prio == task->prio &&
+ !dl_prio(task->prio))) {
+ raw_spin_unlock_irqrestore(&task->pi_lock, flags);
+ return;
+ }
+ next_lock = waiter->lock;
+- raw_spin_unlock_irqrestore(&task->pi_lock, flags);
+
+ /* gets dropped in rt_mutex_adjust_prio_chain()! */
+ get_task_struct(task);
+
++ raw_spin_unlock_irqrestore(&task->pi_lock, flags);
+ rt_mutex_adjust_prio_chain(task, RT_MUTEX_MIN_CHAINWALK, NULL,
+ next_lock, NULL, task);
+ }
+@@ -1166,7 +1662,8 @@
+ static int __sched
+ __rt_mutex_slowlock(struct rt_mutex *lock, int state,
+ struct hrtimer_sleeper *timeout,
+- struct rt_mutex_waiter *waiter)
++ struct rt_mutex_waiter *waiter,
++ struct ww_acquire_ctx *ww_ctx)
+ {
+ int ret = 0;
+
+@@ -1189,6 +1686,12 @@
+ break;
+ }
+
++ if (ww_ctx && ww_ctx->acquired > 0) {
++ ret = __mutex_lock_check_stamp(lock, ww_ctx);
++ if (ret)
++ break;
++ }
++
+ raw_spin_unlock_irq(&lock->wait_lock);
+
+ debug_rt_mutex_print_deadlock(waiter);
+@@ -1223,21 +1726,96 @@
+ }
+ }
+
++static __always_inline void ww_mutex_lock_acquired(struct ww_mutex *ww,
++ struct ww_acquire_ctx *ww_ctx)
++{
++#ifdef CONFIG_DEBUG_MUTEXES
++ /*
++ * If this WARN_ON triggers, you used ww_mutex_lock to acquire,
++ * but released with a normal mutex_unlock in this call.
++ *
++ * This should never happen, always use ww_mutex_unlock.
++ */
++ DEBUG_LOCKS_WARN_ON(ww->ctx);
++
++ /*
++ * Not quite done after calling ww_acquire_done() ?
++ */
++ DEBUG_LOCKS_WARN_ON(ww_ctx->done_acquire);
++
++ if (ww_ctx->contending_lock) {
++ /*
++ * After -EDEADLK you tried to
++ * acquire a different ww_mutex? Bad!
++ */
++ DEBUG_LOCKS_WARN_ON(ww_ctx->contending_lock != ww);
++
++ /*
++ * You called ww_mutex_lock after receiving -EDEADLK,
++ * but 'forgot' to unlock everything else first?
++ */
++ DEBUG_LOCKS_WARN_ON(ww_ctx->acquired > 0);
++ ww_ctx->contending_lock = NULL;
++ }
++
++ /*
++ * Naughty, using a different class will lead to undefined behavior!
++ */
++ DEBUG_LOCKS_WARN_ON(ww_ctx->ww_class != ww->ww_class);
++#endif
++ ww_ctx->acquired++;
++}
++
++#ifdef CONFIG_PREEMPT_RT_FULL
++static void ww_mutex_account_lock(struct rt_mutex *lock,
++ struct ww_acquire_ctx *ww_ctx)
++{
++ struct ww_mutex *ww = container_of(lock, struct ww_mutex, base.lock);
++ struct rt_mutex_waiter *waiter, *n;
++
++ /*
++ * This branch gets optimized out for the common case,
++ * and is only important for ww_mutex_lock.
++ */
++ ww_mutex_lock_acquired(ww, ww_ctx);
++ ww->ctx = ww_ctx;
++
++ /*
++ * Give any possible sleeping processes the chance to wake up,
++ * so they can recheck if they have to back off.
++ */
++ rbtree_postorder_for_each_entry_safe(waiter, n, &lock->waiters,
++ tree_entry) {
++ /* XXX debug rt mutex waiter wakeup */
++
++ BUG_ON(waiter->lock != lock);
++ rt_mutex_wake_waiter(waiter);
++ }
++}
++
++#else
++
++static void ww_mutex_account_lock(struct rt_mutex *lock,
++ struct ww_acquire_ctx *ww_ctx)
++{
++ BUG();
++}
++#endif
++
+ /*
+ * Slow path lock function:
+ */
+ static int __sched
+ rt_mutex_slowlock(struct rt_mutex *lock, int state,
+ struct hrtimer_sleeper *timeout,
+- enum rtmutex_chainwalk chwalk)
++ enum rtmutex_chainwalk chwalk,
++ struct ww_acquire_ctx *ww_ctx)
+ {
+ struct rt_mutex_waiter waiter;
+ unsigned long flags;
+ int ret = 0;
+
+- debug_rt_mutex_init_waiter(&waiter);
+- RB_CLEAR_NODE(&waiter.pi_tree_entry);
+- RB_CLEAR_NODE(&waiter.tree_entry);
++ rt_mutex_init_waiter(&waiter, false);
+
+ /*
+ * Technically we could use raw_spin_[un]lock_irq() here, but this can
+@@ -1251,6 +1829,8 @@
+
+ /* Try to acquire the lock again: */
+ if (try_to_take_rt_mutex(lock, current, NULL)) {
++ if (ww_ctx)
++ ww_mutex_account_lock(lock, ww_ctx);
+ raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
+ return 0;
+ }
+@@ -1265,13 +1845,23 @@
+
+ if (likely(!ret))
+ /* sleep on the mutex */
+- ret = __rt_mutex_slowlock(lock, state, timeout, &waiter);
++ ret = __rt_mutex_slowlock(lock, state, timeout, &waiter,
++ ww_ctx);
++ else if (ww_ctx) {
++ /* ww_mutex received EDEADLK, let it become EALREADY */
++ ret = __mutex_lock_check_stamp(lock, ww_ctx);
++ BUG_ON(!ret);
++ }
+
+ if (unlikely(ret)) {
+ __set_current_state(TASK_RUNNING);
+ if (rt_mutex_has_waiters(lock))
+ remove_waiter(lock, &waiter);
+- rt_mutex_handle_deadlock(ret, chwalk, &waiter);
++ /* ww_mutex want to report EDEADLK/EALREADY, let them */
++ if (!ww_ctx)
++ rt_mutex_handle_deadlock(ret, chwalk, &waiter);
++ } else if (ww_ctx) {
++ ww_mutex_account_lock(lock, ww_ctx);
+ }
+
+ /*
+@@ -1331,7 +1921,8 @@
+ * Return whether the current task needs to undo a potential priority boosting.
+ */
+ static bool __sched rt_mutex_slowunlock(struct rt_mutex *lock,
+- struct wake_q_head *wake_q)
++ struct wake_q_head *wake_q,
++ struct wake_q_head *wake_sleeper_q)
+ {
+ unsigned long flags;
+
+@@ -1387,7 +1978,7 @@
+ *
+ * Queue the next waiter for wakeup once we release the wait_lock.
+ */
+- mark_wakeup_next_waiter(wake_q, lock);
++ mark_wakeup_next_waiter(wake_q, wake_sleeper_q, lock);
+
+ raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
+
+@@ -1403,31 +1994,36 @@
+ */
+ static inline int
+ rt_mutex_fastlock(struct rt_mutex *lock, int state,
++ struct ww_acquire_ctx *ww_ctx,
+ int (*slowfn)(struct rt_mutex *lock, int state,
+ struct hrtimer_sleeper *timeout,
+- enum rtmutex_chainwalk chwalk))
++ enum rtmutex_chainwalk chwalk,
++ struct ww_acquire_ctx *ww_ctx))
+ {
+ if (likely(rt_mutex_cmpxchg_acquire(lock, NULL, current))) {
+ rt_mutex_deadlock_account_lock(lock, current);
+ return 0;
+ } else
+- return slowfn(lock, state, NULL, RT_MUTEX_MIN_CHAINWALK);
++ return slowfn(lock, state, NULL, RT_MUTEX_MIN_CHAINWALK,
++ ww_ctx);
+ }
+
+ static inline int
+ rt_mutex_timed_fastlock(struct rt_mutex *lock, int state,
+ struct hrtimer_sleeper *timeout,
+ enum rtmutex_chainwalk chwalk,
++ struct ww_acquire_ctx *ww_ctx,
+ int (*slowfn)(struct rt_mutex *lock, int state,
+ struct hrtimer_sleeper *timeout,
+- enum rtmutex_chainwalk chwalk))
++ enum rtmutex_chainwalk chwalk,
++ struct ww_acquire_ctx *ww_ctx))
+ {
+ if (chwalk == RT_MUTEX_MIN_CHAINWALK &&
+ likely(rt_mutex_cmpxchg_acquire(lock, NULL, current))) {
+ rt_mutex_deadlock_account_lock(lock, current);
+ return 0;
+ } else
+- return slowfn(lock, state, timeout, chwalk);
++ return slowfn(lock, state, timeout, chwalk, ww_ctx);
+ }
+
+ static inline int
+@@ -1444,17 +2040,20 @@
+ static inline void
+ rt_mutex_fastunlock(struct rt_mutex *lock,
+ bool (*slowfn)(struct rt_mutex *lock,
+- struct wake_q_head *wqh))
++ struct wake_q_head *wqh,
++ struct wake_q_head *wq_sleeper))
+ {
+ WAKE_Q(wake_q);
++ WAKE_Q(wake_sleeper_q);
+
+ if (likely(rt_mutex_cmpxchg_release(lock, current, NULL))) {
+ rt_mutex_deadlock_account_unlock(current);
+
+ } else {
+- bool deboost = slowfn(lock, &wake_q);
++ bool deboost = slowfn(lock, &wake_q, &wake_sleeper_q);
+
+ wake_up_q(&wake_q);
++ wake_up_q_sleeper(&wake_sleeper_q);
+
+ /* Undo pi boosting if necessary: */
+ if (deboost)
+@@ -1471,7 +2070,7 @@
+ {
+ might_sleep();
+
+- rt_mutex_fastlock(lock, TASK_UNINTERRUPTIBLE, rt_mutex_slowlock);
++ rt_mutex_fastlock(lock, TASK_UNINTERRUPTIBLE, NULL, rt_mutex_slowlock);
+ }
+ EXPORT_SYMBOL_GPL(rt_mutex_lock);
+
+@@ -1488,7 +2087,7 @@
+ {
+ might_sleep();
+
+- return rt_mutex_fastlock(lock, TASK_INTERRUPTIBLE, rt_mutex_slowlock);
++ return rt_mutex_fastlock(lock, TASK_INTERRUPTIBLE, NULL, rt_mutex_slowlock);
+ }
+ EXPORT_SYMBOL_GPL(rt_mutex_lock_interruptible);
+
+@@ -1501,11 +2100,30 @@
+ might_sleep();
+
+ return rt_mutex_timed_fastlock(lock, TASK_INTERRUPTIBLE, timeout,
+- RT_MUTEX_FULL_CHAINWALK,
++ RT_MUTEX_FULL_CHAINWALK, NULL,
+ rt_mutex_slowlock);
+ }
+
+ /**
++ * rt_mutex_lock_killable - lock a rt_mutex killable
++ *
++ * @lock: the rt_mutex to be locked
++ * @detect_deadlock: deadlock detection on/off
++ *
++ * Returns:
++ * 0 on success
++ * -EINTR when interrupted by a signal
++ * -EDEADLK when the lock would deadlock (when deadlock detection is on)
++ */
++int __sched rt_mutex_lock_killable(struct rt_mutex *lock)
++{
++ might_sleep();
++
++ return rt_mutex_fastlock(lock, TASK_KILLABLE, NULL, rt_mutex_slowlock);
++}
++EXPORT_SYMBOL_GPL(rt_mutex_lock_killable);
++
++/**
+ * rt_mutex_timed_lock - lock a rt_mutex interruptible
+ * the timeout structure is provided
+ * by the caller
+@@ -1525,6 +2143,7 @@
+
+ return rt_mutex_timed_fastlock(lock, TASK_INTERRUPTIBLE, timeout,
+ RT_MUTEX_MIN_CHAINWALK,
++ NULL,
+ rt_mutex_slowlock);
+ }
+ EXPORT_SYMBOL_GPL(rt_mutex_timed_lock);
+@@ -1542,7 +2161,11 @@
+ */
+ int __sched rt_mutex_trylock(struct rt_mutex *lock)
+ {
++#ifdef CONFIG_PREEMPT_RT_FULL
++ if (WARN_ON_ONCE(in_irq() || in_nmi()))
++#else
+ if (WARN_ON_ONCE(in_irq() || in_nmi() || in_serving_softirq()))
++#endif
+ return 0;
+
+ return rt_mutex_fasttrylock(lock, rt_mutex_slowtrylock);
+@@ -1568,13 +2191,14 @@
+ * required or not.
+ */
+ bool __sched rt_mutex_futex_unlock(struct rt_mutex *lock,
+- struct wake_q_head *wqh)
++ struct wake_q_head *wqh,
++ struct wake_q_head *wq_sleeper)
+ {
+ if (likely(rt_mutex_cmpxchg_release(lock, current, NULL))) {
+ rt_mutex_deadlock_account_unlock(current);
+ return false;
+ }
+- return rt_mutex_slowunlock(lock, wqh);
++ return rt_mutex_slowunlock(lock, wqh, wq_sleeper);
+ }
+
+ /**
+@@ -1607,13 +2231,12 @@
+ void __rt_mutex_init(struct rt_mutex *lock, const char *name)
+ {
+ lock->owner = NULL;
+- raw_spin_lock_init(&lock->wait_lock);
+ lock->waiters = RB_ROOT;
+ lock->waiters_leftmost = NULL;
+
+ debug_rt_mutex_init(lock, name);
+ }
+-EXPORT_SYMBOL_GPL(__rt_mutex_init);
++EXPORT_SYMBOL(__rt_mutex_init);
+
+ /**
+ * rt_mutex_init_proxy_locked - initialize and lock a rt_mutex on behalf of a
+@@ -1628,7 +2251,7 @@
+ void rt_mutex_init_proxy_locked(struct rt_mutex *lock,
+ struct task_struct *proxy_owner)
+ {
+- __rt_mutex_init(lock, NULL);
++ rt_mutex_init(lock);
+ debug_rt_mutex_proxy_lock(lock, proxy_owner);
+ rt_mutex_set_owner(lock, proxy_owner);
+ rt_mutex_deadlock_account_lock(lock, proxy_owner);
+@@ -1676,6 +2299,35 @@
+ return 1;
+ }
+
++#ifdef CONFIG_PREEMPT_RT_FULL
++ /*
++ * In PREEMPT_RT there's an added race.
++ * If the task, that we are about to requeue, times out,
++ * it can set the PI_WAKEUP_INPROGRESS. This tells the requeue
++ * to skip this task. But right after the task sets
++ * its pi_blocked_on to PI_WAKEUP_INPROGRESS it can then
++ * block on the spin_lock(&hb->lock), which in RT is an rtmutex.
++ * This will replace the PI_WAKEUP_INPROGRESS with the actual
++ * lock that it blocks on. We *must not* place this task
++ * on this proxy lock in that case.
++ *
++ * To prevent this race, we first take the task's pi_lock
++ * and check if it has updated its pi_blocked_on. If it has,
++ * we assume that it woke up and we return -EAGAIN.
++ * Otherwise, we set the task's pi_blocked_on to
++ * PI_REQUEUE_INPROGRESS, so that if the task is waking up
++ * it will know that we are in the process of requeuing it.
++ */
++ raw_spin_lock(&task->pi_lock);
++ if (task->pi_blocked_on) {
++ raw_spin_unlock(&task->pi_lock);
++ raw_spin_unlock_irq(&lock->wait_lock);
++ return -EAGAIN;
++ }
++ task->pi_blocked_on = PI_REQUEUE_INPROGRESS;
++ raw_spin_unlock(&task->pi_lock);
++#endif
++
+ /* We enforce deadlock detection for futexes */
+ ret = task_blocks_on_rt_mutex(lock, waiter, task,
+ RT_MUTEX_FULL_CHAINWALK);
+@@ -1690,7 +2342,7 @@
+ ret = 0;
+ }
+
+- if (unlikely(ret))
++ if (ret && rt_mutex_has_waiters(lock))
+ remove_waiter(lock, waiter);
+
+ raw_spin_unlock_irq(&lock->wait_lock);
+@@ -1746,7 +2398,7 @@
+ set_current_state(TASK_INTERRUPTIBLE);
+
+ /* sleep on the mutex */
+- ret = __rt_mutex_slowlock(lock, TASK_INTERRUPTIBLE, to, waiter);
++ ret = __rt_mutex_slowlock(lock, TASK_INTERRUPTIBLE, to, waiter, NULL);
+
+ if (unlikely(ret))
+ remove_waiter(lock, waiter);
+@@ -1761,3 +2413,89 @@
+
+ return ret;
+ }
++
++static inline int
++ww_mutex_deadlock_injection(struct ww_mutex *lock, struct ww_acquire_ctx *ctx)
++{
++#ifdef CONFIG_DEBUG_WW_MUTEX_SLOWPATH
++ unsigned tmp;
++
++ if (ctx->deadlock_inject_countdown-- == 0) {
++ tmp = ctx->deadlock_inject_interval;
++ if (tmp > UINT_MAX/4)
++ tmp = UINT_MAX;
++ else
++ tmp = tmp*2 + tmp + tmp/2;
++
++ ctx->deadlock_inject_interval = tmp;
++ ctx->deadlock_inject_countdown = tmp;
++ ctx->contending_lock = lock;
++
++ ww_mutex_unlock(lock);
++
++ return -EDEADLK;
++ }
++#endif
++
++ return 0;
++}
++
++#ifdef CONFIG_PREEMPT_RT_FULL
++int __sched
++__ww_mutex_lock_interruptible(struct ww_mutex *lock, struct ww_acquire_ctx *ww_ctx)
++{
++ int ret;
++
++ might_sleep();
++
++ mutex_acquire_nest(&lock->base.dep_map, 0, 0, &ww_ctx->dep_map, _RET_IP_);
++ ret = rt_mutex_slowlock(&lock->base.lock, TASK_INTERRUPTIBLE, NULL, 0, ww_ctx);
++ if (ret)
++ mutex_release(&lock->base.dep_map, 1, _RET_IP_);
++ else if (!ret && ww_ctx->acquired > 1)
++ return ww_mutex_deadlock_injection(lock, ww_ctx);
++
++ return ret;
++}
++EXPORT_SYMBOL_GPL(__ww_mutex_lock_interruptible);
++
++int __sched
++__ww_mutex_lock(struct ww_mutex *lock, struct ww_acquire_ctx *ww_ctx)
++{
++ int ret;
++
++ might_sleep();
++
++ mutex_acquire_nest(&lock->base.dep_map, 0, 0, &ww_ctx->dep_map, _RET_IP_);
++ ret = rt_mutex_slowlock(&lock->base.lock, TASK_UNINTERRUPTIBLE, NULL, 0, ww_ctx);
++ if (ret)
++ mutex_release(&lock->base.dep_map, 1, _RET_IP_);
++ else if (!ret && ww_ctx->acquired > 1)
++ return ww_mutex_deadlock_injection(lock, ww_ctx);
++
++ return ret;
++}
++EXPORT_SYMBOL_GPL(__ww_mutex_lock);
++
++void __sched ww_mutex_unlock(struct ww_mutex *lock)
++{
++ int nest = !!lock->ctx;
++
++ /*
++ * The unlocking fastpath is the 0->1 transition from 'locked'
++ * into 'unlocked' state:
++ */
++ if (nest) {
++#ifdef CONFIG_DEBUG_MUTEXES
++ DEBUG_LOCKS_WARN_ON(!lock->ctx->acquired);
++#endif
++ if (lock->ctx->acquired > 0)
++ lock->ctx->acquired--;
++ lock->ctx = NULL;
++ }
++
++ mutex_release(&lock->base.dep_map, nest, _RET_IP_);
++ rt_mutex_unlock(&lock->base.lock);
++}
++EXPORT_SYMBOL(ww_mutex_unlock);
++#endif
+diff -Nur linux-4.8.15.orig/kernel/locking/rtmutex_common.h linux-4.8.15/kernel/locking/rtmutex_common.h
+--- linux-4.8.15.orig/kernel/locking/rtmutex_common.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/locking/rtmutex_common.h 2017-01-01 17:07:16.023426438 +0100
+@@ -27,6 +27,7 @@
+ struct rb_node pi_tree_entry;
+ struct task_struct *task;
+ struct rt_mutex *lock;
++ bool savestate;
+ #ifdef CONFIG_DEBUG_RT_MUTEXES
+ unsigned long ip;
+ struct pid *deadlock_task_pid;
+@@ -98,6 +99,9 @@
+ /*
+ * PI-futex support (proxy locking functions, etc.):
+ */
++#define PI_WAKEUP_INPROGRESS ((struct rt_mutex_waiter *) 1)
++#define PI_REQUEUE_INPROGRESS ((struct rt_mutex_waiter *) 2)
++
+ extern struct task_struct *rt_mutex_next_owner(struct rt_mutex *lock);
+ extern void rt_mutex_init_proxy_locked(struct rt_mutex *lock,
+ struct task_struct *proxy_owner);
+@@ -111,7 +115,8 @@
+ struct rt_mutex_waiter *waiter);
+ extern int rt_mutex_timed_futex_lock(struct rt_mutex *l, struct hrtimer_sleeper *to);
+ extern bool rt_mutex_futex_unlock(struct rt_mutex *lock,
+- struct wake_q_head *wqh);
++ struct wake_q_head *wqh,
++ struct wake_q_head *wq_sleeper);
+ extern void rt_mutex_adjust_prio(struct task_struct *task);
+
+ #ifdef CONFIG_DEBUG_RT_MUTEXES
+@@ -120,4 +125,14 @@
+ # include "rtmutex.h"
+ #endif
+
++static inline void
++rt_mutex_init_waiter(struct rt_mutex_waiter *waiter, bool savestate)
++{
++ debug_rt_mutex_init_waiter(waiter);
++ waiter->task = NULL;
++ waiter->savestate = savestate;
++ RB_CLEAR_NODE(&waiter->pi_tree_entry);
++ RB_CLEAR_NODE(&waiter->tree_entry);
++}
++
+ #endif
+diff -Nur linux-4.8.15.orig/kernel/locking/spinlock.c linux-4.8.15/kernel/locking/spinlock.c
+--- linux-4.8.15.orig/kernel/locking/spinlock.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/locking/spinlock.c 2017-01-01 17:07:16.023426438 +0100
+@@ -124,8 +124,11 @@
+ * __[spin|read|write]_lock_bh()
+ */
+ BUILD_LOCK_OPS(spin, raw_spinlock);
++
++#ifndef CONFIG_PREEMPT_RT_FULL
+ BUILD_LOCK_OPS(read, rwlock);
+ BUILD_LOCK_OPS(write, rwlock);
++#endif
+
+ #endif
+
+@@ -209,6 +212,8 @@
+ EXPORT_SYMBOL(_raw_spin_unlock_bh);
+ #endif
+
++#ifndef CONFIG_PREEMPT_RT_FULL
++
+ #ifndef CONFIG_INLINE_READ_TRYLOCK
+ int __lockfunc _raw_read_trylock(rwlock_t *lock)
+ {
+@@ -353,6 +358,8 @@
+ EXPORT_SYMBOL(_raw_write_unlock_bh);
+ #endif
+
++#endif /* !PREEMPT_RT_FULL */
++
+ #ifdef CONFIG_DEBUG_LOCK_ALLOC
+
+ void __lockfunc _raw_spin_lock_nested(raw_spinlock_t *lock, int subclass)
+diff -Nur linux-4.8.15.orig/kernel/locking/spinlock_debug.c linux-4.8.15/kernel/locking/spinlock_debug.c
+--- linux-4.8.15.orig/kernel/locking/spinlock_debug.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/locking/spinlock_debug.c 2017-01-01 17:07:16.023426438 +0100
+@@ -31,6 +31,7 @@
+
+ EXPORT_SYMBOL(__raw_spin_lock_init);
+
++#ifndef CONFIG_PREEMPT_RT_FULL
+ void __rwlock_init(rwlock_t *lock, const char *name,
+ struct lock_class_key *key)
+ {
+@@ -48,6 +49,7 @@
+ }
+
+ EXPORT_SYMBOL(__rwlock_init);
++#endif
+
+ static void spin_dump(raw_spinlock_t *lock, const char *msg)
+ {
+@@ -159,6 +161,7 @@
+ arch_spin_unlock(&lock->raw_lock);
+ }
+
++#ifndef CONFIG_PREEMPT_RT_FULL
+ static void rwlock_bug(rwlock_t *lock, const char *msg)
+ {
+ if (!debug_locks_off())
+@@ -300,3 +303,5 @@
+ debug_write_unlock(lock);
+ arch_write_unlock(&lock->raw_lock);
+ }
++
++#endif
+diff -Nur linux-4.8.15.orig/kernel/Makefile linux-4.8.15/kernel/Makefile
+--- linux-4.8.15.orig/kernel/Makefile 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/Makefile 2017-01-01 17:07:15.995424645 +0100
+@@ -11,6 +11,13 @@
+ notifier.o ksysfs.o cred.o reboot.o \
+ async.o range.o smpboot.o
+
++# Tracing may do some dangerous __builtin_return_address() operations
++# We know they are dangerous, we don't need gcc telling us that.
++ifdef CONFIG_USING_GET_LOCK_PARENT_IP
++FRAME_CFLAGS := $(call cc-disable-warning,frame-address)
++KBUILD_CFLAGS += $(FRAME_CFLAGS)
++endif
++
+ obj-$(CONFIG_MULTIUSER) += groups.o
+
+ ifdef CONFIG_FUNCTION_TRACER
+diff -Nur linux-4.8.15.orig/kernel/panic.c linux-4.8.15/kernel/panic.c
+--- linux-4.8.15.orig/kernel/panic.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/panic.c 2017-01-01 17:07:16.023426438 +0100
+@@ -449,9 +449,11 @@
+
+ static int init_oops_id(void)
+ {
++#ifndef CONFIG_PREEMPT_RT_FULL
+ if (!oops_id)
+ get_random_bytes(&oops_id, sizeof(oops_id));
+ else
++#endif
+ oops_id++;
+
+ return 0;
+diff -Nur linux-4.8.15.orig/kernel/power/hibernate.c linux-4.8.15/kernel/power/hibernate.c
+--- linux-4.8.15.orig/kernel/power/hibernate.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/power/hibernate.c 2017-01-01 17:07:16.023426438 +0100
+@@ -286,6 +286,8 @@
+
+ local_irq_disable();
+
++ system_state = SYSTEM_SUSPEND;
++
+ error = syscore_suspend();
+ if (error) {
+ printk(KERN_ERR "PM: Some system devices failed to power down, "
+@@ -315,6 +317,7 @@
+ syscore_resume();
+
+ Enable_irqs:
++ system_state = SYSTEM_RUNNING;
+ local_irq_enable();
+
+ Enable_cpus:
+@@ -444,6 +447,7 @@
+ goto Enable_cpus;
+
+ local_irq_disable();
++ system_state = SYSTEM_SUSPEND;
+
+ error = syscore_suspend();
+ if (error)
+@@ -477,6 +481,7 @@
+ syscore_resume();
+
+ Enable_irqs:
++ system_state = SYSTEM_RUNNING;
+ local_irq_enable();
+
+ Enable_cpus:
+@@ -562,6 +567,7 @@
+ goto Enable_cpus;
+
+ local_irq_disable();
++ system_state = SYSTEM_SUSPEND;
+ syscore_suspend();
+ if (pm_wakeup_pending()) {
+ error = -EAGAIN;
+@@ -574,6 +580,7 @@
+
+ Power_up:
+ syscore_resume();
++ system_state = SYSTEM_RUNNING;
+ local_irq_enable();
+
+ Enable_cpus:
+@@ -674,6 +681,10 @@
+ return error;
+ }
+
++#ifndef CONFIG_SUSPEND
++bool pm_in_action;
++#endif
++
+ /**
+ * hibernate - Carry out system hibernation, including saving the image.
+ */
+@@ -687,6 +698,8 @@
+ return -EPERM;
+ }
+
++ pm_in_action = true;
++
+ lock_system_sleep();
+ /* The snapshot device should not be opened while we're running */
+ if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
+@@ -764,6 +777,7 @@
+ atomic_inc(&snapshot_device_available);
+ Unlock:
+ unlock_system_sleep();
++ pm_in_action = false;
+ return error;
+ }
+
+diff -Nur linux-4.8.15.orig/kernel/power/suspend.c linux-4.8.15/kernel/power/suspend.c
+--- linux-4.8.15.orig/kernel/power/suspend.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/power/suspend.c 2017-01-01 17:07:16.023426438 +0100
+@@ -361,6 +361,8 @@
+ arch_suspend_disable_irqs();
+ BUG_ON(!irqs_disabled());
+
++ system_state = SYSTEM_SUSPEND;
++
+ error = syscore_suspend();
+ if (!error) {
+ *wakeup = pm_wakeup_pending();
+@@ -377,6 +379,8 @@
+ syscore_resume();
+ }
+
++ system_state = SYSTEM_RUNNING;
++
+ arch_suspend_enable_irqs();
+ BUG_ON(irqs_disabled());
+
+@@ -519,6 +523,8 @@
+ return error;
+ }
+
++bool pm_in_action;
++
+ /**
+ * pm_suspend - Externally visible function for suspending the system.
+ * @state: System sleep state to enter.
+@@ -533,6 +539,8 @@
+ if (state <= PM_SUSPEND_ON || state >= PM_SUSPEND_MAX)
+ return -EINVAL;
+
++ pm_in_action = true;
++
+ error = enter_state(state);
+ if (error) {
+ suspend_stats.fail++;
+@@ -540,6 +548,7 @@
+ } else {
+ suspend_stats.success++;
+ }
++ pm_in_action = false;
+ return error;
+ }
+ EXPORT_SYMBOL(pm_suspend);
+diff -Nur linux-4.8.15.orig/kernel/printk/printk.c linux-4.8.15/kernel/printk/printk.c
+--- linux-4.8.15.orig/kernel/printk/printk.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/printk/printk.c 2017-01-01 17:07:16.027426711 +0100
+@@ -351,6 +351,65 @@
+ */
+ DEFINE_RAW_SPINLOCK(logbuf_lock);
+
++#ifdef CONFIG_EARLY_PRINTK
++struct console *early_console;
++
++static void early_vprintk(const char *fmt, va_list ap)
++{
++ if (early_console) {
++ char buf[512];
++ int n = vscnprintf(buf, sizeof(buf), fmt, ap);
++
++ early_console->write(early_console, buf, n);
++ }
++}
++
++asmlinkage void early_printk(const char *fmt, ...)
++{
++ va_list ap;
++
++ va_start(ap, fmt);
++ early_vprintk(fmt, ap);
++ va_end(ap);
++}
++
++/*
++ * This is independent of any log levels - a global
++ * kill switch that turns off all of printk.
++ *
++ * Used by the NMI watchdog if early-printk is enabled.
++ */
++static bool __read_mostly printk_killswitch;
++
++static int __init force_early_printk_setup(char *str)
++{
++ printk_killswitch = true;
++ return 0;
++}
++early_param("force_early_printk", force_early_printk_setup);
++
++void printk_kill(void)
++{
++ printk_killswitch = true;
++}
++
++#ifdef CONFIG_PRINTK
++static int forced_early_printk(const char *fmt, va_list ap)
++{
++ if (!printk_killswitch)
++ return 0;
++ early_vprintk(fmt, ap);
++ return 1;
++}
++#endif
++
++#else
++static inline int forced_early_printk(const char *fmt, va_list ap)
++{
++ return 0;
++}
++#endif
++
+ #ifdef CONFIG_PRINTK
+ DECLARE_WAIT_QUEUE_HEAD(log_wait);
+ /* the next printk record to read by syslog(READ) or /proc/kmsg */
+@@ -1340,6 +1399,7 @@
+ {
+ char *text;
+ int len = 0;
++ int attempts = 0;
+
+ text = kmalloc(LOG_LINE_MAX + PREFIX_MAX, GFP_KERNEL);
+ if (!text)
+@@ -1351,6 +1411,14 @@
+ u64 seq;
+ u32 idx;
+ enum log_flags prev;
++ int num_msg;
++try_again:
++ attempts++;
++ if (attempts > 10) {
++ len = -EBUSY;
++ goto out;
++ }
++ num_msg = 0;
+
+ /*
+ * Find first record that fits, including all following records,
+@@ -1366,6 +1434,14 @@
+ prev = msg->flags;
+ idx = log_next(idx);
+ seq++;
++ num_msg++;
++ if (num_msg > 5) {
++ num_msg = 0;
++ raw_spin_unlock_irq(&logbuf_lock);
++ raw_spin_lock_irq(&logbuf_lock);
++ if (clear_seq < log_first_seq)
++ goto try_again;
++ }
+ }
+
+ /* move first record forward until length fits into the buffer */
+@@ -1379,6 +1455,14 @@
+ prev = msg->flags;
+ idx = log_next(idx);
+ seq++;
++ num_msg++;
++ if (num_msg > 5) {
++ num_msg = 0;
++ raw_spin_unlock_irq(&logbuf_lock);
++ raw_spin_lock_irq(&logbuf_lock);
++ if (clear_seq < log_first_seq)
++ goto try_again;
++ }
+ }
+
+ /* last message fitting into this dump */
+@@ -1419,6 +1503,7 @@
+ clear_seq = log_next_seq;
+ clear_idx = log_next_idx;
+ }
++out:
+ raw_spin_unlock_irq(&logbuf_lock);
+
+ kfree(text);
+@@ -1572,6 +1657,12 @@
+ if (!console_drivers)
+ return;
+
++ if (IS_ENABLED(CONFIG_PREEMPT_RT_BASE)) {
++ if (in_irq() || in_nmi())
++ return;
++ }
++
++ migrate_disable();
+ for_each_console(con) {
+ if (exclusive_console && con != exclusive_console)
+ continue;
+@@ -1587,6 +1678,7 @@
+ else
+ con->write(con, text, len);
+ }
++ migrate_enable();
+ }
+
+ /*
+@@ -1750,6 +1842,13 @@
+ /* cpu currently holding logbuf_lock in this function */
+ static unsigned int logbuf_cpu = UINT_MAX;
+
++ /*
++ * Fall back to early_printk if a debugging subsystem has
++ * killed printk output
++ */
++ if (unlikely(forced_early_printk(fmt, args)))
++ return 1;
++
+ if (level == LOGLEVEL_SCHED) {
+ level = LOGLEVEL_DEFAULT;
+ in_sched = true;
+@@ -1894,13 +1993,23 @@
+
+ /* If called from the scheduler, we can not call up(). */
+ if (!in_sched) {
++ int may_trylock = 1;
++
+ lockdep_off();
++#ifdef CONFIG_PREEMPT_RT_FULL
++ /*
++ * we can't take a sleeping lock with IRQs or preeption disabled
++ * so we can't print in these contexts
++ */
++ if (!(preempt_count() == 0 && !irqs_disabled()))
++ may_trylock = 0;
++#endif
+ /*
+ * Try to acquire and then immediately release the console
+ * semaphore. The release will print out buffers and wake up
+ * /dev/kmsg and syslog() users.
+ */
+- if (console_trylock())
++ if (may_trylock && console_trylock())
+ console_unlock();
+ lockdep_on();
+ }
+@@ -2023,26 +2132,6 @@
+
+ #endif /* CONFIG_PRINTK */
+
+-#ifdef CONFIG_EARLY_PRINTK
+-struct console *early_console;
+-
+-asmlinkage __visible void early_printk(const char *fmt, ...)
+-{
+- va_list ap;
+- char buf[512];
+- int n;
+-
+- if (!early_console)
+- return;
+-
+- va_start(ap, fmt);
+- n = vscnprintf(buf, sizeof(buf), fmt, ap);
+- va_end(ap);
+-
+- early_console->write(early_console, buf, n);
+-}
+-#endif
+-
+ static int __add_preferred_console(char *name, int idx, char *options,
+ char *brl_options)
+ {
+@@ -2312,11 +2401,16 @@
+ goto out;
+
+ len = cont_print_text(text, size);
++#ifdef CONFIG_PREEMPT_RT_FULL
++ raw_spin_unlock_irqrestore(&logbuf_lock, flags);
++ call_console_drivers(cont.level, NULL, 0, text, len);
++#else
+ raw_spin_unlock(&logbuf_lock);
+ stop_critical_timings();
+ call_console_drivers(cont.level, NULL, 0, text, len);
+ start_critical_timings();
+ local_irq_restore(flags);
++#endif
+ return;
+ out:
+ raw_spin_unlock_irqrestore(&logbuf_lock, flags);
+@@ -2440,13 +2534,17 @@
+ console_idx = log_next(console_idx);
+ console_seq++;
+ console_prev = msg->flags;
++#ifdef CONFIG_PREEMPT_RT_FULL
++ raw_spin_unlock_irqrestore(&logbuf_lock, flags);
++ call_console_drivers(level, ext_text, ext_len, text, len);
++#else
+ raw_spin_unlock(&logbuf_lock);
+
+ stop_critical_timings(); /* don't trace print latency */
+ call_console_drivers(level, ext_text, ext_len, text, len);
+ start_critical_timings();
+ local_irq_restore(flags);
+-
++#endif
+ if (do_cond_resched)
+ cond_resched();
+ }
+@@ -2498,6 +2596,11 @@
+ {
+ struct console *c;
+
++ if (IS_ENABLED(CONFIG_PREEMPT_RT_BASE)) {
++ if (in_irq() || in_nmi())
++ return;
++ }
++
+ /*
+ * console_unblank can no longer be called in interrupt context unless
+ * oops_in_progress is set to 1..
+diff -Nur linux-4.8.15.orig/kernel/ptrace.c linux-4.8.15/kernel/ptrace.c
+--- linux-4.8.15.orig/kernel/ptrace.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/ptrace.c 2017-01-01 17:07:16.027426711 +0100
+@@ -128,7 +128,14 @@
+
+ spin_lock_irq(&task->sighand->siglock);
+ if (task_is_traced(task) && !__fatal_signal_pending(task)) {
+- task->state = __TASK_TRACED;
++ unsigned long flags;
++
++ raw_spin_lock_irqsave(&task->pi_lock, flags);
++ if (task->state & __TASK_TRACED)
++ task->state = __TASK_TRACED;
++ else
++ task->saved_state = __TASK_TRACED;
++ raw_spin_unlock_irqrestore(&task->pi_lock, flags);
+ ret = true;
+ }
+ spin_unlock_irq(&task->sighand->siglock);
+diff -Nur linux-4.8.15.orig/kernel/rcu/rcutorture.c linux-4.8.15/kernel/rcu/rcutorture.c
+--- linux-4.8.15.orig/kernel/rcu/rcutorture.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/rcu/rcutorture.c 2017-01-01 17:07:16.027426711 +0100
+@@ -404,6 +404,7 @@
+ .name = "rcu"
+ };
+
++#ifndef CONFIG_PREEMPT_RT_FULL
+ /*
+ * Definitions for rcu_bh torture testing.
+ */
+@@ -443,6 +444,12 @@
+ .name = "rcu_bh"
+ };
+
++#else
++static struct rcu_torture_ops rcu_bh_ops = {
++ .ttype = INVALID_RCU_FLAVOR,
++};
++#endif
++
+ /*
+ * Don't even think about trying any of these in real life!!!
+ * The names includes "busted", and they really means it!
+diff -Nur linux-4.8.15.orig/kernel/rcu/tree.c linux-4.8.15/kernel/rcu/tree.c
+--- linux-4.8.15.orig/kernel/rcu/tree.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/rcu/tree.c 2017-01-01 17:07:16.027426711 +0100
+@@ -56,6 +56,11 @@
+ #include <linux/random.h>
+ #include <linux/trace_events.h>
+ #include <linux/suspend.h>
++#include <linux/delay.h>
++#include <linux/gfp.h>
++#include <linux/oom.h>
++#include <linux/smpboot.h>
++#include "../time/tick-internal.h"
+
+ #include "tree.h"
+ #include "rcu.h"
+@@ -259,6 +264,19 @@
+ this_cpu_ptr(&rcu_sched_data), true);
+ }
+
++#ifdef CONFIG_PREEMPT_RT_FULL
++static void rcu_preempt_qs(void);
++
++void rcu_bh_qs(void)
++{
++ unsigned long flags;
++
++ /* Callers to this function, rcu_preempt_qs(), must disable irqs. */
++ local_irq_save(flags);
++ rcu_preempt_qs();
++ local_irq_restore(flags);
++}
++#else
+ void rcu_bh_qs(void)
+ {
+ if (__this_cpu_read(rcu_bh_data.cpu_no_qs.s)) {
+@@ -268,6 +286,7 @@
+ __this_cpu_write(rcu_bh_data.cpu_no_qs.b.norm, false);
+ }
+ }
++#endif
+
+ static DEFINE_PER_CPU(int, rcu_sched_qs_mask);
+
+@@ -448,11 +467,13 @@
+ /*
+ * Return the number of RCU BH batches started thus far for debug & stats.
+ */
++#ifndef CONFIG_PREEMPT_RT_FULL
+ unsigned long rcu_batches_started_bh(void)
+ {
+ return rcu_bh_state.gpnum;
+ }
+ EXPORT_SYMBOL_GPL(rcu_batches_started_bh);
++#endif
+
+ /*
+ * Return the number of RCU batches completed thus far for debug & stats.
+@@ -472,6 +493,7 @@
+ }
+ EXPORT_SYMBOL_GPL(rcu_batches_completed_sched);
+
++#ifndef CONFIG_PREEMPT_RT_FULL
+ /*
+ * Return the number of RCU BH batches completed thus far for debug & stats.
+ */
+@@ -480,6 +502,7 @@
+ return rcu_bh_state.completed;
+ }
+ EXPORT_SYMBOL_GPL(rcu_batches_completed_bh);
++#endif
+
+ /*
+ * Return the number of RCU expedited batches completed thus far for
+@@ -503,6 +526,7 @@
+ }
+ EXPORT_SYMBOL_GPL(rcu_exp_batches_completed_sched);
+
++#ifndef CONFIG_PREEMPT_RT_FULL
+ /*
+ * Force a quiescent state.
+ */
+@@ -521,6 +545,13 @@
+ }
+ EXPORT_SYMBOL_GPL(rcu_bh_force_quiescent_state);
+
++#else
++void rcu_force_quiescent_state(void)
++{
++}
++EXPORT_SYMBOL_GPL(rcu_force_quiescent_state);
++#endif
++
+ /*
+ * Force a quiescent state for RCU-sched.
+ */
+@@ -571,9 +602,11 @@
+ case RCU_FLAVOR:
+ rsp = rcu_state_p;
+ break;
++#ifndef CONFIG_PREEMPT_RT_FULL
+ case RCU_BH_FLAVOR:
+ rsp = &rcu_bh_state;
+ break;
++#endif
+ case RCU_SCHED_FLAVOR:
+ rsp = &rcu_sched_state;
+ break;
+@@ -3013,18 +3046,17 @@
+ /*
+ * Do RCU core processing for the current CPU.
+ */
+-static void rcu_process_callbacks(struct softirq_action *unused)
++static void rcu_process_callbacks(void)
+ {
+ struct rcu_state *rsp;
+
+ if (cpu_is_offline(smp_processor_id()))
+ return;
+- trace_rcu_utilization(TPS("Start RCU core"));
+ for_each_rcu_flavor(rsp)
+ __rcu_process_callbacks(rsp);
+- trace_rcu_utilization(TPS("End RCU core"));
+ }
+
++static DEFINE_PER_CPU(struct task_struct *, rcu_cpu_kthread_task);
+ /*
+ * Schedule RCU callback invocation. If the specified type of RCU
+ * does not support RCU priority boosting, just do a direct call,
+@@ -3036,18 +3068,105 @@
+ {
+ if (unlikely(!READ_ONCE(rcu_scheduler_fully_active)))
+ return;
+- if (likely(!rsp->boost)) {
+- rcu_do_batch(rsp, rdp);
++ rcu_do_batch(rsp, rdp);
++}
++
++static void rcu_wake_cond(struct task_struct *t, int status)
++{
++ /*
++ * If the thread is yielding, only wake it when this
++ * is invoked from idle
++ */
++ if (t && (status != RCU_KTHREAD_YIELDING || is_idle_task(current)))
++ wake_up_process(t);
++}
++
++/*
++ * Wake up this CPU's rcuc kthread to do RCU core processing.
++ */
++static void invoke_rcu_core(void)
++{
++ unsigned long flags;
++ struct task_struct *t;
++
++ if (!cpu_online(smp_processor_id()))
+ return;
++ local_irq_save(flags);
++ __this_cpu_write(rcu_cpu_has_work, 1);
++ t = __this_cpu_read(rcu_cpu_kthread_task);
++ if (t != NULL && current != t)
++ rcu_wake_cond(t, __this_cpu_read(rcu_cpu_kthread_status));
++ local_irq_restore(flags);
++}
++
++static void rcu_cpu_kthread_park(unsigned int cpu)
++{
++ per_cpu(rcu_cpu_kthread_status, cpu) = RCU_KTHREAD_OFFCPU;
++}
++
++static int rcu_cpu_kthread_should_run(unsigned int cpu)
++{
++ return __this_cpu_read(rcu_cpu_has_work);
++}
++
++/*
++ * Per-CPU kernel thread that invokes RCU callbacks. This replaces the
++ * RCU softirq used in flavors and configurations of RCU that do not
++ * support RCU priority boosting.
++ */
++static void rcu_cpu_kthread(unsigned int cpu)
++{
++ unsigned int *statusp = this_cpu_ptr(&rcu_cpu_kthread_status);
++ char work, *workp = this_cpu_ptr(&rcu_cpu_has_work);
++ int spincnt;
++
++ for (spincnt = 0; spincnt < 10; spincnt++) {
++ trace_rcu_utilization(TPS("Start CPU kthread@rcu_wait"));
++ local_bh_disable();
++ *statusp = RCU_KTHREAD_RUNNING;
++ this_cpu_inc(rcu_cpu_kthread_loops);
++ local_irq_disable();
++ work = *workp;
++ *workp = 0;
++ local_irq_enable();
++ if (work)
++ rcu_process_callbacks();
++ local_bh_enable();
++ if (*workp == 0) {
++ trace_rcu_utilization(TPS("End CPU kthread@rcu_wait"));
++ *statusp = RCU_KTHREAD_WAITING;
++ return;
++ }
+ }
+- invoke_rcu_callbacks_kthread();
++ *statusp = RCU_KTHREAD_YIELDING;
++ trace_rcu_utilization(TPS("Start CPU kthread@rcu_yield"));
++ schedule_timeout_interruptible(2);
++ trace_rcu_utilization(TPS("End CPU kthread@rcu_yield"));
++ *statusp = RCU_KTHREAD_WAITING;
+ }
+
+-static void invoke_rcu_core(void)
++static struct smp_hotplug_thread rcu_cpu_thread_spec = {
++ .store = &rcu_cpu_kthread_task,
++ .thread_should_run = rcu_cpu_kthread_should_run,
++ .thread_fn = rcu_cpu_kthread,
++ .thread_comm = "rcuc/%u",
++ .setup = rcu_cpu_kthread_setup,
++ .park = rcu_cpu_kthread_park,
++};
++
++/*
++ * Spawn per-CPU RCU core processing kthreads.
++ */
++static int __init rcu_spawn_core_kthreads(void)
+ {
+- if (cpu_online(smp_processor_id()))
+- raise_softirq(RCU_SOFTIRQ);
++ int cpu;
++
++ for_each_possible_cpu(cpu)
++ per_cpu(rcu_cpu_has_work, cpu) = 0;
++ BUG_ON(smpboot_register_percpu_thread(&rcu_cpu_thread_spec));
++ return 0;
+ }
++early_initcall(rcu_spawn_core_kthreads);
+
+ /*
+ * Handle any core-RCU processing required by a call_rcu() invocation.
+@@ -3192,6 +3311,7 @@
+ }
+ EXPORT_SYMBOL_GPL(call_rcu_sched);
+
++#ifndef CONFIG_PREEMPT_RT_FULL
+ /*
+ * Queue an RCU callback for invocation after a quicker grace period.
+ */
+@@ -3200,6 +3320,7 @@
+ __call_rcu(head, func, &rcu_bh_state, -1, 0);
+ }
+ EXPORT_SYMBOL_GPL(call_rcu_bh);
++#endif
+
+ /*
+ * Queue an RCU callback for lazy invocation after a grace period.
+@@ -3291,6 +3412,7 @@
+ }
+ EXPORT_SYMBOL_GPL(synchronize_sched);
+
++#ifndef CONFIG_PREEMPT_RT_FULL
+ /**
+ * synchronize_rcu_bh - wait until an rcu_bh grace period has elapsed.
+ *
+@@ -3317,6 +3439,7 @@
+ wait_rcu_gp(call_rcu_bh);
+ }
+ EXPORT_SYMBOL_GPL(synchronize_rcu_bh);
++#endif
+
+ /**
+ * get_state_synchronize_rcu - Snapshot current RCU state
+@@ -3695,6 +3818,7 @@
+ mutex_unlock(&rsp->barrier_mutex);
+ }
+
++#ifndef CONFIG_PREEMPT_RT_FULL
+ /**
+ * rcu_barrier_bh - Wait until all in-flight call_rcu_bh() callbacks complete.
+ */
+@@ -3703,6 +3827,7 @@
+ _rcu_barrier(&rcu_bh_state);
+ }
+ EXPORT_SYMBOL_GPL(rcu_barrier_bh);
++#endif
+
+ /**
+ * rcu_barrier_sched - Wait for in-flight call_rcu_sched() callbacks.
+@@ -4196,12 +4321,13 @@
+
+ rcu_bootup_announce();
+ rcu_init_geometry();
++#ifndef CONFIG_PREEMPT_RT_FULL
+ rcu_init_one(&rcu_bh_state);
++#endif
+ rcu_init_one(&rcu_sched_state);
+ if (dump_tree)
+ rcu_dump_rcu_node_tree(&rcu_sched_state);
+ __rcu_init_preempt();
+- open_softirq(RCU_SOFTIRQ, rcu_process_callbacks);
+
+ /*
+ * We don't need protection against CPU-hotplug here because
+diff -Nur linux-4.8.15.orig/kernel/rcu/tree.h linux-4.8.15/kernel/rcu/tree.h
+--- linux-4.8.15.orig/kernel/rcu/tree.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/rcu/tree.h 2017-01-01 17:07:16.027426711 +0100
+@@ -587,18 +587,18 @@
+ */
+ extern struct rcu_state rcu_sched_state;
+
++#ifndef CONFIG_PREEMPT_RT_FULL
+ extern struct rcu_state rcu_bh_state;
++#endif
+
+ #ifdef CONFIG_PREEMPT_RCU
+ extern struct rcu_state rcu_preempt_state;
+ #endif /* #ifdef CONFIG_PREEMPT_RCU */
+
+-#ifdef CONFIG_RCU_BOOST
+ DECLARE_PER_CPU(unsigned int, rcu_cpu_kthread_status);
+ DECLARE_PER_CPU(int, rcu_cpu_kthread_cpu);
+ DECLARE_PER_CPU(unsigned int, rcu_cpu_kthread_loops);
+ DECLARE_PER_CPU(char, rcu_cpu_has_work);
+-#endif /* #ifdef CONFIG_RCU_BOOST */
+
+ #ifndef RCU_TREE_NONCORE
+
+@@ -618,10 +618,9 @@
+ static void __init __rcu_init_preempt(void);
+ static void rcu_initiate_boost(struct rcu_node *rnp, unsigned long flags);
+ static void rcu_preempt_boost_start_gp(struct rcu_node *rnp);
+-static void invoke_rcu_callbacks_kthread(void);
+ static bool rcu_is_callbacks_kthread(void);
++static void rcu_cpu_kthread_setup(unsigned int cpu);
+ #ifdef CONFIG_RCU_BOOST
+-static void rcu_preempt_do_callbacks(void);
+ static int rcu_spawn_one_boost_kthread(struct rcu_state *rsp,
+ struct rcu_node *rnp);
+ #endif /* #ifdef CONFIG_RCU_BOOST */
+diff -Nur linux-4.8.15.orig/kernel/rcu/tree_plugin.h linux-4.8.15/kernel/rcu/tree_plugin.h
+--- linux-4.8.15.orig/kernel/rcu/tree_plugin.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/rcu/tree_plugin.h 2017-01-01 17:07:16.031426957 +0100
+@@ -24,25 +24,10 @@
+ * Paul E. McKenney <paulmck@linux.vnet.ibm.com>
+ */
+
+-#include <linux/delay.h>
+-#include <linux/gfp.h>
+-#include <linux/oom.h>
+-#include <linux/smpboot.h>
+-#include "../time/tick-internal.h"
+-
+ #ifdef CONFIG_RCU_BOOST
+
+ #include "../locking/rtmutex_common.h"
+
+-/*
+- * Control variables for per-CPU and per-rcu_node kthreads. These
+- * handle all flavors of RCU.
+- */
+-static DEFINE_PER_CPU(struct task_struct *, rcu_cpu_kthread_task);
+-DEFINE_PER_CPU(unsigned int, rcu_cpu_kthread_status);
+-DEFINE_PER_CPU(unsigned int, rcu_cpu_kthread_loops);
+-DEFINE_PER_CPU(char, rcu_cpu_has_work);
+-
+ #else /* #ifdef CONFIG_RCU_BOOST */
+
+ /*
+@@ -55,6 +40,14 @@
+
+ #endif /* #else #ifdef CONFIG_RCU_BOOST */
+
++/*
++ * Control variables for per-CPU and per-rcu_node kthreads. These
++ * handle all flavors of RCU.
++ */
++DEFINE_PER_CPU(unsigned int, rcu_cpu_kthread_status);
++DEFINE_PER_CPU(unsigned int, rcu_cpu_kthread_loops);
++DEFINE_PER_CPU(char, rcu_cpu_has_work);
++
+ #ifdef CONFIG_RCU_NOCB_CPU
+ static cpumask_var_t rcu_nocb_mask; /* CPUs to have callbacks offloaded. */
+ static bool have_rcu_nocb_mask; /* Was rcu_nocb_mask allocated? */
+@@ -426,7 +419,7 @@
+ }
+
+ /* Hardware IRQ handlers cannot block, complain if they get here. */
+- if (in_irq() || in_serving_softirq()) {
++ if (preempt_count() & (HARDIRQ_MASK | SOFTIRQ_OFFSET)) {
+ lockdep_rcu_suspicious(__FILE__, __LINE__,
+ "rcu_read_unlock() from irq or softirq with blocking in critical section!!!\n");
+ pr_alert("->rcu_read_unlock_special: %#x (b: %d, enq: %d nq: %d)\n",
+@@ -632,15 +625,6 @@
+ t->rcu_read_unlock_special.b.need_qs = true;
+ }
+
+-#ifdef CONFIG_RCU_BOOST
+-
+-static void rcu_preempt_do_callbacks(void)
+-{
+- rcu_do_batch(rcu_state_p, this_cpu_ptr(rcu_data_p));
+-}
+-
+-#endif /* #ifdef CONFIG_RCU_BOOST */
+-
+ /*
+ * Queue a preemptible-RCU callback for invocation after a grace period.
+ */
+@@ -829,6 +813,19 @@
+
+ #endif /* #else #ifdef CONFIG_PREEMPT_RCU */
+
++/*
++ * If boosting, set rcuc kthreads to realtime priority.
++ */
++static void rcu_cpu_kthread_setup(unsigned int cpu)
++{
++#ifdef CONFIG_RCU_BOOST
++ struct sched_param sp;
++
++ sp.sched_priority = kthread_prio;
++ sched_setscheduler_nocheck(current, SCHED_FIFO, &sp);
++#endif /* #ifdef CONFIG_RCU_BOOST */
++}
++
+ #ifdef CONFIG_RCU_BOOST
+
+ #include "../locking/rtmutex_common.h"
+@@ -860,16 +857,6 @@
+
+ #endif /* #else #ifdef CONFIG_RCU_TRACE */
+
+-static void rcu_wake_cond(struct task_struct *t, int status)
+-{
+- /*
+- * If the thread is yielding, only wake it when this
+- * is invoked from idle
+- */
+- if (status != RCU_KTHREAD_YIELDING || is_idle_task(current))
+- wake_up_process(t);
+-}
+-
+ /*
+ * Carry out RCU priority boosting on the task indicated by ->exp_tasks
+ * or ->boost_tasks, advancing the pointer to the next task in the
+@@ -1013,23 +1000,6 @@
+ }
+
+ /*
+- * Wake up the per-CPU kthread to invoke RCU callbacks.
+- */
+-static void invoke_rcu_callbacks_kthread(void)
+-{
+- unsigned long flags;
+-
+- local_irq_save(flags);
+- __this_cpu_write(rcu_cpu_has_work, 1);
+- if (__this_cpu_read(rcu_cpu_kthread_task) != NULL &&
+- current != __this_cpu_read(rcu_cpu_kthread_task)) {
+- rcu_wake_cond(__this_cpu_read(rcu_cpu_kthread_task),
+- __this_cpu_read(rcu_cpu_kthread_status));
+- }
+- local_irq_restore(flags);
+-}
+-
+-/*
+ * Is the current CPU running the RCU-callbacks kthread?
+ * Caller must have preemption disabled.
+ */
+@@ -1083,67 +1053,6 @@
+ return 0;
+ }
+
+-static void rcu_kthread_do_work(void)
+-{
+- rcu_do_batch(&rcu_sched_state, this_cpu_ptr(&rcu_sched_data));
+- rcu_do_batch(&rcu_bh_state, this_cpu_ptr(&rcu_bh_data));
+- rcu_preempt_do_callbacks();
+-}
+-
+-static void rcu_cpu_kthread_setup(unsigned int cpu)
+-{
+- struct sched_param sp;
+-
+- sp.sched_priority = kthread_prio;
+- sched_setscheduler_nocheck(current, SCHED_FIFO, &sp);
+-}
+-
+-static void rcu_cpu_kthread_park(unsigned int cpu)
+-{
+- per_cpu(rcu_cpu_kthread_status, cpu) = RCU_KTHREAD_OFFCPU;
+-}
+-
+-static int rcu_cpu_kthread_should_run(unsigned int cpu)
+-{
+- return __this_cpu_read(rcu_cpu_has_work);
+-}
+-
+-/*
+- * Per-CPU kernel thread that invokes RCU callbacks. This replaces the
+- * RCU softirq used in flavors and configurations of RCU that do not
+- * support RCU priority boosting.
+- */
+-static void rcu_cpu_kthread(unsigned int cpu)
+-{
+- unsigned int *statusp = this_cpu_ptr(&rcu_cpu_kthread_status);
+- char work, *workp = this_cpu_ptr(&rcu_cpu_has_work);
+- int spincnt;
+-
+- for (spincnt = 0; spincnt < 10; spincnt++) {
+- trace_rcu_utilization(TPS("Start CPU kthread@rcu_wait"));
+- local_bh_disable();
+- *statusp = RCU_KTHREAD_RUNNING;
+- this_cpu_inc(rcu_cpu_kthread_loops);
+- local_irq_disable();
+- work = *workp;
+- *workp = 0;
+- local_irq_enable();
+- if (work)
+- rcu_kthread_do_work();
+- local_bh_enable();
+- if (*workp == 0) {
+- trace_rcu_utilization(TPS("End CPU kthread@rcu_wait"));
+- *statusp = RCU_KTHREAD_WAITING;
+- return;
+- }
+- }
+- *statusp = RCU_KTHREAD_YIELDING;
+- trace_rcu_utilization(TPS("Start CPU kthread@rcu_yield"));
+- schedule_timeout_interruptible(2);
+- trace_rcu_utilization(TPS("End CPU kthread@rcu_yield"));
+- *statusp = RCU_KTHREAD_WAITING;
+-}
+-
+ /*
+ * Set the per-rcu_node kthread's affinity to cover all CPUs that are
+ * served by the rcu_node in question. The CPU hotplug lock is still
+@@ -1174,26 +1083,12 @@
+ free_cpumask_var(cm);
+ }
+
+-static struct smp_hotplug_thread rcu_cpu_thread_spec = {
+- .store = &rcu_cpu_kthread_task,
+- .thread_should_run = rcu_cpu_kthread_should_run,
+- .thread_fn = rcu_cpu_kthread,
+- .thread_comm = "rcuc/%u",
+- .setup = rcu_cpu_kthread_setup,
+- .park = rcu_cpu_kthread_park,
+-};
+-
+ /*
+ * Spawn boost kthreads -- called as soon as the scheduler is running.
+ */
+ static void __init rcu_spawn_boost_kthreads(void)
+ {
+ struct rcu_node *rnp;
+- int cpu;
+-
+- for_each_possible_cpu(cpu)
+- per_cpu(rcu_cpu_has_work, cpu) = 0;
+- BUG_ON(smpboot_register_percpu_thread(&rcu_cpu_thread_spec));
+ rcu_for_each_leaf_node(rcu_state_p, rnp)
+ (void)rcu_spawn_one_boost_kthread(rcu_state_p, rnp);
+ }
+@@ -1216,11 +1111,6 @@
+ raw_spin_unlock_irqrestore_rcu_node(rnp, flags);
+ }
+
+-static void invoke_rcu_callbacks_kthread(void)
+-{
+- WARN_ON_ONCE(1);
+-}
+-
+ static bool rcu_is_callbacks_kthread(void)
+ {
+ return false;
+@@ -1244,7 +1134,7 @@
+
+ #endif /* #else #ifdef CONFIG_RCU_BOOST */
+
+-#if !defined(CONFIG_RCU_FAST_NO_HZ)
++#if !defined(CONFIG_RCU_FAST_NO_HZ) || defined(CONFIG_PREEMPT_RT_FULL)
+
+ /*
+ * Check to see if any future RCU-related work will need to be done
+@@ -1261,7 +1151,9 @@
+ return IS_ENABLED(CONFIG_RCU_NOCB_CPU_ALL)
+ ? 0 : rcu_cpu_has_callbacks(NULL);
+ }
++#endif /* !defined(CONFIG_RCU_FAST_NO_HZ) || defined(CONFIG_PREEMPT_RT_FULL) */
+
++#if !defined(CONFIG_RCU_FAST_NO_HZ)
+ /*
+ * Because we do not have RCU_FAST_NO_HZ, don't bother cleaning up
+ * after it.
+@@ -1357,6 +1249,8 @@
+ return cbs_ready;
+ }
+
++#ifndef CONFIG_PREEMPT_RT_FULL
++
+ /*
+ * Allow the CPU to enter dyntick-idle mode unless it has callbacks ready
+ * to invoke. If the CPU has callbacks, try to advance them. Tell the
+@@ -1402,6 +1296,7 @@
+ *nextevt = basemono + dj * TICK_NSEC;
+ return 0;
+ }
++#endif /* #ifndef CONFIG_PREEMPT_RT_FULL */
+
+ /*
+ * Prepare a CPU for idle from an RCU perspective. The first major task
+diff -Nur linux-4.8.15.orig/kernel/rcu/update.c linux-4.8.15/kernel/rcu/update.c
+--- linux-4.8.15.orig/kernel/rcu/update.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/rcu/update.c 2017-01-01 17:07:16.031426957 +0100
+@@ -63,7 +63,7 @@
+ #ifndef CONFIG_TINY_RCU
+ module_param(rcu_expedited, int, 0);
+ module_param(rcu_normal, int, 0);
+-static int rcu_normal_after_boot;
++static int rcu_normal_after_boot = IS_ENABLED(CONFIG_PREEMPT_RT_FULL);
+ module_param(rcu_normal_after_boot, int, 0);
+ #endif /* #ifndef CONFIG_TINY_RCU */
+
+@@ -130,8 +130,7 @@
+ }
+ EXPORT_SYMBOL_GPL(rcu_gp_is_normal);
+
+-static atomic_t rcu_expedited_nesting =
+- ATOMIC_INIT(IS_ENABLED(CONFIG_RCU_EXPEDITE_BOOT) ? 1 : 0);
++static atomic_t rcu_expedited_nesting = ATOMIC_INIT(1);
+
+ /*
+ * Should normal grace-period primitives be expedited? Intended for
+@@ -179,8 +178,7 @@
+ */
+ void rcu_end_inkernel_boot(void)
+ {
+- if (IS_ENABLED(CONFIG_RCU_EXPEDITE_BOOT))
+- rcu_unexpedite_gp();
++ rcu_unexpedite_gp();
+ if (rcu_normal_after_boot)
+ WRITE_ONCE(rcu_normal, 1);
+ }
+@@ -295,6 +293,7 @@
+ }
+ EXPORT_SYMBOL_GPL(rcu_read_lock_held);
+
++#ifndef CONFIG_PREEMPT_RT_FULL
+ /**
+ * rcu_read_lock_bh_held() - might we be in RCU-bh read-side critical section?
+ *
+@@ -321,6 +320,7 @@
+ return in_softirq() || irqs_disabled();
+ }
+ EXPORT_SYMBOL_GPL(rcu_read_lock_bh_held);
++#endif
+
+ #endif /* #ifdef CONFIG_DEBUG_LOCK_ALLOC */
+
+diff -Nur linux-4.8.15.orig/kernel/relay.c linux-4.8.15/kernel/relay.c
+--- linux-4.8.15.orig/kernel/relay.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/relay.c 2017-01-01 17:07:16.031426957 +0100
+@@ -336,6 +336,10 @@
+ {
+ struct rchan_buf *buf = (struct rchan_buf *)data;
+ wake_up_interruptible(&buf->read_wait);
++ /*
++ * Stupid polling for now:
++ */
++ mod_timer(&buf->timer, jiffies + 1);
+ }
+
+ /**
+@@ -353,6 +357,7 @@
+ init_waitqueue_head(&buf->read_wait);
+ kref_init(&buf->kref);
+ setup_timer(&buf->timer, wakeup_readers, (unsigned long)buf);
++ mod_timer(&buf->timer, jiffies + 1);
+ } else
+ del_timer_sync(&buf->timer);
+
+@@ -767,15 +772,6 @@
+ else
+ buf->early_bytes += buf->chan->subbuf_size -
+ buf->padding[old_subbuf];
+- smp_mb();
+- if (waitqueue_active(&buf->read_wait))
+- /*
+- * Calling wake_up_interruptible() from here
+- * will deadlock if we happen to be logging
+- * from the scheduler (trying to re-grab
+- * rq->lock), so defer it.
+- */
+- mod_timer(&buf->timer, jiffies + 1);
+ }
+
+ old = buf->data;
+diff -Nur linux-4.8.15.orig/kernel/sched/completion.c linux-4.8.15/kernel/sched/completion.c
+--- linux-4.8.15.orig/kernel/sched/completion.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/sched/completion.c 2017-01-01 17:07:16.031426957 +0100
+@@ -30,10 +30,10 @@
+ {
+ unsigned long flags;
+
+- spin_lock_irqsave(&x->wait.lock, flags);
++ raw_spin_lock_irqsave(&x->wait.lock, flags);
+ x->done++;
+- __wake_up_locked(&x->wait, TASK_NORMAL, 1);
+- spin_unlock_irqrestore(&x->wait.lock, flags);
++ swake_up_locked(&x->wait);
++ raw_spin_unlock_irqrestore(&x->wait.lock, flags);
+ }
+ EXPORT_SYMBOL(complete);
+
+@@ -50,10 +50,10 @@
+ {
+ unsigned long flags;
+
+- spin_lock_irqsave(&x->wait.lock, flags);
++ raw_spin_lock_irqsave(&x->wait.lock, flags);
+ x->done += UINT_MAX/2;
+- __wake_up_locked(&x->wait, TASK_NORMAL, 0);
+- spin_unlock_irqrestore(&x->wait.lock, flags);
++ swake_up_all_locked(&x->wait);
++ raw_spin_unlock_irqrestore(&x->wait.lock, flags);
+ }
+ EXPORT_SYMBOL(complete_all);
+
+@@ -62,20 +62,20 @@
+ long (*action)(long), long timeout, int state)
+ {
+ if (!x->done) {
+- DECLARE_WAITQUEUE(wait, current);
++ DECLARE_SWAITQUEUE(wait);
+
+- __add_wait_queue_tail_exclusive(&x->wait, &wait);
++ __prepare_to_swait(&x->wait, &wait);
+ do {
+ if (signal_pending_state(state, current)) {
+ timeout = -ERESTARTSYS;
+ break;
+ }
+ __set_current_state(state);
+- spin_unlock_irq(&x->wait.lock);
++ raw_spin_unlock_irq(&x->wait.lock);
+ timeout = action(timeout);
+- spin_lock_irq(&x->wait.lock);
++ raw_spin_lock_irq(&x->wait.lock);
+ } while (!x->done && timeout);
+- __remove_wait_queue(&x->wait, &wait);
++ __finish_swait(&x->wait, &wait);
+ if (!x->done)
+ return timeout;
+ }
+@@ -89,9 +89,9 @@
+ {
+ might_sleep();
+
+- spin_lock_irq(&x->wait.lock);
++ raw_spin_lock_irq(&x->wait.lock);
+ timeout = do_wait_for_common(x, action, timeout, state);
+- spin_unlock_irq(&x->wait.lock);
++ raw_spin_unlock_irq(&x->wait.lock);
+ return timeout;
+ }
+
+@@ -277,12 +277,12 @@
+ if (!READ_ONCE(x->done))
+ return 0;
+
+- spin_lock_irqsave(&x->wait.lock, flags);
++ raw_spin_lock_irqsave(&x->wait.lock, flags);
+ if (!x->done)
+ ret = 0;
+ else
+ x->done--;
+- spin_unlock_irqrestore(&x->wait.lock, flags);
++ raw_spin_unlock_irqrestore(&x->wait.lock, flags);
+ return ret;
+ }
+ EXPORT_SYMBOL(try_wait_for_completion);
+@@ -311,7 +311,7 @@
+ * after it's acquired the lock.
+ */
+ smp_rmb();
+- spin_unlock_wait(&x->wait.lock);
++ raw_spin_unlock_wait(&x->wait.lock);
+ return true;
+ }
+ EXPORT_SYMBOL(completion_done);
+diff -Nur linux-4.8.15.orig/kernel/sched/core.c linux-4.8.15/kernel/sched/core.c
+--- linux-4.8.15.orig/kernel/sched/core.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/sched/core.c 2017-01-01 17:07:16.035427212 +0100
+@@ -129,7 +129,11 @@
+ * Number of tasks to iterate in a single balance run.
+ * Limited because this is done with IRQs disabled.
+ */
++#ifndef CONFIG_PREEMPT_RT_FULL
+ const_debug unsigned int sysctl_sched_nr_migrate = 32;
++#else
++const_debug unsigned int sysctl_sched_nr_migrate = 8;
++#endif
+
+ /*
+ * period over which we average the RT time consumption, measured
+@@ -345,6 +349,7 @@
+
+ hrtimer_init(&rq->hrtick_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+ rq->hrtick_timer.function = hrtick;
++ rq->hrtick_timer.irqsafe = 1;
+ }
+ #else /* CONFIG_SCHED_HRTICK */
+ static inline void hrtick_clear(struct rq *rq)
+@@ -449,7 +454,7 @@
+ head->lastp = &node->next;
+ }
+
+-void wake_up_q(struct wake_q_head *head)
++void __wake_up_q(struct wake_q_head *head, bool sleeper)
+ {
+ struct wake_q_node *node = head->first;
+
+@@ -466,7 +471,10 @@
+ * wake_up_process() implies a wmb() to pair with the queueing
+ * in wake_q_add() so as not to miss wakeups.
+ */
+- wake_up_process(task);
++ if (sleeper)
++ wake_up_lock_sleeper(task);
++ else
++ wake_up_process(task);
+ put_task_struct(task);
+ }
+ }
+@@ -502,6 +510,38 @@
+ trace_sched_wake_idle_without_ipi(cpu);
+ }
+
++#ifdef CONFIG_PREEMPT_LAZY
++void resched_curr_lazy(struct rq *rq)
++{
++ struct task_struct *curr = rq->curr;
++ int cpu;
++
++ if (!sched_feat(PREEMPT_LAZY)) {
++ resched_curr(rq);
++ return;
++ }
++
++ lockdep_assert_held(&rq->lock);
++
++ if (test_tsk_need_resched(curr))
++ return;
++
++ if (test_tsk_need_resched_lazy(curr))
++ return;
++
++ set_tsk_need_resched_lazy(curr);
++
++ cpu = cpu_of(rq);
++ if (cpu == smp_processor_id())
++ return;
++
++ /* NEED_RESCHED_LAZY must be visible before we test polling */
++ smp_mb();
++ if (!tsk_is_polling(curr))
++ smp_send_reschedule(cpu);
++}
++#endif
++
+ void resched_cpu(int cpu)
+ {
+ struct rq *rq = cpu_rq(cpu);
+@@ -525,11 +565,14 @@
+ */
+ int get_nohz_timer_target(void)
+ {
+- int i, cpu = smp_processor_id();
++ int i, cpu;
+ struct sched_domain *sd;
+
++ preempt_disable_rt();
++ cpu = smp_processor_id();
++
+ if (!idle_cpu(cpu) && is_housekeeping_cpu(cpu))
+- return cpu;
++ goto preempt_en_rt;
+
+ rcu_read_lock();
+ for_each_domain(cpu, sd) {
+@@ -548,6 +591,8 @@
+ cpu = housekeeping_any_cpu();
+ unlock:
+ rcu_read_unlock();
++preempt_en_rt:
++ preempt_enable_rt();
+ return cpu;
+ }
+ /*
+@@ -1089,6 +1134,11 @@
+
+ lockdep_assert_held(&p->pi_lock);
+
++ if (__migrate_disabled(p)) {
++ cpumask_copy(&p->cpus_allowed, new_mask);
++ return;
++ }
++
+ queued = task_on_rq_queued(p);
+ running = task_current(rq, p);
+
+@@ -1111,6 +1161,84 @@
+ enqueue_task(rq, p, ENQUEUE_RESTORE);
+ }
+
++static DEFINE_PER_CPU(struct cpumask, sched_cpumasks);
++static DEFINE_MUTEX(sched_down_mutex);
++static cpumask_t sched_down_cpumask;
++
++void tell_sched_cpu_down_begin(int cpu)
++{
++ mutex_lock(&sched_down_mutex);
++ cpumask_set_cpu(cpu, &sched_down_cpumask);
++ mutex_unlock(&sched_down_mutex);
++}
++
++void tell_sched_cpu_down_done(int cpu)
++{
++ mutex_lock(&sched_down_mutex);
++ cpumask_clear_cpu(cpu, &sched_down_cpumask);
++ mutex_unlock(&sched_down_mutex);
++}
++
++/**
++ * migrate_me - try to move the current task off this cpu
++ *
++ * Used by the pin_current_cpu() code to try to get tasks
++ * to move off the current CPU as it is going down.
++ * It will only move the task if the task isn't pinned to
++ * the CPU (with migrate_disable, affinity or NO_SETAFFINITY)
++ * and the task has to be in a RUNNING state. Otherwise the
++ * movement of the task will wake it up (change its state
++ * to running) when the task did not expect it.
++ *
++ * Returns 1 if it succeeded in moving the current task
++ * 0 otherwise.
++ */
++int migrate_me(void)
++{
++ struct task_struct *p = current;
++ struct migration_arg arg;
++ struct cpumask *cpumask;
++ struct cpumask *mask;
++ unsigned int dest_cpu;
++ struct rq_flags rf;
++ struct rq *rq;
++
++ /*
++ * We can not migrate tasks bounded to a CPU or tasks not
++ * running. The movement of the task will wake it up.
++ */
++ if (p->flags & PF_NO_SETAFFINITY || p->state)
++ return 0;
++
++ mutex_lock(&sched_down_mutex);
++ rq = task_rq_lock(p, &rf);
++
++ cpumask = this_cpu_ptr(&sched_cpumasks);
++ mask = &p->cpus_allowed;
++
++ cpumask_andnot(cpumask, mask, &sched_down_cpumask);
++
++ if (!cpumask_weight(cpumask)) {
++ /* It's only on this CPU? */
++ task_rq_unlock(rq, p, &rf);
++ mutex_unlock(&sched_down_mutex);
++ return 0;
++ }
++
++ dest_cpu = cpumask_any_and(cpu_active_mask, cpumask);
++
++ arg.task = p;
++ arg.dest_cpu = dest_cpu;
++
++ task_rq_unlock(rq, p, &rf);
++
++ stop_one_cpu(cpu_of(rq), migration_cpu_stop, &arg);
++ tlb_migrate_finish(p->mm);
++ mutex_unlock(&sched_down_mutex);
++
++ return 1;
++}
++
+ /*
+ * Change a given task's CPU affinity. Migrate the thread to a
+ * proper CPU and schedule it away if the CPU it's executing on
+@@ -1168,7 +1296,7 @@
+ }
+
+ /* Can the task run on the task's current CPU? If so, we're done */
+- if (cpumask_test_cpu(task_cpu(p), new_mask))
++ if (cpumask_test_cpu(task_cpu(p), new_mask) || __migrate_disabled(p))
+ goto out;
+
+ dest_cpu = cpumask_any_and(cpu_valid_mask, new_mask);
+@@ -1355,6 +1483,18 @@
+ return ret;
+ }
+
++static bool check_task_state(struct task_struct *p, long match_state)
++{
++ bool match = false;
++
++ raw_spin_lock_irq(&p->pi_lock);
++ if (p->state == match_state || p->saved_state == match_state)
++ match = true;
++ raw_spin_unlock_irq(&p->pi_lock);
++
++ return match;
++}
++
+ /*
+ * wait_task_inactive - wait for a thread to unschedule.
+ *
+@@ -1399,7 +1539,7 @@
+ * is actually now running somewhere else!
+ */
+ while (task_running(rq, p)) {
+- if (match_state && unlikely(p->state != match_state))
++ if (match_state && !check_task_state(p, match_state))
+ return 0;
+ cpu_relax();
+ }
+@@ -1414,7 +1554,8 @@
+ running = task_running(rq, p);
+ queued = task_on_rq_queued(p);
+ ncsw = 0;
+- if (!match_state || p->state == match_state)
++ if (!match_state || p->state == match_state ||
++ p->saved_state == match_state)
+ ncsw = p->nvcsw | LONG_MIN; /* sets MSB */
+ task_rq_unlock(rq, p, &rf);
+
+@@ -1670,10 +1811,6 @@
+ {
+ activate_task(rq, p, en_flags);
+ p->on_rq = TASK_ON_RQ_QUEUED;
+-
+- /* if a worker is waking up, notify workqueue */
+- if (p->flags & PF_WQ_WORKER)
+- wq_worker_waking_up(p, cpu_of(rq));
+ }
+
+ /*
+@@ -2008,8 +2145,27 @@
+ */
+ smp_mb__before_spinlock();
+ raw_spin_lock_irqsave(&p->pi_lock, flags);
+- if (!(p->state & state))
++ if (!(p->state & state)) {
++ /*
++ * The task might be running due to a spinlock sleeper
++ * wakeup. Check the saved state and set it to running
++ * if the wakeup condition is true.
++ */
++ if (!(wake_flags & WF_LOCK_SLEEPER)) {
++ if (p->saved_state & state) {
++ p->saved_state = TASK_RUNNING;
++ success = 1;
++ }
++ }
+ goto out;
++ }
++
++ /*
++ * If this is a regular wakeup, then we can unconditionally
++ * clear the saved state of a "lock sleeper".
++ */
++ if (!(wake_flags & WF_LOCK_SLEEPER))
++ p->saved_state = TASK_RUNNING;
+
+ trace_sched_waking(p);
+
+@@ -2093,53 +2249,6 @@
+ }
+
+ /**
+- * try_to_wake_up_local - try to wake up a local task with rq lock held
+- * @p: the thread to be awakened
+- *
+- * Put @p on the run-queue if it's not already there. The caller must
+- * ensure that this_rq() is locked, @p is bound to this_rq() and not
+- * the current task.
+- */
+-static void try_to_wake_up_local(struct task_struct *p, struct pin_cookie cookie)
+-{
+- struct rq *rq = task_rq(p);
+-
+- if (WARN_ON_ONCE(rq != this_rq()) ||
+- WARN_ON_ONCE(p == current))
+- return;
+-
+- lockdep_assert_held(&rq->lock);
+-
+- if (!raw_spin_trylock(&p->pi_lock)) {
+- /*
+- * This is OK, because current is on_cpu, which avoids it being
+- * picked for load-balance and preemption/IRQs are still
+- * disabled avoiding further scheduler activity on it and we've
+- * not yet picked a replacement task.
+- */
+- lockdep_unpin_lock(&rq->lock, cookie);
+- raw_spin_unlock(&rq->lock);
+- raw_spin_lock(&p->pi_lock);
+- raw_spin_lock(&rq->lock);
+- lockdep_repin_lock(&rq->lock, cookie);
+- }
+-
+- if (!(p->state & TASK_NORMAL))
+- goto out;
+-
+- trace_sched_waking(p);
+-
+- if (!task_on_rq_queued(p))
+- ttwu_activate(rq, p, ENQUEUE_WAKEUP);
+-
+- ttwu_do_wakeup(rq, p, 0, cookie);
+- if (schedstat_enabled())
+- ttwu_stat(p, smp_processor_id(), 0);
+-out:
+- raw_spin_unlock(&p->pi_lock);
+-}
+-
+-/**
+ * wake_up_process - Wake up a specific process
+ * @p: The process to be woken up.
+ *
+@@ -2157,6 +2266,18 @@
+ }
+ EXPORT_SYMBOL(wake_up_process);
+
++/**
++ * wake_up_lock_sleeper - Wake up a specific process blocked on a "sleeping lock"
++ * @p: The process to be woken up.
++ *
++ * Same as wake_up_process() above, but wake_flags=WF_LOCK_SLEEPER to indicate
++ * the nature of the wakeup.
++ */
++int wake_up_lock_sleeper(struct task_struct *p)
++{
++ return try_to_wake_up(p, TASK_ALL, WF_LOCK_SLEEPER);
++}
++
+ int wake_up_state(struct task_struct *p, unsigned int state)
+ {
+ return try_to_wake_up(p, state, 0);
+@@ -2433,6 +2554,9 @@
+ p->on_cpu = 0;
+ #endif
+ init_task_preempt_count(p);
++#ifdef CONFIG_HAVE_PREEMPT_LAZY
++ task_thread_info(p)->preempt_lazy_count = 0;
++#endif
+ #ifdef CONFIG_SMP
+ plist_node_init(&p->pushable_tasks, MAX_PRIO);
+ RB_CLEAR_NODE(&p->pushable_dl_tasks);
+@@ -2761,8 +2885,12 @@
+ finish_arch_post_lock_switch();
+
+ fire_sched_in_preempt_notifiers(current);
++ /*
++ * We use mmdrop_delayed() here so we don't have to do the
++ * full __mmdrop() when we are the last user.
++ */
+ if (mm)
+- mmdrop(mm);
++ mmdrop_delayed(mm);
+ if (unlikely(prev_state == TASK_DEAD)) {
+ if (prev->sched_class->task_dead)
+ prev->sched_class->task_dead(prev);
+@@ -3237,6 +3365,77 @@
+ schedstat_inc(this_rq(), sched_count);
+ }
+
++#if defined(CONFIG_PREEMPT_RT_FULL) && defined(CONFIG_SMP)
++
++void migrate_disable(void)
++{
++ struct task_struct *p = current;
++
++ if (in_atomic() || irqs_disabled()) {
++#ifdef CONFIG_SCHED_DEBUG
++ p->migrate_disable_atomic++;
++#endif
++ return;
++ }
++
++#ifdef CONFIG_SCHED_DEBUG
++ if (unlikely(p->migrate_disable_atomic)) {
++ tracing_off();
++ WARN_ON_ONCE(1);
++ }
++#endif
++
++ if (p->migrate_disable) {
++ p->migrate_disable++;
++ return;
++ }
++
++ preempt_disable();
++ preempt_lazy_disable();
++ pin_current_cpu();
++ p->migrate_disable = 1;
++ preempt_enable();
++}
++EXPORT_SYMBOL(migrate_disable);
++
++void migrate_enable(void)
++{
++ struct task_struct *p = current;
++
++ if (in_atomic() || irqs_disabled()) {
++#ifdef CONFIG_SCHED_DEBUG
++ p->migrate_disable_atomic--;
++#endif
++ return;
++ }
++
++#ifdef CONFIG_SCHED_DEBUG
++ if (unlikely(p->migrate_disable_atomic)) {
++ tracing_off();
++ WARN_ON_ONCE(1);
++ }
++#endif
++ WARN_ON_ONCE(p->migrate_disable <= 0);
++
++ if (p->migrate_disable > 1) {
++ p->migrate_disable--;
++ return;
++ }
++
++ preempt_disable();
++ /*
++ * Clearing migrate_disable causes tsk_cpus_allowed to
++ * show the tasks original cpu affinity.
++ */
++ p->migrate_disable = 0;
++
++ unpin_current_cpu();
++ preempt_enable();
++ preempt_lazy_enable();
++}
++EXPORT_SYMBOL(migrate_enable);
++#endif
++
+ /*
+ * Pick up the highest-prio task:
+ */
+@@ -3364,19 +3563,6 @@
+ } else {
+ deactivate_task(rq, prev, DEQUEUE_SLEEP);
+ prev->on_rq = 0;
+-
+- /*
+- * If a worker went to sleep, notify and ask workqueue
+- * whether it wants to wake up a task to maintain
+- * concurrency.
+- */
+- if (prev->flags & PF_WQ_WORKER) {
+- struct task_struct *to_wakeup;
+-
+- to_wakeup = wq_worker_sleeping(prev);
+- if (to_wakeup)
+- try_to_wake_up_local(to_wakeup, cookie);
+- }
+ }
+ switch_count = &prev->nvcsw;
+ }
+@@ -3386,6 +3572,7 @@
+
+ next = pick_next_task(rq, prev, cookie);
+ clear_tsk_need_resched(prev);
++ clear_tsk_need_resched_lazy(prev);
+ clear_preempt_need_resched();
+ rq->clock_skip_update = 0;
+
+@@ -3407,9 +3594,20 @@
+
+ static inline void sched_submit_work(struct task_struct *tsk)
+ {
+- if (!tsk->state || tsk_is_pi_blocked(tsk))
++ if (!tsk->state)
+ return;
+ /*
++ * If a worker went to sleep, notify and ask workqueue whether
++ * it wants to wake up a task to maintain concurrency.
++ */
++ if (tsk->flags & PF_WQ_WORKER)
++ wq_worker_sleeping(tsk);
++
++
++ if (tsk_is_pi_blocked(tsk))
++ return;
++
++ /*
+ * If we are going to sleep and we have plugged IO queued,
+ * make sure to submit it to avoid deadlocks.
+ */
+@@ -3417,6 +3615,12 @@
+ blk_schedule_flush_plug(tsk);
+ }
+
++static void sched_update_worker(struct task_struct *tsk)
++{
++ if (tsk->flags & PF_WQ_WORKER)
++ wq_worker_running(tsk);
++}
++
+ asmlinkage __visible void __sched schedule(void)
+ {
+ struct task_struct *tsk = current;
+@@ -3427,6 +3631,7 @@
+ __schedule(false);
+ sched_preempt_enable_no_resched();
+ } while (need_resched());
++ sched_update_worker(tsk);
+ }
+ EXPORT_SYMBOL(schedule);
+
+@@ -3490,6 +3695,30 @@
+ } while (need_resched());
+ }
+
++#ifdef CONFIG_PREEMPT_LAZY
++/*
++ * If TIF_NEED_RESCHED is then we allow to be scheduled away since this is
++ * set by a RT task. Oterwise we try to avoid beeing scheduled out as long as
++ * preempt_lazy_count counter >0.
++ */
++static __always_inline int preemptible_lazy(void)
++{
++ if (test_thread_flag(TIF_NEED_RESCHED))
++ return 1;
++ if (current_thread_info()->preempt_lazy_count)
++ return 0;
++ return 1;
++}
++
++#else
++
++static inline int preemptible_lazy(void)
++{
++ return 1;
++}
++
++#endif
++
+ #ifdef CONFIG_PREEMPT
+ /*
+ * this is the entry point to schedule() from in-kernel preemption
+@@ -3504,7 +3733,8 @@
+ */
+ if (likely(!preemptible()))
+ return;
+-
++ if (!preemptible_lazy())
++ return;
+ preempt_schedule_common();
+ }
+ NOKPROBE_SYMBOL(preempt_schedule);
+@@ -3531,6 +3761,9 @@
+ if (likely(!preemptible()))
+ return;
+
++ if (!preemptible_lazy())
++ return;
++
+ do {
+ /*
+ * Because the function tracer can trace preempt_count_sub()
+@@ -3553,7 +3786,16 @@
+ * an infinite recursion.
+ */
+ prev_ctx = exception_enter();
++ /*
++ * The add/subtract must not be traced by the function
++ * tracer. But we still want to account for the
++ * preempt off latency tracer. Since the _notrace versions
++ * of add/subtract skip the accounting for latency tracer
++ * we must force it manually.
++ */
++ start_critical_timings();
+ __schedule(true);
++ stop_critical_timings();
+ exception_exit(prev_ctx);
+
+ preempt_latency_stop(1);
+@@ -4901,6 +5143,7 @@
+ }
+ EXPORT_SYMBOL(__cond_resched_lock);
+
++#ifndef CONFIG_PREEMPT_RT_FULL
+ int __sched __cond_resched_softirq(void)
+ {
+ BUG_ON(!in_softirq());
+@@ -4914,6 +5157,7 @@
+ return 0;
+ }
+ EXPORT_SYMBOL(__cond_resched_softirq);
++#endif
+
+ /**
+ * yield - yield the current processor to other threads.
+@@ -5283,7 +5527,9 @@
+
+ /* Set the preempt count _outside_ the spinlocks! */
+ init_idle_preempt_count(idle, cpu);
+-
++#ifdef CONFIG_HAVE_PREEMPT_LAZY
++ task_thread_info(idle)->preempt_lazy_count = 0;
++#endif
+ /*
+ * The idle tasks have their own, simple scheduling class:
+ */
+@@ -5426,6 +5672,8 @@
+ #endif /* CONFIG_NUMA_BALANCING */
+
+ #ifdef CONFIG_HOTPLUG_CPU
++static DEFINE_PER_CPU(struct mm_struct *, idle_last_mm);
++
+ /*
+ * Ensures that the idle task is using init_mm right before its cpu goes
+ * offline.
+@@ -5440,7 +5688,12 @@
+ switch_mm_irqs_off(mm, &init_mm, current);
+ finish_arch_post_lock_switch();
+ }
+- mmdrop(mm);
++ /*
++ * Defer the cleanup to an alive cpu. On RT we can neither
++ * call mmdrop() nor mmdrop_delayed() from here.
++ */
++ per_cpu(idle_last_mm, smp_processor_id()) = mm;
++
+ }
+
+ /*
+@@ -7315,6 +7568,10 @@
+ update_max_interval();
+ nohz_balance_exit_idle(cpu);
+ hrtick_clear(rq);
++ if (per_cpu(idle_last_mm, cpu)) {
++ mmdrop_delayed(per_cpu(idle_last_mm, cpu));
++ per_cpu(idle_last_mm, cpu) = NULL;
++ }
+ return 0;
+ }
+ #endif
+@@ -7566,7 +7823,7 @@
+ #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
+ static inline int preempt_count_equals(int preempt_offset)
+ {
+- int nested = preempt_count() + rcu_preempt_depth();
++ int nested = preempt_count() + sched_rcu_preempt_depth();
+
+ return (nested == preempt_offset);
+ }
+diff -Nur linux-4.8.15.orig/kernel/sched/deadline.c linux-4.8.15/kernel/sched/deadline.c
+--- linux-4.8.15.orig/kernel/sched/deadline.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/sched/deadline.c 2017-01-01 17:07:16.035427212 +0100
+@@ -697,6 +697,7 @@
+
+ hrtimer_init(timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+ timer->function = dl_task_timer;
++ timer->irqsafe = 1;
+ }
+
+ static
+diff -Nur linux-4.8.15.orig/kernel/sched/debug.c linux-4.8.15/kernel/sched/debug.c
+--- linux-4.8.15.orig/kernel/sched/debug.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/sched/debug.c 2017-01-01 17:07:16.035427212 +0100
+@@ -552,6 +552,9 @@
+ P(rt_throttled);
+ PN(rt_time);
+ PN(rt_runtime);
++#ifdef CONFIG_SMP
++ P(rt_nr_migratory);
++#endif
+
+ #undef PN
+ #undef P
+@@ -947,6 +950,10 @@
+ #endif
+ P(policy);
+ P(prio);
++#ifdef CONFIG_PREEMPT_RT_FULL
++ P(migrate_disable);
++#endif
++ P(nr_cpus_allowed);
+ #undef PN
+ #undef __PN
+ #undef P
+diff -Nur linux-4.8.15.orig/kernel/sched/fair.c linux-4.8.15/kernel/sched/fair.c
+--- linux-4.8.15.orig/kernel/sched/fair.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/sched/fair.c 2017-01-01 17:07:16.039427472 +0100
+@@ -3508,7 +3508,7 @@
+ ideal_runtime = sched_slice(cfs_rq, curr);
+ delta_exec = curr->sum_exec_runtime - curr->prev_sum_exec_runtime;
+ if (delta_exec > ideal_runtime) {
+- resched_curr(rq_of(cfs_rq));
++ resched_curr_lazy(rq_of(cfs_rq));
+ /*
+ * The current task ran long enough, ensure it doesn't get
+ * re-elected due to buddy favours.
+@@ -3532,7 +3532,7 @@
+ return;
+
+ if (delta > ideal_runtime)
+- resched_curr(rq_of(cfs_rq));
++ resched_curr_lazy(rq_of(cfs_rq));
+ }
+
+ static void
+@@ -3677,7 +3677,7 @@
+ * validating it and just reschedule.
+ */
+ if (queued) {
+- resched_curr(rq_of(cfs_rq));
++ resched_curr_lazy(rq_of(cfs_rq));
+ return;
+ }
+ /*
+@@ -3859,7 +3859,7 @@
+ * hierarchy can be throttled
+ */
+ if (!assign_cfs_rq_runtime(cfs_rq) && likely(cfs_rq->curr))
+- resched_curr(rq_of(cfs_rq));
++ resched_curr_lazy(rq_of(cfs_rq));
+ }
+
+ static __always_inline
+@@ -4487,7 +4487,7 @@
+
+ if (delta < 0) {
+ if (rq->curr == p)
+- resched_curr(rq);
++ resched_curr_lazy(rq);
+ return;
+ }
+ hrtick_start(rq, delta);
+@@ -5676,7 +5676,7 @@
+ return;
+
+ preempt:
+- resched_curr(rq);
++ resched_curr_lazy(rq);
+ /*
+ * Only set the backward buddy when the current task is still
+ * on the rq. This can happen when a wakeup gets interleaved
+@@ -8402,7 +8402,7 @@
+ * 'current' within the tree based on its new key value.
+ */
+ swap(curr->vruntime, se->vruntime);
+- resched_curr(rq);
++ resched_curr_lazy(rq);
+ }
+
+ se->vruntime -= cfs_rq->min_vruntime;
+@@ -8426,7 +8426,7 @@
+ */
+ if (rq->curr == p) {
+ if (p->prio > oldprio)
+- resched_curr(rq);
++ resched_curr_lazy(rq);
+ } else
+ check_preempt_curr(rq, p, 0);
+ }
+diff -Nur linux-4.8.15.orig/kernel/sched/features.h linux-4.8.15/kernel/sched/features.h
+--- linux-4.8.15.orig/kernel/sched/features.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/sched/features.h 2017-01-01 17:07:16.039427472 +0100
+@@ -45,11 +45,19 @@
+ */
+ SCHED_FEAT(NONTASK_CAPACITY, true)
+
++#ifdef CONFIG_PREEMPT_RT_FULL
++SCHED_FEAT(TTWU_QUEUE, false)
++# ifdef CONFIG_PREEMPT_LAZY
++SCHED_FEAT(PREEMPT_LAZY, true)
++# endif
++#else
++
+ /*
+ * Queue remote wakeups on the target CPU and process them
+ * using the scheduler IPI. Reduces rq->lock contention/bounces.
+ */
+ SCHED_FEAT(TTWU_QUEUE, true)
++#endif
+
+ #ifdef HAVE_RT_PUSH_IPI
+ /*
+diff -Nur linux-4.8.15.orig/kernel/sched/Makefile linux-4.8.15/kernel/sched/Makefile
+--- linux-4.8.15.orig/kernel/sched/Makefile 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/sched/Makefile 2017-01-01 17:07:16.031426957 +0100
+@@ -17,7 +17,7 @@
+
+ obj-y += core.o loadavg.o clock.o cputime.o
+ obj-y += idle_task.o fair.o rt.o deadline.o stop_task.o
+-obj-y += wait.o swait.o completion.o idle.o
++obj-y += wait.o swait.o swork.o completion.o idle.o
+ obj-$(CONFIG_SMP) += cpupri.o cpudeadline.o
+ obj-$(CONFIG_SCHED_AUTOGROUP) += auto_group.o
+ obj-$(CONFIG_SCHEDSTATS) += stats.o
+diff -Nur linux-4.8.15.orig/kernel/sched/rt.c linux-4.8.15/kernel/sched/rt.c
+--- linux-4.8.15.orig/kernel/sched/rt.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/sched/rt.c 2017-01-01 17:07:16.039427472 +0100
+@@ -47,6 +47,7 @@
+
+ hrtimer_init(&rt_b->rt_period_timer,
+ CLOCK_MONOTONIC, HRTIMER_MODE_REL);
++ rt_b->rt_period_timer.irqsafe = 1;
+ rt_b->rt_period_timer.function = sched_rt_period_timer;
+ }
+
+@@ -101,6 +102,7 @@
+ rt_rq->push_cpu = nr_cpu_ids;
+ raw_spin_lock_init(&rt_rq->push_lock);
+ init_irq_work(&rt_rq->push_work, push_irq_work_func);
++ rt_rq->push_work.flags |= IRQ_WORK_HARD_IRQ;
+ #endif
+ #endif /* CONFIG_SMP */
+ /* We start is dequeued state, because no RT tasks are queued */
+diff -Nur linux-4.8.15.orig/kernel/sched/sched.h linux-4.8.15/kernel/sched/sched.h
+--- linux-4.8.15.orig/kernel/sched/sched.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/sched/sched.h 2017-01-01 17:07:16.039427472 +0100
+@@ -1138,6 +1138,7 @@
+ #define WF_SYNC 0x01 /* waker goes to sleep after wakeup */
+ #define WF_FORK 0x02 /* child wakeup after fork */
+ #define WF_MIGRATED 0x4 /* internal use, task got migrated */
++#define WF_LOCK_SLEEPER 0x08 /* wakeup spinlock "sleeper" */
+
+ /*
+ * To aid in avoiding the subversion of "niceness" due to uneven distribution
+@@ -1316,6 +1317,15 @@
+ extern void resched_curr(struct rq *rq);
+ extern void resched_cpu(int cpu);
+
++#ifdef CONFIG_PREEMPT_LAZY
++extern void resched_curr_lazy(struct rq *rq);
++#else
++static inline void resched_curr_lazy(struct rq *rq)
++{
++ resched_curr(rq);
++}
++#endif
++
+ extern struct rt_bandwidth def_rt_bandwidth;
+ extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime);
+
+diff -Nur linux-4.8.15.orig/kernel/sched/swait.c linux-4.8.15/kernel/sched/swait.c
+--- linux-4.8.15.orig/kernel/sched/swait.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/sched/swait.c 2017-01-01 17:07:16.039427472 +0100
+@@ -1,5 +1,6 @@
+ #include <linux/sched.h>
+ #include <linux/swait.h>
++#include <linux/suspend.h>
+
+ void __init_swait_queue_head(struct swait_queue_head *q, const char *name,
+ struct lock_class_key *key)
+@@ -29,6 +30,25 @@
+ }
+ EXPORT_SYMBOL(swake_up_locked);
+
++void swake_up_all_locked(struct swait_queue_head *q)
++{
++ struct swait_queue *curr;
++ int wakes = 0;
++
++ while (!list_empty(&q->task_list)) {
++
++ curr = list_first_entry(&q->task_list, typeof(*curr),
++ task_list);
++ wake_up_process(curr->task);
++ list_del_init(&curr->task_list);
++ wakes++;
++ }
++ if (pm_in_action)
++ return;
++ WARN(wakes > 2, "complete_all() with %d waiters\n", wakes);
++}
++EXPORT_SYMBOL(swake_up_all_locked);
++
+ void swake_up(struct swait_queue_head *q)
+ {
+ unsigned long flags;
+@@ -54,6 +74,7 @@
+ if (!swait_active(q))
+ return;
+
++ WARN_ON(irqs_disabled());
+ raw_spin_lock_irq(&q->lock);
+ list_splice_init(&q->task_list, &tmp);
+ while (!list_empty(&tmp)) {
+diff -Nur linux-4.8.15.orig/kernel/sched/swork.c linux-4.8.15/kernel/sched/swork.c
+--- linux-4.8.15.orig/kernel/sched/swork.c 1970-01-01 01:00:00.000000000 +0100
++++ linux-4.8.15/kernel/sched/swork.c 2017-01-01 17:07:16.039427472 +0100
+@@ -0,0 +1,173 @@
++/*
++ * Copyright (C) 2014 BMW Car IT GmbH, Daniel Wagner daniel.wagner@bmw-carit.de
++ *
++ * Provides a framework for enqueuing callbacks from irq context
++ * PREEMPT_RT_FULL safe. The callbacks are executed in kthread context.
++ */
++
++#include <linux/swait.h>
++#include <linux/swork.h>
++#include <linux/kthread.h>
++#include <linux/slab.h>
++#include <linux/spinlock.h>
++#include <linux/export.h>
++
++#define SWORK_EVENT_PENDING (1 << 0)
++
++static DEFINE_MUTEX(worker_mutex);
++static struct sworker *glob_worker;
++
++struct sworker {
++ struct list_head events;
++ struct swait_queue_head wq;
++
++ raw_spinlock_t lock;
++
++ struct task_struct *task;
++ int refs;
++};
++
++static bool swork_readable(struct sworker *worker)
++{
++ bool r;
++
++ if (kthread_should_stop())
++ return true;
++
++ raw_spin_lock_irq(&worker->lock);
++ r = !list_empty(&worker->events);
++ raw_spin_unlock_irq(&worker->lock);
++
++ return r;
++}
++
++static int swork_kthread(void *arg)
++{
++ struct sworker *worker = arg;
++
++ for (;;) {
++ swait_event_interruptible(worker->wq,
++ swork_readable(worker));
++ if (kthread_should_stop())
++ break;
++
++ raw_spin_lock_irq(&worker->lock);
++ while (!list_empty(&worker->events)) {
++ struct swork_event *sev;
++
++ sev = list_first_entry(&worker->events,
++ struct swork_event, item);
++ list_del(&sev->item);
++ raw_spin_unlock_irq(&worker->lock);
++
++ WARN_ON_ONCE(!test_and_clear_bit(SWORK_EVENT_PENDING,
++ &sev->flags));
++ sev->func(sev);
++ raw_spin_lock_irq(&worker->lock);
++ }
++ raw_spin_unlock_irq(&worker->lock);
++ }
++ return 0;
++}
++
++static struct sworker *swork_create(void)
++{
++ struct sworker *worker;
++
++ worker = kzalloc(sizeof(*worker), GFP_KERNEL);
++ if (!worker)
++ return ERR_PTR(-ENOMEM);
++
++ INIT_LIST_HEAD(&worker->events);
++ raw_spin_lock_init(&worker->lock);
++ init_swait_queue_head(&worker->wq);
++
++ worker->task = kthread_run(swork_kthread, worker, "kswork");
++ if (IS_ERR(worker->task)) {
++ kfree(worker);
++ return ERR_PTR(-ENOMEM);
++ }
++
++ return worker;
++}
++
++static void swork_destroy(struct sworker *worker)
++{
++ kthread_stop(worker->task);
++
++ WARN_ON(!list_empty(&worker->events));
++ kfree(worker);
++}
++
++/**
++ * swork_queue - queue swork
++ *
++ * Returns %false if @work was already on a queue, %true otherwise.
++ *
++ * The work is queued and processed on a random CPU
++ */
++bool swork_queue(struct swork_event *sev)
++{
++ unsigned long flags;
++
++ if (test_and_set_bit(SWORK_EVENT_PENDING, &sev->flags))
++ return false;
++
++ raw_spin_lock_irqsave(&glob_worker->lock, flags);
++ list_add_tail(&sev->item, &glob_worker->events);
++ raw_spin_unlock_irqrestore(&glob_worker->lock, flags);
++
++ swake_up(&glob_worker->wq);
++ return true;
++}
++EXPORT_SYMBOL_GPL(swork_queue);
++
++/**
++ * swork_get - get an instance of the sworker
++ *
++ * Returns an negative error code if the initialization if the worker did not
++ * work, %0 otherwise.
++ *
++ */
++int swork_get(void)
++{
++ struct sworker *worker;
++
++ mutex_lock(&worker_mutex);
++ if (!glob_worker) {
++ worker = swork_create();
++ if (IS_ERR(worker)) {
++ mutex_unlock(&worker_mutex);
++ return -ENOMEM;
++ }
++
++ glob_worker = worker;
++ }
++
++ glob_worker->refs++;
++ mutex_unlock(&worker_mutex);
++
++ return 0;
++}
++EXPORT_SYMBOL_GPL(swork_get);
++
++/**
++ * swork_put - puts an instance of the sworker
++ *
++ * Will destroy the sworker thread. This function must not be called until all
++ * queued events have been completed.
++ */
++void swork_put(void)
++{
++ mutex_lock(&worker_mutex);
++
++ glob_worker->refs--;
++ if (glob_worker->refs > 0)
++ goto out;
++
++ swork_destroy(glob_worker);
++ glob_worker = NULL;
++out:
++ mutex_unlock(&worker_mutex);
++}
++EXPORT_SYMBOL_GPL(swork_put);
+diff -Nur linux-4.8.15.orig/kernel/signal.c linux-4.8.15/kernel/signal.c
+--- linux-4.8.15.orig/kernel/signal.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/signal.c 2017-01-01 17:07:16.043427737 +0100
+@@ -14,6 +14,7 @@
+ #include <linux/export.h>
+ #include <linux/init.h>
+ #include <linux/sched.h>
++#include <linux/sched/rt.h>
+ #include <linux/fs.h>
+ #include <linux/tty.h>
+ #include <linux/binfmts.h>
+@@ -352,13 +353,30 @@
+ return false;
+ }
+
++static inline struct sigqueue *get_task_cache(struct task_struct *t)
++{
++ struct sigqueue *q = t->sigqueue_cache;
++
++ if (cmpxchg(&t->sigqueue_cache, q, NULL) != q)
++ return NULL;
++ return q;
++}
++
++static inline int put_task_cache(struct task_struct *t, struct sigqueue *q)
++{
++ if (cmpxchg(&t->sigqueue_cache, NULL, q) == NULL)
++ return 0;
++ return 1;
++}
++
+ /*
+ * allocate a new signal queue record
+ * - this may be called without locks if and only if t == current, otherwise an
+ * appropriate lock must be held to stop the target task from exiting
+ */
+ static struct sigqueue *
+-__sigqueue_alloc(int sig, struct task_struct *t, gfp_t flags, int override_rlimit)
++__sigqueue_do_alloc(int sig, struct task_struct *t, gfp_t flags,
++ int override_rlimit, int fromslab)
+ {
+ struct sigqueue *q = NULL;
+ struct user_struct *user;
+@@ -375,7 +393,10 @@
+ if (override_rlimit ||
+ atomic_read(&user->sigpending) <=
+ task_rlimit(t, RLIMIT_SIGPENDING)) {
+- q = kmem_cache_alloc(sigqueue_cachep, flags);
++ if (!fromslab)
++ q = get_task_cache(t);
++ if (!q)
++ q = kmem_cache_alloc(sigqueue_cachep, flags);
+ } else {
+ print_dropped_signal(sig);
+ }
+@@ -392,6 +413,13 @@
+ return q;
+ }
+
++static struct sigqueue *
++__sigqueue_alloc(int sig, struct task_struct *t, gfp_t flags,
++ int override_rlimit)
++{
++ return __sigqueue_do_alloc(sig, t, flags, override_rlimit, 0);
++}
++
+ static void __sigqueue_free(struct sigqueue *q)
+ {
+ if (q->flags & SIGQUEUE_PREALLOC)
+@@ -401,6 +429,21 @@
+ kmem_cache_free(sigqueue_cachep, q);
+ }
+
++static void sigqueue_free_current(struct sigqueue *q)
++{
++ struct user_struct *up;
++
++ if (q->flags & SIGQUEUE_PREALLOC)
++ return;
++
++ up = q->user;
++ if (rt_prio(current->normal_prio) && !put_task_cache(current, q)) {
++ atomic_dec(&up->sigpending);
++ free_uid(up);
++ } else
++ __sigqueue_free(q);
++}
++
+ void flush_sigqueue(struct sigpending *queue)
+ {
+ struct sigqueue *q;
+@@ -414,6 +457,21 @@
+ }
+
+ /*
++ * Called from __exit_signal. Flush tsk->pending and
++ * tsk->sigqueue_cache
++ */
++void flush_task_sigqueue(struct task_struct *tsk)
++{
++ struct sigqueue *q;
++
++ flush_sigqueue(&tsk->pending);
++
++ q = get_task_cache(tsk);
++ if (q)
++ kmem_cache_free(sigqueue_cachep, q);
++}
++
++/*
+ * Flush all pending signals for this kthread.
+ */
+ void flush_signals(struct task_struct *t)
+@@ -525,7 +583,7 @@
+ still_pending:
+ list_del_init(&first->list);
+ copy_siginfo(info, &first->info);
+- __sigqueue_free(first);
++ sigqueue_free_current(first);
+ } else {
+ /*
+ * Ok, it wasn't in the queue. This must be
+@@ -560,6 +618,8 @@
+ {
+ int signr;
+
++ WARN_ON_ONCE(tsk != current);
++
+ /* We only dequeue private signals from ourselves, we don't let
+ * signalfd steal them
+ */
+@@ -1156,8 +1216,8 @@
+ * We don't want to have recursive SIGSEGV's etc, for example,
+ * that is why we also clear SIGNAL_UNKILLABLE.
+ */
+-int
+-force_sig_info(int sig, struct siginfo *info, struct task_struct *t)
++static int
++do_force_sig_info(int sig, struct siginfo *info, struct task_struct *t)
+ {
+ unsigned long int flags;
+ int ret, blocked, ignored;
+@@ -1182,6 +1242,39 @@
+ return ret;
+ }
+
++int force_sig_info(int sig, struct siginfo *info, struct task_struct *t)
++{
++/*
++ * On some archs, PREEMPT_RT has to delay sending a signal from a trap
++ * since it can not enable preemption, and the signal code's spin_locks
++ * turn into mutexes. Instead, it must set TIF_NOTIFY_RESUME which will
++ * send the signal on exit of the trap.
++ */
++#ifdef ARCH_RT_DELAYS_SIGNAL_SEND
++ if (in_atomic()) {
++ if (WARN_ON_ONCE(t != current))
++ return 0;
++ if (WARN_ON_ONCE(t->forced_info.si_signo))
++ return 0;
++
++ if (is_si_special(info)) {
++ WARN_ON_ONCE(info != SEND_SIG_PRIV);
++ t->forced_info.si_signo = sig;
++ t->forced_info.si_errno = 0;
++ t->forced_info.si_code = SI_KERNEL;
++ t->forced_info.si_pid = 0;
++ t->forced_info.si_uid = 0;
++ } else {
++ t->forced_info = *info;
++ }
++
++ set_tsk_thread_flag(t, TIF_NOTIFY_RESUME);
++ return 0;
++ }
++#endif
++ return do_force_sig_info(sig, info, t);
++}
++
+ /*
+ * Nuke all other threads in the group.
+ */
+@@ -1216,12 +1309,12 @@
+ * Disable interrupts early to avoid deadlocks.
+ * See rcu_read_unlock() comment header for details.
+ */
+- local_irq_save(*flags);
++ local_irq_save_nort(*flags);
+ rcu_read_lock();
+ sighand = rcu_dereference(tsk->sighand);
+ if (unlikely(sighand == NULL)) {
+ rcu_read_unlock();
+- local_irq_restore(*flags);
++ local_irq_restore_nort(*flags);
+ break;
+ }
+ /*
+@@ -1242,7 +1335,7 @@
+ }
+ spin_unlock(&sighand->siglock);
+ rcu_read_unlock();
+- local_irq_restore(*flags);
++ local_irq_restore_nort(*flags);
+ }
+
+ return sighand;
+@@ -1485,7 +1578,8 @@
+ */
+ struct sigqueue *sigqueue_alloc(void)
+ {
+- struct sigqueue *q = __sigqueue_alloc(-1, current, GFP_KERNEL, 0);
++ /* Preallocated sigqueue objects always from the slabcache ! */
++ struct sigqueue *q = __sigqueue_do_alloc(-1, current, GFP_KERNEL, 0, 1);
+
+ if (q)
+ q->flags |= SIGQUEUE_PREALLOC;
+@@ -1846,15 +1940,7 @@
+ if (gstop_done && ptrace_reparented(current))
+ do_notify_parent_cldstop(current, false, why);
+
+- /*
+- * Don't want to allow preemption here, because
+- * sys_ptrace() needs this task to be inactive.
+- *
+- * XXX: implement read_unlock_no_resched().
+- */
+- preempt_disable();
+ read_unlock(&tasklist_lock);
+- preempt_enable_no_resched();
+ freezable_schedule();
+ } else {
+ /*
+diff -Nur linux-4.8.15.orig/kernel/softirq.c linux-4.8.15/kernel/softirq.c
+--- linux-4.8.15.orig/kernel/softirq.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/softirq.c 2017-01-01 17:07:16.043427737 +0100
+@@ -21,10 +21,12 @@
+ #include <linux/freezer.h>
+ #include <linux/kthread.h>
+ #include <linux/rcupdate.h>
++#include <linux/delay.h>
+ #include <linux/ftrace.h>
+ #include <linux/smp.h>
+ #include <linux/smpboot.h>
+ #include <linux/tick.h>
++#include <linux/locallock.h>
+ #include <linux/irq.h>
+
+ #define CREATE_TRACE_POINTS
+@@ -56,12 +58,108 @@
+ static struct softirq_action softirq_vec[NR_SOFTIRQS] __cacheline_aligned_in_smp;
+
+ DEFINE_PER_CPU(struct task_struct *, ksoftirqd);
++#ifdef CONFIG_PREEMPT_RT_FULL
++#define TIMER_SOFTIRQS ((1 << TIMER_SOFTIRQ) | (1 << HRTIMER_SOFTIRQ))
++DEFINE_PER_CPU(struct task_struct *, ktimer_softirqd);
++#endif
+
+ const char * const softirq_to_name[NR_SOFTIRQS] = {
+ "HI", "TIMER", "NET_TX", "NET_RX", "BLOCK", "BLOCK_IOPOLL",
+ "TASKLET", "SCHED", "HRTIMER", "RCU"
+ };
+
++#ifdef CONFIG_NO_HZ_COMMON
++# ifdef CONFIG_PREEMPT_RT_FULL
++
++struct softirq_runner {
++ struct task_struct *runner[NR_SOFTIRQS];
++};
++
++static DEFINE_PER_CPU(struct softirq_runner, softirq_runners);
++
++static inline void softirq_set_runner(unsigned int sirq)
++{
++ struct softirq_runner *sr = this_cpu_ptr(&softirq_runners);
++
++ sr->runner[sirq] = current;
++}
++
++static inline void softirq_clr_runner(unsigned int sirq)
++{
++ struct softirq_runner *sr = this_cpu_ptr(&softirq_runners);
++
++ sr->runner[sirq] = NULL;
++}
++
++/*
++ * On preempt-rt a softirq running context might be blocked on a
++ * lock. There might be no other runnable task on this CPU because the
++ * lock owner runs on some other CPU. So we have to go into idle with
++ * the pending bit set. Therefor we need to check this otherwise we
++ * warn about false positives which confuses users and defeats the
++ * whole purpose of this test.
++ *
++ * This code is called with interrupts disabled.
++ */
++void softirq_check_pending_idle(void)
++{
++ static int rate_limit;
++ struct softirq_runner *sr = this_cpu_ptr(&softirq_runners);
++ u32 warnpending;
++ int i;
++
++ if (rate_limit >= 10)
++ return;
++
++ warnpending = local_softirq_pending() & SOFTIRQ_STOP_IDLE_MASK;
++ for (i = 0; i < NR_SOFTIRQS; i++) {
++ struct task_struct *tsk = sr->runner[i];
++
++ /*
++ * The wakeup code in rtmutex.c wakes up the task
++ * _before_ it sets pi_blocked_on to NULL under
++ * tsk->pi_lock. So we need to check for both: state
++ * and pi_blocked_on.
++ */
++ if (tsk) {
++ raw_spin_lock(&tsk->pi_lock);
++ if (tsk->pi_blocked_on || tsk->state == TASK_RUNNING) {
++ /* Clear all bits pending in that task */
++ warnpending &= ~(tsk->softirqs_raised);
++ warnpending &= ~(1 << i);
++ }
++ raw_spin_unlock(&tsk->pi_lock);
++ }
++ }
++
++ if (warnpending) {
++ printk(KERN_ERR "NOHZ: local_softirq_pending %02x\n",
++ warnpending);
++ rate_limit++;
++ }
++}
++# else
++/*
++ * On !PREEMPT_RT we just printk rate limited:
++ */
++void softirq_check_pending_idle(void)
++{
++ static int rate_limit;
++
++ if (rate_limit < 10 &&
++ (local_softirq_pending() & SOFTIRQ_STOP_IDLE_MASK)) {
++ printk(KERN_ERR "NOHZ: local_softirq_pending %02x\n",
++ local_softirq_pending());
++ rate_limit++;
++ }
++}
++# endif
++
++#else /* !CONFIG_NO_HZ_COMMON */
++static inline void softirq_set_runner(unsigned int sirq) { }
++static inline void softirq_clr_runner(unsigned int sirq) { }
++#endif
++
+ /*
+ * we cannot loop indefinitely here to avoid userspace starvation,
+ * but we also don't want to introduce a worst case 1/HZ latency
+@@ -77,6 +175,79 @@
+ wake_up_process(tsk);
+ }
+
++#ifdef CONFIG_PREEMPT_RT_FULL
++static void wakeup_timer_softirqd(void)
++{
++ /* Interrupts are disabled: no need to stop preemption */
++ struct task_struct *tsk = __this_cpu_read(ktimer_softirqd);
++
++ if (tsk && tsk->state != TASK_RUNNING)
++ wake_up_process(tsk);
++}
++#endif
++
++static void handle_softirq(unsigned int vec_nr)
++{
++ struct softirq_action *h = softirq_vec + vec_nr;
++ int prev_count;
++
++ prev_count = preempt_count();
++
++ kstat_incr_softirqs_this_cpu(vec_nr);
++
++ trace_softirq_entry(vec_nr);
++ h->action(h);
++ trace_softirq_exit(vec_nr);
++ if (unlikely(prev_count != preempt_count())) {
++ pr_err("huh, entered softirq %u %s %p with preempt_count %08x, exited with %08x?\n",
++ vec_nr, softirq_to_name[vec_nr], h->action,
++ prev_count, preempt_count());
++ preempt_count_set(prev_count);
++ }
++}
++
++#ifndef CONFIG_PREEMPT_RT_FULL
++static inline int ksoftirqd_softirq_pending(void)
++{
++ return local_softirq_pending();
++}
++
++static void handle_pending_softirqs(u32 pending)
++{
++ struct softirq_action *h = softirq_vec;
++ int softirq_bit;
++
++ local_irq_enable();
++
++ h = softirq_vec;
++
++ while ((softirq_bit = ffs(pending))) {
++ unsigned int vec_nr;
++
++ h += softirq_bit - 1;
++ vec_nr = h - softirq_vec;
++ handle_softirq(vec_nr);
++
++ h++;
++ pending >>= softirq_bit;
++ }
++
++ rcu_bh_qs();
++ local_irq_disable();
++}
++
++static void run_ksoftirqd(unsigned int cpu)
++{
++ local_irq_disable();
++ if (ksoftirqd_softirq_pending()) {
++ __do_softirq();
++ local_irq_enable();
++ cond_resched_rcu_qs();
++ return;
++ }
++ local_irq_enable();
++}
++
+ /*
+ * preempt_count and SOFTIRQ_OFFSET usage:
+ * - preempt_count is changed by SOFTIRQ_OFFSET on entering or leaving
+@@ -232,10 +403,8 @@
+ unsigned long end = jiffies + MAX_SOFTIRQ_TIME;
+ unsigned long old_flags = current->flags;
+ int max_restart = MAX_SOFTIRQ_RESTART;
+- struct softirq_action *h;
+ bool in_hardirq;
+ __u32 pending;
+- int softirq_bit;
+
+ /*
+ * Mask out PF_MEMALLOC s current task context is borrowed for the
+@@ -254,36 +423,7 @@
+ /* Reset the pending bitmask before enabling irqs */
+ set_softirq_pending(0);
+
+- local_irq_enable();
+-
+- h = softirq_vec;
+-
+- while ((softirq_bit = ffs(pending))) {
+- unsigned int vec_nr;
+- int prev_count;
+-
+- h += softirq_bit - 1;
+-
+- vec_nr = h - softirq_vec;
+- prev_count = preempt_count();
+-
+- kstat_incr_softirqs_this_cpu(vec_nr);
+-
+- trace_softirq_entry(vec_nr);
+- h->action(h);
+- trace_softirq_exit(vec_nr);
+- if (unlikely(prev_count != preempt_count())) {
+- pr_err("huh, entered softirq %u %s %p with preempt_count %08x, exited with %08x?\n",
+- vec_nr, softirq_to_name[vec_nr], h->action,
+- prev_count, preempt_count());
+- preempt_count_set(prev_count);
+- }
+- h++;
+- pending >>= softirq_bit;
+- }
+-
+- rcu_bh_qs();
+- local_irq_disable();
++ handle_pending_softirqs(pending);
+
+ pending = local_softirq_pending();
+ if (pending) {
+@@ -320,6 +460,310 @@
+ }
+
+ /*
++ * This function must run with irqs disabled!
++ */
++void raise_softirq_irqoff(unsigned int nr)
++{
++ __raise_softirq_irqoff(nr);
++
++ /*
++ * If we're in an interrupt or softirq, we're done
++ * (this also catches softirq-disabled code). We will
++ * actually run the softirq once we return from
++ * the irq or softirq.
++ *
++ * Otherwise we wake up ksoftirqd to make sure we
++ * schedule the softirq soon.
++ */
++ if (!in_interrupt())
++ wakeup_softirqd();
++}
++
++void __raise_softirq_irqoff(unsigned int nr)
++{
++ trace_softirq_raise(nr);
++ or_softirq_pending(1UL << nr);
++}
++
++static inline void local_bh_disable_nort(void) { local_bh_disable(); }
++static inline void _local_bh_enable_nort(void) { _local_bh_enable(); }
++static void ksoftirqd_set_sched_params(unsigned int cpu) { }
++
++#else /* !PREEMPT_RT_FULL */
++
++/*
++ * On RT we serialize softirq execution with a cpu local lock per softirq
++ */
++static DEFINE_PER_CPU(struct local_irq_lock [NR_SOFTIRQS], local_softirq_locks);
++
++void __init softirq_early_init(void)
++{
++ int i;
++
++ for (i = 0; i < NR_SOFTIRQS; i++)
++ local_irq_lock_init(local_softirq_locks[i]);
++}
++
++static void lock_softirq(int which)
++{
++ local_lock(local_softirq_locks[which]);
++}
++
++static void unlock_softirq(int which)
++{
++ local_unlock(local_softirq_locks[which]);
++}
++
++static void do_single_softirq(int which)
++{
++ unsigned long old_flags = current->flags;
++
++ current->flags &= ~PF_MEMALLOC;
++ vtime_account_irq_enter(current);
++ current->flags |= PF_IN_SOFTIRQ;
++ lockdep_softirq_enter();
++ local_irq_enable();
++ handle_softirq(which);
++ local_irq_disable();
++ lockdep_softirq_exit();
++ current->flags &= ~PF_IN_SOFTIRQ;
++ vtime_account_irq_enter(current);
++ tsk_restore_flags(current, old_flags, PF_MEMALLOC);
++}
++
++/*
++ * Called with interrupts disabled. Process softirqs which were raised
++ * in current context (or on behalf of ksoftirqd).
++ */
++static void do_current_softirqs(void)
++{
++ while (current->softirqs_raised) {
++ int i = __ffs(current->softirqs_raised);
++ unsigned int pending, mask = (1U << i);
++
++ current->softirqs_raised &= ~mask;
++ local_irq_enable();
++
++ /*
++ * If the lock is contended, we boost the owner to
++ * process the softirq or leave the critical section
++ * now.
++ */
++ lock_softirq(i);
++ local_irq_disable();
++ softirq_set_runner(i);
++ /*
++ * Check with the local_softirq_pending() bits,
++ * whether we need to process this still or if someone
++ * else took care of it.
++ */
++ pending = local_softirq_pending();
++ if (pending & mask) {
++ set_softirq_pending(pending & ~mask);
++ do_single_softirq(i);
++ }
++ softirq_clr_runner(i);
++ WARN_ON(current->softirq_nestcnt != 1);
++ local_irq_enable();
++ unlock_softirq(i);
++ local_irq_disable();
++ }
++}
++
++void __local_bh_disable(void)
++{
++ if (++current->softirq_nestcnt == 1)
++ migrate_disable();
++}
++EXPORT_SYMBOL(__local_bh_disable);
++
++void __local_bh_enable(void)
++{
++ if (WARN_ON(current->softirq_nestcnt == 0))
++ return;
++
++ local_irq_disable();
++ if (current->softirq_nestcnt == 1 && current->softirqs_raised)
++ do_current_softirqs();
++ local_irq_enable();
++
++ if (--current->softirq_nestcnt == 0)
++ migrate_enable();
++}
++EXPORT_SYMBOL(__local_bh_enable);
++
++void _local_bh_enable(void)
++{
++ if (WARN_ON(current->softirq_nestcnt == 0))
++ return;
++ if (--current->softirq_nestcnt == 0)
++ migrate_enable();
++}
++EXPORT_SYMBOL(_local_bh_enable);
++
++int in_serving_softirq(void)
++{
++ return current->flags & PF_IN_SOFTIRQ;
++}
++EXPORT_SYMBOL(in_serving_softirq);
++
++/* Called with preemption disabled */
++static void run_ksoftirqd(unsigned int cpu)
++{
++ local_irq_disable();
++ current->softirq_nestcnt++;
++
++ do_current_softirqs();
++ current->softirq_nestcnt--;
++ local_irq_enable();
++ cond_resched_rcu_qs();
++}
++
++/*
++ * Called from netif_rx_ni(). Preemption enabled, but migration
++ * disabled. So the cpu can't go away under us.
++ */
++void thread_do_softirq(void)
++{
++ if (!in_serving_softirq() && current->softirqs_raised) {
++ current->softirq_nestcnt++;
++ do_current_softirqs();
++ current->softirq_nestcnt--;
++ }
++}
++
++static void do_raise_softirq_irqoff(unsigned int nr)
++{
++ unsigned int mask;
++
++ mask = 1UL << nr;
++
++ trace_softirq_raise(nr);
++ or_softirq_pending(mask);
++
++ /*
++ * If we are not in a hard interrupt and inside a bh disabled
++ * region, we simply raise the flag on current. local_bh_enable()
++ * will make sure that the softirq is executed. Otherwise we
++ * delegate it to ksoftirqd.
++ */
++ if (!in_irq() && current->softirq_nestcnt)
++ current->softirqs_raised |= mask;
++ else if (!__this_cpu_read(ksoftirqd) || !__this_cpu_read(ktimer_softirqd))
++ return;
++
++ if (mask & TIMER_SOFTIRQS)
++ __this_cpu_read(ktimer_softirqd)->softirqs_raised |= mask;
++ else
++ __this_cpu_read(ksoftirqd)->softirqs_raised |= mask;
++}
++
++static void wakeup_proper_softirq(unsigned int nr)
++{
++ if ((1UL << nr) & TIMER_SOFTIRQS)
++ wakeup_timer_softirqd();
++ else
++ wakeup_softirqd();
++}
++
++
++void __raise_softirq_irqoff(unsigned int nr)
++{
++ do_raise_softirq_irqoff(nr);
++ if (!in_irq() && !current->softirq_nestcnt)
++ wakeup_proper_softirq(nr);
++}
++
++/*
++ * Same as __raise_softirq_irqoff() but will process them in ksoftirqd
++ */
++void __raise_softirq_irqoff_ksoft(unsigned int nr)
++{
++ unsigned int mask;
++
++ if (WARN_ON_ONCE(!__this_cpu_read(ksoftirqd) ||
++ !__this_cpu_read(ktimer_softirqd)))
++ return;
++ mask = 1UL << nr;
++
++ trace_softirq_raise(nr);
++ or_softirq_pending(mask);
++ if (mask & TIMER_SOFTIRQS)
++ __this_cpu_read(ktimer_softirqd)->softirqs_raised |= mask;
++ else
++ __this_cpu_read(ksoftirqd)->softirqs_raised |= mask;
++ wakeup_proper_softirq(nr);
++}
++
++/*
++ * This function must run with irqs disabled!
++ */
++void raise_softirq_irqoff(unsigned int nr)
++{
++ do_raise_softirq_irqoff(nr);
++
++ /*
++ * If we're in an hard interrupt we let irq return code deal
++ * with the wakeup of ksoftirqd.
++ */
++ if (in_irq())
++ return;
++ /*
++ * If we are in thread context but outside of a bh disabled
++ * region, we need to wake ksoftirqd as well.
++ *
++ * CHECKME: Some of the places which do that could be wrapped
++ * into local_bh_disable/enable pairs. Though it's unclear
++ * whether this is worth the effort. To find those places just
++ * raise a WARN() if the condition is met.
++ */
++ if (!current->softirq_nestcnt)
++ wakeup_proper_softirq(nr);
++}
++
++static inline int ksoftirqd_softirq_pending(void)
++{
++ return current->softirqs_raised;
++}
++
++static inline void local_bh_disable_nort(void) { }
++static inline void _local_bh_enable_nort(void) { }
++
++static inline void ksoftirqd_set_sched_params(unsigned int cpu)
++{
++ /* Take over all but timer pending softirqs when starting */
++ local_irq_disable();
++ current->softirqs_raised = local_softirq_pending() & ~TIMER_SOFTIRQS;
++ local_irq_enable();
++}
++
++static inline void ktimer_softirqd_set_sched_params(unsigned int cpu)
++{
++ struct sched_param param = { .sched_priority = 1 };
++
++ sched_setscheduler(current, SCHED_FIFO, &param);
++
++ /* Take over timer pending softirqs when starting */
++ local_irq_disable();
++ current->softirqs_raised = local_softirq_pending() & TIMER_SOFTIRQS;
++ local_irq_enable();
++}
++
++static inline void ktimer_softirqd_clr_sched_params(unsigned int cpu,
++ bool online)
++{
++ struct sched_param param = { .sched_priority = 0 };
++
++ sched_setscheduler(current, SCHED_NORMAL, &param);
++}
++
++static int ktimer_softirqd_should_run(unsigned int cpu)
++{
++ return current->softirqs_raised;
++}
++
++#endif /* PREEMPT_RT_FULL */
++/*
+ * Enter an interrupt context.
+ */
+ void irq_enter(void)
+@@ -330,9 +774,9 @@
+ * Prevent raise_softirq from needlessly waking up ksoftirqd
+ * here, as softirq will be serviced on return from interrupt.
+ */
+- local_bh_disable();
++ local_bh_disable_nort();
+ tick_irq_enter();
+- _local_bh_enable();
++ _local_bh_enable_nort();
+ }
+
+ __irq_enter();
+@@ -340,6 +784,7 @@
+
+ static inline void invoke_softirq(void)
+ {
++#ifndef CONFIG_PREEMPT_RT_FULL
+ if (!force_irqthreads) {
+ #ifdef CONFIG_HAVE_IRQ_EXIT_ON_IRQ_STACK
+ /*
+@@ -359,6 +804,18 @@
+ } else {
+ wakeup_softirqd();
+ }
++#else /* PREEMPT_RT_FULL */
++ unsigned long flags;
++
++ local_irq_save(flags);
++ if (__this_cpu_read(ksoftirqd) &&
++ __this_cpu_read(ksoftirqd)->softirqs_raised)
++ wakeup_softirqd();
++ if (__this_cpu_read(ktimer_softirqd) &&
++ __this_cpu_read(ktimer_softirqd)->softirqs_raised)
++ wakeup_timer_softirqd();
++ local_irq_restore(flags);
++#endif
+ }
+
+ static inline void tick_irq_exit(void)
+@@ -395,26 +852,6 @@
+ trace_hardirq_exit(); /* must be last! */
+ }
+
+-/*
+- * This function must run with irqs disabled!
+- */
+-inline void raise_softirq_irqoff(unsigned int nr)
+-{
+- __raise_softirq_irqoff(nr);
+-
+- /*
+- * If we're in an interrupt or softirq, we're done
+- * (this also catches softirq-disabled code). We will
+- * actually run the softirq once we return from
+- * the irq or softirq.
+- *
+- * Otherwise we wake up ksoftirqd to make sure we
+- * schedule the softirq soon.
+- */
+- if (!in_interrupt())
+- wakeup_softirqd();
+-}
+-
+ void raise_softirq(unsigned int nr)
+ {
+ unsigned long flags;
+@@ -424,12 +861,6 @@
+ local_irq_restore(flags);
+ }
+
+-void __raise_softirq_irqoff(unsigned int nr)
+-{
+- trace_softirq_raise(nr);
+- or_softirq_pending(1UL << nr);
+-}
+-
+ void open_softirq(int nr, void (*action)(struct softirq_action *))
+ {
+ softirq_vec[nr].action = action;
+@@ -446,15 +877,45 @@
+ static DEFINE_PER_CPU(struct tasklet_head, tasklet_vec);
+ static DEFINE_PER_CPU(struct tasklet_head, tasklet_hi_vec);
+
++static void inline
++__tasklet_common_schedule(struct tasklet_struct *t, struct tasklet_head *head, unsigned int nr)
++{
++ if (tasklet_trylock(t)) {
++again:
++ /* We may have been preempted before tasklet_trylock
++ * and __tasklet_action may have already run.
++ * So double check the sched bit while the takslet
++ * is locked before adding it to the list.
++ */
++ if (test_bit(TASKLET_STATE_SCHED, &t->state)) {
++ t->next = NULL;
++ *head->tail = t;
++ head->tail = &(t->next);
++ raise_softirq_irqoff(nr);
++ tasklet_unlock(t);
++ } else {
++ /* This is subtle. If we hit the corner case above
++ * It is possible that we get preempted right here,
++ * and another task has successfully called
++ * tasklet_schedule(), then this function, and
++ * failed on the trylock. Thus we must be sure
++ * before releasing the tasklet lock, that the
++ * SCHED_BIT is clear. Otherwise the tasklet
++ * may get its SCHED_BIT set, but not added to the
++ * list
++ */
++ if (!tasklet_tryunlock(t))
++ goto again;
++ }
++ }
++}
++
+ void __tasklet_schedule(struct tasklet_struct *t)
+ {
+ unsigned long flags;
+
+ local_irq_save(flags);
+- t->next = NULL;
+- *__this_cpu_read(tasklet_vec.tail) = t;
+- __this_cpu_write(tasklet_vec.tail, &(t->next));
+- raise_softirq_irqoff(TASKLET_SOFTIRQ);
++ __tasklet_common_schedule(t, this_cpu_ptr(&tasklet_vec), TASKLET_SOFTIRQ);
+ local_irq_restore(flags);
+ }
+ EXPORT_SYMBOL(__tasklet_schedule);
+@@ -464,10 +925,7 @@
+ unsigned long flags;
+
+ local_irq_save(flags);
+- t->next = NULL;
+- *__this_cpu_read(tasklet_hi_vec.tail) = t;
+- __this_cpu_write(tasklet_hi_vec.tail, &(t->next));
+- raise_softirq_irqoff(HI_SOFTIRQ);
++ __tasklet_common_schedule(t, this_cpu_ptr(&tasklet_hi_vec), HI_SOFTIRQ);
+ local_irq_restore(flags);
+ }
+ EXPORT_SYMBOL(__tasklet_hi_schedule);
+@@ -476,82 +934,122 @@
+ {
+ BUG_ON(!irqs_disabled());
+
+- t->next = __this_cpu_read(tasklet_hi_vec.head);
+- __this_cpu_write(tasklet_hi_vec.head, t);
+- __raise_softirq_irqoff(HI_SOFTIRQ);
++ __tasklet_hi_schedule(t);
+ }
+ EXPORT_SYMBOL(__tasklet_hi_schedule_first);
+
+-static void tasklet_action(struct softirq_action *a)
++void tasklet_enable(struct tasklet_struct *t)
+ {
+- struct tasklet_struct *list;
++ if (!atomic_dec_and_test(&t->count))
++ return;
++ if (test_and_clear_bit(TASKLET_STATE_PENDING, &t->state))
++ tasklet_schedule(t);
++}
++EXPORT_SYMBOL(tasklet_enable);
+
+- local_irq_disable();
+- list = __this_cpu_read(tasklet_vec.head);
+- __this_cpu_write(tasklet_vec.head, NULL);
+- __this_cpu_write(tasklet_vec.tail, this_cpu_ptr(&tasklet_vec.head));
+- local_irq_enable();
++static void __tasklet_action(struct softirq_action *a,
++ struct tasklet_struct *list)
++{
++ int loops = 1000000;
+
+ while (list) {
+ struct tasklet_struct *t = list;
+
+ list = list->next;
+
+- if (tasklet_trylock(t)) {
+- if (!atomic_read(&t->count)) {
+- if (!test_and_clear_bit(TASKLET_STATE_SCHED,
+- &t->state))
+- BUG();
+- t->func(t->data);
+- tasklet_unlock(t);
+- continue;
+- }
+- tasklet_unlock(t);
++ /*
++ * Should always succeed - after a tasklist got on the
++ * list (after getting the SCHED bit set from 0 to 1),
++ * nothing but the tasklet softirq it got queued to can
++ * lock it:
++ */
++ if (!tasklet_trylock(t)) {
++ WARN_ON(1);
++ continue;
+ }
+
+- local_irq_disable();
+ t->next = NULL;
+- *__this_cpu_read(tasklet_vec.tail) = t;
+- __this_cpu_write(tasklet_vec.tail, &(t->next));
+- __raise_softirq_irqoff(TASKLET_SOFTIRQ);
+- local_irq_enable();
++
++ /*
++ * If we cannot handle the tasklet because it's disabled,
++ * mark it as pending. tasklet_enable() will later
++ * re-schedule the tasklet.
++ */
++ if (unlikely(atomic_read(&t->count))) {
++out_disabled:
++ /* implicit unlock: */
++ wmb();
++ t->state = TASKLET_STATEF_PENDING;
++ continue;
++ }
++
++ /*
++ * After this point on the tasklet might be rescheduled
++ * on another CPU, but it can only be added to another
++ * CPU's tasklet list if we unlock the tasklet (which we
++ * dont do yet).
++ */
++ if (!test_and_clear_bit(TASKLET_STATE_SCHED, &t->state))
++ WARN_ON(1);
++
++again:
++ t->func(t->data);
++
++ /*
++ * Try to unlock the tasklet. We must use cmpxchg, because
++ * another CPU might have scheduled or disabled the tasklet.
++ * We only allow the STATE_RUN -> 0 transition here.
++ */
++ while (!tasklet_tryunlock(t)) {
++ /*
++ * If it got disabled meanwhile, bail out:
++ */
++ if (atomic_read(&t->count))
++ goto out_disabled;
++ /*
++ * If it got scheduled meanwhile, re-execute
++ * the tasklet function:
++ */
++ if (test_and_clear_bit(TASKLET_STATE_SCHED, &t->state))
++ goto again;
++ if (!--loops) {
++ printk("hm, tasklet state: %08lx\n", t->state);
++ WARN_ON(1);
++ tasklet_unlock(t);
++ break;
++ }
++ }
+ }
+ }
+
++static void tasklet_action(struct softirq_action *a)
++{
++ struct tasklet_struct *list;
++
++ local_irq_disable();
++
++ list = __this_cpu_read(tasklet_vec.head);
++ __this_cpu_write(tasklet_vec.head, NULL);
++ __this_cpu_write(tasklet_vec.tail, this_cpu_ptr(&tasklet_vec.head));
++
++ local_irq_enable();
++
++ __tasklet_action(a, list);
++}
++
+ static void tasklet_hi_action(struct softirq_action *a)
+ {
+ struct tasklet_struct *list;
+
+ local_irq_disable();
++
+ list = __this_cpu_read(tasklet_hi_vec.head);
+ __this_cpu_write(tasklet_hi_vec.head, NULL);
+ __this_cpu_write(tasklet_hi_vec.tail, this_cpu_ptr(&tasklet_hi_vec.head));
+- local_irq_enable();
+
+- while (list) {
+- struct tasklet_struct *t = list;
+-
+- list = list->next;
+-
+- if (tasklet_trylock(t)) {
+- if (!atomic_read(&t->count)) {
+- if (!test_and_clear_bit(TASKLET_STATE_SCHED,
+- &t->state))
+- BUG();
+- t->func(t->data);
+- tasklet_unlock(t);
+- continue;
+- }
+- tasklet_unlock(t);
+- }
++ local_irq_enable();
+
+- local_irq_disable();
+- t->next = NULL;
+- *__this_cpu_read(tasklet_hi_vec.tail) = t;
+- __this_cpu_write(tasklet_hi_vec.tail, &(t->next));
+- __raise_softirq_irqoff(HI_SOFTIRQ);
+- local_irq_enable();
+- }
++ __tasklet_action(a, list);
+ }
+
+ void tasklet_init(struct tasklet_struct *t,
+@@ -572,7 +1070,7 @@
+
+ while (test_and_set_bit(TASKLET_STATE_SCHED, &t->state)) {
+ do {
+- yield();
++ msleep(1);
+ } while (test_bit(TASKLET_STATE_SCHED, &t->state));
+ }
+ tasklet_unlock_wait(t);
+@@ -646,25 +1144,26 @@
+ open_softirq(HI_SOFTIRQ, tasklet_hi_action);
+ }
+
+-static int ksoftirqd_should_run(unsigned int cpu)
+-{
+- return local_softirq_pending();
+-}
+-
+-static void run_ksoftirqd(unsigned int cpu)
++#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT_FULL)
++void tasklet_unlock_wait(struct tasklet_struct *t)
+ {
+- local_irq_disable();
+- if (local_softirq_pending()) {
++ while (test_bit(TASKLET_STATE_RUN, &(t)->state)) {
+ /*
+- * We can safely run softirq on inline stack, as we are not deep
+- * in the task stack here.
++ * Hack for now to avoid this busy-loop:
+ */
+- __do_softirq();
+- local_irq_enable();
+- cond_resched_rcu_qs();
+- return;
++#ifdef CONFIG_PREEMPT_RT_FULL
++ msleep(1);
++#else
++ barrier();
++#endif
+ }
+- local_irq_enable();
++}
++EXPORT_SYMBOL(tasklet_unlock_wait);
++#endif
++
++static int ksoftirqd_should_run(unsigned int cpu)
++{
++ return ksoftirqd_softirq_pending();
+ }
+
+ #ifdef CONFIG_HOTPLUG_CPU
+@@ -746,16 +1245,31 @@
+
+ static struct smp_hotplug_thread softirq_threads = {
+ .store = &ksoftirqd,
++ .setup = ksoftirqd_set_sched_params,
+ .thread_should_run = ksoftirqd_should_run,
+ .thread_fn = run_ksoftirqd,
+ .thread_comm = "ksoftirqd/%u",
+ };
+
++#ifdef CONFIG_PREEMPT_RT_FULL
++static struct smp_hotplug_thread softirq_timer_threads = {
++ .store = &ktimer_softirqd,
++ .setup = ktimer_softirqd_set_sched_params,
++ .cleanup = ktimer_softirqd_clr_sched_params,
++ .thread_should_run = ktimer_softirqd_should_run,
++ .thread_fn = run_ksoftirqd,
++ .thread_comm = "ktimersoftd/%u",
++};
++#endif
++
+ static __init int spawn_ksoftirqd(void)
+ {
+ register_cpu_notifier(&cpu_nfb);
+
+ BUG_ON(smpboot_register_percpu_thread(&softirq_threads));
++#ifdef CONFIG_PREEMPT_RT_FULL
++ BUG_ON(smpboot_register_percpu_thread(&softirq_timer_threads));
++#endif
+
+ return 0;
+ }
+diff -Nur linux-4.8.15.orig/kernel/stop_machine.c linux-4.8.15/kernel/stop_machine.c
+--- linux-4.8.15.orig/kernel/stop_machine.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/stop_machine.c 2017-01-01 17:07:16.043427737 +0100
+@@ -37,7 +37,7 @@
+ struct cpu_stopper {
+ struct task_struct *thread;
+
+- spinlock_t lock;
++ raw_spinlock_t lock;
+ bool enabled; /* is this stopper enabled? */
+ struct list_head works; /* list of pending works */
+
+@@ -83,14 +83,14 @@
+ unsigned long flags;
+ bool enabled;
+
+- spin_lock_irqsave(&stopper->lock, flags);
++ raw_spin_lock_irqsave(&stopper->lock, flags);
+ enabled = stopper->enabled;
+ if (enabled)
+ __cpu_stop_queue_work(stopper, work);
+ else if (work->done)
+ cpu_stop_signal_done(work->done);
+- spin_unlock_irqrestore(&stopper->lock, flags);
+
++ raw_spin_unlock_irqrestore(&stopper->lock, flags);
+ return enabled;
+ }
+
+@@ -232,8 +232,8 @@
+ int err;
+
+ lg_double_lock(&stop_cpus_lock, cpu1, cpu2);
+- spin_lock_irq(&stopper1->lock);
+- spin_lock_nested(&stopper2->lock, SINGLE_DEPTH_NESTING);
++ raw_spin_lock_irq(&stopper1->lock);
++ raw_spin_lock_nested(&stopper2->lock, SINGLE_DEPTH_NESTING);
+
+ err = -ENOENT;
+ if (!stopper1->enabled || !stopper2->enabled)
+@@ -243,8 +243,8 @@
+ __cpu_stop_queue_work(stopper1, work1);
+ __cpu_stop_queue_work(stopper2, work2);
+ unlock:
+- spin_unlock(&stopper2->lock);
+- spin_unlock_irq(&stopper1->lock);
++ raw_spin_unlock(&stopper2->lock);
++ raw_spin_unlock_irq(&stopper1->lock);
+ lg_double_unlock(&stop_cpus_lock, cpu1, cpu2);
+
+ return err;
+@@ -321,18 +321,21 @@
+
+ static bool queue_stop_cpus_work(const struct cpumask *cpumask,
+ cpu_stop_fn_t fn, void *arg,
+- struct cpu_stop_done *done)
++ struct cpu_stop_done *done, bool inactive)
+ {
+ struct cpu_stop_work *work;
+ unsigned int cpu;
+ bool queued = false;
+
+ /*
+- * Disable preemption while queueing to avoid getting
+- * preempted by a stopper which might wait for other stoppers
+- * to enter @fn which can lead to deadlock.
++ * Make sure that all work is queued on all cpus before
++ * any of the cpus can execute it.
+ */
+- lg_global_lock(&stop_cpus_lock);
++ if (!inactive)
++ lg_global_lock(&stop_cpus_lock);
++ else
++ lg_global_trylock_relax(&stop_cpus_lock);
++
+ for_each_cpu(cpu, cpumask) {
+ work = &per_cpu(cpu_stopper.stop_work, cpu);
+ work->fn = fn;
+@@ -352,7 +355,7 @@
+ struct cpu_stop_done done;
+
+ cpu_stop_init_done(&done, cpumask_weight(cpumask));
+- if (!queue_stop_cpus_work(cpumask, fn, arg, &done))
++ if (!queue_stop_cpus_work(cpumask, fn, arg, &done, false))
+ return -ENOENT;
+ wait_for_completion(&done.completion);
+ return done.ret;
+@@ -433,9 +436,9 @@
+ unsigned long flags;
+ int run;
+
+- spin_lock_irqsave(&stopper->lock, flags);
++ raw_spin_lock_irqsave(&stopper->lock, flags);
+ run = !list_empty(&stopper->works);
+- spin_unlock_irqrestore(&stopper->lock, flags);
++ raw_spin_unlock_irqrestore(&stopper->lock, flags);
+ return run;
+ }
+
+@@ -446,13 +449,13 @@
+
+ repeat:
+ work = NULL;
+- spin_lock_irq(&stopper->lock);
++ raw_spin_lock_irq(&stopper->lock);
+ if (!list_empty(&stopper->works)) {
+ work = list_first_entry(&stopper->works,
+ struct cpu_stop_work, list);
+ list_del_init(&work->list);
+ }
+- spin_unlock_irq(&stopper->lock);
++ raw_spin_unlock_irq(&stopper->lock);
+
+ if (work) {
+ cpu_stop_fn_t fn = work->fn;
+@@ -460,6 +463,16 @@
+ struct cpu_stop_done *done = work->done;
+ int ret;
+
++ /*
++ * Wait until the stopper finished scheduling on all
++ * cpus
++ */
++ lg_global_lock(&stop_cpus_lock);
++ /*
++ * Let other cpu threads continue as well
++ */
++ lg_global_unlock(&stop_cpus_lock);
++
+ /* cpu stop callbacks must not sleep, make in_atomic() == T */
+ preempt_count_inc();
+ ret = fn(arg);
+@@ -526,10 +539,12 @@
+ for_each_possible_cpu(cpu) {
+ struct cpu_stopper *stopper = &per_cpu(cpu_stopper, cpu);
+
+- spin_lock_init(&stopper->lock);
++ raw_spin_lock_init(&stopper->lock);
+ INIT_LIST_HEAD(&stopper->works);
+ }
+
++ lg_lock_init(&stop_cpus_lock, "stop_cpus_lock");
++
+ BUG_ON(smpboot_register_percpu_thread(&cpu_stop_threads));
+ stop_machine_unpark(raw_smp_processor_id());
+ stop_machine_initialized = true;
+@@ -624,7 +639,7 @@
+ set_state(&msdata, MULTI_STOP_PREPARE);
+ cpu_stop_init_done(&done, num_active_cpus());
+ queue_stop_cpus_work(cpu_active_mask, multi_cpu_stop, &msdata,
+- &done);
++ &done, true);
+ ret = multi_cpu_stop(&msdata);
+
+ /* Busy wait for completion. */
+diff -Nur linux-4.8.15.orig/kernel/time/hrtimer.c linux-4.8.15/kernel/time/hrtimer.c
+--- linux-4.8.15.orig/kernel/time/hrtimer.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/time/hrtimer.c 2017-01-01 17:07:16.047427991 +0100
+@@ -53,6 +53,7 @@
+ #include <asm/uaccess.h>
+
+ #include <trace/events/timer.h>
++#include <trace/events/hist.h>
+
+ #include "tick-internal.h"
+
+@@ -695,6 +696,29 @@
+ retrigger_next_event(NULL);
+ }
+
++#ifdef CONFIG_PREEMPT_RT_FULL
++
++static struct swork_event clock_set_delay_work;
++
++static void run_clock_set_delay(struct swork_event *event)
++{
++ clock_was_set();
++}
++
++void clock_was_set_delayed(void)
++{
++ swork_queue(&clock_set_delay_work);
++}
++
++static __init int create_clock_set_delay_thread(void)
++{
++ WARN_ON(swork_get());
++ INIT_SWORK(&clock_set_delay_work, run_clock_set_delay);
++ return 0;
++}
++early_initcall(create_clock_set_delay_thread);
++#else /* PREEMPT_RT_FULL */
++
+ static void clock_was_set_work(struct work_struct *work)
+ {
+ clock_was_set();
+@@ -710,6 +734,7 @@
+ {
+ schedule_work(&hrtimer_work);
+ }
++#endif
+
+ #else
+
+@@ -719,11 +744,8 @@
+ static inline void hrtimer_switch_to_hres(void) { }
+ static inline void
+ hrtimer_force_reprogram(struct hrtimer_cpu_base *base, int skip_equal) { }
+-static inline int hrtimer_reprogram(struct hrtimer *timer,
+- struct hrtimer_clock_base *base)
+-{
+- return 0;
+-}
++static inline void hrtimer_reprogram(struct hrtimer *timer,
++ struct hrtimer_clock_base *base) { }
+ static inline void hrtimer_init_hres(struct hrtimer_cpu_base *base) { }
+ static inline void retrigger_next_event(void *arg) { }
+
+@@ -855,6 +877,32 @@
+ }
+ EXPORT_SYMBOL_GPL(hrtimer_forward);
+
++#ifdef CONFIG_PREEMPT_RT_BASE
++# define wake_up_timer_waiters(b) wake_up(&(b)->wait)
++
++/**
++ * hrtimer_wait_for_timer - Wait for a running timer
++ *
++ * @timer: timer to wait for
++ *
++ * The function waits in case the timers callback function is
++ * currently executed on the waitqueue of the timer base. The
++ * waitqueue is woken up after the timer callback function has
++ * finished execution.
++ */
++void hrtimer_wait_for_timer(const struct hrtimer *timer)
++{
++ struct hrtimer_clock_base *base = timer->base;
++
++ if (base && base->cpu_base && !timer->irqsafe)
++ wait_event(base->cpu_base->wait,
++ !(hrtimer_callback_running(timer)));
++}
++
++#else
++# define wake_up_timer_waiters(b) do { } while (0)
++#endif
++
+ /*
+ * enqueue_hrtimer - internal function to (re)start a timer
+ *
+@@ -896,6 +944,11 @@
+ if (!(state & HRTIMER_STATE_ENQUEUED))
+ return;
+
++ if (unlikely(!list_empty(&timer->cb_entry))) {
++ list_del_init(&timer->cb_entry);
++ return;
++ }
++
+ if (!timerqueue_del(&base->active, &timer->node))
+ cpu_base->active_bases &= ~(1 << base->index);
+
+@@ -991,7 +1044,16 @@
+ new_base = switch_hrtimer_base(timer, base, mode & HRTIMER_MODE_PINNED);
+
+ timer_stats_hrtimer_set_start_info(timer);
++#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST
++ {
++ ktime_t now = new_base->get_time();
+
++ if (ktime_to_ns(tim) < ktime_to_ns(now))
++ timer->praecox = now;
++ else
++ timer->praecox = ktime_set(0, 0);
++ }
++#endif
+ leftmost = enqueue_hrtimer(timer, new_base);
+ if (!leftmost)
+ goto unlock;
+@@ -1063,7 +1125,7 @@
+
+ if (ret >= 0)
+ return ret;
+- cpu_relax();
++ hrtimer_wait_for_timer(timer);
+ }
+ }
+ EXPORT_SYMBOL_GPL(hrtimer_cancel);
+@@ -1127,6 +1189,7 @@
+
+ base = hrtimer_clockid_to_base(clock_id);
+ timer->base = &cpu_base->clock_base[base];
++ INIT_LIST_HEAD(&timer->cb_entry);
+ timerqueue_init(&timer->node);
+
+ #ifdef CONFIG_TIMER_STATS
+@@ -1167,6 +1230,7 @@
+ seq = raw_read_seqcount_begin(&cpu_base->seq);
+
+ if (timer->state != HRTIMER_STATE_INACTIVE ||
++ cpu_base->running_soft == timer ||
+ cpu_base->running == timer)
+ return true;
+
+@@ -1265,10 +1329,112 @@
+ cpu_base->running = NULL;
+ }
+
++#ifdef CONFIG_PREEMPT_RT_BASE
++static void hrtimer_rt_reprogram(int restart, struct hrtimer *timer,
++ struct hrtimer_clock_base *base)
++{
++ int leftmost;
++
++ if (restart != HRTIMER_NORESTART &&
++ !(timer->state & HRTIMER_STATE_ENQUEUED)) {
++
++ leftmost = enqueue_hrtimer(timer, base);
++ if (!leftmost)
++ return;
++#ifdef CONFIG_HIGH_RES_TIMERS
++ if (!hrtimer_is_hres_active(timer)) {
++ /*
++ * Kick to reschedule the next tick to handle the new timer
++ * on dynticks target.
++ */
++ if (base->cpu_base->nohz_active)
++ wake_up_nohz_cpu(base->cpu_base->cpu);
++ } else {
++
++ hrtimer_reprogram(timer, base);
++ }
++#endif
++ }
++}
++
++/*
++ * The changes in mainline which removed the callback modes from
++ * hrtimer are not yet working with -rt. The non wakeup_process()
++ * based callbacks which involve sleeping locks need to be treated
++ * seperately.
++ */
++static void hrtimer_rt_run_pending(void)
++{
++ enum hrtimer_restart (*fn)(struct hrtimer *);
++ struct hrtimer_cpu_base *cpu_base;
++ struct hrtimer_clock_base *base;
++ struct hrtimer *timer;
++ int index, restart;
++
++ local_irq_disable();
++ cpu_base = &per_cpu(hrtimer_bases, smp_processor_id());
++
++ raw_spin_lock(&cpu_base->lock);
++
++ for (index = 0; index < HRTIMER_MAX_CLOCK_BASES; index++) {
++ base = &cpu_base->clock_base[index];
++
++ while (!list_empty(&base->expired)) {
++ timer = list_first_entry(&base->expired,
++ struct hrtimer, cb_entry);
++
++ /*
++ * Same as the above __run_hrtimer function
++ * just we run with interrupts enabled.
++ */
++ debug_deactivate(timer);
++ cpu_base->running_soft = timer;
++ raw_write_seqcount_barrier(&cpu_base->seq);
++
++ __remove_hrtimer(timer, base, HRTIMER_STATE_INACTIVE, 0);
++ timer_stats_account_hrtimer(timer);
++ fn = timer->function;
++
++ raw_spin_unlock_irq(&cpu_base->lock);
++ restart = fn(timer);
++ raw_spin_lock_irq(&cpu_base->lock);
++
++ hrtimer_rt_reprogram(restart, timer, base);
++ raw_write_seqcount_barrier(&cpu_base->seq);
++
++ WARN_ON_ONCE(cpu_base->running_soft != timer);
++ cpu_base->running_soft = NULL;
++ }
++ }
++
++ raw_spin_unlock_irq(&cpu_base->lock);
++
++ wake_up_timer_waiters(cpu_base);
++}
++
++static int hrtimer_rt_defer(struct hrtimer *timer)
++{
++ if (timer->irqsafe)
++ return 0;
++
++ __remove_hrtimer(timer, timer->base, timer->state, 0);
++ list_add_tail(&timer->cb_entry, &timer->base->expired);
++ return 1;
++}
++
++#else
++
++static inline int hrtimer_rt_defer(struct hrtimer *timer) { return 0; }
++
++#endif
++
++static enum hrtimer_restart hrtimer_wakeup(struct hrtimer *timer);
++
+ static void __hrtimer_run_queues(struct hrtimer_cpu_base *cpu_base, ktime_t now)
+ {
+ struct hrtimer_clock_base *base = cpu_base->clock_base;
+ unsigned int active = cpu_base->active_bases;
++ int raise = 0;
+
+ for (; active; base++, active >>= 1) {
+ struct timerqueue_node *node;
+@@ -1284,6 +1450,15 @@
+
+ timer = container_of(node, struct hrtimer, node);
+
++ trace_hrtimer_interrupt(raw_smp_processor_id(),
++ ktime_to_ns(ktime_sub(ktime_to_ns(timer->praecox) ?
++ timer->praecox : hrtimer_get_expires(timer),
++ basenow)),
++ current,
++ timer->function == hrtimer_wakeup ?
++ container_of(timer, struct hrtimer_sleeper,
++ timer)->task : NULL);
++
+ /*
+ * The immediate goal for using the softexpires is
+ * minimizing wakeups, not running timers at the
+@@ -1299,9 +1474,14 @@
+ if (basenow.tv64 < hrtimer_get_softexpires_tv64(timer))
+ break;
+
+- __run_hrtimer(cpu_base, base, timer, &basenow);
++ if (!hrtimer_rt_defer(timer))
++ __run_hrtimer(cpu_base, base, timer, &basenow);
++ else
++ raise = 1;
+ }
+ }
++ if (raise)
++ raise_softirq_irqoff(HRTIMER_SOFTIRQ);
+ }
+
+ #ifdef CONFIG_HIGH_RES_TIMERS
+@@ -1464,16 +1644,18 @@
+ void hrtimer_init_sleeper(struct hrtimer_sleeper *sl, struct task_struct *task)
+ {
+ sl->timer.function = hrtimer_wakeup;
++ sl->timer.irqsafe = 1;
+ sl->task = task;
+ }
+ EXPORT_SYMBOL_GPL(hrtimer_init_sleeper);
+
+-static int __sched do_nanosleep(struct hrtimer_sleeper *t, enum hrtimer_mode mode)
++static int __sched do_nanosleep(struct hrtimer_sleeper *t, enum hrtimer_mode mode,
++ unsigned long state)
+ {
+ hrtimer_init_sleeper(t, current);
+
+ do {
+- set_current_state(TASK_INTERRUPTIBLE);
++ set_current_state(state);
+ hrtimer_start_expires(&t->timer, mode);
+
+ if (likely(t->task))
+@@ -1515,7 +1697,8 @@
+ HRTIMER_MODE_ABS);
+ hrtimer_set_expires_tv64(&t.timer, restart->nanosleep.expires);
+
+- if (do_nanosleep(&t, HRTIMER_MODE_ABS))
++ /* cpu_chill() does not care about restart state. */
++ if (do_nanosleep(&t, HRTIMER_MODE_ABS, TASK_INTERRUPTIBLE))
+ goto out;
+
+ rmtp = restart->nanosleep.rmtp;
+@@ -1532,8 +1715,10 @@
+ return ret;
+ }
+
+-long hrtimer_nanosleep(struct timespec *rqtp, struct timespec __user *rmtp,
+- const enum hrtimer_mode mode, const clockid_t clockid)
++static long
++__hrtimer_nanosleep(struct timespec *rqtp, struct timespec __user *rmtp,
++ const enum hrtimer_mode mode, const clockid_t clockid,
++ unsigned long state)
+ {
+ struct restart_block *restart;
+ struct hrtimer_sleeper t;
+@@ -1546,7 +1731,7 @@
+
+ hrtimer_init_on_stack(&t.timer, clockid, mode);
+ hrtimer_set_expires_range_ns(&t.timer, timespec_to_ktime(*rqtp), slack);
+- if (do_nanosleep(&t, mode))
++ if (do_nanosleep(&t, mode, state))
+ goto out;
+
+ /* Absolute timers do not update the rmtp value and restart: */
+@@ -1573,6 +1758,12 @@
+ return ret;
+ }
+
++long hrtimer_nanosleep(struct timespec *rqtp, struct timespec __user *rmtp,
++ const enum hrtimer_mode mode, const clockid_t clockid)
++{
++ return __hrtimer_nanosleep(rqtp, rmtp, mode, clockid, TASK_INTERRUPTIBLE);
++}
++
+ SYSCALL_DEFINE2(nanosleep, struct timespec __user *, rqtp,
+ struct timespec __user *, rmtp)
+ {
+@@ -1587,6 +1778,26 @@
+ return hrtimer_nanosleep(&tu, rmtp, HRTIMER_MODE_REL, CLOCK_MONOTONIC);
+ }
+
++#ifdef CONFIG_PREEMPT_RT_FULL
++/*
++ * Sleep for 1 ms in hope whoever holds what we want will let it go.
++ */
++void cpu_chill(void)
++{
++ struct timespec tu = {
++ .tv_nsec = NSEC_PER_MSEC,
++ };
++ unsigned int freeze_flag = current->flags & PF_NOFREEZE;
++
++ current->flags |= PF_NOFREEZE;
++ __hrtimer_nanosleep(&tu, NULL, HRTIMER_MODE_REL, CLOCK_MONOTONIC,
++ TASK_UNINTERRUPTIBLE);
++ if (!freeze_flag)
++ current->flags &= ~PF_NOFREEZE;
++}
++EXPORT_SYMBOL(cpu_chill);
++#endif
++
+ /*
+ * Functions related to boot-time initialization:
+ */
+@@ -1598,10 +1809,14 @@
+ for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++) {
+ cpu_base->clock_base[i].cpu_base = cpu_base;
+ timerqueue_init_head(&cpu_base->clock_base[i].active);
++ INIT_LIST_HEAD(&cpu_base->clock_base[i].expired);
+ }
+
+ cpu_base->cpu = cpu;
+ hrtimer_init_hres(cpu_base);
++#ifdef CONFIG_PREEMPT_RT_BASE
++ init_waitqueue_head(&cpu_base->wait);
++#endif
+ return 0;
+ }
+
+@@ -1671,9 +1886,26 @@
+
+ #endif /* CONFIG_HOTPLUG_CPU */
+
++#ifdef CONFIG_PREEMPT_RT_BASE
++
++static void run_hrtimer_softirq(struct softirq_action *h)
++{
++ hrtimer_rt_run_pending();
++}
++
++static void hrtimers_open_softirq(void)
++{
++ open_softirq(HRTIMER_SOFTIRQ, run_hrtimer_softirq);
++}
++
++#else
++static void hrtimers_open_softirq(void) { }
++#endif
++
+ void __init hrtimers_init(void)
+ {
+ hrtimers_prepare_cpu(smp_processor_id());
++ hrtimers_open_softirq();
+ }
+
+ /**
+diff -Nur linux-4.8.15.orig/kernel/time/itimer.c linux-4.8.15/kernel/time/itimer.c
+--- linux-4.8.15.orig/kernel/time/itimer.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/time/itimer.c 2017-01-01 17:07:16.047427991 +0100
+@@ -213,6 +213,7 @@
+ /* We are sharing ->siglock with it_real_fn() */
+ if (hrtimer_try_to_cancel(timer) < 0) {
+ spin_unlock_irq(&tsk->sighand->siglock);
++ hrtimer_wait_for_timer(&tsk->signal->real_timer);
+ goto again;
+ }
+ expires = timeval_to_ktime(value->it_value);
+diff -Nur linux-4.8.15.orig/kernel/time/jiffies.c linux-4.8.15/kernel/time/jiffies.c
+--- linux-4.8.15.orig/kernel/time/jiffies.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/time/jiffies.c 2017-01-01 17:07:16.047427991 +0100
+@@ -74,7 +74,8 @@
+ .max_cycles = 10,
+ };
+
+-__cacheline_aligned_in_smp DEFINE_SEQLOCK(jiffies_lock);
++__cacheline_aligned_in_smp DEFINE_RAW_SPINLOCK(jiffies_lock);
++__cacheline_aligned_in_smp seqcount_t jiffies_seq;
+
+ #if (BITS_PER_LONG < 64)
+ u64 get_jiffies_64(void)
+@@ -83,9 +84,9 @@
+ u64 ret;
+
+ do {
+- seq = read_seqbegin(&jiffies_lock);
++ seq = read_seqcount_begin(&jiffies_seq);
+ ret = jiffies_64;
+- } while (read_seqretry(&jiffies_lock, seq));
++ } while (read_seqcount_retry(&jiffies_seq, seq));
+ return ret;
+ }
+ EXPORT_SYMBOL(get_jiffies_64);
+diff -Nur linux-4.8.15.orig/kernel/time/ntp.c linux-4.8.15/kernel/time/ntp.c
+--- linux-4.8.15.orig/kernel/time/ntp.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/time/ntp.c 2017-01-01 17:07:16.047427991 +0100
+@@ -17,6 +17,7 @@
+ #include <linux/module.h>
+ #include <linux/rtc.h>
+ #include <linux/math64.h>
++#include <linux/swork.h>
+
+ #include "ntp_internal.h"
+ #include "timekeeping_internal.h"
+@@ -568,10 +569,35 @@
+ &sync_cmos_work, timespec64_to_jiffies(&next));
+ }
+
++#ifdef CONFIG_PREEMPT_RT_FULL
++
++static void run_clock_set_delay(struct swork_event *event)
++{
++ queue_delayed_work(system_power_efficient_wq, &sync_cmos_work, 0);
++}
++
++static struct swork_event ntp_cmos_swork;
++
++void ntp_notify_cmos_timer(void)
++{
++ swork_queue(&ntp_cmos_swork);
++}
++
++static __init int create_cmos_delay_thread(void)
++{
++ WARN_ON(swork_get());
++ INIT_SWORK(&ntp_cmos_swork, run_clock_set_delay);
++ return 0;
++}
++early_initcall(create_cmos_delay_thread);
++
++#else
++
+ void ntp_notify_cmos_timer(void)
+ {
+ queue_delayed_work(system_power_efficient_wq, &sync_cmos_work, 0);
+ }
++#endif /* CONFIG_PREEMPT_RT_FULL */
+
+ #else
+ void ntp_notify_cmos_timer(void) { }
+diff -Nur linux-4.8.15.orig/kernel/time/posix-cpu-timers.c linux-4.8.15/kernel/time/posix-cpu-timers.c
+--- linux-4.8.15.orig/kernel/time/posix-cpu-timers.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/time/posix-cpu-timers.c 2017-01-01 17:07:16.047427991 +0100
+@@ -3,6 +3,7 @@
+ */
+
+ #include <linux/sched.h>
++#include <linux/sched/rt.h>
+ #include <linux/posix-timers.h>
+ #include <linux/errno.h>
+ #include <linux/math64.h>
+@@ -620,7 +621,7 @@
+ /*
+ * Disarm any old timer after extracting its expiry time.
+ */
+- WARN_ON_ONCE(!irqs_disabled());
++ WARN_ON_ONCE_NONRT(!irqs_disabled());
+
+ ret = 0;
+ old_incr = timer->it.cpu.incr;
+@@ -1064,7 +1065,7 @@
+ /*
+ * Now re-arm for the new expiry time.
+ */
+- WARN_ON_ONCE(!irqs_disabled());
++ WARN_ON_ONCE_NONRT(!irqs_disabled());
+ arm_timer(timer);
+ unlock_task_sighand(p, &flags);
+
+@@ -1153,13 +1154,13 @@
+ * already updated our counts. We need to check if any timers fire now.
+ * Interrupts are disabled.
+ */
+-void run_posix_cpu_timers(struct task_struct *tsk)
++static void __run_posix_cpu_timers(struct task_struct *tsk)
+ {
+ LIST_HEAD(firing);
+ struct k_itimer *timer, *next;
+ unsigned long flags;
+
+- WARN_ON_ONCE(!irqs_disabled());
++ WARN_ON_ONCE_NONRT(!irqs_disabled());
+
+ /*
+ * The fast path checks that there are no expired thread or thread
+@@ -1213,6 +1214,190 @@
+ }
+ }
+
++#ifdef CONFIG_PREEMPT_RT_BASE
++#include <linux/kthread.h>
++#include <linux/cpu.h>
++DEFINE_PER_CPU(struct task_struct *, posix_timer_task);
++DEFINE_PER_CPU(struct task_struct *, posix_timer_tasklist);
++
++static int posix_cpu_timers_thread(void *data)
++{
++ int cpu = (long)data;
++
++ BUG_ON(per_cpu(posix_timer_task,cpu) != current);
++
++ while (!kthread_should_stop()) {
++ struct task_struct *tsk = NULL;
++ struct task_struct *next = NULL;
++
++ if (cpu_is_offline(cpu))
++ goto wait_to_die;
++
++ /* grab task list */
++ raw_local_irq_disable();
++ tsk = per_cpu(posix_timer_tasklist, cpu);
++ per_cpu(posix_timer_tasklist, cpu) = NULL;
++ raw_local_irq_enable();
++
++ /* its possible the list is empty, just return */
++ if (!tsk) {
++ set_current_state(TASK_INTERRUPTIBLE);
++ schedule();
++ __set_current_state(TASK_RUNNING);
++ continue;
++ }
++
++ /* Process task list */
++ while (1) {
++ /* save next */
++ next = tsk->posix_timer_list;
++
++ /* run the task timers, clear its ptr and
++ * unreference it
++ */
++ __run_posix_cpu_timers(tsk);
++ tsk->posix_timer_list = NULL;
++ put_task_struct(tsk);
++
++ /* check if this is the last on the list */
++ if (next == tsk)
++ break;
++ tsk = next;
++ }
++ }
++ return 0;
++
++wait_to_die:
++ /* Wait for kthread_stop */
++ set_current_state(TASK_INTERRUPTIBLE);
++ while (!kthread_should_stop()) {
++ schedule();
++ set_current_state(TASK_INTERRUPTIBLE);
++ }
++ __set_current_state(TASK_RUNNING);
++ return 0;
++}
++
++static inline int __fastpath_timer_check(struct task_struct *tsk)
++{
++ /* tsk == current, ensure it is safe to use ->signal/sighand */
++ if (unlikely(tsk->exit_state))
++ return 0;
++
++ if (!task_cputime_zero(&tsk->cputime_expires))
++ return 1;
++
++ if (!task_cputime_zero(&tsk->signal->cputime_expires))
++ return 1;
++
++ return 0;
++}
++
++void run_posix_cpu_timers(struct task_struct *tsk)
++{
++ unsigned long cpu = smp_processor_id();
++ struct task_struct *tasklist;
++
++ BUG_ON(!irqs_disabled());
++ if(!per_cpu(posix_timer_task, cpu))
++ return;
++ /* get per-cpu references */
++ tasklist = per_cpu(posix_timer_tasklist, cpu);
++
++ /* check to see if we're already queued */
++ if (!tsk->posix_timer_list && __fastpath_timer_check(tsk)) {
++ get_task_struct(tsk);
++ if (tasklist) {
++ tsk->posix_timer_list = tasklist;
++ } else {
++ /*
++ * The list is terminated by a self-pointing
++ * task_struct
++ */
++ tsk->posix_timer_list = tsk;
++ }
++ per_cpu(posix_timer_tasklist, cpu) = tsk;
++
++ wake_up_process(per_cpu(posix_timer_task, cpu));
++ }
++}
++
++/*
++ * posix_cpu_thread_call - callback that gets triggered when a CPU is added.
++ * Here we can start up the necessary migration thread for the new CPU.
++ */
++static int posix_cpu_thread_call(struct notifier_block *nfb,
++ unsigned long action, void *hcpu)
++{
++ int cpu = (long)hcpu;
++ struct task_struct *p;
++ struct sched_param param;
++
++ switch (action) {
++ case CPU_UP_PREPARE:
++ p = kthread_create(posix_cpu_timers_thread, hcpu,
++ "posixcputmr/%d",cpu);
++ if (IS_ERR(p))
++ return NOTIFY_BAD;
++ p->flags |= PF_NOFREEZE;
++ kthread_bind(p, cpu);
++ /* Must be high prio to avoid getting starved */
++ param.sched_priority = MAX_RT_PRIO-1;
++ sched_setscheduler(p, SCHED_FIFO, &param);
++ per_cpu(posix_timer_task,cpu) = p;
++ break;
++ case CPU_ONLINE:
++ /* Strictly unneccessary, as first user will wake it. */
++ wake_up_process(per_cpu(posix_timer_task,cpu));
++ break;
++#ifdef CONFIG_HOTPLUG_CPU
++ case CPU_UP_CANCELED:
++ /* Unbind it from offline cpu so it can run. Fall thru. */
++ kthread_bind(per_cpu(posix_timer_task, cpu),
++ cpumask_any(cpu_online_mask));
++ kthread_stop(per_cpu(posix_timer_task,cpu));
++ per_cpu(posix_timer_task,cpu) = NULL;
++ break;
++ case CPU_DEAD:
++ kthread_stop(per_cpu(posix_timer_task,cpu));
++ per_cpu(posix_timer_task,cpu) = NULL;
++ break;
++#endif
++ }
++ return NOTIFY_OK;
++}
++
++/* Register at highest priority so that task migration (migrate_all_tasks)
++ * happens before everything else.
++ */
++static struct notifier_block posix_cpu_thread_notifier = {
++ .notifier_call = posix_cpu_thread_call,
++ .priority = 10
++};
++
++static int __init posix_cpu_thread_init(void)
++{
++ void *hcpu = (void *)(long)smp_processor_id();
++ /* Start one for boot CPU. */
++ unsigned long cpu;
++
++ /* init the per-cpu posix_timer_tasklets */
++ for_each_possible_cpu(cpu)
++ per_cpu(posix_timer_tasklist, cpu) = NULL;
++
++ posix_cpu_thread_call(&posix_cpu_thread_notifier, CPU_UP_PREPARE, hcpu);
++ posix_cpu_thread_call(&posix_cpu_thread_notifier, CPU_ONLINE, hcpu);
++ register_cpu_notifier(&posix_cpu_thread_notifier);
++ return 0;
++}
++early_initcall(posix_cpu_thread_init);
++#else /* CONFIG_PREEMPT_RT_BASE */
++void run_posix_cpu_timers(struct task_struct *tsk)
++{
++ __run_posix_cpu_timers(tsk);
++}
++#endif /* CONFIG_PREEMPT_RT_BASE */
++
+ /*
+ * Set one of the process-wide special case CPU timers or RLIMIT_CPU.
+ * The tsk->sighand->siglock must be held by the caller.
+diff -Nur linux-4.8.15.orig/kernel/time/posix-timers.c linux-4.8.15/kernel/time/posix-timers.c
+--- linux-4.8.15.orig/kernel/time/posix-timers.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/time/posix-timers.c 2017-01-01 17:07:16.047427991 +0100
+@@ -506,6 +506,7 @@
+ static struct pid *good_sigevent(sigevent_t * event)
+ {
+ struct task_struct *rtn = current->group_leader;
++ int sig = event->sigev_signo;
+
+ if ((event->sigev_notify & SIGEV_THREAD_ID ) &&
+ (!(rtn = find_task_by_vpid(event->sigev_notify_thread_id)) ||
+@@ -514,7 +515,8 @@
+ return NULL;
+
+ if (((event->sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE) &&
+- ((event->sigev_signo <= 0) || (event->sigev_signo > SIGRTMAX)))
++ (sig <= 0 || sig > SIGRTMAX || sig_kernel_only(sig) ||
++ sig_kernel_coredump(sig)))
+ return NULL;
+
+ return task_pid(rtn);
+@@ -826,6 +828,20 @@
+ return overrun;
+ }
+
++/*
++ * Protected by RCU!
++ */
++static void timer_wait_for_callback(struct k_clock *kc, struct k_itimer *timr)
++{
++#ifdef CONFIG_PREEMPT_RT_FULL
++ if (kc->timer_set == common_timer_set)
++ hrtimer_wait_for_timer(&timr->it.real.timer);
++ else
++ /* FIXME: Whacky hack for posix-cpu-timers */
++ schedule_timeout(1);
++#endif
++}
++
+ /* Set a POSIX.1b interval timer. */
+ /* timr->it_lock is taken. */
+ static int
+@@ -903,6 +919,7 @@
+ if (!timr)
+ return -EINVAL;
+
++ rcu_read_lock();
+ kc = clockid_to_kclock(timr->it_clock);
+ if (WARN_ON_ONCE(!kc || !kc->timer_set))
+ error = -EINVAL;
+@@ -911,9 +928,12 @@
+
+ unlock_timer(timr, flag);
+ if (error == TIMER_RETRY) {
++ timer_wait_for_callback(kc, timr);
+ rtn = NULL; // We already got the old time...
++ rcu_read_unlock();
+ goto retry;
+ }
++ rcu_read_unlock();
+
+ if (old_setting && !error &&
+ copy_to_user(old_setting, &old_spec, sizeof (old_spec)))
+@@ -951,10 +971,15 @@
+ if (!timer)
+ return -EINVAL;
+
++ rcu_read_lock();
+ if (timer_delete_hook(timer) == TIMER_RETRY) {
+ unlock_timer(timer, flags);
++ timer_wait_for_callback(clockid_to_kclock(timer->it_clock),
++ timer);
++ rcu_read_unlock();
+ goto retry_delete;
+ }
++ rcu_read_unlock();
+
+ spin_lock(&current->sighand->siglock);
+ list_del(&timer->list);
+@@ -980,8 +1005,18 @@
+ retry_delete:
+ spin_lock_irqsave(&timer->it_lock, flags);
+
++ /* On RT we can race with a deletion */
++ if (!timer->it_signal) {
++ unlock_timer(timer, flags);
++ return;
++ }
++
+ if (timer_delete_hook(timer) == TIMER_RETRY) {
++ rcu_read_lock();
+ unlock_timer(timer, flags);
++ timer_wait_for_callback(clockid_to_kclock(timer->it_clock),
++ timer);
++ rcu_read_unlock();
+ goto retry_delete;
+ }
+ list_del(&timer->list);
+diff -Nur linux-4.8.15.orig/kernel/time/tick-broadcast-hrtimer.c linux-4.8.15/kernel/time/tick-broadcast-hrtimer.c
+--- linux-4.8.15.orig/kernel/time/tick-broadcast-hrtimer.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/time/tick-broadcast-hrtimer.c 2017-01-01 17:07:16.047427991 +0100
+@@ -107,5 +107,6 @@
+ {
+ hrtimer_init(&bctimer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
+ bctimer.function = bc_handler;
++ bctimer.irqsafe = true;
+ clockevents_register_device(&ce_broadcast_hrtimer);
+ }
+diff -Nur linux-4.8.15.orig/kernel/time/tick-common.c linux-4.8.15/kernel/time/tick-common.c
+--- linux-4.8.15.orig/kernel/time/tick-common.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/time/tick-common.c 2017-01-01 17:07:16.047427991 +0100
+@@ -79,13 +79,15 @@
+ static void tick_periodic(int cpu)
+ {
+ if (tick_do_timer_cpu == cpu) {
+- write_seqlock(&jiffies_lock);
++ raw_spin_lock(&jiffies_lock);
++ write_seqcount_begin(&jiffies_seq);
+
+ /* Keep track of the next tick event */
+ tick_next_period = ktime_add(tick_next_period, tick_period);
+
+ do_timer(1);
+- write_sequnlock(&jiffies_lock);
++ write_seqcount_end(&jiffies_seq);
++ raw_spin_unlock(&jiffies_lock);
+ update_wall_time();
+ }
+
+@@ -157,9 +159,9 @@
+ ktime_t next;
+
+ do {
+- seq = read_seqbegin(&jiffies_lock);
++ seq = read_seqcount_begin(&jiffies_seq);
+ next = tick_next_period;
+- } while (read_seqretry(&jiffies_lock, seq));
++ } while (read_seqcount_retry(&jiffies_seq, seq));
+
+ clockevents_switch_state(dev, CLOCK_EVT_STATE_ONESHOT);
+
+diff -Nur linux-4.8.15.orig/kernel/time/tick-sched.c linux-4.8.15/kernel/time/tick-sched.c
+--- linux-4.8.15.orig/kernel/time/tick-sched.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/time/tick-sched.c 2017-01-01 17:07:16.047427991 +0100
+@@ -62,7 +62,8 @@
+ return;
+
+ /* Reevaluate with jiffies_lock held */
+- write_seqlock(&jiffies_lock);
++ raw_spin_lock(&jiffies_lock);
++ write_seqcount_begin(&jiffies_seq);
+
+ delta = ktime_sub(now, last_jiffies_update);
+ if (delta.tv64 >= tick_period.tv64) {
+@@ -85,10 +86,12 @@
+ /* Keep the tick_next_period variable up to date */
+ tick_next_period = ktime_add(last_jiffies_update, tick_period);
+ } else {
+- write_sequnlock(&jiffies_lock);
++ write_seqcount_end(&jiffies_seq);
++ raw_spin_unlock(&jiffies_lock);
+ return;
+ }
+- write_sequnlock(&jiffies_lock);
++ write_seqcount_end(&jiffies_seq);
++ raw_spin_unlock(&jiffies_lock);
+ update_wall_time();
+ }
+
+@@ -99,12 +102,14 @@
+ {
+ ktime_t period;
+
+- write_seqlock(&jiffies_lock);
++ raw_spin_lock(&jiffies_lock);
++ write_seqcount_begin(&jiffies_seq);
+ /* Did we start the jiffies update yet ? */
+ if (last_jiffies_update.tv64 == 0)
+ last_jiffies_update = tick_next_period;
+ period = last_jiffies_update;
+- write_sequnlock(&jiffies_lock);
++ write_seqcount_end(&jiffies_seq);
++ raw_spin_unlock(&jiffies_lock);
+ return period;
+ }
+
+@@ -212,6 +217,7 @@
+
+ static DEFINE_PER_CPU(struct irq_work, nohz_full_kick_work) = {
+ .func = nohz_full_kick_func,
++ .flags = IRQ_WORK_HARD_IRQ,
+ };
+
+ /*
+@@ -670,10 +676,10 @@
+
+ /* Read jiffies and the time when jiffies were updated last */
+ do {
+- seq = read_seqbegin(&jiffies_lock);
++ seq = read_seqcount_begin(&jiffies_seq);
+ basemono = last_jiffies_update.tv64;
+ basejiff = jiffies;
+- } while (read_seqretry(&jiffies_lock, seq));
++ } while (read_seqcount_retry(&jiffies_seq, seq));
+ ts->last_jiffies = basejiff;
+
+ if (rcu_needs_cpu(basemono, &next_rcu) ||
+@@ -874,14 +880,7 @@
+ return false;
+
+ if (unlikely(local_softirq_pending() && cpu_online(cpu))) {
+- static int ratelimit;
+-
+- if (ratelimit < 10 &&
+- (local_softirq_pending() & SOFTIRQ_STOP_IDLE_MASK)) {
+- pr_warn("NOHZ: local_softirq_pending %02x\n",
+- (unsigned int) local_softirq_pending());
+- ratelimit++;
+- }
++ softirq_check_pending_idle();
+ return false;
+ }
+
+@@ -1190,6 +1189,7 @@
+ * Emulate tick processing via per-CPU hrtimers:
+ */
+ hrtimer_init(&ts->sched_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
++ ts->sched_timer.irqsafe = 1;
+ ts->sched_timer.function = tick_sched_timer;
+
+ /* Get the next period (per-CPU) */
+diff -Nur linux-4.8.15.orig/kernel/time/timekeeping.c linux-4.8.15/kernel/time/timekeeping.c
+--- linux-4.8.15.orig/kernel/time/timekeeping.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/time/timekeeping.c 2017-01-01 17:07:16.051428246 +0100
+@@ -2328,8 +2328,10 @@
+ */
+ void xtime_update(unsigned long ticks)
+ {
+- write_seqlock(&jiffies_lock);
++ raw_spin_lock(&jiffies_lock);
++ write_seqcount_begin(&jiffies_seq);
+ do_timer(ticks);
+- write_sequnlock(&jiffies_lock);
++ write_seqcount_end(&jiffies_seq);
++ raw_spin_unlock(&jiffies_lock);
+ update_wall_time();
+ }
+diff -Nur linux-4.8.15.orig/kernel/time/timekeeping.h linux-4.8.15/kernel/time/timekeeping.h
+--- linux-4.8.15.orig/kernel/time/timekeeping.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/time/timekeeping.h 2017-01-01 17:07:16.051428246 +0100
+@@ -19,7 +19,8 @@
+ extern void do_timer(unsigned long ticks);
+ extern void update_wall_time(void);
+
+-extern seqlock_t jiffies_lock;
++extern raw_spinlock_t jiffies_lock;
++extern seqcount_t jiffies_seq;
+
+ #define CS_NAME_LEN 32
+
+diff -Nur linux-4.8.15.orig/kernel/time/timer.c linux-4.8.15/kernel/time/timer.c
+--- linux-4.8.15.orig/kernel/time/timer.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/time/timer.c 2017-01-01 17:07:16.051428246 +0100
+@@ -193,8 +193,11 @@
+ #endif
+
+ struct timer_base {
+- spinlock_t lock;
++ raw_spinlock_t lock;
+ struct timer_list *running_timer;
++#ifdef CONFIG_PREEMPT_RT_FULL
++ struct swait_queue_head wait_for_running_timer;
++#endif
+ unsigned long clk;
+ unsigned long next_expiry;
+ unsigned int cpu;
+@@ -948,10 +951,10 @@
+
+ if (!(tf & TIMER_MIGRATING)) {
+ base = get_timer_base(tf);
+- spin_lock_irqsave(&base->lock, *flags);
++ raw_spin_lock_irqsave(&base->lock, *flags);
+ if (timer->flags == tf)
+ return base;
+- spin_unlock_irqrestore(&base->lock, *flags);
++ raw_spin_unlock_irqrestore(&base->lock, *flags);
+ }
+ cpu_relax();
+ }
+@@ -1023,9 +1026,9 @@
+ /* See the comment in lock_timer_base() */
+ timer->flags |= TIMER_MIGRATING;
+
+- spin_unlock(&base->lock);
++ raw_spin_unlock(&base->lock);
+ base = new_base;
+- spin_lock(&base->lock);
++ raw_spin_lock(&base->lock);
+ WRITE_ONCE(timer->flags,
+ (timer->flags & ~TIMER_BASEMASK) | base->cpu);
+ }
+@@ -1050,7 +1053,7 @@
+ }
+
+ out_unlock:
+- spin_unlock_irqrestore(&base->lock, flags);
++ raw_spin_unlock_irqrestore(&base->lock, flags);
+
+ return ret;
+ }
+@@ -1144,19 +1147,46 @@
+ if (base != new_base) {
+ timer->flags |= TIMER_MIGRATING;
+
+- spin_unlock(&base->lock);
++ raw_spin_unlock(&base->lock);
+ base = new_base;
+- spin_lock(&base->lock);
++ raw_spin_lock(&base->lock);
+ WRITE_ONCE(timer->flags,
+ (timer->flags & ~TIMER_BASEMASK) | cpu);
+ }
+
+ debug_activate(timer, timer->expires);
+ internal_add_timer(base, timer);
+- spin_unlock_irqrestore(&base->lock, flags);
++ raw_spin_unlock_irqrestore(&base->lock, flags);
+ }
+ EXPORT_SYMBOL_GPL(add_timer_on);
+
++#ifdef CONFIG_PREEMPT_RT_FULL
++/*
++ * Wait for a running timer
++ */
++static void wait_for_running_timer(struct timer_list *timer)
++{
++ struct timer_base *base;
++ u32 tf = timer->flags;
++
++ if (tf & TIMER_MIGRATING)
++ return;
++
++ base = get_timer_base(tf);
++ swait_event(base->wait_for_running_timer,
++ base->running_timer != timer);
++}
++
++# define wakeup_timer_waiters(b) swake_up_all(&(b)->wait_for_running_timer)
++#else
++static inline void wait_for_running_timer(struct timer_list *timer)
++{
++ cpu_relax();
++}
++
++# define wakeup_timer_waiters(b) do { } while (0)
++#endif
++
+ /**
+ * del_timer - deactive a timer.
+ * @timer: the timer to be deactivated
+@@ -1180,7 +1210,7 @@
+ if (timer_pending(timer)) {
+ base = lock_timer_base(timer, &flags);
+ ret = detach_if_pending(timer, base, true);
+- spin_unlock_irqrestore(&base->lock, flags);
++ raw_spin_unlock_irqrestore(&base->lock, flags);
+ }
+
+ return ret;
+@@ -1208,13 +1238,13 @@
+ timer_stats_timer_clear_start_info(timer);
+ ret = detach_if_pending(timer, base, true);
+ }
+- spin_unlock_irqrestore(&base->lock, flags);
++ raw_spin_unlock_irqrestore(&base->lock, flags);
+
+ return ret;
+ }
+ EXPORT_SYMBOL(try_to_del_timer_sync);
+
+-#ifdef CONFIG_SMP
++#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT_FULL)
+ /**
+ * del_timer_sync - deactivate a timer and wait for the handler to finish.
+ * @timer: the timer to be deactivated
+@@ -1274,7 +1304,7 @@
+ int ret = try_to_del_timer_sync(timer);
+ if (ret >= 0)
+ return ret;
+- cpu_relax();
++ wait_for_running_timer(timer);
+ }
+ }
+ EXPORT_SYMBOL(del_timer_sync);
+@@ -1339,14 +1369,17 @@
+ fn = timer->function;
+ data = timer->data;
+
+- if (timer->flags & TIMER_IRQSAFE) {
+- spin_unlock(&base->lock);
++ if (!IS_ENABLED(CONFIG_PREEMPT_RT_FULL) &&
++ timer->flags & TIMER_IRQSAFE) {
++ raw_spin_unlock(&base->lock);
+ call_timer_fn(timer, fn, data);
+- spin_lock(&base->lock);
++ base->running_timer = NULL;
++ raw_spin_lock(&base->lock);
+ } else {
+- spin_unlock_irq(&base->lock);
++ raw_spin_unlock_irq(&base->lock);
+ call_timer_fn(timer, fn, data);
+- spin_lock_irq(&base->lock);
++ base->running_timer = NULL;
++ raw_spin_lock_irq(&base->lock);
+ }
+ }
+ }
+@@ -1515,7 +1548,7 @@
+ if (cpu_is_offline(smp_processor_id()))
+ return expires;
+
+- spin_lock(&base->lock);
++ raw_spin_lock(&base->lock);
+ nextevt = __next_timer_interrupt(base);
+ is_max_delta = (nextevt == base->clk + NEXT_TIMER_MAX_DELTA);
+ base->next_expiry = nextevt;
+@@ -1543,7 +1576,7 @@
+ if ((expires - basem) > TICK_NSEC)
+ base->is_idle = true;
+ }
+- spin_unlock(&base->lock);
++ raw_spin_unlock(&base->lock);
+
+ return cmp_next_hrtimer_event(basem, expires);
+ }
+@@ -1608,13 +1641,13 @@
+
+ /* Note: this timer irq context must be accounted for as well. */
+ account_process_tick(p, user_tick);
++ scheduler_tick();
+ run_local_timers();
+ rcu_check_callbacks(user_tick);
+-#ifdef CONFIG_IRQ_WORK
++#if defined(CONFIG_IRQ_WORK)
+ if (in_irq())
+ irq_work_tick();
+ #endif
+- scheduler_tick();
+ run_posix_cpu_timers(p);
+ }
+
+@@ -1630,7 +1663,7 @@
+ if (!time_after_eq(jiffies, base->clk))
+ return;
+
+- spin_lock_irq(&base->lock);
++ raw_spin_lock_irq(&base->lock);
+
+ while (time_after_eq(jiffies, base->clk)) {
+
+@@ -1640,8 +1673,8 @@
+ while (levels--)
+ expire_timers(base, heads + levels);
+ }
+- base->running_timer = NULL;
+- spin_unlock_irq(&base->lock);
++ raw_spin_unlock_irq(&base->lock);
++ wakeup_timer_waiters(base);
+ }
+
+ /*
+@@ -1651,6 +1684,8 @@
+ {
+ struct timer_base *base = this_cpu_ptr(&timer_bases[BASE_STD]);
+
++ irq_work_tick_soft();
++
+ __run_timers(base);
+ if (IS_ENABLED(CONFIG_NO_HZ_COMMON) && base->nohz_active)
+ __run_timers(this_cpu_ptr(&timer_bases[BASE_DEF]));
+@@ -1836,16 +1871,16 @@
+ * The caller is globally serialized and nobody else
+ * takes two locks at once, deadlock is not possible.
+ */
+- spin_lock_irq(&new_base->lock);
+- spin_lock_nested(&old_base->lock, SINGLE_DEPTH_NESTING);
++ raw_spin_lock_irq(&new_base->lock);
++ raw_spin_lock_nested(&old_base->lock, SINGLE_DEPTH_NESTING);
+
+ BUG_ON(old_base->running_timer);
+
+ for (i = 0; i < WHEEL_SIZE; i++)
+ migrate_timer_list(new_base, old_base->vectors + i);
+
+- spin_unlock(&old_base->lock);
+- spin_unlock_irq(&new_base->lock);
++ raw_spin_unlock(&old_base->lock);
++ raw_spin_unlock_irq(&new_base->lock);
+ put_cpu_ptr(&timer_bases);
+ }
+ return 0;
+@@ -1861,8 +1896,11 @@
+ for (i = 0; i < NR_BASES; i++) {
+ base = per_cpu_ptr(&timer_bases[i], cpu);
+ base->cpu = cpu;
+- spin_lock_init(&base->lock);
++ raw_spin_lock_init(&base->lock);
+ base->clk = jiffies;
++#ifdef CONFIG_PREEMPT_RT_FULL
++ init_swait_queue_head(&base->wait_for_running_timer);
++#endif
+ }
+ }
+
+diff -Nur linux-4.8.15.orig/kernel/trace/Kconfig linux-4.8.15/kernel/trace/Kconfig
+--- linux-4.8.15.orig/kernel/trace/Kconfig 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/trace/Kconfig 2017-01-01 17:07:16.051428246 +0100
+@@ -187,6 +187,24 @@
+ enabled. This option and the preempt-off timing option can be
+ used together or separately.)
+
++config INTERRUPT_OFF_HIST
++ bool "Interrupts-off Latency Histogram"
++ depends on IRQSOFF_TRACER
++ help
++ This option generates continuously updated histograms (one per cpu)
++ of the duration of time periods with interrupts disabled. The
++ histograms are disabled by default. To enable them, write a non-zero
++ number to
++
++ /sys/kernel/debug/tracing/latency_hist/enable/preemptirqsoff
++
++ If PREEMPT_OFF_HIST is also selected, additional histograms (one
++ per cpu) are generated that accumulate the duration of time periods
++ when both interrupts and preemption are disabled. The histogram data
++ will be located in the debug file system at
++
++ /sys/kernel/debug/tracing/latency_hist/irqsoff
++
+ config PREEMPT_TRACER
+ bool "Preemption-off Latency Tracer"
+ default n
+@@ -197,6 +215,7 @@
+ select RING_BUFFER_ALLOW_SWAP
+ select TRACER_SNAPSHOT
+ select TRACER_SNAPSHOT_PER_CPU_SWAP
++ select USING_GET_LOCK_PARENT_IP
+ help
+ This option measures the time spent in preemption-off critical
+ sections, with microsecond accuracy.
+@@ -211,6 +230,24 @@
+ enabled. This option and the irqs-off timing option can be
+ used together or separately.)
+
++config PREEMPT_OFF_HIST
++ bool "Preemption-off Latency Histogram"
++ depends on PREEMPT_TRACER
++ help
++ This option generates continuously updated histograms (one per cpu)
++ of the duration of time periods with preemption disabled. The
++ histograms are disabled by default. To enable them, write a non-zero
++ number to
++
++ /sys/kernel/debug/tracing/latency_hist/enable/preemptirqsoff
++
++ If INTERRUPT_OFF_HIST is also selected, additional histograms (one
++ per cpu) are generated that accumulate the duration of time periods
++ when both interrupts and preemption are disabled. The histogram data
++ will be located in the debug file system at
++
++ /sys/kernel/debug/tracing/latency_hist/preemptoff
++
+ config SCHED_TRACER
+ bool "Scheduling Latency Tracer"
+ select GENERIC_TRACER
+@@ -221,6 +258,74 @@
+ This tracer tracks the latency of the highest priority task
+ to be scheduled in, starting from the point it has woken up.
+
++config WAKEUP_LATENCY_HIST
++ bool "Scheduling Latency Histogram"
++ depends on SCHED_TRACER
++ help
++ This option generates continuously updated histograms (one per cpu)
++ of the scheduling latency of the highest priority task.
++ The histograms are disabled by default. To enable them, write a
++ non-zero number to
++
++ /sys/kernel/debug/tracing/latency_hist/enable/wakeup
++
++ Two different algorithms are used, one to determine the latency of
++ processes that exclusively use the highest priority of the system and
++ another one to determine the latency of processes that share the
++ highest system priority with other processes. The former is used to
++ improve hardware and system software, the latter to optimize the
++ priority design of a given system. The histogram data will be
++ located in the debug file system at
++
++ /sys/kernel/debug/tracing/latency_hist/wakeup
++
++ and
++
++ /sys/kernel/debug/tracing/latency_hist/wakeup/sharedprio
++
++ If both Scheduling Latency Histogram and Missed Timer Offsets
++ Histogram are selected, additional histogram data will be collected
++ that contain, in addition to the wakeup latency, the timer latency, in
++ case the wakeup was triggered by an expired timer. These histograms
++ are available in the
++
++ /sys/kernel/debug/tracing/latency_hist/timerandwakeup
++
++ directory. They reflect the apparent interrupt and scheduling latency
++ and are best suitable to determine the worst-case latency of a given
++ system. To enable these histograms, write a non-zero number to
++
++ /sys/kernel/debug/tracing/latency_hist/enable/timerandwakeup
++
++config MISSED_TIMER_OFFSETS_HIST
++ depends on HIGH_RES_TIMERS
++ select GENERIC_TRACER
++ bool "Missed Timer Offsets Histogram"
++ help
++ Generate a histogram of missed timer offsets in microseconds. The
++ histograms are disabled by default. To enable them, write a non-zero
++ number to
++
++ /sys/kernel/debug/tracing/latency_hist/enable/missed_timer_offsets
++
++ The histogram data will be located in the debug file system at
++
++ /sys/kernel/debug/tracing/latency_hist/missed_timer_offsets
++
++ If both Scheduling Latency Histogram and Missed Timer Offsets
++ Histogram are selected, additional histogram data will be collected
++ that contain, in addition to the wakeup latency, the timer latency, in
++ case the wakeup was triggered by an expired timer. These histograms
++ are available in the
++
++ /sys/kernel/debug/tracing/latency_hist/timerandwakeup
++
++ directory. They reflect the apparent interrupt and scheduling latency
++ and are best suitable to determine the worst-case latency of a given
++ system. To enable these histograms, write a non-zero number to
++
++ /sys/kernel/debug/tracing/latency_hist/enable/timerandwakeup
++
+ config ENABLE_DEFAULT_TRACERS
+ bool "Trace process context switches and events"
+ depends on !GENERIC_TRACER
+diff -Nur linux-4.8.15.orig/kernel/trace/latency_hist.c linux-4.8.15/kernel/trace/latency_hist.c
+--- linux-4.8.15.orig/kernel/trace/latency_hist.c 1970-01-01 01:00:00.000000000 +0100
++++ linux-4.8.15/kernel/trace/latency_hist.c 2017-01-01 17:07:16.051428246 +0100
+@@ -0,0 +1,1178 @@
++/*
++ * kernel/trace/latency_hist.c
++ *
++ * Add support for histograms of preemption-off latency and
++ * interrupt-off latency and wakeup latency, it depends on
++ * Real-Time Preemption Support.
++ *
++ * Copyright (C) 2005 MontaVista Software, Inc.
++ * Yi Yang <yyang@ch.mvista.com>
++ *
++ * Converted to work with the new latency tracer.
++ * Copyright (C) 2008 Red Hat, Inc.
++ * Steven Rostedt <srostedt@redhat.com>
++ *
++ */
++#include <linux/module.h>
++#include <linux/debugfs.h>
++#include <linux/seq_file.h>
++#include <linux/percpu.h>
++#include <linux/kallsyms.h>
++#include <linux/uaccess.h>
++#include <linux/sched.h>
++#include <linux/sched/rt.h>
++#include <linux/slab.h>
++#include <linux/atomic.h>
++#include <asm/div64.h>
++
++#include "trace.h"
++#include <trace/events/sched.h>
++
++#define NSECS_PER_USECS 1000L
++
++#define CREATE_TRACE_POINTS
++#include <trace/events/hist.h>
++
++enum {
++ IRQSOFF_LATENCY = 0,
++ PREEMPTOFF_LATENCY,
++ PREEMPTIRQSOFF_LATENCY,
++ WAKEUP_LATENCY,
++ WAKEUP_LATENCY_SHAREDPRIO,
++ MISSED_TIMER_OFFSETS,
++ TIMERANDWAKEUP_LATENCY,
++ MAX_LATENCY_TYPE,
++};
++
++#define MAX_ENTRY_NUM 10240
++
++struct hist_data {
++ atomic_t hist_mode; /* 0 log, 1 don't log */
++ long offset; /* set it to MAX_ENTRY_NUM/2 for a bipolar scale */
++ long min_lat;
++ long max_lat;
++ unsigned long long below_hist_bound_samples;
++ unsigned long long above_hist_bound_samples;
++ long long accumulate_lat;
++ unsigned long long total_samples;
++ unsigned long long hist_array[MAX_ENTRY_NUM];
++};
++
++struct enable_data {
++ int latency_type;
++ int enabled;
++};
++
++static char *latency_hist_dir_root = "latency_hist";
++
++#ifdef CONFIG_INTERRUPT_OFF_HIST
++static DEFINE_PER_CPU(struct hist_data, irqsoff_hist);
++static char *irqsoff_hist_dir = "irqsoff";
++static DEFINE_PER_CPU(cycles_t, hist_irqsoff_start);
++static DEFINE_PER_CPU(int, hist_irqsoff_counting);
++#endif
++
++#ifdef CONFIG_PREEMPT_OFF_HIST
++static DEFINE_PER_CPU(struct hist_data, preemptoff_hist);
++static char *preemptoff_hist_dir = "preemptoff";
++static DEFINE_PER_CPU(cycles_t, hist_preemptoff_start);
++static DEFINE_PER_CPU(int, hist_preemptoff_counting);
++#endif
++
++#if defined(CONFIG_PREEMPT_OFF_HIST) && defined(CONFIG_INTERRUPT_OFF_HIST)
++static DEFINE_PER_CPU(struct hist_data, preemptirqsoff_hist);
++static char *preemptirqsoff_hist_dir = "preemptirqsoff";
++static DEFINE_PER_CPU(cycles_t, hist_preemptirqsoff_start);
++static DEFINE_PER_CPU(int, hist_preemptirqsoff_counting);
++#endif
++
++#if defined(CONFIG_PREEMPT_OFF_HIST) || defined(CONFIG_INTERRUPT_OFF_HIST)
++static notrace void probe_preemptirqsoff_hist(void *v, int reason, int start);
++static struct enable_data preemptirqsoff_enabled_data = {
++ .latency_type = PREEMPTIRQSOFF_LATENCY,
++ .enabled = 0,
++};
++#endif
++
++#if defined(CONFIG_WAKEUP_LATENCY_HIST) || \
++ defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
++struct maxlatproc_data {
++ char comm[FIELD_SIZEOF(struct task_struct, comm)];
++ char current_comm[FIELD_SIZEOF(struct task_struct, comm)];
++ int pid;
++ int current_pid;
++ int prio;
++ int current_prio;
++ long latency;
++ long timeroffset;
++ cycle_t timestamp;
++};
++#endif
++
++#ifdef CONFIG_WAKEUP_LATENCY_HIST
++static DEFINE_PER_CPU(struct hist_data, wakeup_latency_hist);
++static DEFINE_PER_CPU(struct hist_data, wakeup_latency_hist_sharedprio);
++static char *wakeup_latency_hist_dir = "wakeup";
++static char *wakeup_latency_hist_dir_sharedprio = "sharedprio";
++static notrace void probe_wakeup_latency_hist_start(void *v,
++ struct task_struct *p);
++static notrace void probe_wakeup_latency_hist_stop(void *v,
++ bool preempt, struct task_struct *prev, struct task_struct *next);
++static notrace void probe_sched_migrate_task(void *,
++ struct task_struct *task, int cpu);
++static struct enable_data wakeup_latency_enabled_data = {
++ .latency_type = WAKEUP_LATENCY,
++ .enabled = 0,
++};
++static DEFINE_PER_CPU(struct maxlatproc_data, wakeup_maxlatproc);
++static DEFINE_PER_CPU(struct maxlatproc_data, wakeup_maxlatproc_sharedprio);
++static DEFINE_PER_CPU(struct task_struct *, wakeup_task);
++static DEFINE_PER_CPU(int, wakeup_sharedprio);
++static unsigned long wakeup_pid;
++#endif
++
++#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST
++static DEFINE_PER_CPU(struct hist_data, missed_timer_offsets);
++static char *missed_timer_offsets_dir = "missed_timer_offsets";
++static notrace void probe_hrtimer_interrupt(void *v, int cpu,
++ long long offset, struct task_struct *curr, struct task_struct *task);
++static struct enable_data missed_timer_offsets_enabled_data = {
++ .latency_type = MISSED_TIMER_OFFSETS,
++ .enabled = 0,
++};
++static DEFINE_PER_CPU(struct maxlatproc_data, missed_timer_offsets_maxlatproc);
++static unsigned long missed_timer_offsets_pid;
++#endif
++
++#if defined(CONFIG_WAKEUP_LATENCY_HIST) && \
++ defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
++static DEFINE_PER_CPU(struct hist_data, timerandwakeup_latency_hist);
++static char *timerandwakeup_latency_hist_dir = "timerandwakeup";
++static struct enable_data timerandwakeup_enabled_data = {
++ .latency_type = TIMERANDWAKEUP_LATENCY,
++ .enabled = 0,
++};
++static DEFINE_PER_CPU(struct maxlatproc_data, timerandwakeup_maxlatproc);
++#endif
++
++void notrace latency_hist(int latency_type, int cpu, long latency,
++ long timeroffset, cycle_t stop,
++ struct task_struct *p)
++{
++ struct hist_data *my_hist;
++#if defined(CONFIG_WAKEUP_LATENCY_HIST) || \
++ defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
++ struct maxlatproc_data *mp = NULL;
++#endif
++
++ if (!cpu_possible(cpu) || latency_type < 0 ||
++ latency_type >= MAX_LATENCY_TYPE)
++ return;
++
++ switch (latency_type) {
++#ifdef CONFIG_INTERRUPT_OFF_HIST
++ case IRQSOFF_LATENCY:
++ my_hist = &per_cpu(irqsoff_hist, cpu);
++ break;
++#endif
++#ifdef CONFIG_PREEMPT_OFF_HIST
++ case PREEMPTOFF_LATENCY:
++ my_hist = &per_cpu(preemptoff_hist, cpu);
++ break;
++#endif
++#if defined(CONFIG_PREEMPT_OFF_HIST) && defined(CONFIG_INTERRUPT_OFF_HIST)
++ case PREEMPTIRQSOFF_LATENCY:
++ my_hist = &per_cpu(preemptirqsoff_hist, cpu);
++ break;
++#endif
++#ifdef CONFIG_WAKEUP_LATENCY_HIST
++ case WAKEUP_LATENCY:
++ my_hist = &per_cpu(wakeup_latency_hist, cpu);
++ mp = &per_cpu(wakeup_maxlatproc, cpu);
++ break;
++ case WAKEUP_LATENCY_SHAREDPRIO:
++ my_hist = &per_cpu(wakeup_latency_hist_sharedprio, cpu);
++ mp = &per_cpu(wakeup_maxlatproc_sharedprio, cpu);
++ break;
++#endif
++#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST
++ case MISSED_TIMER_OFFSETS:
++ my_hist = &per_cpu(missed_timer_offsets, cpu);
++ mp = &per_cpu(missed_timer_offsets_maxlatproc, cpu);
++ break;
++#endif
++#if defined(CONFIG_WAKEUP_LATENCY_HIST) && \
++ defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
++ case TIMERANDWAKEUP_LATENCY:
++ my_hist = &per_cpu(timerandwakeup_latency_hist, cpu);
++ mp = &per_cpu(timerandwakeup_maxlatproc, cpu);
++ break;
++#endif
++
++ default:
++ return;
++ }
++
++ latency += my_hist->offset;
++
++ if (atomic_read(&my_hist->hist_mode) == 0)
++ return;
++
++ if (latency < 0 || latency >= MAX_ENTRY_NUM) {
++ if (latency < 0)
++ my_hist->below_hist_bound_samples++;
++ else
++ my_hist->above_hist_bound_samples++;
++ } else
++ my_hist->hist_array[latency]++;
++
++ if (unlikely(latency > my_hist->max_lat ||
++ my_hist->min_lat == LONG_MAX)) {
++#if defined(CONFIG_WAKEUP_LATENCY_HIST) || \
++ defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
++ if (latency_type == WAKEUP_LATENCY ||
++ latency_type == WAKEUP_LATENCY_SHAREDPRIO ||
++ latency_type == MISSED_TIMER_OFFSETS ||
++ latency_type == TIMERANDWAKEUP_LATENCY) {
++ strncpy(mp->comm, p->comm, sizeof(mp->comm));
++ strncpy(mp->current_comm, current->comm,
++ sizeof(mp->current_comm));
++ mp->pid = task_pid_nr(p);
++ mp->current_pid = task_pid_nr(current);
++ mp->prio = p->prio;
++ mp->current_prio = current->prio;
++ mp->latency = latency;
++ mp->timeroffset = timeroffset;
++ mp->timestamp = stop;
++ }
++#endif
++ my_hist->max_lat = latency;
++ }
++ if (unlikely(latency < my_hist->min_lat))
++ my_hist->min_lat = latency;
++ my_hist->total_samples++;
++ my_hist->accumulate_lat += latency;
++}
++
++static void *l_start(struct seq_file *m, loff_t *pos)
++{
++ loff_t *index_ptr = NULL;
++ loff_t index = *pos;
++ struct hist_data *my_hist = m->private;
++
++ if (index == 0) {
++ char minstr[32], avgstr[32], maxstr[32];
++
++ atomic_dec(&my_hist->hist_mode);
++
++ if (likely(my_hist->total_samples)) {
++ long avg = (long) div64_s64(my_hist->accumulate_lat,
++ my_hist->total_samples);
++ snprintf(minstr, sizeof(minstr), "%ld",
++ my_hist->min_lat - my_hist->offset);
++ snprintf(avgstr, sizeof(avgstr), "%ld",
++ avg - my_hist->offset);
++ snprintf(maxstr, sizeof(maxstr), "%ld",
++ my_hist->max_lat - my_hist->offset);
++ } else {
++ strcpy(minstr, "<undef>");
++ strcpy(avgstr, minstr);
++ strcpy(maxstr, minstr);
++ }
++
++ seq_printf(m, "#Minimum latency: %s microseconds\n"
++ "#Average latency: %s microseconds\n"
++ "#Maximum latency: %s microseconds\n"
++ "#Total samples: %llu\n"
++ "#There are %llu samples lower than %ld"
++ " microseconds.\n"
++ "#There are %llu samples greater or equal"
++ " than %ld microseconds.\n"
++ "#usecs\t%16s\n",
++ minstr, avgstr, maxstr,
++ my_hist->total_samples,
++ my_hist->below_hist_bound_samples,
++ -my_hist->offset,
++ my_hist->above_hist_bound_samples,
++ MAX_ENTRY_NUM - my_hist->offset,
++ "samples");
++ }
++ if (index < MAX_ENTRY_NUM) {
++ index_ptr = kmalloc(sizeof(loff_t), GFP_KERNEL);
++ if (index_ptr)
++ *index_ptr = index;
++ }
++
++ return index_ptr;
++}
++
++static void *l_next(struct seq_file *m, void *p, loff_t *pos)
++{
++ loff_t *index_ptr = p;
++ struct hist_data *my_hist = m->private;
++
++ if (++*pos >= MAX_ENTRY_NUM) {
++ atomic_inc(&my_hist->hist_mode);
++ return NULL;
++ }
++ *index_ptr = *pos;
++ return index_ptr;
++}
++
++static void l_stop(struct seq_file *m, void *p)
++{
++ kfree(p);
++}
++
++static int l_show(struct seq_file *m, void *p)
++{
++ int index = *(loff_t *) p;
++ struct hist_data *my_hist = m->private;
++
++ seq_printf(m, "%6ld\t%16llu\n", index - my_hist->offset,
++ my_hist->hist_array[index]);
++ return 0;
++}
++
++static const struct seq_operations latency_hist_seq_op = {
++ .start = l_start,
++ .next = l_next,
++ .stop = l_stop,
++ .show = l_show
++};
++
++static int latency_hist_open(struct inode *inode, struct file *file)
++{
++ int ret;
++
++ ret = seq_open(file, &latency_hist_seq_op);
++ if (!ret) {
++ struct seq_file *seq = file->private_data;
++ seq->private = inode->i_private;
++ }
++ return ret;
++}
++
++static const struct file_operations latency_hist_fops = {
++ .open = latency_hist_open,
++ .read = seq_read,
++ .llseek = seq_lseek,
++ .release = seq_release,
++};
++
++#if defined(CONFIG_WAKEUP_LATENCY_HIST) || \
++ defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
++static void clear_maxlatprocdata(struct maxlatproc_data *mp)
++{
++ mp->comm[0] = mp->current_comm[0] = '\0';
++ mp->prio = mp->current_prio = mp->pid = mp->current_pid =
++ mp->latency = mp->timeroffset = -1;
++ mp->timestamp = 0;
++}
++#endif
++
++static void hist_reset(struct hist_data *hist)
++{
++ atomic_dec(&hist->hist_mode);
++
++ memset(hist->hist_array, 0, sizeof(hist->hist_array));
++ hist->below_hist_bound_samples = 0ULL;
++ hist->above_hist_bound_samples = 0ULL;
++ hist->min_lat = LONG_MAX;
++ hist->max_lat = LONG_MIN;
++ hist->total_samples = 0ULL;
++ hist->accumulate_lat = 0LL;
++
++ atomic_inc(&hist->hist_mode);
++}
++
++static ssize_t
++latency_hist_reset(struct file *file, const char __user *a,
++ size_t size, loff_t *off)
++{
++ int cpu;
++ struct hist_data *hist = NULL;
++#if defined(CONFIG_WAKEUP_LATENCY_HIST) || \
++ defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
++ struct maxlatproc_data *mp = NULL;
++#endif
++ off_t latency_type = (off_t) file->private_data;
++
++ for_each_online_cpu(cpu) {
++
++ switch (latency_type) {
++#ifdef CONFIG_PREEMPT_OFF_HIST
++ case PREEMPTOFF_LATENCY:
++ hist = &per_cpu(preemptoff_hist, cpu);
++ break;
++#endif
++#ifdef CONFIG_INTERRUPT_OFF_HIST
++ case IRQSOFF_LATENCY:
++ hist = &per_cpu(irqsoff_hist, cpu);
++ break;
++#endif
++#if defined(CONFIG_INTERRUPT_OFF_HIST) && defined(CONFIG_PREEMPT_OFF_HIST)
++ case PREEMPTIRQSOFF_LATENCY:
++ hist = &per_cpu(preemptirqsoff_hist, cpu);
++ break;
++#endif
++#ifdef CONFIG_WAKEUP_LATENCY_HIST
++ case WAKEUP_LATENCY:
++ hist = &per_cpu(wakeup_latency_hist, cpu);
++ mp = &per_cpu(wakeup_maxlatproc, cpu);
++ break;
++ case WAKEUP_LATENCY_SHAREDPRIO:
++ hist = &per_cpu(wakeup_latency_hist_sharedprio, cpu);
++ mp = &per_cpu(wakeup_maxlatproc_sharedprio, cpu);
++ break;
++#endif
++#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST
++ case MISSED_TIMER_OFFSETS:
++ hist = &per_cpu(missed_timer_offsets, cpu);
++ mp = &per_cpu(missed_timer_offsets_maxlatproc, cpu);
++ break;
++#endif
++#if defined(CONFIG_WAKEUP_LATENCY_HIST) && \
++ defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
++ case TIMERANDWAKEUP_LATENCY:
++ hist = &per_cpu(timerandwakeup_latency_hist, cpu);
++ mp = &per_cpu(timerandwakeup_maxlatproc, cpu);
++ break;
++#endif
++ }
++
++ hist_reset(hist);
++#if defined(CONFIG_WAKEUP_LATENCY_HIST) || \
++ defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
++ if (latency_type == WAKEUP_LATENCY ||
++ latency_type == WAKEUP_LATENCY_SHAREDPRIO ||
++ latency_type == MISSED_TIMER_OFFSETS ||
++ latency_type == TIMERANDWAKEUP_LATENCY)
++ clear_maxlatprocdata(mp);
++#endif
++ }
++
++ return size;
++}
++
++#if defined(CONFIG_WAKEUP_LATENCY_HIST) || \
++ defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
++static ssize_t
++show_pid(struct file *file, char __user *ubuf, size_t cnt, loff_t *ppos)
++{
++ char buf[64];
++ int r;
++ unsigned long *this_pid = file->private_data;
++
++ r = snprintf(buf, sizeof(buf), "%lu\n", *this_pid);
++ return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
++}
++
++static ssize_t do_pid(struct file *file, const char __user *ubuf,
++ size_t cnt, loff_t *ppos)
++{
++ char buf[64];
++ unsigned long pid;
++ unsigned long *this_pid = file->private_data;
++
++ if (cnt >= sizeof(buf))
++ return -EINVAL;
++
++ if (copy_from_user(&buf, ubuf, cnt))
++ return -EFAULT;
++
++ buf[cnt] = '\0';
++
++ if (kstrtoul(buf, 10, &pid))
++ return -EINVAL;
++
++ *this_pid = pid;
++
++ return cnt;
++}
++#endif
++
++#if defined(CONFIG_WAKEUP_LATENCY_HIST) || \
++ defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
++static ssize_t
++show_maxlatproc(struct file *file, char __user *ubuf, size_t cnt, loff_t *ppos)
++{
++ int r;
++ struct maxlatproc_data *mp = file->private_data;
++ int strmaxlen = (TASK_COMM_LEN * 2) + (8 * 8);
++ unsigned long long t;
++ unsigned long usecs, secs;
++ char *buf;
++
++ if (mp->pid == -1 || mp->current_pid == -1) {
++ buf = "(none)\n";
++ return simple_read_from_buffer(ubuf, cnt, ppos, buf,
++ strlen(buf));
++ }
++
++ buf = kmalloc(strmaxlen, GFP_KERNEL);
++ if (buf == NULL)
++ return -ENOMEM;
++
++ t = ns2usecs(mp->timestamp);
++ usecs = do_div(t, USEC_PER_SEC);
++ secs = (unsigned long) t;
++ r = snprintf(buf, strmaxlen,
++ "%d %d %ld (%ld) %s <- %d %d %s %lu.%06lu\n", mp->pid,
++ MAX_RT_PRIO-1 - mp->prio, mp->latency, mp->timeroffset, mp->comm,
++ mp->current_pid, MAX_RT_PRIO-1 - mp->current_prio, mp->current_comm,
++ secs, usecs);
++ r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
++ kfree(buf);
++ return r;
++}
++#endif
++
++static ssize_t
++show_enable(struct file *file, char __user *ubuf, size_t cnt, loff_t *ppos)
++{
++ char buf[64];
++ struct enable_data *ed = file->private_data;
++ int r;
++
++ r = snprintf(buf, sizeof(buf), "%d\n", ed->enabled);
++ return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
++}
++
++static ssize_t
++do_enable(struct file *file, const char __user *ubuf, size_t cnt, loff_t *ppos)
++{
++ char buf[64];
++ long enable;
++ struct enable_data *ed = file->private_data;
++
++ if (cnt >= sizeof(buf))
++ return -EINVAL;
++
++ if (copy_from_user(&buf, ubuf, cnt))
++ return -EFAULT;
++
++ buf[cnt] = 0;
++
++ if (kstrtoul(buf, 10, &enable))
++ return -EINVAL;
++
++ if ((enable && ed->enabled) || (!enable && !ed->enabled))
++ return cnt;
++
++ if (enable) {
++ int ret;
++
++ switch (ed->latency_type) {
++#if defined(CONFIG_INTERRUPT_OFF_HIST) || defined(CONFIG_PREEMPT_OFF_HIST)
++ case PREEMPTIRQSOFF_LATENCY:
++ ret = register_trace_preemptirqsoff_hist(
++ probe_preemptirqsoff_hist, NULL);
++ if (ret) {
++ pr_info("wakeup trace: Couldn't assign "
++ "probe_preemptirqsoff_hist "
++ "to trace_preemptirqsoff_hist\n");
++ return ret;
++ }
++ break;
++#endif
++#ifdef CONFIG_WAKEUP_LATENCY_HIST
++ case WAKEUP_LATENCY:
++ ret = register_trace_sched_wakeup(
++ probe_wakeup_latency_hist_start, NULL);
++ if (ret) {
++ pr_info("wakeup trace: Couldn't assign "
++ "probe_wakeup_latency_hist_start "
++ "to trace_sched_wakeup\n");
++ return ret;
++ }
++ ret = register_trace_sched_wakeup_new(
++ probe_wakeup_latency_hist_start, NULL);
++ if (ret) {
++ pr_info("wakeup trace: Couldn't assign "
++ "probe_wakeup_latency_hist_start "
++ "to trace_sched_wakeup_new\n");
++ unregister_trace_sched_wakeup(
++ probe_wakeup_latency_hist_start, NULL);
++ return ret;
++ }
++ ret = register_trace_sched_switch(
++ probe_wakeup_latency_hist_stop, NULL);
++ if (ret) {
++ pr_info("wakeup trace: Couldn't assign "
++ "probe_wakeup_latency_hist_stop "
++ "to trace_sched_switch\n");
++ unregister_trace_sched_wakeup(
++ probe_wakeup_latency_hist_start, NULL);
++ unregister_trace_sched_wakeup_new(
++ probe_wakeup_latency_hist_start, NULL);
++ return ret;
++ }
++ ret = register_trace_sched_migrate_task(
++ probe_sched_migrate_task, NULL);
++ if (ret) {
++ pr_info("wakeup trace: Couldn't assign "
++ "probe_sched_migrate_task "
++ "to trace_sched_migrate_task\n");
++ unregister_trace_sched_wakeup(
++ probe_wakeup_latency_hist_start, NULL);
++ unregister_trace_sched_wakeup_new(
++ probe_wakeup_latency_hist_start, NULL);
++ unregister_trace_sched_switch(
++ probe_wakeup_latency_hist_stop, NULL);
++ return ret;
++ }
++ break;
++#endif
++#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST
++ case MISSED_TIMER_OFFSETS:
++ ret = register_trace_hrtimer_interrupt(
++ probe_hrtimer_interrupt, NULL);
++ if (ret) {
++ pr_info("wakeup trace: Couldn't assign "
++ "probe_hrtimer_interrupt "
++ "to trace_hrtimer_interrupt\n");
++ return ret;
++ }
++ break;
++#endif
++#if defined(CONFIG_WAKEUP_LATENCY_HIST) && \
++ defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
++ case TIMERANDWAKEUP_LATENCY:
++ if (!wakeup_latency_enabled_data.enabled ||
++ !missed_timer_offsets_enabled_data.enabled)
++ return -EINVAL;
++ break;
++#endif
++ default:
++ break;
++ }
++ } else {
++ switch (ed->latency_type) {
++#if defined(CONFIG_INTERRUPT_OFF_HIST) || defined(CONFIG_PREEMPT_OFF_HIST)
++ case PREEMPTIRQSOFF_LATENCY:
++ {
++ int cpu;
++
++ unregister_trace_preemptirqsoff_hist(
++ probe_preemptirqsoff_hist, NULL);
++ for_each_online_cpu(cpu) {
++#ifdef CONFIG_INTERRUPT_OFF_HIST
++ per_cpu(hist_irqsoff_counting,
++ cpu) = 0;
++#endif
++#ifdef CONFIG_PREEMPT_OFF_HIST
++ per_cpu(hist_preemptoff_counting,
++ cpu) = 0;
++#endif
++#if defined(CONFIG_INTERRUPT_OFF_HIST) && defined(CONFIG_PREEMPT_OFF_HIST)
++ per_cpu(hist_preemptirqsoff_counting,
++ cpu) = 0;
++#endif
++ }
++ }
++ break;
++#endif
++#ifdef CONFIG_WAKEUP_LATENCY_HIST
++ case WAKEUP_LATENCY:
++ {
++ int cpu;
++
++ unregister_trace_sched_wakeup(
++ probe_wakeup_latency_hist_start, NULL);
++ unregister_trace_sched_wakeup_new(
++ probe_wakeup_latency_hist_start, NULL);
++ unregister_trace_sched_switch(
++ probe_wakeup_latency_hist_stop, NULL);
++ unregister_trace_sched_migrate_task(
++ probe_sched_migrate_task, NULL);
++
++ for_each_online_cpu(cpu) {
++ per_cpu(wakeup_task, cpu) = NULL;
++ per_cpu(wakeup_sharedprio, cpu) = 0;
++ }
++ }
++#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST
++ timerandwakeup_enabled_data.enabled = 0;
++#endif
++ break;
++#endif
++#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST
++ case MISSED_TIMER_OFFSETS:
++ unregister_trace_hrtimer_interrupt(
++ probe_hrtimer_interrupt, NULL);
++#ifdef CONFIG_WAKEUP_LATENCY_HIST
++ timerandwakeup_enabled_data.enabled = 0;
++#endif
++ break;
++#endif
++ default:
++ break;
++ }
++ }
++ ed->enabled = enable;
++ return cnt;
++}
++
++static const struct file_operations latency_hist_reset_fops = {
++ .open = tracing_open_generic,
++ .write = latency_hist_reset,
++};
++
++static const struct file_operations enable_fops = {
++ .open = tracing_open_generic,
++ .read = show_enable,
++ .write = do_enable,
++};
++
++#if defined(CONFIG_WAKEUP_LATENCY_HIST) || \
++ defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
++static const struct file_operations pid_fops = {
++ .open = tracing_open_generic,
++ .read = show_pid,
++ .write = do_pid,
++};
++
++static const struct file_operations maxlatproc_fops = {
++ .open = tracing_open_generic,
++ .read = show_maxlatproc,
++};
++#endif
++
++#if defined(CONFIG_INTERRUPT_OFF_HIST) || defined(CONFIG_PREEMPT_OFF_HIST)
++static notrace void probe_preemptirqsoff_hist(void *v, int reason,
++ int starthist)
++{
++ int cpu = raw_smp_processor_id();
++ int time_set = 0;
++
++ if (starthist) {
++ cycle_t uninitialized_var(start);
++
++ if (!preempt_count() && !irqs_disabled())
++ return;
++
++#ifdef CONFIG_INTERRUPT_OFF_HIST
++ if ((reason == IRQS_OFF || reason == TRACE_START) &&
++ !per_cpu(hist_irqsoff_counting, cpu)) {
++ per_cpu(hist_irqsoff_counting, cpu) = 1;
++ start = ftrace_now(cpu);
++ time_set++;
++ per_cpu(hist_irqsoff_start, cpu) = start;
++ }
++#endif
++
++#ifdef CONFIG_PREEMPT_OFF_HIST
++ if ((reason == PREEMPT_OFF || reason == TRACE_START) &&
++ !per_cpu(hist_preemptoff_counting, cpu)) {
++ per_cpu(hist_preemptoff_counting, cpu) = 1;
++ if (!(time_set++))
++ start = ftrace_now(cpu);
++ per_cpu(hist_preemptoff_start, cpu) = start;
++ }
++#endif
++
++#if defined(CONFIG_INTERRUPT_OFF_HIST) && defined(CONFIG_PREEMPT_OFF_HIST)
++ if (per_cpu(hist_irqsoff_counting, cpu) &&
++ per_cpu(hist_preemptoff_counting, cpu) &&
++ !per_cpu(hist_preemptirqsoff_counting, cpu)) {
++ per_cpu(hist_preemptirqsoff_counting, cpu) = 1;
++ if (!time_set)
++ start = ftrace_now(cpu);
++ per_cpu(hist_preemptirqsoff_start, cpu) = start;
++ }
++#endif
++ } else {
++ cycle_t uninitialized_var(stop);
++
++#ifdef CONFIG_INTERRUPT_OFF_HIST
++ if ((reason == IRQS_ON || reason == TRACE_STOP) &&
++ per_cpu(hist_irqsoff_counting, cpu)) {
++ cycle_t start = per_cpu(hist_irqsoff_start, cpu);
++
++ stop = ftrace_now(cpu);
++ time_set++;
++ if (start) {
++ long latency = ((long) (stop - start)) /
++ NSECS_PER_USECS;
++
++ latency_hist(IRQSOFF_LATENCY, cpu, latency, 0,
++ stop, NULL);
++ }
++ per_cpu(hist_irqsoff_counting, cpu) = 0;
++ }
++#endif
++
++#ifdef CONFIG_PREEMPT_OFF_HIST
++ if ((reason == PREEMPT_ON || reason == TRACE_STOP) &&
++ per_cpu(hist_preemptoff_counting, cpu)) {
++ cycle_t start = per_cpu(hist_preemptoff_start, cpu);
++
++ if (!(time_set++))
++ stop = ftrace_now(cpu);
++ if (start) {
++ long latency = ((long) (stop - start)) /
++ NSECS_PER_USECS;
++
++ latency_hist(PREEMPTOFF_LATENCY, cpu, latency,
++ 0, stop, NULL);
++ }
++ per_cpu(hist_preemptoff_counting, cpu) = 0;
++ }
++#endif
++
++#if defined(CONFIG_INTERRUPT_OFF_HIST) && defined(CONFIG_PREEMPT_OFF_HIST)
++ if ((!per_cpu(hist_irqsoff_counting, cpu) ||
++ !per_cpu(hist_preemptoff_counting, cpu)) &&
++ per_cpu(hist_preemptirqsoff_counting, cpu)) {
++ cycle_t start = per_cpu(hist_preemptirqsoff_start, cpu);
++
++ if (!time_set)
++ stop = ftrace_now(cpu);
++ if (start) {
++ long latency = ((long) (stop - start)) /
++ NSECS_PER_USECS;
++
++ latency_hist(PREEMPTIRQSOFF_LATENCY, cpu,
++ latency, 0, stop, NULL);
++ }
++ per_cpu(hist_preemptirqsoff_counting, cpu) = 0;
++ }
++#endif
++ }
++}
++#endif
++
++#ifdef CONFIG_WAKEUP_LATENCY_HIST
++static DEFINE_RAW_SPINLOCK(wakeup_lock);
++static notrace void probe_sched_migrate_task(void *v, struct task_struct *task,
++ int cpu)
++{
++ int old_cpu = task_cpu(task);
++
++ if (cpu != old_cpu) {
++ unsigned long flags;
++ struct task_struct *cpu_wakeup_task;
++
++ raw_spin_lock_irqsave(&wakeup_lock, flags);
++
++ cpu_wakeup_task = per_cpu(wakeup_task, old_cpu);
++ if (task == cpu_wakeup_task) {
++ put_task_struct(cpu_wakeup_task);
++ per_cpu(wakeup_task, old_cpu) = NULL;
++ cpu_wakeup_task = per_cpu(wakeup_task, cpu) = task;
++ get_task_struct(cpu_wakeup_task);
++ }
++
++ raw_spin_unlock_irqrestore(&wakeup_lock, flags);
++ }
++}
++
++static notrace void probe_wakeup_latency_hist_start(void *v,
++ struct task_struct *p)
++{
++ unsigned long flags;
++ struct task_struct *curr = current;
++ int cpu = task_cpu(p);
++ struct task_struct *cpu_wakeup_task;
++
++ raw_spin_lock_irqsave(&wakeup_lock, flags);
++
++ cpu_wakeup_task = per_cpu(wakeup_task, cpu);
++
++ if (wakeup_pid) {
++ if ((cpu_wakeup_task && p->prio == cpu_wakeup_task->prio) ||
++ p->prio == curr->prio)
++ per_cpu(wakeup_sharedprio, cpu) = 1;
++ if (likely(wakeup_pid != task_pid_nr(p)))
++ goto out;
++ } else {
++ if (likely(!rt_task(p)) ||
++ (cpu_wakeup_task && p->prio > cpu_wakeup_task->prio) ||
++ p->prio > curr->prio)
++ goto out;
++ if ((cpu_wakeup_task && p->prio == cpu_wakeup_task->prio) ||
++ p->prio == curr->prio)
++ per_cpu(wakeup_sharedprio, cpu) = 1;
++ }
++
++ if (cpu_wakeup_task)
++ put_task_struct(cpu_wakeup_task);
++ cpu_wakeup_task = per_cpu(wakeup_task, cpu) = p;
++ get_task_struct(cpu_wakeup_task);
++ cpu_wakeup_task->preempt_timestamp_hist =
++ ftrace_now(raw_smp_processor_id());
++out:
++ raw_spin_unlock_irqrestore(&wakeup_lock, flags);
++}
++
++static notrace void probe_wakeup_latency_hist_stop(void *v,
++ bool preempt, struct task_struct *prev, struct task_struct *next)
++{
++ unsigned long flags;
++ int cpu = task_cpu(next);
++ long latency;
++ cycle_t stop;
++ struct task_struct *cpu_wakeup_task;
++
++ raw_spin_lock_irqsave(&wakeup_lock, flags);
++
++ cpu_wakeup_task = per_cpu(wakeup_task, cpu);
++
++ if (cpu_wakeup_task == NULL)
++ goto out;
++
++ /* Already running? */
++ if (unlikely(current == cpu_wakeup_task))
++ goto out_reset;
++
++ if (next != cpu_wakeup_task) {
++ if (next->prio < cpu_wakeup_task->prio)
++ goto out_reset;
++
++ if (next->prio == cpu_wakeup_task->prio)
++ per_cpu(wakeup_sharedprio, cpu) = 1;
++
++ goto out;
++ }
++
++ if (current->prio == cpu_wakeup_task->prio)
++ per_cpu(wakeup_sharedprio, cpu) = 1;
++
++ /*
++ * The task we are waiting for is about to be switched to.
++ * Calculate latency and store it in histogram.
++ */
++ stop = ftrace_now(raw_smp_processor_id());
++
++ latency = ((long) (stop - next->preempt_timestamp_hist)) /
++ NSECS_PER_USECS;
++
++ if (per_cpu(wakeup_sharedprio, cpu)) {
++ latency_hist(WAKEUP_LATENCY_SHAREDPRIO, cpu, latency, 0, stop,
++ next);
++ per_cpu(wakeup_sharedprio, cpu) = 0;
++ } else {
++ latency_hist(WAKEUP_LATENCY, cpu, latency, 0, stop, next);
++#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST
++ if (timerandwakeup_enabled_data.enabled) {
++ latency_hist(TIMERANDWAKEUP_LATENCY, cpu,
++ next->timer_offset + latency, next->timer_offset,
++ stop, next);
++ }
++#endif
++ }
++
++out_reset:
++#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST
++ next->timer_offset = 0;
++#endif
++ put_task_struct(cpu_wakeup_task);
++ per_cpu(wakeup_task, cpu) = NULL;
++out:
++ raw_spin_unlock_irqrestore(&wakeup_lock, flags);
++}
++#endif
++
++#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST
++static notrace void probe_hrtimer_interrupt(void *v, int cpu,
++ long long latency_ns, struct task_struct *curr,
++ struct task_struct *task)
++{
++ if (latency_ns <= 0 && task != NULL && rt_task(task) &&
++ (task->prio < curr->prio ||
++ (task->prio == curr->prio &&
++ !cpumask_test_cpu(cpu, &task->cpus_allowed)))) {
++ long latency;
++ cycle_t now;
++
++ if (missed_timer_offsets_pid) {
++ if (likely(missed_timer_offsets_pid !=
++ task_pid_nr(task)))
++ return;
++ }
++
++ now = ftrace_now(cpu);
++ latency = (long) div_s64(-latency_ns, NSECS_PER_USECS);
++ latency_hist(MISSED_TIMER_OFFSETS, cpu, latency, latency, now,
++ task);
++#ifdef CONFIG_WAKEUP_LATENCY_HIST
++ task->timer_offset = latency;
++#endif
++ }
++}
++#endif
++
++static __init int latency_hist_init(void)
++{
++ struct dentry *latency_hist_root = NULL;
++ struct dentry *dentry;
++#ifdef CONFIG_WAKEUP_LATENCY_HIST
++ struct dentry *dentry_sharedprio;
++#endif
++ struct dentry *entry;
++ struct dentry *enable_root;
++ int i = 0;
++ struct hist_data *my_hist;
++ char name[64];
++ char *cpufmt = "CPU%d";
++#if defined(CONFIG_WAKEUP_LATENCY_HIST) || \
++ defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
++ char *cpufmt_maxlatproc = "max_latency-CPU%d";
++ struct maxlatproc_data *mp = NULL;
++#endif
++
++ dentry = tracing_init_dentry();
++ latency_hist_root = debugfs_create_dir(latency_hist_dir_root, dentry);
++ enable_root = debugfs_create_dir("enable", latency_hist_root);
++
++#ifdef CONFIG_INTERRUPT_OFF_HIST
++ dentry = debugfs_create_dir(irqsoff_hist_dir, latency_hist_root);
++ for_each_possible_cpu(i) {
++ sprintf(name, cpufmt, i);
++ entry = debugfs_create_file(name, 0444, dentry,
++ &per_cpu(irqsoff_hist, i), &latency_hist_fops);
++ my_hist = &per_cpu(irqsoff_hist, i);
++ atomic_set(&my_hist->hist_mode, 1);
++ my_hist->min_lat = LONG_MAX;
++ }
++ entry = debugfs_create_file("reset", 0644, dentry,
++ (void *)IRQSOFF_LATENCY, &latency_hist_reset_fops);
++#endif
++
++#ifdef CONFIG_PREEMPT_OFF_HIST
++ dentry = debugfs_create_dir(preemptoff_hist_dir,
++ latency_hist_root);
++ for_each_possible_cpu(i) {
++ sprintf(name, cpufmt, i);
++ entry = debugfs_create_file(name, 0444, dentry,
++ &per_cpu(preemptoff_hist, i), &latency_hist_fops);
++ my_hist = &per_cpu(preemptoff_hist, i);
++ atomic_set(&my_hist->hist_mode, 1);
++ my_hist->min_lat = LONG_MAX;
++ }
++ entry = debugfs_create_file("reset", 0644, dentry,
++ (void *)PREEMPTOFF_LATENCY, &latency_hist_reset_fops);
++#endif
++
++#if defined(CONFIG_INTERRUPT_OFF_HIST) && defined(CONFIG_PREEMPT_OFF_HIST)
++ dentry = debugfs_create_dir(preemptirqsoff_hist_dir,
++ latency_hist_root);
++ for_each_possible_cpu(i) {
++ sprintf(name, cpufmt, i);
++ entry = debugfs_create_file(name, 0444, dentry,
++ &per_cpu(preemptirqsoff_hist, i), &latency_hist_fops);
++ my_hist = &per_cpu(preemptirqsoff_hist, i);
++ atomic_set(&my_hist->hist_mode, 1);
++ my_hist->min_lat = LONG_MAX;
++ }
++ entry = debugfs_create_file("reset", 0644, dentry,
++ (void *)PREEMPTIRQSOFF_LATENCY, &latency_hist_reset_fops);
++#endif
++
++#if defined(CONFIG_INTERRUPT_OFF_HIST) || defined(CONFIG_PREEMPT_OFF_HIST)
++ entry = debugfs_create_file("preemptirqsoff", 0644,
++ enable_root, (void *)&preemptirqsoff_enabled_data,
++ &enable_fops);
++#endif
++
++#ifdef CONFIG_WAKEUP_LATENCY_HIST
++ dentry = debugfs_create_dir(wakeup_latency_hist_dir,
++ latency_hist_root);
++ dentry_sharedprio = debugfs_create_dir(
++ wakeup_latency_hist_dir_sharedprio, dentry);
++ for_each_possible_cpu(i) {
++ sprintf(name, cpufmt, i);
++
++ entry = debugfs_create_file(name, 0444, dentry,
++ &per_cpu(wakeup_latency_hist, i),
++ &latency_hist_fops);
++ my_hist = &per_cpu(wakeup_latency_hist, i);
++ atomic_set(&my_hist->hist_mode, 1);
++ my_hist->min_lat = LONG_MAX;
++
++ entry = debugfs_create_file(name, 0444, dentry_sharedprio,
++ &per_cpu(wakeup_latency_hist_sharedprio, i),
++ &latency_hist_fops);
++ my_hist = &per_cpu(wakeup_latency_hist_sharedprio, i);
++ atomic_set(&my_hist->hist_mode, 1);
++ my_hist->min_lat = LONG_MAX;
++
++ sprintf(name, cpufmt_maxlatproc, i);
++
++ mp = &per_cpu(wakeup_maxlatproc, i);
++ entry = debugfs_create_file(name, 0444, dentry, mp,
++ &maxlatproc_fops);
++ clear_maxlatprocdata(mp);
++
++ mp = &per_cpu(wakeup_maxlatproc_sharedprio, i);
++ entry = debugfs_create_file(name, 0444, dentry_sharedprio, mp,
++ &maxlatproc_fops);
++ clear_maxlatprocdata(mp);
++ }
++ entry = debugfs_create_file("pid", 0644, dentry,
++ (void *)&wakeup_pid, &pid_fops);
++ entry = debugfs_create_file("reset", 0644, dentry,
++ (void *)WAKEUP_LATENCY, &latency_hist_reset_fops);
++ entry = debugfs_create_file("reset", 0644, dentry_sharedprio,
++ (void *)WAKEUP_LATENCY_SHAREDPRIO, &latency_hist_reset_fops);
++ entry = debugfs_create_file("wakeup", 0644,
++ enable_root, (void *)&wakeup_latency_enabled_data,
++ &enable_fops);
++#endif
++
++#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST
++ dentry = debugfs_create_dir(missed_timer_offsets_dir,
++ latency_hist_root);
++ for_each_possible_cpu(i) {
++ sprintf(name, cpufmt, i);
++ entry = debugfs_create_file(name, 0444, dentry,
++ &per_cpu(missed_timer_offsets, i), &latency_hist_fops);
++ my_hist = &per_cpu(missed_timer_offsets, i);
++ atomic_set(&my_hist->hist_mode, 1);
++ my_hist->min_lat = LONG_MAX;
++
++ sprintf(name, cpufmt_maxlatproc, i);
++ mp = &per_cpu(missed_timer_offsets_maxlatproc, i);
++ entry = debugfs_create_file(name, 0444, dentry, mp,
++ &maxlatproc_fops);
++ clear_maxlatprocdata(mp);
++ }
++ entry = debugfs_create_file("pid", 0644, dentry,
++ (void *)&missed_timer_offsets_pid, &pid_fops);
++ entry = debugfs_create_file("reset", 0644, dentry,
++ (void *)MISSED_TIMER_OFFSETS, &latency_hist_reset_fops);
++ entry = debugfs_create_file("missed_timer_offsets", 0644,
++ enable_root, (void *)&missed_timer_offsets_enabled_data,
++ &enable_fops);
++#endif
++
++#if defined(CONFIG_WAKEUP_LATENCY_HIST) && \
++ defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
++ dentry = debugfs_create_dir(timerandwakeup_latency_hist_dir,
++ latency_hist_root);
++ for_each_possible_cpu(i) {
++ sprintf(name, cpufmt, i);
++ entry = debugfs_create_file(name, 0444, dentry,
++ &per_cpu(timerandwakeup_latency_hist, i),
++ &latency_hist_fops);
++ my_hist = &per_cpu(timerandwakeup_latency_hist, i);
++ atomic_set(&my_hist->hist_mode, 1);
++ my_hist->min_lat = LONG_MAX;
++
++ sprintf(name, cpufmt_maxlatproc, i);
++ mp = &per_cpu(timerandwakeup_maxlatproc, i);
++ entry = debugfs_create_file(name, 0444, dentry, mp,
++ &maxlatproc_fops);
++ clear_maxlatprocdata(mp);
++ }
++ entry = debugfs_create_file("reset", 0644, dentry,
++ (void *)TIMERANDWAKEUP_LATENCY, &latency_hist_reset_fops);
++ entry = debugfs_create_file("timerandwakeup", 0644,
++ enable_root, (void *)&timerandwakeup_enabled_data,
++ &enable_fops);
++#endif
++ return 0;
++}
++
++device_initcall(latency_hist_init);
+diff -Nur linux-4.8.15.orig/kernel/trace/Makefile linux-4.8.15/kernel/trace/Makefile
+--- linux-4.8.15.orig/kernel/trace/Makefile 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/trace/Makefile 2017-01-01 17:07:16.051428246 +0100
+@@ -37,6 +37,10 @@
+ obj-$(CONFIG_IRQSOFF_TRACER) += trace_irqsoff.o
+ obj-$(CONFIG_PREEMPT_TRACER) += trace_irqsoff.o
+ obj-$(CONFIG_SCHED_TRACER) += trace_sched_wakeup.o
++obj-$(CONFIG_INTERRUPT_OFF_HIST) += latency_hist.o
++obj-$(CONFIG_PREEMPT_OFF_HIST) += latency_hist.o
++obj-$(CONFIG_WAKEUP_LATENCY_HIST) += latency_hist.o
++obj-$(CONFIG_MISSED_TIMER_OFFSETS_HIST) += latency_hist.o
+ obj-$(CONFIG_NOP_TRACER) += trace_nop.o
+ obj-$(CONFIG_STACK_TRACER) += trace_stack.o
+ obj-$(CONFIG_MMIOTRACE) += trace_mmiotrace.o
+diff -Nur linux-4.8.15.orig/kernel/trace/trace.c linux-4.8.15/kernel/trace/trace.c
+--- linux-4.8.15.orig/kernel/trace/trace.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/trace/trace.c 2017-01-01 17:07:16.055428503 +0100
+@@ -1897,6 +1897,7 @@
+ struct task_struct *tsk = current;
+
+ entry->preempt_count = pc & 0xff;
++ entry->preempt_lazy_count = preempt_lazy_count();
+ entry->pid = (tsk) ? tsk->pid : 0;
+ entry->flags =
+ #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
+@@ -1907,8 +1908,11 @@
+ ((pc & NMI_MASK ) ? TRACE_FLAG_NMI : 0) |
+ ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) |
+ ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) |
+- (tif_need_resched() ? TRACE_FLAG_NEED_RESCHED : 0) |
++ (tif_need_resched_now() ? TRACE_FLAG_NEED_RESCHED : 0) |
++ (need_resched_lazy() ? TRACE_FLAG_NEED_RESCHED_LAZY : 0) |
+ (test_preempt_need_resched() ? TRACE_FLAG_PREEMPT_RESCHED : 0);
++
++ entry->migrate_disable = (tsk) ? __migrate_disabled(tsk) & 0xFF : 0;
+ }
+ EXPORT_SYMBOL_GPL(tracing_generic_entry_update);
+
+@@ -2892,14 +2896,17 @@
+
+ static void print_lat_help_header(struct seq_file *m)
+ {
+- seq_puts(m, "# _------=> CPU# \n"
+- "# / _-----=> irqs-off \n"
+- "# | / _----=> need-resched \n"
+- "# || / _---=> hardirq/softirq \n"
+- "# ||| / _--=> preempt-depth \n"
+- "# |||| / delay \n"
+- "# cmd pid ||||| time | caller \n"
+- "# \\ / ||||| \\ | / \n");
++ seq_puts(m, "# _--------=> CPU# \n"
++ "# / _-------=> irqs-off \n"
++ "# | / _------=> need-resched \n"
++ "# || / _-----=> need-resched_lazy \n"
++ "# ||| / _----=> hardirq/softirq \n"
++ "# |||| / _---=> preempt-depth \n"
++ "# ||||| / _--=> preempt-lazy-depth\n"
++ "# |||||| / _-=> migrate-disable \n"
++ "# ||||||| / delay \n"
++ "# cmd pid |||||||| time | caller \n"
++ "# \\ / |||||||| \\ | / \n");
+ }
+
+ static void print_event_info(struct trace_buffer *buf, struct seq_file *m)
+@@ -2925,11 +2932,14 @@
+ print_event_info(buf, m);
+ seq_puts(m, "# _-----=> irqs-off\n"
+ "# / _----=> need-resched\n"
+- "# | / _---=> hardirq/softirq\n"
+- "# || / _--=> preempt-depth\n"
+- "# ||| / delay\n"
+- "# TASK-PID CPU# |||| TIMESTAMP FUNCTION\n"
+- "# | | | |||| | |\n");
++ "# |/ _-----=> need-resched_lazy\n"
++ "# || / _---=> hardirq/softirq\n"
++ "# ||| / _--=> preempt-depth\n"
++ "# |||| / _-=> preempt-lazy-depth\n"
++ "# ||||| / _-=> migrate-disable \n"
++ "# |||||| / delay\n"
++ "# TASK-PID CPU# ||||||| TIMESTAMP FUNCTION\n"
++ "# | | | ||||||| | |\n");
+ }
+
+ void
+diff -Nur linux-4.8.15.orig/kernel/trace/trace_events.c linux-4.8.15/kernel/trace/trace_events.c
+--- linux-4.8.15.orig/kernel/trace/trace_events.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/trace/trace_events.c 2017-01-01 17:07:16.059428767 +0100
+@@ -187,6 +187,8 @@
+ __common_field(unsigned char, flags);
+ __common_field(unsigned char, preempt_count);
+ __common_field(int, pid);
++ __common_field(unsigned short, migrate_disable);
++ __common_field(unsigned short, padding);
+
+ return ret;
+ }
+diff -Nur linux-4.8.15.orig/kernel/trace/trace.h linux-4.8.15/kernel/trace/trace.h
+--- linux-4.8.15.orig/kernel/trace/trace.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/trace/trace.h 2017-01-01 17:07:16.055428503 +0100
+@@ -123,6 +123,7 @@
+ * NEED_RESCHED - reschedule is requested
+ * HARDIRQ - inside an interrupt handler
+ * SOFTIRQ - inside a softirq handler
++ * NEED_RESCHED_LAZY - lazy reschedule is requested
+ */
+ enum trace_flag_type {
+ TRACE_FLAG_IRQS_OFF = 0x01,
+@@ -132,6 +133,7 @@
+ TRACE_FLAG_SOFTIRQ = 0x10,
+ TRACE_FLAG_PREEMPT_RESCHED = 0x20,
+ TRACE_FLAG_NMI = 0x40,
++ TRACE_FLAG_NEED_RESCHED_LAZY = 0x80,
+ };
+
+ #define TRACE_BUF_SIZE 1024
+diff -Nur linux-4.8.15.orig/kernel/trace/trace_irqsoff.c linux-4.8.15/kernel/trace/trace_irqsoff.c
+--- linux-4.8.15.orig/kernel/trace/trace_irqsoff.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/trace/trace_irqsoff.c 2017-01-01 17:07:16.059428767 +0100
+@@ -13,6 +13,7 @@
+ #include <linux/uaccess.h>
+ #include <linux/module.h>
+ #include <linux/ftrace.h>
++#include <trace/events/hist.h>
+
+ #include "trace.h"
+
+@@ -424,11 +425,13 @@
+ {
+ if (preempt_trace() || irq_trace())
+ start_critical_timing(CALLER_ADDR0, CALLER_ADDR1);
++ trace_preemptirqsoff_hist_rcuidle(TRACE_START, 1);
+ }
+ EXPORT_SYMBOL_GPL(start_critical_timings);
+
+ void stop_critical_timings(void)
+ {
++ trace_preemptirqsoff_hist_rcuidle(TRACE_STOP, 0);
+ if (preempt_trace() || irq_trace())
+ stop_critical_timing(CALLER_ADDR0, CALLER_ADDR1);
+ }
+@@ -438,6 +441,7 @@
+ #ifdef CONFIG_PROVE_LOCKING
+ void time_hardirqs_on(unsigned long a0, unsigned long a1)
+ {
++ trace_preemptirqsoff_hist_rcuidle(IRQS_ON, 0);
+ if (!preempt_trace() && irq_trace())
+ stop_critical_timing(a0, a1);
+ }
+@@ -446,6 +450,7 @@
+ {
+ if (!preempt_trace() && irq_trace())
+ start_critical_timing(a0, a1);
++ trace_preemptirqsoff_hist_rcuidle(IRQS_OFF, 1);
+ }
+
+ #else /* !CONFIG_PROVE_LOCKING */
+@@ -471,6 +476,7 @@
+ */
+ void trace_hardirqs_on(void)
+ {
++ trace_preemptirqsoff_hist(IRQS_ON, 0);
+ if (!preempt_trace() && irq_trace())
+ stop_critical_timing(CALLER_ADDR0, CALLER_ADDR1);
+ }
+@@ -480,11 +486,13 @@
+ {
+ if (!preempt_trace() && irq_trace())
+ start_critical_timing(CALLER_ADDR0, CALLER_ADDR1);
++ trace_preemptirqsoff_hist(IRQS_OFF, 1);
+ }
+ EXPORT_SYMBOL(trace_hardirqs_off);
+
+ __visible void trace_hardirqs_on_caller(unsigned long caller_addr)
+ {
++ trace_preemptirqsoff_hist(IRQS_ON, 0);
+ if (!preempt_trace() && irq_trace())
+ stop_critical_timing(CALLER_ADDR0, caller_addr);
+ }
+@@ -494,6 +502,7 @@
+ {
+ if (!preempt_trace() && irq_trace())
+ start_critical_timing(CALLER_ADDR0, caller_addr);
++ trace_preemptirqsoff_hist(IRQS_OFF, 1);
+ }
+ EXPORT_SYMBOL(trace_hardirqs_off_caller);
+
+@@ -503,12 +512,14 @@
+ #ifdef CONFIG_PREEMPT_TRACER
+ void trace_preempt_on(unsigned long a0, unsigned long a1)
+ {
++ trace_preemptirqsoff_hist(PREEMPT_ON, 0);
+ if (preempt_trace() && !irq_trace())
+ stop_critical_timing(a0, a1);
+ }
+
+ void trace_preempt_off(unsigned long a0, unsigned long a1)
+ {
++ trace_preemptirqsoff_hist(PREEMPT_ON, 1);
+ if (preempt_trace() && !irq_trace())
+ start_critical_timing(a0, a1);
+ }
+diff -Nur linux-4.8.15.orig/kernel/trace/trace_output.c linux-4.8.15/kernel/trace/trace_output.c
+--- linux-4.8.15.orig/kernel/trace/trace_output.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/trace/trace_output.c 2017-01-01 17:07:16.059428767 +0100
+@@ -386,6 +386,7 @@
+ {
+ char hardsoft_irq;
+ char need_resched;
++ char need_resched_lazy;
+ char irqs_off;
+ int hardirq;
+ int softirq;
+@@ -416,6 +417,9 @@
+ break;
+ }
+
++ need_resched_lazy =
++ (entry->flags & TRACE_FLAG_NEED_RESCHED_LAZY) ? 'L' : '.';
++
+ hardsoft_irq =
+ (nmi && hardirq) ? 'Z' :
+ nmi ? 'z' :
+@@ -424,14 +428,25 @@
+ softirq ? 's' :
+ '.' ;
+
+- trace_seq_printf(s, "%c%c%c",
+- irqs_off, need_resched, hardsoft_irq);
++ trace_seq_printf(s, "%c%c%c%c",
++ irqs_off, need_resched, need_resched_lazy,
++ hardsoft_irq);
+
+ if (entry->preempt_count)
+ trace_seq_printf(s, "%x", entry->preempt_count);
+ else
+ trace_seq_putc(s, '.');
+
++ if (entry->preempt_lazy_count)
++ trace_seq_printf(s, "%x", entry->preempt_lazy_count);
++ else
++ trace_seq_putc(s, '.');
++
++ if (entry->migrate_disable)
++ trace_seq_printf(s, "%x", entry->migrate_disable);
++ else
++ trace_seq_putc(s, '.');
++
+ return !trace_seq_has_overflowed(s);
+ }
+
+diff -Nur linux-4.8.15.orig/kernel/user.c linux-4.8.15/kernel/user.c
+--- linux-4.8.15.orig/kernel/user.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/user.c 2017-01-01 17:07:16.059428767 +0100
+@@ -161,11 +161,11 @@
+ if (!up)
+ return;
+
+- local_irq_save(flags);
++ local_irq_save_nort(flags);
+ if (atomic_dec_and_lock(&up->__count, &uidhash_lock))
+ free_user(up, flags);
+ else
+- local_irq_restore(flags);
++ local_irq_restore_nort(flags);
+ }
+
+ struct user_struct *alloc_uid(kuid_t uid)
+diff -Nur linux-4.8.15.orig/kernel/watchdog.c linux-4.8.15/kernel/watchdog.c
+--- linux-4.8.15.orig/kernel/watchdog.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/watchdog.c 2017-01-01 17:07:16.059428767 +0100
+@@ -315,6 +315,8 @@
+
+ #ifdef CONFIG_HARDLOCKUP_DETECTOR
+
++static DEFINE_RAW_SPINLOCK(watchdog_output_lock);
++
+ static struct perf_event_attr wd_hw_attr = {
+ .type = PERF_TYPE_HARDWARE,
+ .config = PERF_COUNT_HW_CPU_CYCLES,
+@@ -349,6 +351,13 @@
+ /* only print hardlockups once */
+ if (__this_cpu_read(hard_watchdog_warn) == true)
+ return;
++ /*
++ * If early-printk is enabled then make sure we do not
++ * lock up in printk() and kill console logging:
++ */
++ printk_kill();
++
++ raw_spin_lock(&watchdog_output_lock);
+
+ pr_emerg("Watchdog detected hard LOCKUP on cpu %d", this_cpu);
+ print_modules();
+@@ -366,6 +375,7 @@
+ !test_and_set_bit(0, &hardlockup_allcpu_dumped))
+ trigger_allbutself_cpu_backtrace();
+
++ raw_spin_unlock(&watchdog_output_lock);
+ if (hardlockup_panic)
+ nmi_panic(regs, "Hard LOCKUP");
+
+@@ -513,6 +523,7 @@
+ /* kick off the timer for the hardlockup detector */
+ hrtimer_init(hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+ hrtimer->function = watchdog_timer_fn;
++ hrtimer->irqsafe = 1;
+
+ /* Enable the perf event */
+ watchdog_nmi_enable(cpu);
+diff -Nur linux-4.8.15.orig/kernel/workqueue.c linux-4.8.15/kernel/workqueue.c
+--- linux-4.8.15.orig/kernel/workqueue.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/workqueue.c 2017-01-01 17:07:16.063429015 +0100
+@@ -48,6 +48,8 @@
+ #include <linux/nodemask.h>
+ #include <linux/moduleparam.h>
+ #include <linux/uaccess.h>
++#include <linux/locallock.h>
++#include <linux/delay.h>
+
+ #include "workqueue_internal.h"
+
+@@ -121,11 +123,16 @@
+ * cpu or grabbing pool->lock is enough for read access. If
+ * POOL_DISASSOCIATED is set, it's identical to L.
+ *
++ * On RT we need the extra protection via rt_lock_idle_list() for
++ * the list manipulations against read access from
++ * wq_worker_sleeping(). All other places are nicely serialized via
++ * pool->lock.
++ *
+ * A: pool->attach_mutex protected.
+ *
+ * PL: wq_pool_mutex protected.
+ *
+- * PR: wq_pool_mutex protected for writes. Sched-RCU protected for reads.
++ * PR: wq_pool_mutex protected for writes. RCU protected for reads.
+ *
+ * PW: wq_pool_mutex and wq->mutex protected for writes. Either for reads.
+ *
+@@ -134,7 +141,7 @@
+ *
+ * WQ: wq->mutex protected.
+ *
+- * WR: wq->mutex protected for writes. Sched-RCU protected for reads.
++ * WR: wq->mutex protected for writes. RCU protected for reads.
+ *
+ * MD: wq_mayday_lock protected.
+ */
+@@ -185,7 +192,7 @@
+ atomic_t nr_running ____cacheline_aligned_in_smp;
+
+ /*
+- * Destruction of pool is sched-RCU protected to allow dereferences
++ * Destruction of pool is RCU protected to allow dereferences
+ * from get_work_pool().
+ */
+ struct rcu_head rcu;
+@@ -214,7 +221,7 @@
+ /*
+ * Release of unbound pwq is punted to system_wq. See put_pwq()
+ * and pwq_unbound_release_workfn() for details. pool_workqueue
+- * itself is also sched-RCU protected so that the first pwq can be
++ * itself is also RCU protected so that the first pwq can be
+ * determined without grabbing wq->mutex.
+ */
+ struct work_struct unbound_release_work;
+@@ -348,6 +355,8 @@
+ struct workqueue_struct *system_freezable_power_efficient_wq __read_mostly;
+ EXPORT_SYMBOL_GPL(system_freezable_power_efficient_wq);
+
++static DEFINE_LOCAL_IRQ_LOCK(pendingb_lock);
++
+ static int worker_thread(void *__worker);
+ static void workqueue_sysfs_unregister(struct workqueue_struct *wq);
+
+@@ -355,20 +364,20 @@
+ #include <trace/events/workqueue.h>
+
+ #define assert_rcu_or_pool_mutex() \
+- RCU_LOCKDEP_WARN(!rcu_read_lock_sched_held() && \
++ RCU_LOCKDEP_WARN(!rcu_read_lock_held() && \
+ !lockdep_is_held(&wq_pool_mutex), \
+- "sched RCU or wq_pool_mutex should be held")
++ "RCU or wq_pool_mutex should be held")
+
+ #define assert_rcu_or_wq_mutex(wq) \
+- RCU_LOCKDEP_WARN(!rcu_read_lock_sched_held() && \
++ RCU_LOCKDEP_WARN(!rcu_read_lock_held() && \
+ !lockdep_is_held(&wq->mutex), \
+- "sched RCU or wq->mutex should be held")
++ "RCU or wq->mutex should be held")
+
+ #define assert_rcu_or_wq_mutex_or_pool_mutex(wq) \
+- RCU_LOCKDEP_WARN(!rcu_read_lock_sched_held() && \
++ RCU_LOCKDEP_WARN(!rcu_read_lock_held() && \
+ !lockdep_is_held(&wq->mutex) && \
+ !lockdep_is_held(&wq_pool_mutex), \
+- "sched RCU, wq->mutex or wq_pool_mutex should be held")
++ "RCU, wq->mutex or wq_pool_mutex should be held")
+
+ #define for_each_cpu_worker_pool(pool, cpu) \
+ for ((pool) = &per_cpu(cpu_worker_pools, cpu)[0]; \
+@@ -380,7 +389,7 @@
+ * @pool: iteration cursor
+ * @pi: integer used for iteration
+ *
+- * This must be called either with wq_pool_mutex held or sched RCU read
++ * This must be called either with wq_pool_mutex held or RCU read
+ * locked. If the pool needs to be used beyond the locking in effect, the
+ * caller is responsible for guaranteeing that the pool stays online.
+ *
+@@ -412,7 +421,7 @@
+ * @pwq: iteration cursor
+ * @wq: the target workqueue
+ *
+- * This must be called either with wq->mutex held or sched RCU read locked.
++ * This must be called either with wq->mutex held or RCU read locked.
+ * If the pwq needs to be used beyond the locking in effect, the caller is
+ * responsible for guaranteeing that the pwq stays online.
+ *
+@@ -424,6 +433,31 @@
+ if (({ assert_rcu_or_wq_mutex(wq); false; })) { } \
+ else
+
++#ifdef CONFIG_PREEMPT_RT_BASE
++static inline void rt_lock_idle_list(struct worker_pool *pool)
++{
++ preempt_disable();
++}
++static inline void rt_unlock_idle_list(struct worker_pool *pool)
++{
++ preempt_enable();
++}
++static inline void sched_lock_idle_list(struct worker_pool *pool) { }
++static inline void sched_unlock_idle_list(struct worker_pool *pool) { }
++#else
++static inline void rt_lock_idle_list(struct worker_pool *pool) { }
++static inline void rt_unlock_idle_list(struct worker_pool *pool) { }
++static inline void sched_lock_idle_list(struct worker_pool *pool)
++{
++ spin_lock_irq(&pool->lock);
++}
++static inline void sched_unlock_idle_list(struct worker_pool *pool)
++{
++ spin_unlock_irq(&pool->lock);
++}
++#endif
++
++
+ #ifdef CONFIG_DEBUG_OBJECTS_WORK
+
+ static struct debug_obj_descr work_debug_descr;
+@@ -548,7 +582,7 @@
+ * @wq: the target workqueue
+ * @node: the node ID
+ *
+- * This must be called with any of wq_pool_mutex, wq->mutex or sched RCU
++ * This must be called with any of wq_pool_mutex, wq->mutex or RCU
+ * read locked.
+ * If the pwq needs to be used beyond the locking in effect, the caller is
+ * responsible for guaranteeing that the pwq stays online.
+@@ -692,8 +726,8 @@
+ * @work: the work item of interest
+ *
+ * Pools are created and destroyed under wq_pool_mutex, and allows read
+- * access under sched-RCU read lock. As such, this function should be
+- * called under wq_pool_mutex or with preemption disabled.
++ * access under RCU read lock. As such, this function should be
++ * called under wq_pool_mutex or inside of a rcu_read_lock() region.
+ *
+ * All fields of the returned pool are accessible as long as the above
+ * mentioned locking is in effect. If the returned pool needs to be used
+@@ -830,50 +864,45 @@
+ */
+ static void wake_up_worker(struct worker_pool *pool)
+ {
+- struct worker *worker = first_idle_worker(pool);
++ struct worker *worker;
++
++ rt_lock_idle_list(pool);
++
++ worker = first_idle_worker(pool);
+
+ if (likely(worker))
+ wake_up_process(worker->task);
++
++ rt_unlock_idle_list(pool);
+ }
+
+ /**
+- * wq_worker_waking_up - a worker is waking up
++ * wq_worker_running - a worker is running again
+ * @task: task waking up
+- * @cpu: CPU @task is waking up to
+- *
+- * This function is called during try_to_wake_up() when a worker is
+- * being awoken.
+ *
+- * CONTEXT:
+- * spin_lock_irq(rq->lock)
++ * This function is called when a worker returns from schedule()
+ */
+-void wq_worker_waking_up(struct task_struct *task, int cpu)
++void wq_worker_running(struct task_struct *task)
+ {
+ struct worker *worker = kthread_data(task);
+
+- if (!(worker->flags & WORKER_NOT_RUNNING)) {
+- WARN_ON_ONCE(worker->pool->cpu != cpu);
++ if (!worker->sleeping)
++ return;
++ if (!(worker->flags & WORKER_NOT_RUNNING))
+ atomic_inc(&worker->pool->nr_running);
+- }
++ worker->sleeping = 0;
+ }
+
+ /**
+ * wq_worker_sleeping - a worker is going to sleep
+ * @task: task going to sleep
+ *
+- * This function is called during schedule() when a busy worker is
+- * going to sleep. Worker on the same cpu can be woken up by
+- * returning pointer to its task.
+- *
+- * CONTEXT:
+- * spin_lock_irq(rq->lock)
+- *
+- * Return:
+- * Worker task on @cpu to wake up, %NULL if none.
++ * This function is called from schedule() when a busy worker is
++ * going to sleep.
+ */
+-struct task_struct *wq_worker_sleeping(struct task_struct *task)
++void wq_worker_sleeping(struct task_struct *task)
+ {
+- struct worker *worker = kthread_data(task), *to_wakeup = NULL;
++ struct worker *worker = kthread_data(task);
+ struct worker_pool *pool;
+
+ /*
+@@ -882,29 +911,26 @@
+ * checking NOT_RUNNING.
+ */
+ if (worker->flags & WORKER_NOT_RUNNING)
+- return NULL;
++ return;
+
+ pool = worker->pool;
+
+- /* this can only happen on the local cpu */
+- if (WARN_ON_ONCE(pool->cpu != raw_smp_processor_id()))
+- return NULL;
++ if (WARN_ON_ONCE(worker->sleeping))
++ return;
++
++ worker->sleeping = 1;
+
+ /*
+ * The counterpart of the following dec_and_test, implied mb,
+ * worklist not empty test sequence is in insert_work().
+ * Please read comment there.
+- *
+- * NOT_RUNNING is clear. This means that we're bound to and
+- * running on the local cpu w/ rq lock held and preemption
+- * disabled, which in turn means that none else could be
+- * manipulating idle_list, so dereferencing idle_list without pool
+- * lock is safe.
+ */
+ if (atomic_dec_and_test(&pool->nr_running) &&
+- !list_empty(&pool->worklist))
+- to_wakeup = first_idle_worker(pool);
+- return to_wakeup ? to_wakeup->task : NULL;
++ !list_empty(&pool->worklist)) {
++ sched_lock_idle_list(pool);
++ wake_up_worker(pool);
++ sched_unlock_idle_list(pool);
++ }
+ }
+
+ /**
+@@ -1098,12 +1124,14 @@
+ {
+ if (pwq) {
+ /*
+- * As both pwqs and pools are sched-RCU protected, the
++ * As both pwqs and pools are RCU protected, the
+ * following lock operations are safe.
+ */
+- spin_lock_irq(&pwq->pool->lock);
++ rcu_read_lock();
++ local_spin_lock_irq(pendingb_lock, &pwq->pool->lock);
+ put_pwq(pwq);
+- spin_unlock_irq(&pwq->pool->lock);
++ local_spin_unlock_irq(pendingb_lock, &pwq->pool->lock);
++ rcu_read_unlock();
+ }
+ }
+
+@@ -1207,7 +1235,7 @@
+ struct worker_pool *pool;
+ struct pool_workqueue *pwq;
+
+- local_irq_save(*flags);
++ local_lock_irqsave(pendingb_lock, *flags);
+
+ /* try to steal the timer if it exists */
+ if (is_dwork) {
+@@ -1226,6 +1254,7 @@
+ if (!test_and_set_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work)))
+ return 0;
+
++ rcu_read_lock();
+ /*
+ * The queueing is in progress, or it is already queued. Try to
+ * steal it from ->worklist without clearing WORK_STRUCT_PENDING.
+@@ -1264,14 +1293,16 @@
+ set_work_pool_and_keep_pending(work, pool->id);
+
+ spin_unlock(&pool->lock);
++ rcu_read_unlock();
+ return 1;
+ }
+ spin_unlock(&pool->lock);
+ fail:
+- local_irq_restore(*flags);
++ rcu_read_unlock();
++ local_unlock_irqrestore(pendingb_lock, *flags);
+ if (work_is_canceling(work))
+ return -ENOENT;
+- cpu_relax();
++ cpu_chill();
+ return -EAGAIN;
+ }
+
+@@ -1373,7 +1404,7 @@
+ * queued or lose PENDING. Grabbing PENDING and queueing should
+ * happen with IRQ disabled.
+ */
+- WARN_ON_ONCE(!irqs_disabled());
++ WARN_ON_ONCE_NONRT(!irqs_disabled());
+
+ debug_work_activate(work);
+
+@@ -1381,6 +1412,7 @@
+ if (unlikely(wq->flags & __WQ_DRAINING) &&
+ WARN_ON_ONCE(!is_chained_work(wq)))
+ return;
++ rcu_read_lock();
+ retry:
+ if (req_cpu == WORK_CPU_UNBOUND)
+ cpu = wq_select_unbound_cpu(raw_smp_processor_id());
+@@ -1437,10 +1469,8 @@
+ /* pwq determined, queue */
+ trace_workqueue_queue_work(req_cpu, pwq, work);
+
+- if (WARN_ON(!list_empty(&work->entry))) {
+- spin_unlock(&pwq->pool->lock);
+- return;
+- }
++ if (WARN_ON(!list_empty(&work->entry)))
++ goto out;
+
+ pwq->nr_in_flight[pwq->work_color]++;
+ work_flags = work_color_to_flags(pwq->work_color);
+@@ -1458,7 +1488,9 @@
+
+ insert_work(pwq, work, worklist, work_flags);
+
++out:
+ spin_unlock(&pwq->pool->lock);
++ rcu_read_unlock();
+ }
+
+ /**
+@@ -1478,14 +1510,14 @@
+ bool ret = false;
+ unsigned long flags;
+
+- local_irq_save(flags);
++ local_lock_irqsave(pendingb_lock,flags);
+
+ if (!test_and_set_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work))) {
+ __queue_work(cpu, wq, work);
+ ret = true;
+ }
+
+- local_irq_restore(flags);
++ local_unlock_irqrestore(pendingb_lock, flags);
+ return ret;
+ }
+ EXPORT_SYMBOL(queue_work_on);
+@@ -1552,14 +1584,14 @@
+ unsigned long flags;
+
+ /* read the comment in __queue_work() */
+- local_irq_save(flags);
++ local_lock_irqsave(pendingb_lock, flags);
+
+ if (!test_and_set_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work))) {
+ __queue_delayed_work(cpu, wq, dwork, delay);
+ ret = true;
+ }
+
+- local_irq_restore(flags);
++ local_unlock_irqrestore(pendingb_lock, flags);
+ return ret;
+ }
+ EXPORT_SYMBOL(queue_delayed_work_on);
+@@ -1594,7 +1626,7 @@
+
+ if (likely(ret >= 0)) {
+ __queue_delayed_work(cpu, wq, dwork, delay);
+- local_irq_restore(flags);
++ local_unlock_irqrestore(pendingb_lock, flags);
+ }
+
+ /* -ENOENT from try_to_grab_pending() becomes %true */
+@@ -1627,7 +1659,9 @@
+ worker->last_active = jiffies;
+
+ /* idle_list is LIFO */
++ rt_lock_idle_list(pool);
+ list_add(&worker->entry, &pool->idle_list);
++ rt_unlock_idle_list(pool);
+
+ if (too_many_workers(pool) && !timer_pending(&pool->idle_timer))
+ mod_timer(&pool->idle_timer, jiffies + IDLE_WORKER_TIMEOUT);
+@@ -1660,7 +1694,9 @@
+ return;
+ worker_clr_flags(worker, WORKER_IDLE);
+ pool->nr_idle--;
++ rt_lock_idle_list(pool);
+ list_del_init(&worker->entry);
++ rt_unlock_idle_list(pool);
+ }
+
+ static struct worker *alloc_worker(int node)
+@@ -1826,7 +1862,9 @@
+ pool->nr_workers--;
+ pool->nr_idle--;
+
++ rt_lock_idle_list(pool);
+ list_del_init(&worker->entry);
++ rt_unlock_idle_list(pool);
+ worker->flags |= WORKER_DIE;
+ wake_up_process(worker->task);
+ }
+@@ -2785,14 +2823,14 @@
+
+ might_sleep();
+
+- local_irq_disable();
++ rcu_read_lock();
+ pool = get_work_pool(work);
+ if (!pool) {
+- local_irq_enable();
++ rcu_read_unlock();
+ return false;
+ }
+
+- spin_lock(&pool->lock);
++ spin_lock_irq(&pool->lock);
+ /* see the comment in try_to_grab_pending() with the same code */
+ pwq = get_work_pwq(work);
+ if (pwq) {
+@@ -2821,10 +2859,11 @@
+ else
+ lock_map_acquire_read(&pwq->wq->lockdep_map);
+ lock_map_release(&pwq->wq->lockdep_map);
+-
++ rcu_read_unlock();
+ return true;
+ already_gone:
+ spin_unlock_irq(&pool->lock);
++ rcu_read_unlock();
+ return false;
+ }
+
+@@ -2911,7 +2950,7 @@
+
+ /* tell other tasks trying to grab @work to back off */
+ mark_work_canceling(work);
+- local_irq_restore(flags);
++ local_unlock_irqrestore(pendingb_lock, flags);
+
+ flush_work(work);
+ clear_work_data(work);
+@@ -2966,10 +3005,10 @@
+ */
+ bool flush_delayed_work(struct delayed_work *dwork)
+ {
+- local_irq_disable();
++ local_lock_irq(pendingb_lock);
+ if (del_timer_sync(&dwork->timer))
+ __queue_work(dwork->cpu, dwork->wq, &dwork->work);
+- local_irq_enable();
++ local_unlock_irq(pendingb_lock);
+ return flush_work(&dwork->work);
+ }
+ EXPORT_SYMBOL(flush_delayed_work);
+@@ -3004,7 +3043,7 @@
+
+ set_work_pool_and_clear_pending(&dwork->work,
+ get_work_pool_id(&dwork->work));
+- local_irq_restore(flags);
++ local_unlock_irqrestore(pendingb_lock, flags);
+ return ret;
+ }
+ EXPORT_SYMBOL(cancel_delayed_work);
+@@ -3233,7 +3272,7 @@
+ * put_unbound_pool - put a worker_pool
+ * @pool: worker_pool to put
+ *
+- * Put @pool. If its refcnt reaches zero, it gets destroyed in sched-RCU
++ * Put @pool. If its refcnt reaches zero, it gets destroyed in RCU
+ * safe manner. get_unbound_pool() calls this function on its failure path
+ * and this function should be able to release pools which went through,
+ * successfully or not, init_worker_pool().
+@@ -3287,8 +3326,8 @@
+ del_timer_sync(&pool->idle_timer);
+ del_timer_sync(&pool->mayday_timer);
+
+- /* sched-RCU protected to allow dereferences from get_work_pool() */
+- call_rcu_sched(&pool->rcu, rcu_free_pool);
++ /* RCU protected to allow dereferences from get_work_pool() */
++ call_rcu(&pool->rcu, rcu_free_pool);
+ }
+
+ /**
+@@ -3395,14 +3434,14 @@
+ put_unbound_pool(pool);
+ mutex_unlock(&wq_pool_mutex);
+
+- call_rcu_sched(&pwq->rcu, rcu_free_pwq);
++ call_rcu(&pwq->rcu, rcu_free_pwq);
+
+ /*
+ * If we're the last pwq going away, @wq is already dead and no one
+ * is gonna access it anymore. Schedule RCU free.
+ */
+ if (is_last)
+- call_rcu_sched(&wq->rcu, rcu_free_wq);
++ call_rcu(&wq->rcu, rcu_free_wq);
+ }
+
+ /**
+@@ -4052,7 +4091,7 @@
+ * The base ref is never dropped on per-cpu pwqs. Directly
+ * schedule RCU free.
+ */
+- call_rcu_sched(&wq->rcu, rcu_free_wq);
++ call_rcu(&wq->rcu, rcu_free_wq);
+ } else {
+ /*
+ * We're the sole accessor of @wq at this point. Directly
+@@ -4145,7 +4184,8 @@
+ struct pool_workqueue *pwq;
+ bool ret;
+
+- rcu_read_lock_sched();
++ rcu_read_lock();
++ preempt_disable();
+
+ if (cpu == WORK_CPU_UNBOUND)
+ cpu = smp_processor_id();
+@@ -4156,7 +4196,8 @@
+ pwq = unbound_pwq_by_node(wq, cpu_to_node(cpu));
+
+ ret = !list_empty(&pwq->delayed_works);
+- rcu_read_unlock_sched();
++ preempt_enable();
++ rcu_read_unlock();
+
+ return ret;
+ }
+@@ -4182,15 +4223,15 @@
+ if (work_pending(work))
+ ret |= WORK_BUSY_PENDING;
+
+- local_irq_save(flags);
++ rcu_read_lock();
+ pool = get_work_pool(work);
+ if (pool) {
+- spin_lock(&pool->lock);
++ spin_lock_irqsave(&pool->lock, flags);
+ if (find_worker_executing_work(pool, work))
+ ret |= WORK_BUSY_RUNNING;
+- spin_unlock(&pool->lock);
++ spin_unlock_irqrestore(&pool->lock, flags);
+ }
+- local_irq_restore(flags);
++ rcu_read_unlock();
+
+ return ret;
+ }
+@@ -4379,7 +4420,7 @@
+ unsigned long flags;
+ int pi;
+
+- rcu_read_lock_sched();
++ rcu_read_lock();
+
+ pr_info("Showing busy workqueues and worker pools:\n");
+
+@@ -4432,7 +4473,7 @@
+ spin_unlock_irqrestore(&pool->lock, flags);
+ }
+
+- rcu_read_unlock_sched();
++ rcu_read_unlock();
+ }
+
+ /*
+@@ -4770,16 +4811,16 @@
+ * nr_active is monotonically decreasing. It's safe
+ * to peek without lock.
+ */
+- rcu_read_lock_sched();
++ rcu_read_lock();
+ for_each_pwq(pwq, wq) {
+ WARN_ON_ONCE(pwq->nr_active < 0);
+ if (pwq->nr_active) {
+ busy = true;
+- rcu_read_unlock_sched();
++ rcu_read_unlock();
+ goto out_unlock;
+ }
+ }
+- rcu_read_unlock_sched();
++ rcu_read_unlock();
+ }
+ out_unlock:
+ mutex_unlock(&wq_pool_mutex);
+@@ -4969,7 +5010,8 @@
+ const char *delim = "";
+ int node, written = 0;
+
+- rcu_read_lock_sched();
++ get_online_cpus();
++ rcu_read_lock();
+ for_each_node(node) {
+ written += scnprintf(buf + written, PAGE_SIZE - written,
+ "%s%d:%d", delim, node,
+@@ -4977,7 +5019,8 @@
+ delim = " ";
+ }
+ written += scnprintf(buf + written, PAGE_SIZE - written, "\n");
+- rcu_read_unlock_sched();
++ rcu_read_unlock();
++ put_online_cpus();
+
+ return written;
+ }
+diff -Nur linux-4.8.15.orig/kernel/workqueue_internal.h linux-4.8.15/kernel/workqueue_internal.h
+--- linux-4.8.15.orig/kernel/workqueue_internal.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/kernel/workqueue_internal.h 2017-01-01 17:07:16.063429015 +0100
+@@ -43,6 +43,7 @@
+ unsigned long last_active; /* L: last active timestamp */
+ unsigned int flags; /* X: flags */
+ int id; /* I: worker id */
++ int sleeping; /* None */
+
+ /*
+ * Opaque string set with work_set_desc(). Printed out with task
+@@ -68,7 +69,7 @@
+ * Scheduler hooks for concurrency managed workqueue. Only to be used from
+ * sched/core.c and workqueue.c.
+ */
+-void wq_worker_waking_up(struct task_struct *task, int cpu);
+-struct task_struct *wq_worker_sleeping(struct task_struct *task);
++void wq_worker_running(struct task_struct *task);
++void wq_worker_sleeping(struct task_struct *task);
+
+ #endif /* _KERNEL_WORKQUEUE_INTERNAL_H */
+diff -Nur linux-4.8.15.orig/lib/debugobjects.c linux-4.8.15/lib/debugobjects.c
+--- linux-4.8.15.orig/lib/debugobjects.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/lib/debugobjects.c 2017-01-01 17:07:16.063429015 +0100
+@@ -308,7 +308,10 @@
+ struct debug_obj *obj;
+ unsigned long flags;
+
+- fill_pool();
++#ifdef CONFIG_PREEMPT_RT_FULL
++ if (preempt_count() == 0 && !irqs_disabled())
++#endif
++ fill_pool();
+
+ db = get_bucket((unsigned long) addr);
+
+diff -Nur linux-4.8.15.orig/lib/idr.c linux-4.8.15/lib/idr.c
+--- linux-4.8.15.orig/lib/idr.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/lib/idr.c 2017-01-01 17:07:16.067429274 +0100
+@@ -30,6 +30,7 @@
+ #include <linux/idr.h>
+ #include <linux/spinlock.h>
+ #include <linux/percpu.h>
++#include <linux/locallock.h>
+
+ #define MAX_IDR_SHIFT (sizeof(int) * 8 - 1)
+ #define MAX_IDR_BIT (1U << MAX_IDR_SHIFT)
+@@ -45,6 +46,37 @@
+ static DEFINE_PER_CPU(int, idr_preload_cnt);
+ static DEFINE_SPINLOCK(simple_ida_lock);
+
++#ifdef CONFIG_PREEMPT_RT_FULL
++static DEFINE_LOCAL_IRQ_LOCK(idr_lock);
++
++static inline void idr_preload_lock(void)
++{
++ local_lock(idr_lock);
++}
++
++static inline void idr_preload_unlock(void)
++{
++ local_unlock(idr_lock);
++}
++
++void idr_preload_end(void)
++{
++ idr_preload_unlock();
++}
++EXPORT_SYMBOL(idr_preload_end);
++#else
++static inline void idr_preload_lock(void)
++{
++ preempt_disable();
++}
++
++static inline void idr_preload_unlock(void)
++{
++ preempt_enable();
++}
++#endif
++
++
+ /* the maximum ID which can be allocated given idr->layers */
+ static int idr_max(int layers)
+ {
+@@ -115,14 +147,14 @@
+ * context. See idr_preload() for details.
+ */
+ if (!in_interrupt()) {
+- preempt_disable();
++ idr_preload_lock();
+ new = __this_cpu_read(idr_preload_head);
+ if (new) {
+ __this_cpu_write(idr_preload_head, new->ary[0]);
+ __this_cpu_dec(idr_preload_cnt);
+ new->ary[0] = NULL;
+ }
+- preempt_enable();
++ idr_preload_unlock();
+ if (new)
+ return new;
+ }
+@@ -366,7 +398,6 @@
+ idr_mark_full(pa, id);
+ }
+
+-
+ /**
+ * idr_preload - preload for idr_alloc()
+ * @gfp_mask: allocation mask to use for preloading
+@@ -401,7 +432,7 @@
+ WARN_ON_ONCE(in_interrupt());
+ might_sleep_if(gfpflags_allow_blocking(gfp_mask));
+
+- preempt_disable();
++ idr_preload_lock();
+
+ /*
+ * idr_alloc() is likely to succeed w/o full idr_layer buffer and
+@@ -413,9 +444,9 @@
+ while (__this_cpu_read(idr_preload_cnt) < MAX_IDR_FREE) {
+ struct idr_layer *new;
+
+- preempt_enable();
++ idr_preload_unlock();
+ new = kmem_cache_zalloc(idr_layer_cache, gfp_mask);
+- preempt_disable();
++ idr_preload_lock();
+ if (!new)
+ break;
+
+diff -Nur linux-4.8.15.orig/lib/irq_poll.c linux-4.8.15/lib/irq_poll.c
+--- linux-4.8.15.orig/lib/irq_poll.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/lib/irq_poll.c 2017-01-01 17:07:16.067429274 +0100
+@@ -36,6 +36,7 @@
+ list_add_tail(&iop->list, this_cpu_ptr(&blk_cpu_iopoll));
+ __raise_softirq_irqoff(IRQ_POLL_SOFTIRQ);
+ local_irq_restore(flags);
++ preempt_check_resched_rt();
+ }
+ EXPORT_SYMBOL(irq_poll_sched);
+
+@@ -71,6 +72,7 @@
+ local_irq_save(flags);
+ __irq_poll_complete(iop);
+ local_irq_restore(flags);
++ preempt_check_resched_rt();
+ }
+ EXPORT_SYMBOL(irq_poll_complete);
+
+@@ -95,6 +97,7 @@
+ }
+
+ local_irq_enable();
++ preempt_check_resched_rt();
+
+ /* Even though interrupts have been re-enabled, this
+ * access is safe because interrupts can only add new
+@@ -132,6 +135,7 @@
+ __raise_softirq_irqoff(IRQ_POLL_SOFTIRQ);
+
+ local_irq_enable();
++ preempt_check_resched_rt();
+ }
+
+ /**
+@@ -199,6 +203,7 @@
+ this_cpu_ptr(&blk_cpu_iopoll));
+ __raise_softirq_irqoff(IRQ_POLL_SOFTIRQ);
+ local_irq_enable();
++ preempt_check_resched_rt();
+ }
+
+ return NOTIFY_OK;
+diff -Nur linux-4.8.15.orig/lib/Kconfig linux-4.8.15/lib/Kconfig
+--- linux-4.8.15.orig/lib/Kconfig 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/lib/Kconfig 2017-01-01 17:07:16.063429015 +0100
+@@ -400,6 +400,7 @@
+
+ config CPUMASK_OFFSTACK
+ bool "Force CPU masks off stack" if DEBUG_PER_CPU_MAPS
++ depends on !PREEMPT_RT_FULL
+ help
+ Use dynamic allocation for cpumask_var_t, instead of putting
+ them on the stack. This is a bit more expensive, but avoids
+diff -Nur linux-4.8.15.orig/lib/Kconfig.debug linux-4.8.15/lib/Kconfig.debug
+--- linux-4.8.15.orig/lib/Kconfig.debug 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/lib/Kconfig.debug 2017-01-01 17:07:16.063429015 +0100
+@@ -977,6 +977,7 @@
+ config DEBUG_PREEMPT
+ bool "Debug preemptible kernel"
+ depends on DEBUG_KERNEL && PREEMPT && TRACE_IRQFLAGS_SUPPORT
++ select USING_GET_LOCK_PARENT_IP
+ default y
+ help
+ If you say Y here then the kernel will use a debug variant of the
+@@ -1159,8 +1160,17 @@
+
+ endmenu # lock debugging
+
++config USING_GET_LOCK_PARENT_IP
++ bool
++ help
++ Enables the use of the function get_lock_parent_ip() that
++ will use __builtin_return_address(n) with n > 0 causing
++ some gcc warnings. When this is selected, those warnings
++ will be suppressed.
++
+ config TRACE_IRQFLAGS
+ bool
++ select USING_GET_LOCK_PARENT_IP
+ help
+ Enables hooks to interrupt enabling and disabling for
+ either tracing or lock debugging.
+diff -Nur linux-4.8.15.orig/lib/locking-selftest.c linux-4.8.15/lib/locking-selftest.c
+--- linux-4.8.15.orig/lib/locking-selftest.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/lib/locking-selftest.c 2017-01-01 17:07:16.067429274 +0100
+@@ -590,6 +590,8 @@
+ #include "locking-selftest-spin-hardirq.h"
+ GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_hard_spin)
+
++#ifndef CONFIG_PREEMPT_RT_FULL
++
+ #include "locking-selftest-rlock-hardirq.h"
+ GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_hard_rlock)
+
+@@ -605,9 +607,12 @@
+ #include "locking-selftest-wlock-softirq.h"
+ GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_soft_wlock)
+
++#endif
++
+ #undef E1
+ #undef E2
+
++#ifndef CONFIG_PREEMPT_RT_FULL
+ /*
+ * Enabling hardirqs with a softirq-safe lock held:
+ */
+@@ -640,6 +645,8 @@
+ #undef E1
+ #undef E2
+
++#endif
++
+ /*
+ * Enabling irqs with an irq-safe lock held:
+ */
+@@ -663,6 +670,8 @@
+ #include "locking-selftest-spin-hardirq.h"
+ GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_hard_spin)
+
++#ifndef CONFIG_PREEMPT_RT_FULL
++
+ #include "locking-selftest-rlock-hardirq.h"
+ GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_hard_rlock)
+
+@@ -678,6 +687,8 @@
+ #include "locking-selftest-wlock-softirq.h"
+ GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_soft_wlock)
+
++#endif
++
+ #undef E1
+ #undef E2
+
+@@ -709,6 +720,8 @@
+ #include "locking-selftest-spin-hardirq.h"
+ GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_hard_spin)
+
++#ifndef CONFIG_PREEMPT_RT_FULL
++
+ #include "locking-selftest-rlock-hardirq.h"
+ GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_hard_rlock)
+
+@@ -724,6 +737,8 @@
+ #include "locking-selftest-wlock-softirq.h"
+ GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_soft_wlock)
+
++#endif
++
+ #undef E1
+ #undef E2
+ #undef E3
+@@ -757,6 +772,8 @@
+ #include "locking-selftest-spin-hardirq.h"
+ GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_hard_spin)
+
++#ifndef CONFIG_PREEMPT_RT_FULL
++
+ #include "locking-selftest-rlock-hardirq.h"
+ GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_hard_rlock)
+
+@@ -772,10 +789,14 @@
+ #include "locking-selftest-wlock-softirq.h"
+ GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_soft_wlock)
+
++#endif
++
+ #undef E1
+ #undef E2
+ #undef E3
+
++#ifndef CONFIG_PREEMPT_RT_FULL
++
+ /*
+ * read-lock / write-lock irq inversion.
+ *
+@@ -838,6 +859,10 @@
+ #undef E2
+ #undef E3
+
++#endif
++
++#ifndef CONFIG_PREEMPT_RT_FULL
++
+ /*
+ * read-lock / write-lock recursion that is actually safe.
+ */
+@@ -876,6 +901,8 @@
+ #undef E2
+ #undef E3
+
++#endif
++
+ /*
+ * read-lock / write-lock recursion that is unsafe.
+ */
+@@ -1858,6 +1885,7 @@
+
+ printk(" --------------------------------------------------------------------------\n");
+
++#ifndef CONFIG_PREEMPT_RT_FULL
+ /*
+ * irq-context testcases:
+ */
+@@ -1870,6 +1898,28 @@
+
+ DO_TESTCASE_6x2("irq read-recursion", irq_read_recursion);
+ // DO_TESTCASE_6x2B("irq read-recursion #2", irq_read_recursion2);
++#else
++ /* On -rt, we only do hardirq context test for raw spinlock */
++ DO_TESTCASE_1B("hard-irqs-on + irq-safe-A", irqsafe1_hard_spin, 12);
++ DO_TESTCASE_1B("hard-irqs-on + irq-safe-A", irqsafe1_hard_spin, 21);
++
++ DO_TESTCASE_1B("hard-safe-A + irqs-on", irqsafe2B_hard_spin, 12);
++ DO_TESTCASE_1B("hard-safe-A + irqs-on", irqsafe2B_hard_spin, 21);
++
++ DO_TESTCASE_1B("hard-safe-A + unsafe-B #1", irqsafe3_hard_spin, 123);
++ DO_TESTCASE_1B("hard-safe-A + unsafe-B #1", irqsafe3_hard_spin, 132);
++ DO_TESTCASE_1B("hard-safe-A + unsafe-B #1", irqsafe3_hard_spin, 213);
++ DO_TESTCASE_1B("hard-safe-A + unsafe-B #1", irqsafe3_hard_spin, 231);
++ DO_TESTCASE_1B("hard-safe-A + unsafe-B #1", irqsafe3_hard_spin, 312);
++ DO_TESTCASE_1B("hard-safe-A + unsafe-B #1", irqsafe3_hard_spin, 321);
++
++ DO_TESTCASE_1B("hard-safe-A + unsafe-B #2", irqsafe4_hard_spin, 123);
++ DO_TESTCASE_1B("hard-safe-A + unsafe-B #2", irqsafe4_hard_spin, 132);
++ DO_TESTCASE_1B("hard-safe-A + unsafe-B #2", irqsafe4_hard_spin, 213);
++ DO_TESTCASE_1B("hard-safe-A + unsafe-B #2", irqsafe4_hard_spin, 231);
++ DO_TESTCASE_1B("hard-safe-A + unsafe-B #2", irqsafe4_hard_spin, 312);
++ DO_TESTCASE_1B("hard-safe-A + unsafe-B #2", irqsafe4_hard_spin, 321);
++#endif
+
+ ww_tests();
+
+diff -Nur linux-4.8.15.orig/lib/percpu_ida.c linux-4.8.15/lib/percpu_ida.c
+--- linux-4.8.15.orig/lib/percpu_ida.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/lib/percpu_ida.c 2017-01-01 17:07:16.067429274 +0100
+@@ -26,6 +26,9 @@
+ #include <linux/string.h>
+ #include <linux/spinlock.h>
+ #include <linux/percpu_ida.h>
++#include <linux/locallock.h>
++
++static DEFINE_LOCAL_IRQ_LOCK(irq_off_lock);
+
+ struct percpu_ida_cpu {
+ /*
+@@ -148,13 +151,13 @@
+ unsigned long flags;
+ int tag;
+
+- local_irq_save(flags);
++ local_lock_irqsave(irq_off_lock, flags);
+ tags = this_cpu_ptr(pool->tag_cpu);
+
+ /* Fastpath */
+ tag = alloc_local_tag(tags);
+ if (likely(tag >= 0)) {
+- local_irq_restore(flags);
++ local_unlock_irqrestore(irq_off_lock, flags);
+ return tag;
+ }
+
+@@ -173,6 +176,7 @@
+
+ if (!tags->nr_free)
+ alloc_global_tags(pool, tags);
++
+ if (!tags->nr_free)
+ steal_tags(pool, tags);
+
+@@ -184,7 +188,7 @@
+ }
+
+ spin_unlock(&pool->lock);
+- local_irq_restore(flags);
++ local_unlock_irqrestore(irq_off_lock, flags);
+
+ if (tag >= 0 || state == TASK_RUNNING)
+ break;
+@@ -196,7 +200,7 @@
+
+ schedule();
+
+- local_irq_save(flags);
++ local_lock_irqsave(irq_off_lock, flags);
+ tags = this_cpu_ptr(pool->tag_cpu);
+ }
+ if (state != TASK_RUNNING)
+@@ -221,7 +225,7 @@
+
+ BUG_ON(tag >= pool->nr_tags);
+
+- local_irq_save(flags);
++ local_lock_irqsave(irq_off_lock, flags);
+ tags = this_cpu_ptr(pool->tag_cpu);
+
+ spin_lock(&tags->lock);
+@@ -253,7 +257,7 @@
+ spin_unlock(&pool->lock);
+ }
+
+- local_irq_restore(flags);
++ local_unlock_irqrestore(irq_off_lock, flags);
+ }
+ EXPORT_SYMBOL_GPL(percpu_ida_free);
+
+@@ -345,7 +349,7 @@
+ struct percpu_ida_cpu *remote;
+ unsigned cpu, i, err = 0;
+
+- local_irq_save(flags);
++ local_lock_irqsave(irq_off_lock, flags);
+ for_each_possible_cpu(cpu) {
+ remote = per_cpu_ptr(pool->tag_cpu, cpu);
+ spin_lock(&remote->lock);
+@@ -367,7 +371,7 @@
+ }
+ spin_unlock(&pool->lock);
+ out:
+- local_irq_restore(flags);
++ local_unlock_irqrestore(irq_off_lock, flags);
+ return err;
+ }
+ EXPORT_SYMBOL_GPL(percpu_ida_for_each_free);
+diff -Nur linux-4.8.15.orig/lib/radix-tree.c linux-4.8.15/lib/radix-tree.c
+--- linux-4.8.15.orig/lib/radix-tree.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/lib/radix-tree.c 2017-01-01 17:07:16.067429274 +0100
+@@ -290,13 +290,14 @@
+ * succeed in getting a node here (and never reach
+ * kmem_cache_alloc)
+ */
+- rtp = this_cpu_ptr(&radix_tree_preloads);
++ rtp = &get_cpu_var(radix_tree_preloads);
+ if (rtp->nr) {
+ ret = rtp->nodes;
+ rtp->nodes = ret->private_data;
+ ret->private_data = NULL;
+ rtp->nr--;
+ }
++ put_cpu_var(radix_tree_preloads);
+ /*
+ * Update the allocation stack trace as this is more useful
+ * for debugging.
+@@ -336,6 +337,7 @@
+ call_rcu(&node->rcu_head, radix_tree_node_rcu_free);
+ }
+
++#ifndef CONFIG_PREEMPT_RT_FULL
+ /*
+ * Load up this CPU's radix_tree_node buffer with sufficient objects to
+ * ensure that the addition of a single element in the tree cannot fail. On
+@@ -455,6 +457,7 @@
+
+ return __radix_tree_preload(gfp_mask, nr_nodes);
+ }
++#endif
+
+ /*
+ * The maximum index which can be stored in a radix tree
+diff -Nur linux-4.8.15.orig/lib/scatterlist.c linux-4.8.15/lib/scatterlist.c
+--- linux-4.8.15.orig/lib/scatterlist.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/lib/scatterlist.c 2017-01-01 17:07:16.067429274 +0100
+@@ -620,7 +620,7 @@
+ flush_kernel_dcache_page(miter->page);
+
+ if (miter->__flags & SG_MITER_ATOMIC) {
+- WARN_ON_ONCE(preemptible());
++ WARN_ON_ONCE(!pagefault_disabled());
+ kunmap_atomic(miter->addr);
+ } else
+ kunmap(miter->page);
+@@ -664,7 +664,7 @@
+ if (!sg_miter_skip(&miter, skip))
+ return false;
+
+- local_irq_save(flags);
++ local_irq_save_nort(flags);
+
+ while (sg_miter_next(&miter) && offset < buflen) {
+ unsigned int len;
+@@ -681,7 +681,7 @@
+
+ sg_miter_stop(&miter);
+
+- local_irq_restore(flags);
++ local_irq_restore_nort(flags);
+ return offset;
+ }
+ EXPORT_SYMBOL(sg_copy_buffer);
+diff -Nur linux-4.8.15.orig/lib/smp_processor_id.c linux-4.8.15/lib/smp_processor_id.c
+--- linux-4.8.15.orig/lib/smp_processor_id.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/lib/smp_processor_id.c 2017-01-01 17:07:16.067429274 +0100
+@@ -39,8 +39,9 @@
+ if (!printk_ratelimit())
+ goto out_enable;
+
+- printk(KERN_ERR "BUG: using %s%s() in preemptible [%08x] code: %s/%d\n",
+- what1, what2, preempt_count() - 1, current->comm, current->pid);
++ printk(KERN_ERR "BUG: using %s%s() in preemptible [%08x %08x] code: %s/%d\n",
++ what1, what2, preempt_count() - 1, __migrate_disabled(current),
++ current->comm, current->pid);
+
+ print_symbol("caller is %s\n", (long)__builtin_return_address(0));
+ dump_stack();
+diff -Nur linux-4.8.15.orig/mm/backing-dev.c linux-4.8.15/mm/backing-dev.c
+--- linux-4.8.15.orig/mm/backing-dev.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/mm/backing-dev.c 2017-01-01 17:07:16.103431597 +0100
+@@ -457,9 +457,9 @@
+ {
+ unsigned long flags;
+
+- local_irq_save(flags);
++ local_irq_save_nort(flags);
+ if (!atomic_dec_and_lock(&congested->refcnt, &cgwb_lock)) {
+- local_irq_restore(flags);
++ local_irq_restore_nort(flags);
+ return;
+ }
+
+diff -Nur linux-4.8.15.orig/mm/compaction.c linux-4.8.15/mm/compaction.c
+--- linux-4.8.15.orig/mm/compaction.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/mm/compaction.c 2017-01-01 17:07:16.103431597 +0100
+@@ -1585,10 +1585,12 @@
+ block_start_pfn(cc->migrate_pfn, cc->order);
+
+ if (cc->last_migrated_pfn < current_block_start) {
+- cpu = get_cpu();
++ cpu = get_cpu_light();
++ local_lock_irq(swapvec_lock);
+ lru_add_drain_cpu(cpu);
++ local_unlock_irq(swapvec_lock);
+ drain_local_pages(zone);
+- put_cpu();
++ put_cpu_light();
+ /* No more flushing until we migrate again */
+ cc->last_migrated_pfn = 0;
+ }
+diff -Nur linux-4.8.15.orig/mm/filemap.c linux-4.8.15/mm/filemap.c
+--- linux-4.8.15.orig/mm/filemap.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/mm/filemap.c 2017-01-01 17:07:16.103431597 +0100
+@@ -159,9 +159,12 @@
+ * node->private_list is protected by
+ * mapping->tree_lock.
+ */
+- if (!list_empty(&node->private_list))
+- list_lru_del(&workingset_shadow_nodes,
++ if (!list_empty(&node->private_list)) {
++ local_lock(workingset_shadow_lock);
++ list_lru_del(&__workingset_shadow_nodes,
+ &node->private_list);
++ local_unlock(workingset_shadow_lock);
++ }
+ }
+ return 0;
+ }
+@@ -217,8 +220,10 @@
+ if (!dax_mapping(mapping) && !workingset_node_pages(node) &&
+ list_empty(&node->private_list)) {
+ node->private_data = mapping;
+- list_lru_add(&workingset_shadow_nodes,
+- &node->private_list);
++ local_lock(workingset_shadow_lock);
++ list_lru_add(&__workingset_shadow_nodes,
++ &node->private_list);
++ local_unlock(workingset_shadow_lock);
+ }
+ }
+
+diff -Nur linux-4.8.15.orig/mm/highmem.c linux-4.8.15/mm/highmem.c
+--- linux-4.8.15.orig/mm/highmem.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/mm/highmem.c 2017-01-01 17:07:16.103431597 +0100
+@@ -29,10 +29,11 @@
+ #include <linux/kgdb.h>
+ #include <asm/tlbflush.h>
+
+-
++#ifndef CONFIG_PREEMPT_RT_FULL
+ #if defined(CONFIG_HIGHMEM) || defined(CONFIG_X86_32)
+ DEFINE_PER_CPU(int, __kmap_atomic_idx);
+ #endif
++#endif
+
+ /*
+ * Virtual_count is not a pure "count".
+@@ -107,8 +108,9 @@
+ unsigned long totalhigh_pages __read_mostly;
+ EXPORT_SYMBOL(totalhigh_pages);
+
+-
++#ifndef CONFIG_PREEMPT_RT_FULL
+ EXPORT_PER_CPU_SYMBOL(__kmap_atomic_idx);
++#endif
+
+ unsigned int nr_free_highpages (void)
+ {
+diff -Nur linux-4.8.15.orig/mm/Kconfig linux-4.8.15/mm/Kconfig
+--- linux-4.8.15.orig/mm/Kconfig 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/mm/Kconfig 2017-01-01 17:07:16.103431597 +0100
+@@ -410,7 +410,7 @@
+
+ config TRANSPARENT_HUGEPAGE
+ bool "Transparent Hugepage Support"
+- depends on HAVE_ARCH_TRANSPARENT_HUGEPAGE
++ depends on HAVE_ARCH_TRANSPARENT_HUGEPAGE && !PREEMPT_RT_FULL
+ select COMPACTION
+ select RADIX_TREE_MULTIORDER
+ help
+diff -Nur linux-4.8.15.orig/mm/memcontrol.c linux-4.8.15/mm/memcontrol.c
+--- linux-4.8.15.orig/mm/memcontrol.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/mm/memcontrol.c 2017-01-01 17:07:16.107431847 +0100
+@@ -67,6 +67,7 @@
+ #include <net/sock.h>
+ #include <net/ip.h>
+ #include "slab.h"
++#include <linux/locallock.h>
+
+ #include <asm/uaccess.h>
+
+@@ -92,6 +93,8 @@
+ #define do_swap_account 0
+ #endif
+
++static DEFINE_LOCAL_IRQ_LOCK(event_lock);
++
+ /* Whether legacy memory+swap accounting is active */
+ static bool do_memsw_account(void)
+ {
+@@ -1724,6 +1727,7 @@
+ #define FLUSHING_CACHED_CHARGE 0
+ };
+ static DEFINE_PER_CPU(struct memcg_stock_pcp, memcg_stock);
++static DEFINE_LOCAL_IRQ_LOCK(memcg_stock_ll);
+ static DEFINE_MUTEX(percpu_charge_mutex);
+
+ /**
+@@ -1746,7 +1750,7 @@
+ if (nr_pages > CHARGE_BATCH)
+ return ret;
+
+- local_irq_save(flags);
++ local_lock_irqsave(memcg_stock_ll, flags);
+
+ stock = this_cpu_ptr(&memcg_stock);
+ if (memcg == stock->cached && stock->nr_pages >= nr_pages) {
+@@ -1754,7 +1758,7 @@
+ ret = true;
+ }
+
+- local_irq_restore(flags);
++ local_unlock_irqrestore(memcg_stock_ll, flags);
+
+ return ret;
+ }
+@@ -1781,13 +1785,13 @@
+ struct memcg_stock_pcp *stock;
+ unsigned long flags;
+
+- local_irq_save(flags);
++ local_lock_irqsave(memcg_stock_ll, flags);
+
+ stock = this_cpu_ptr(&memcg_stock);
+ drain_stock(stock);
+ clear_bit(FLUSHING_CACHED_CHARGE, &stock->flags);
+
+- local_irq_restore(flags);
++ local_unlock_irqrestore(memcg_stock_ll, flags);
+ }
+
+ /*
+@@ -1799,7 +1803,7 @@
+ struct memcg_stock_pcp *stock;
+ unsigned long flags;
+
+- local_irq_save(flags);
++ local_lock_irqsave(memcg_stock_ll, flags);
+
+ stock = this_cpu_ptr(&memcg_stock);
+ if (stock->cached != memcg) { /* reset if necessary */
+@@ -1808,7 +1812,7 @@
+ }
+ stock->nr_pages += nr_pages;
+
+- local_irq_restore(flags);
++ local_unlock_irqrestore(memcg_stock_ll, flags);
+ }
+
+ /*
+@@ -1824,7 +1828,7 @@
+ return;
+ /* Notify other cpus that system-wide "drain" is running */
+ get_online_cpus();
+- curcpu = get_cpu();
++ curcpu = get_cpu_light();
+ for_each_online_cpu(cpu) {
+ struct memcg_stock_pcp *stock = &per_cpu(memcg_stock, cpu);
+ struct mem_cgroup *memcg;
+@@ -1841,7 +1845,7 @@
+ schedule_work_on(cpu, &stock->work);
+ }
+ }
+- put_cpu();
++ put_cpu_light();
+ put_online_cpus();
+ mutex_unlock(&percpu_charge_mutex);
+ }
+@@ -4575,12 +4579,12 @@
+
+ ret = 0;
+
+- local_irq_disable();
++ local_lock_irq(event_lock);
+ mem_cgroup_charge_statistics(to, page, compound, nr_pages);
+ memcg_check_events(to, page);
+ mem_cgroup_charge_statistics(from, page, compound, -nr_pages);
+ memcg_check_events(from, page);
+- local_irq_enable();
++ local_unlock_irq(event_lock);
+ out_unlock:
+ unlock_page(page);
+ out:
+@@ -5453,10 +5457,10 @@
+
+ commit_charge(page, memcg, lrucare);
+
+- local_irq_disable();
++ local_lock_irq(event_lock);
+ mem_cgroup_charge_statistics(memcg, page, compound, nr_pages);
+ memcg_check_events(memcg, page);
+- local_irq_enable();
++ local_unlock_irq(event_lock);
+
+ if (do_memsw_account() && PageSwapCache(page)) {
+ swp_entry_t entry = { .val = page_private(page) };
+@@ -5512,14 +5516,14 @@
+ memcg_oom_recover(memcg);
+ }
+
+- local_irq_save(flags);
++ local_lock_irqsave(event_lock, flags);
+ __this_cpu_sub(memcg->stat->count[MEM_CGROUP_STAT_RSS], nr_anon);
+ __this_cpu_sub(memcg->stat->count[MEM_CGROUP_STAT_CACHE], nr_file);
+ __this_cpu_sub(memcg->stat->count[MEM_CGROUP_STAT_RSS_HUGE], nr_huge);
+ __this_cpu_add(memcg->stat->events[MEM_CGROUP_EVENTS_PGPGOUT], pgpgout);
+ __this_cpu_add(memcg->stat->nr_page_events, nr_pages);
+ memcg_check_events(memcg, dummy_page);
+- local_irq_restore(flags);
++ local_unlock_irqrestore(event_lock, flags);
+
+ if (!mem_cgroup_is_root(memcg))
+ css_put_many(&memcg->css, nr_pages);
+@@ -5674,10 +5678,10 @@
+
+ commit_charge(newpage, memcg, false);
+
+- local_irq_save(flags);
++ local_lock_irqsave(event_lock, flags);
+ mem_cgroup_charge_statistics(memcg, newpage, compound, nr_pages);
+ memcg_check_events(memcg, newpage);
+- local_irq_restore(flags);
++ local_unlock_irqrestore(event_lock, flags);
+ }
+
+ DEFINE_STATIC_KEY_FALSE(memcg_sockets_enabled_key);
+@@ -5854,6 +5858,7 @@
+ {
+ struct mem_cgroup *memcg, *swap_memcg;
+ unsigned short oldid;
++ unsigned long flags;
+
+ VM_BUG_ON_PAGE(PageLRU(page), page);
+ VM_BUG_ON_PAGE(page_count(page), page);
+@@ -5894,12 +5899,16 @@
+ * important here to have the interrupts disabled because it is the
+ * only synchronisation we have for udpating the per-CPU variables.
+ */
++ local_lock_irqsave(event_lock, flags);
++#ifndef CONFIG_PREEMPT_RT_BASE
+ VM_BUG_ON(!irqs_disabled());
++#endif
+ mem_cgroup_charge_statistics(memcg, page, false, -1);
+ memcg_check_events(memcg, page);
+
+ if (!mem_cgroup_is_root(memcg))
+ css_put(&memcg->css);
++ local_unlock_irqrestore(event_lock, flags);
+ }
+
+ /*
+diff -Nur linux-4.8.15.orig/mm/mmu_context.c linux-4.8.15/mm/mmu_context.c
+--- linux-4.8.15.orig/mm/mmu_context.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/mm/mmu_context.c 2017-01-01 17:07:16.107431847 +0100
+@@ -23,6 +23,7 @@
+ struct task_struct *tsk = current;
+
+ task_lock(tsk);
++ preempt_disable_rt();
+ active_mm = tsk->active_mm;
+ if (active_mm != mm) {
+ atomic_inc(&mm->mm_count);
+@@ -30,6 +31,7 @@
+ }
+ tsk->mm = mm;
+ switch_mm(active_mm, mm, tsk);
++ preempt_enable_rt();
+ task_unlock(tsk);
+ #ifdef finish_arch_post_lock_switch
+ finish_arch_post_lock_switch();
+diff -Nur linux-4.8.15.orig/mm/page_alloc.c linux-4.8.15/mm/page_alloc.c
+--- linux-4.8.15.orig/mm/page_alloc.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/mm/page_alloc.c 2017-01-01 17:07:16.111432108 +0100
+@@ -61,6 +61,7 @@
+ #include <linux/page_ext.h>
+ #include <linux/hugetlb.h>
+ #include <linux/sched/rt.h>
++#include <linux/locallock.h>
+ #include <linux/page_owner.h>
+ #include <linux/kthread.h>
+ #include <linux/memcontrol.h>
+@@ -276,6 +277,18 @@
+ EXPORT_SYMBOL(nr_online_nodes);
+ #endif
+
++static DEFINE_LOCAL_IRQ_LOCK(pa_lock);
++
++#ifdef CONFIG_PREEMPT_RT_BASE
++# define cpu_lock_irqsave(cpu, flags) \
++ local_lock_irqsave_on(pa_lock, flags, cpu)
++# define cpu_unlock_irqrestore(cpu, flags) \
++ local_unlock_irqrestore_on(pa_lock, flags, cpu)
++#else
++# define cpu_lock_irqsave(cpu, flags) local_irq_save(flags)
++# define cpu_unlock_irqrestore(cpu, flags) local_irq_restore(flags)
++#endif
++
+ int page_group_by_mobility_disabled __read_mostly;
+
+ #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
+@@ -1056,7 +1069,7 @@
+ #endif /* CONFIG_DEBUG_VM */
+
+ /*
+- * Frees a number of pages from the PCP lists
++ * Frees a number of pages which have been collected from the pcp lists.
+ * Assumes all pages on list are in same zone, and of same order.
+ * count is the number of pages to free.
+ *
+@@ -1067,19 +1080,58 @@
+ * pinned" detection logic.
+ */
+ static void free_pcppages_bulk(struct zone *zone, int count,
+- struct per_cpu_pages *pcp)
++ struct list_head *list)
+ {
+- int migratetype = 0;
+- int batch_free = 0;
+ unsigned long nr_scanned;
+ bool isolated_pageblocks;
++ unsigned long flags;
++
++ spin_lock_irqsave(&zone->lock, flags);
+
+- spin_lock(&zone->lock);
+ isolated_pageblocks = has_isolate_pageblock(zone);
+ nr_scanned = node_page_state(zone->zone_pgdat, NR_PAGES_SCANNED);
+ if (nr_scanned)
+ __mod_node_page_state(zone->zone_pgdat, NR_PAGES_SCANNED, -nr_scanned);
+
++ while (!list_empty(list)) {
++ struct page *page;
++ int mt; /* migratetype of the to-be-freed page */
++
++ page = list_first_entry(list, struct page, lru);
++ /* must delete as __free_one_page list manipulates */
++ list_del(&page->lru);
++
++ mt = get_pcppage_migratetype(page);
++ /* MIGRATE_ISOLATE page should not go to pcplists */
++ VM_BUG_ON_PAGE(is_migrate_isolate(mt), page);
++ /* Pageblock could have been isolated meanwhile */
++ if (unlikely(isolated_pageblocks))
++ mt = get_pageblock_migratetype(page);
++
++ if (bulkfree_pcp_prepare(page))
++ continue;
++
++ __free_one_page(page, page_to_pfn(page), zone, 0, mt);
++ trace_mm_page_pcpu_drain(page, 0, mt);
++ count--;
++ }
++ WARN_ON(count != 0);
++ spin_unlock_irqrestore(&zone->lock, flags);
++}
++
++/*
++ * Moves a number of pages from the PCP lists to free list which
++ * is freed outside of the locked region.
++ *
++ * Assumes all pages on list are in same zone, and of same order.
++ * count is the number of pages to free.
++ */
++static void isolate_pcp_pages(int count, struct per_cpu_pages *src,
++ struct list_head *dst)
++{
++ int migratetype = 0;
++ int batch_free = 0;
++
+ while (count) {
+ struct page *page;
+ struct list_head *list;
+@@ -1095,7 +1147,7 @@
+ batch_free++;
+ if (++migratetype == MIGRATE_PCPTYPES)
+ migratetype = 0;
+- list = &pcp->lists[migratetype];
++ list = &src->lists[migratetype];
+ } while (list_empty(list));
+
+ /* This is the only non-empty list. Free them all. */
+@@ -1103,27 +1155,12 @@
+ batch_free = count;
+
+ do {
+- int mt; /* migratetype of the to-be-freed page */
+-
+ page = list_last_entry(list, struct page, lru);
+- /* must delete as __free_one_page list manipulates */
+ list_del(&page->lru);
+
+- mt = get_pcppage_migratetype(page);
+- /* MIGRATE_ISOLATE page should not go to pcplists */
+- VM_BUG_ON_PAGE(is_migrate_isolate(mt), page);
+- /* Pageblock could have been isolated meanwhile */
+- if (unlikely(isolated_pageblocks))
+- mt = get_pageblock_migratetype(page);
+-
+- if (bulkfree_pcp_prepare(page))
+- continue;
+-
+- __free_one_page(page, page_to_pfn(page), zone, 0, mt);
+- trace_mm_page_pcpu_drain(page, 0, mt);
++ list_add(&page->lru, dst);
+ } while (--count && --batch_free && !list_empty(list));
+ }
+- spin_unlock(&zone->lock);
+ }
+
+ static void free_one_page(struct zone *zone,
+@@ -1132,7 +1169,9 @@
+ int migratetype)
+ {
+ unsigned long nr_scanned;
+- spin_lock(&zone->lock);
++ unsigned long flags;
++
++ spin_lock_irqsave(&zone->lock, flags);
+ nr_scanned = node_page_state(zone->zone_pgdat, NR_PAGES_SCANNED);
+ if (nr_scanned)
+ __mod_node_page_state(zone->zone_pgdat, NR_PAGES_SCANNED, -nr_scanned);
+@@ -1142,7 +1181,7 @@
+ migratetype = get_pfnblock_migratetype(page, pfn);
+ }
+ __free_one_page(page, pfn, zone, order, migratetype);
+- spin_unlock(&zone->lock);
++ spin_unlock_irqrestore(&zone->lock, flags);
+ }
+
+ static void __meminit __init_single_page(struct page *page, unsigned long pfn,
+@@ -1228,10 +1267,10 @@
+ return;
+
+ migratetype = get_pfnblock_migratetype(page, pfn);
+- local_irq_save(flags);
++ local_lock_irqsave(pa_lock, flags);
+ __count_vm_events(PGFREE, 1 << order);
+ free_one_page(page_zone(page), page, pfn, order, migratetype);
+- local_irq_restore(flags);
++ local_unlock_irqrestore(pa_lock, flags);
+ }
+
+ static void __init __free_pages_boot_core(struct page *page, unsigned int order)
+@@ -2219,16 +2258,18 @@
+ void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp)
+ {
+ unsigned long flags;
++ LIST_HEAD(dst);
+ int to_drain, batch;
+
+- local_irq_save(flags);
++ local_lock_irqsave(pa_lock, flags);
+ batch = READ_ONCE(pcp->batch);
+ to_drain = min(pcp->count, batch);
+ if (to_drain > 0) {
+- free_pcppages_bulk(zone, to_drain, pcp);
++ isolate_pcp_pages(to_drain, pcp, &dst);
+ pcp->count -= to_drain;
+ }
+- local_irq_restore(flags);
++ local_unlock_irqrestore(pa_lock, flags);
++ free_pcppages_bulk(zone, to_drain, &dst);
+ }
+ #endif
+
+@@ -2244,16 +2285,21 @@
+ unsigned long flags;
+ struct per_cpu_pageset *pset;
+ struct per_cpu_pages *pcp;
++ LIST_HEAD(dst);
++ int count;
+
+- local_irq_save(flags);
++ cpu_lock_irqsave(cpu, flags);
+ pset = per_cpu_ptr(zone->pageset, cpu);
+
+ pcp = &pset->pcp;
+- if (pcp->count) {
+- free_pcppages_bulk(zone, pcp->count, pcp);
++ count = pcp->count;
++ if (count) {
++ isolate_pcp_pages(count, pcp, &dst);
+ pcp->count = 0;
+ }
+- local_irq_restore(flags);
++ cpu_unlock_irqrestore(cpu, flags);
++ if (count)
++ free_pcppages_bulk(zone, count, &dst);
+ }
+
+ /*
+@@ -2339,8 +2385,17 @@
+ else
+ cpumask_clear_cpu(cpu, &cpus_with_pcps);
+ }
++#ifndef CONFIG_PREEMPT_RT_BASE
+ on_each_cpu_mask(&cpus_with_pcps, (smp_call_func_t) drain_local_pages,
+ zone, 1);
++#else
++ for_each_cpu(cpu, &cpus_with_pcps) {
++ if (zone)
++ drain_pages_zone(cpu, zone);
++ else
++ drain_pages(cpu);
++ }
++#endif
+ }
+
+ #ifdef CONFIG_HIBERNATION
+@@ -2400,7 +2455,7 @@
+
+ migratetype = get_pfnblock_migratetype(page, pfn);
+ set_pcppage_migratetype(page, migratetype);
+- local_irq_save(flags);
++ local_lock_irqsave(pa_lock, flags);
+ __count_vm_event(PGFREE);
+
+ /*
+@@ -2426,12 +2481,17 @@
+ pcp->count++;
+ if (pcp->count >= pcp->high) {
+ unsigned long batch = READ_ONCE(pcp->batch);
+- free_pcppages_bulk(zone, batch, pcp);
++ LIST_HEAD(dst);
++
++ isolate_pcp_pages(batch, pcp, &dst);
+ pcp->count -= batch;
++ local_unlock_irqrestore(pa_lock, flags);
++ free_pcppages_bulk(zone, batch, &dst);
++ return;
+ }
+
+ out:
+- local_irq_restore(flags);
++ local_unlock_irqrestore(pa_lock, flags);
+ }
+
+ /*
+@@ -2568,7 +2628,7 @@
+ struct per_cpu_pages *pcp;
+ struct list_head *list;
+
+- local_irq_save(flags);
++ local_lock_irqsave(pa_lock, flags);
+ do {
+ pcp = &this_cpu_ptr(zone->pageset)->pcp;
+ list = &pcp->lists[migratetype];
+@@ -2595,7 +2655,7 @@
+ * allocate greater than order-1 page units with __GFP_NOFAIL.
+ */
+ WARN_ON_ONCE((gfp_flags & __GFP_NOFAIL) && (order > 1));
+- spin_lock_irqsave(&zone->lock, flags);
++ local_spin_lock_irqsave(pa_lock, &zone->lock, flags);
+
+ do {
+ page = NULL;
+@@ -2607,22 +2667,24 @@
+ if (!page)
+ page = __rmqueue(zone, order, migratetype);
+ } while (page && check_new_pages(page, order));
+- spin_unlock(&zone->lock);
+- if (!page)
++ if (!page) {
++ spin_unlock(&zone->lock);
+ goto failed;
++ }
+ __mod_zone_freepage_state(zone, -(1 << order),
+ get_pcppage_migratetype(page));
++ spin_unlock(&zone->lock);
+ }
+
+ __count_zid_vm_events(PGALLOC, page_zonenum(page), 1 << order);
+ zone_statistics(preferred_zone, zone, gfp_flags);
+- local_irq_restore(flags);
++ local_unlock_irqrestore(pa_lock, flags);
+
+ VM_BUG_ON_PAGE(bad_range(zone, page), page);
+ return page;
+
+ failed:
+- local_irq_restore(flags);
++ local_unlock_irqrestore(pa_lock, flags);
+ return NULL;
+ }
+
+@@ -6538,7 +6600,9 @@
+ int cpu = (unsigned long)hcpu;
+
+ if (action == CPU_DEAD || action == CPU_DEAD_FROZEN) {
++ local_lock_irq_on(swapvec_lock, cpu);
+ lru_add_drain_cpu(cpu);
++ local_unlock_irq_on(swapvec_lock, cpu);
+ drain_pages(cpu);
+
+ /*
+@@ -6564,6 +6628,7 @@
+ void __init page_alloc_init(void)
+ {
+ hotcpu_notifier(page_alloc_cpu_notify, 0);
++ local_irq_lock_init(pa_lock);
+ }
+
+ /*
+@@ -7380,7 +7445,7 @@
+ struct per_cpu_pageset *pset;
+
+ /* avoid races with drain_pages() */
+- local_irq_save(flags);
++ local_lock_irqsave(pa_lock, flags);
+ if (zone->pageset != &boot_pageset) {
+ for_each_online_cpu(cpu) {
+ pset = per_cpu_ptr(zone->pageset, cpu);
+@@ -7389,7 +7454,7 @@
+ free_percpu(zone->pageset);
+ zone->pageset = &boot_pageset;
+ }
+- local_irq_restore(flags);
++ local_unlock_irqrestore(pa_lock, flags);
+ }
+
+ #ifdef CONFIG_MEMORY_HOTREMOVE
+diff -Nur linux-4.8.15.orig/mm/slab.h linux-4.8.15/mm/slab.h
+--- linux-4.8.15.orig/mm/slab.h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/mm/slab.h 2017-01-01 17:07:16.111432108 +0100
+@@ -426,7 +426,11 @@
+ * The slab lists for all objects.
+ */
+ struct kmem_cache_node {
++#ifdef CONFIG_SLUB
++ raw_spinlock_t list_lock;
++#else
+ spinlock_t list_lock;
++#endif
+
+ #ifdef CONFIG_SLAB
+ struct list_head slabs_partial; /* partial list first, better asm code */
+diff -Nur linux-4.8.15.orig/mm/slub.c linux-4.8.15/mm/slub.c
+--- linux-4.8.15.orig/mm/slub.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/mm/slub.c 2017-01-01 17:07:16.111432108 +0100
+@@ -1145,7 +1145,7 @@
+ unsigned long uninitialized_var(flags);
+ int ret = 0;
+
+- spin_lock_irqsave(&n->list_lock, flags);
++ raw_spin_lock_irqsave(&n->list_lock, flags);
+ slab_lock(page);
+
+ if (s->flags & SLAB_CONSISTENCY_CHECKS) {
+@@ -1180,7 +1180,7 @@
+ bulk_cnt, cnt);
+
+ slab_unlock(page);
+- spin_unlock_irqrestore(&n->list_lock, flags);
++ raw_spin_unlock_irqrestore(&n->list_lock, flags);
+ if (!ret)
+ slab_fix(s, "Object at 0x%p not freed", object);
+ return ret;
+@@ -1308,6 +1308,12 @@
+
+ #endif /* CONFIG_SLUB_DEBUG */
+
++struct slub_free_list {
++ raw_spinlock_t lock;
++ struct list_head list;
++};
++static DEFINE_PER_CPU(struct slub_free_list, slub_free_list);
++
+ /*
+ * Hooks for other subsystems that check memory allocations. In a typical
+ * production configuration these hooks all should produce no code at all.
+@@ -1527,10 +1533,17 @@
+ void *start, *p;
+ int idx, order;
+ bool shuffle;
++ bool enableirqs = false;
+
+ flags &= gfp_allowed_mask;
+
+ if (gfpflags_allow_blocking(flags))
++ enableirqs = true;
++#ifdef CONFIG_PREEMPT_RT_FULL
++ if (system_state == SYSTEM_RUNNING)
++ enableirqs = true;
++#endif
++ if (enableirqs)
+ local_irq_enable();
+
+ flags |= s->allocflags;
+@@ -1605,7 +1618,7 @@
+ page->frozen = 1;
+
+ out:
+- if (gfpflags_allow_blocking(flags))
++ if (enableirqs)
+ local_irq_disable();
+ if (!page)
+ return NULL;
+@@ -1664,6 +1677,16 @@
+ __free_pages(page, order);
+ }
+
++static void free_delayed(struct list_head *h)
++{
++ while(!list_empty(h)) {
++ struct page *page = list_first_entry(h, struct page, lru);
++
++ list_del(&page->lru);
++ __free_slab(page->slab_cache, page);
++ }
++}
++
+ #define need_reserve_slab_rcu \
+ (sizeof(((struct page *)NULL)->lru) < sizeof(struct rcu_head))
+
+@@ -1695,6 +1718,12 @@
+ }
+
+ call_rcu(head, rcu_free_slab);
++ } else if (irqs_disabled()) {
++ struct slub_free_list *f = this_cpu_ptr(&slub_free_list);
++
++ raw_spin_lock(&f->lock);
++ list_add(&page->lru, &f->list);
++ raw_spin_unlock(&f->lock);
+ } else
+ __free_slab(s, page);
+ }
+@@ -1802,7 +1831,7 @@
+ if (!n || !n->nr_partial)
+ return NULL;
+
+- spin_lock(&n->list_lock);
++ raw_spin_lock(&n->list_lock);
+ list_for_each_entry_safe(page, page2, &n->partial, lru) {
+ void *t;
+
+@@ -1827,7 +1856,7 @@
+ break;
+
+ }
+- spin_unlock(&n->list_lock);
++ raw_spin_unlock(&n->list_lock);
+ return object;
+ }
+
+@@ -2073,7 +2102,7 @@
+ * that acquire_slab() will see a slab page that
+ * is frozen
+ */
+- spin_lock(&n->list_lock);
++ raw_spin_lock(&n->list_lock);
+ }
+ } else {
+ m = M_FULL;
+@@ -2084,7 +2113,7 @@
+ * slabs from diagnostic functions will not see
+ * any frozen slabs.
+ */
+- spin_lock(&n->list_lock);
++ raw_spin_lock(&n->list_lock);
+ }
+ }
+
+@@ -2119,7 +2148,7 @@
+ goto redo;
+
+ if (lock)
+- spin_unlock(&n->list_lock);
++ raw_spin_unlock(&n->list_lock);
+
+ if (m == M_FREE) {
+ stat(s, DEACTIVATE_EMPTY);
+@@ -2151,10 +2180,10 @@
+ n2 = get_node(s, page_to_nid(page));
+ if (n != n2) {
+ if (n)
+- spin_unlock(&n->list_lock);
++ raw_spin_unlock(&n->list_lock);
+
+ n = n2;
+- spin_lock(&n->list_lock);
++ raw_spin_lock(&n->list_lock);
+ }
+
+ do {
+@@ -2183,7 +2212,7 @@
+ }
+
+ if (n)
+- spin_unlock(&n->list_lock);
++ raw_spin_unlock(&n->list_lock);
+
+ while (discard_page) {
+ page = discard_page;
+@@ -2222,14 +2251,21 @@
+ pobjects = oldpage->pobjects;
+ pages = oldpage->pages;
+ if (drain && pobjects > s->cpu_partial) {
++ struct slub_free_list *f;
+ unsigned long flags;
++ LIST_HEAD(tofree);
+ /*
+ * partial array is full. Move the existing
+ * set to the per node partial list.
+ */
+ local_irq_save(flags);
+ unfreeze_partials(s, this_cpu_ptr(s->cpu_slab));
++ f = this_cpu_ptr(&slub_free_list);
++ raw_spin_lock(&f->lock);
++ list_splice_init(&f->list, &tofree);
++ raw_spin_unlock(&f->lock);
+ local_irq_restore(flags);
++ free_delayed(&tofree);
+ oldpage = NULL;
+ pobjects = 0;
+ pages = 0;
+@@ -2301,7 +2337,22 @@
+
+ static void flush_all(struct kmem_cache *s)
+ {
++ LIST_HEAD(tofree);
++ int cpu;
++
+ on_each_cpu_cond(has_cpu_slab, flush_cpu_slab, s, 1, GFP_ATOMIC);
++ for_each_online_cpu(cpu) {
++ struct slub_free_list *f;
++
++ if (!has_cpu_slab(cpu, s))
++ continue;
++
++ f = &per_cpu(slub_free_list, cpu);
++ raw_spin_lock_irq(&f->lock);
++ list_splice_init(&f->list, &tofree);
++ raw_spin_unlock_irq(&f->lock);
++ free_delayed(&tofree);
++ }
+ }
+
+ /*
+@@ -2337,10 +2388,10 @@
+ unsigned long x = 0;
+ struct page *page;
+
+- spin_lock_irqsave(&n->list_lock, flags);
++ raw_spin_lock_irqsave(&n->list_lock, flags);
+ list_for_each_entry(page, &n->partial, lru)
+ x += get_count(page);
+- spin_unlock_irqrestore(&n->list_lock, flags);
++ raw_spin_unlock_irqrestore(&n->list_lock, flags);
+ return x;
+ }
+ #endif /* CONFIG_SLUB_DEBUG || CONFIG_SYSFS */
+@@ -2478,8 +2529,10 @@
+ * already disabled (which is the case for bulk allocation).
+ */
+ static void *___slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node,
+- unsigned long addr, struct kmem_cache_cpu *c)
++ unsigned long addr, struct kmem_cache_cpu *c,
++ struct list_head *to_free)
+ {
++ struct slub_free_list *f;
+ void *freelist;
+ struct page *page;
+
+@@ -2539,6 +2592,13 @@
+ VM_BUG_ON(!c->page->frozen);
+ c->freelist = get_freepointer(s, freelist);
+ c->tid = next_tid(c->tid);
++
++out:
++ f = this_cpu_ptr(&slub_free_list);
++ raw_spin_lock(&f->lock);
++ list_splice_init(&f->list, to_free);
++ raw_spin_unlock(&f->lock);
++
+ return freelist;
+
+ new_slab:
+@@ -2570,7 +2630,7 @@
+ deactivate_slab(s, page, get_freepointer(s, freelist));
+ c->page = NULL;
+ c->freelist = NULL;
+- return freelist;
++ goto out;
+ }
+
+ /*
+@@ -2582,6 +2642,7 @@
+ {
+ void *p;
+ unsigned long flags;
++ LIST_HEAD(tofree);
+
+ local_irq_save(flags);
+ #ifdef CONFIG_PREEMPT
+@@ -2593,8 +2654,9 @@
+ c = this_cpu_ptr(s->cpu_slab);
+ #endif
+
+- p = ___slab_alloc(s, gfpflags, node, addr, c);
++ p = ___slab_alloc(s, gfpflags, node, addr, c, &tofree);
+ local_irq_restore(flags);
++ free_delayed(&tofree);
+ return p;
+ }
+
+@@ -2780,7 +2842,7 @@
+
+ do {
+ if (unlikely(n)) {
+- spin_unlock_irqrestore(&n->list_lock, flags);
++ raw_spin_unlock_irqrestore(&n->list_lock, flags);
+ n = NULL;
+ }
+ prior = page->freelist;
+@@ -2812,7 +2874,7 @@
+ * Otherwise the list_lock will synchronize with
+ * other processors updating the list of slabs.
+ */
+- spin_lock_irqsave(&n->list_lock, flags);
++ raw_spin_lock_irqsave(&n->list_lock, flags);
+
+ }
+ }
+@@ -2854,7 +2916,7 @@
+ add_partial(n, page, DEACTIVATE_TO_TAIL);
+ stat(s, FREE_ADD_PARTIAL);
+ }
+- spin_unlock_irqrestore(&n->list_lock, flags);
++ raw_spin_unlock_irqrestore(&n->list_lock, flags);
+ return;
+
+ slab_empty:
+@@ -2869,7 +2931,7 @@
+ remove_full(s, n, page);
+ }
+
+- spin_unlock_irqrestore(&n->list_lock, flags);
++ raw_spin_unlock_irqrestore(&n->list_lock, flags);
+ stat(s, FREE_SLAB);
+ discard_slab(s, page);
+ }
+@@ -3074,6 +3136,7 @@
+ void **p)
+ {
+ struct kmem_cache_cpu *c;
++ LIST_HEAD(to_free);
+ int i;
+
+ /* memcg and kmem_cache debug support */
+@@ -3097,7 +3160,7 @@
+ * of re-populating per CPU c->freelist
+ */
+ p[i] = ___slab_alloc(s, flags, NUMA_NO_NODE,
+- _RET_IP_, c);
++ _RET_IP_, c, &to_free);
+ if (unlikely(!p[i]))
+ goto error;
+
+@@ -3109,6 +3172,7 @@
+ }
+ c->tid = next_tid(c->tid);
+ local_irq_enable();
++ free_delayed(&to_free);
+
+ /* Clear memory outside IRQ disabled fastpath loop */
+ if (unlikely(flags & __GFP_ZERO)) {
+@@ -3256,7 +3320,7 @@
+ init_kmem_cache_node(struct kmem_cache_node *n)
+ {
+ n->nr_partial = 0;
+- spin_lock_init(&n->list_lock);
++ raw_spin_lock_init(&n->list_lock);
+ INIT_LIST_HEAD(&n->partial);
+ #ifdef CONFIG_SLUB_DEBUG
+ atomic_long_set(&n->nr_slabs, 0);
+@@ -3600,6 +3664,10 @@
+ const char *text)
+ {
+ #ifdef CONFIG_SLUB_DEBUG
++#ifdef CONFIG_PREEMPT_RT_BASE
++ /* XXX move out of irq-off section */
++ slab_err(s, page, text, s->name);
++#else
+ void *addr = page_address(page);
+ void *p;
+ unsigned long *map = kzalloc(BITS_TO_LONGS(page->objects) *
+@@ -3620,6 +3688,7 @@
+ slab_unlock(page);
+ kfree(map);
+ #endif
++#endif
+ }
+
+ /*
+@@ -3633,7 +3702,7 @@
+ struct page *page, *h;
+
+ BUG_ON(irqs_disabled());
+- spin_lock_irq(&n->list_lock);
++ raw_spin_lock_irq(&n->list_lock);
+ list_for_each_entry_safe(page, h, &n->partial, lru) {
+ if (!page->inuse) {
+ remove_partial(n, page);
+@@ -3643,7 +3712,7 @@
+ "Objects remaining in %s on __kmem_cache_shutdown()");
+ }
+ }
+- spin_unlock_irq(&n->list_lock);
++ raw_spin_unlock_irq(&n->list_lock);
+
+ list_for_each_entry_safe(page, h, &discard, lru)
+ discard_slab(s, page);
+@@ -3901,7 +3970,7 @@
+ for (i = 0; i < SHRINK_PROMOTE_MAX; i++)
+ INIT_LIST_HEAD(promote + i);
+
+- spin_lock_irqsave(&n->list_lock, flags);
++ raw_spin_lock_irqsave(&n->list_lock, flags);
+
+ /*
+ * Build lists of slabs to discard or promote.
+@@ -3932,7 +4001,7 @@
+ for (i = SHRINK_PROMOTE_MAX - 1; i >= 0; i--)
+ list_splice(promote + i, &n->partial);
+
+- spin_unlock_irqrestore(&n->list_lock, flags);
++ raw_spin_unlock_irqrestore(&n->list_lock, flags);
+
+ /* Release empty slabs */
+ list_for_each_entry_safe(page, t, &discard, lru)
+@@ -4108,6 +4177,12 @@
+ {
+ static __initdata struct kmem_cache boot_kmem_cache,
+ boot_kmem_cache_node;
++ int cpu;
++
++ for_each_possible_cpu(cpu) {
++ raw_spin_lock_init(&per_cpu(slub_free_list, cpu).lock);
++ INIT_LIST_HEAD(&per_cpu(slub_free_list, cpu).list);
++ }
+
+ if (debug_guardpage_minorder())
+ slub_max_order = 0;
+@@ -4354,7 +4429,7 @@
+ struct page *page;
+ unsigned long flags;
+
+- spin_lock_irqsave(&n->list_lock, flags);
++ raw_spin_lock_irqsave(&n->list_lock, flags);
+
+ list_for_each_entry(page, &n->partial, lru) {
+ validate_slab_slab(s, page, map);
+@@ -4376,7 +4451,7 @@
+ s->name, count, atomic_long_read(&n->nr_slabs));
+
+ out:
+- spin_unlock_irqrestore(&n->list_lock, flags);
++ raw_spin_unlock_irqrestore(&n->list_lock, flags);
+ return count;
+ }
+
+@@ -4564,12 +4639,12 @@
+ if (!atomic_long_read(&n->nr_slabs))
+ continue;
+
+- spin_lock_irqsave(&n->list_lock, flags);
++ raw_spin_lock_irqsave(&n->list_lock, flags);
+ list_for_each_entry(page, &n->partial, lru)
+ process_slab(&t, s, page, alloc, map);
+ list_for_each_entry(page, &n->full, lru)
+ process_slab(&t, s, page, alloc, map);
+- spin_unlock_irqrestore(&n->list_lock, flags);
++ raw_spin_unlock_irqrestore(&n->list_lock, flags);
+ }
+
+ for (i = 0; i < t.count; i++) {
+diff -Nur linux-4.8.15.orig/mm/swap.c linux-4.8.15/mm/swap.c
+--- linux-4.8.15.orig/mm/swap.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/mm/swap.c 2017-01-01 17:07:16.111432108 +0100
+@@ -32,6 +32,7 @@
+ #include <linux/memcontrol.h>
+ #include <linux/gfp.h>
+ #include <linux/uio.h>
++#include <linux/locallock.h>
+ #include <linux/hugetlb.h>
+ #include <linux/page_idle.h>
+
+@@ -50,6 +51,8 @@
+ #ifdef CONFIG_SMP
+ static DEFINE_PER_CPU(struct pagevec, activate_page_pvecs);
+ #endif
++static DEFINE_LOCAL_IRQ_LOCK(rotate_lock);
++DEFINE_LOCAL_IRQ_LOCK(swapvec_lock);
+
+ /*
+ * This path almost never happens for VM activity - pages are normally
+@@ -240,11 +243,11 @@
+ unsigned long flags;
+
+ get_page(page);
+- local_irq_save(flags);
++ local_lock_irqsave(rotate_lock, flags);
+ pvec = this_cpu_ptr(&lru_rotate_pvecs);
+ if (!pagevec_add(pvec, page) || PageCompound(page))
+ pagevec_move_tail(pvec);
+- local_irq_restore(flags);
++ local_unlock_irqrestore(rotate_lock, flags);
+ }
+ }
+
+@@ -294,12 +297,13 @@
+ {
+ page = compound_head(page);
+ if (PageLRU(page) && !PageActive(page) && !PageUnevictable(page)) {
+- struct pagevec *pvec = &get_cpu_var(activate_page_pvecs);
++ struct pagevec *pvec = &get_locked_var(swapvec_lock,
++ activate_page_pvecs);
+
+ get_page(page);
+ if (!pagevec_add(pvec, page) || PageCompound(page))
+ pagevec_lru_move_fn(pvec, __activate_page, NULL);
+- put_cpu_var(activate_page_pvecs);
++ put_locked_var(swapvec_lock, activate_page_pvecs);
+ }
+ }
+
+@@ -326,7 +330,7 @@
+
+ static void __lru_cache_activate_page(struct page *page)
+ {
+- struct pagevec *pvec = &get_cpu_var(lru_add_pvec);
++ struct pagevec *pvec = &get_locked_var(swapvec_lock, lru_add_pvec);
+ int i;
+
+ /*
+@@ -348,7 +352,7 @@
+ }
+ }
+
+- put_cpu_var(lru_add_pvec);
++ put_locked_var(swapvec_lock, lru_add_pvec);
+ }
+
+ /*
+@@ -390,12 +394,12 @@
+
+ static void __lru_cache_add(struct page *page)
+ {
+- struct pagevec *pvec = &get_cpu_var(lru_add_pvec);
++ struct pagevec *pvec = &get_locked_var(swapvec_lock, lru_add_pvec);
+
+ get_page(page);
+ if (!pagevec_add(pvec, page) || PageCompound(page))
+ __pagevec_lru_add(pvec);
+- put_cpu_var(lru_add_pvec);
++ put_locked_var(swapvec_lock, lru_add_pvec);
+ }
+
+ /**
+@@ -593,9 +597,15 @@
+ unsigned long flags;
+
+ /* No harm done if a racing interrupt already did this */
+- local_irq_save(flags);
++#ifdef CONFIG_PREEMPT_RT_BASE
++ local_lock_irqsave_on(rotate_lock, flags, cpu);
+ pagevec_move_tail(pvec);
+- local_irq_restore(flags);
++ local_unlock_irqrestore_on(rotate_lock, flags, cpu);
++#else
++ local_lock_irqsave(rotate_lock, flags);
++ pagevec_move_tail(pvec);
++ local_unlock_irqrestore(rotate_lock, flags);
++#endif
+ }
+
+ pvec = &per_cpu(lru_deactivate_file_pvecs, cpu);
+@@ -627,11 +637,12 @@
+ return;
+
+ if (likely(get_page_unless_zero(page))) {
+- struct pagevec *pvec = &get_cpu_var(lru_deactivate_file_pvecs);
++ struct pagevec *pvec = &get_locked_var(swapvec_lock,
++ lru_deactivate_file_pvecs);
+
+ if (!pagevec_add(pvec, page) || PageCompound(page))
+ pagevec_lru_move_fn(pvec, lru_deactivate_file_fn, NULL);
+- put_cpu_var(lru_deactivate_file_pvecs);
++ put_locked_var(swapvec_lock, lru_deactivate_file_pvecs);
+ }
+ }
+
+@@ -646,27 +657,31 @@
+ void deactivate_page(struct page *page)
+ {
+ if (PageLRU(page) && PageActive(page) && !PageUnevictable(page)) {
+- struct pagevec *pvec = &get_cpu_var(lru_deactivate_pvecs);
++ struct pagevec *pvec = &get_locked_var(swapvec_lock,
++ lru_deactivate_pvecs);
+
+ get_page(page);
+ if (!pagevec_add(pvec, page) || PageCompound(page))
+ pagevec_lru_move_fn(pvec, lru_deactivate_fn, NULL);
+- put_cpu_var(lru_deactivate_pvecs);
++ put_locked_var(swapvec_lock, lru_deactivate_pvecs);
+ }
+ }
+
+ void lru_add_drain(void)
+ {
+- lru_add_drain_cpu(get_cpu());
+- put_cpu();
++ lru_add_drain_cpu(local_lock_cpu(swapvec_lock));
++ local_unlock_cpu(swapvec_lock);
+ }
+
+-static void lru_add_drain_per_cpu(struct work_struct *dummy)
++#ifdef CONFIG_PREEMPT_RT_BASE
++static inline void remote_lru_add_drain(int cpu, struct cpumask *has_work)
+ {
+- lru_add_drain();
++ local_lock_on(swapvec_lock, cpu);
++ lru_add_drain_cpu(cpu);
++ local_unlock_on(swapvec_lock, cpu);
+ }
+
+-static DEFINE_PER_CPU(struct work_struct, lru_add_drain_work);
++#else
+
+ /*
+ * lru_add_drain_wq is used to do lru_add_drain_all() from a WQ_MEM_RECLAIM
+@@ -686,6 +701,22 @@
+ }
+ early_initcall(lru_init);
+
++static void lru_add_drain_per_cpu(struct work_struct *dummy)
++{
++ lru_add_drain();
++}
++
++static DEFINE_PER_CPU(struct work_struct, lru_add_drain_work);
++static inline void remote_lru_add_drain(int cpu, struct cpumask *has_work)
++{
++ struct work_struct *work = &per_cpu(lru_add_drain_work, cpu);
++
++ INIT_WORK(work, lru_add_drain_per_cpu);
++ queue_work_on(cpu, lru_add_drain_wq, work);
++ cpumask_set_cpu(cpu, has_work);
++}
++#endif
++
+ void lru_add_drain_all(void)
+ {
+ static DEFINE_MUTEX(lock);
+@@ -697,21 +728,18 @@
+ cpumask_clear(&has_work);
+
+ for_each_online_cpu(cpu) {
+- struct work_struct *work = &per_cpu(lru_add_drain_work, cpu);
+-
+ if (pagevec_count(&per_cpu(lru_add_pvec, cpu)) ||
+ pagevec_count(&per_cpu(lru_rotate_pvecs, cpu)) ||
+ pagevec_count(&per_cpu(lru_deactivate_file_pvecs, cpu)) ||
+ pagevec_count(&per_cpu(lru_deactivate_pvecs, cpu)) ||
+- need_activate_page_drain(cpu)) {
+- INIT_WORK(work, lru_add_drain_per_cpu);
+- queue_work_on(cpu, lru_add_drain_wq, work);
+- cpumask_set_cpu(cpu, &has_work);
+- }
++ need_activate_page_drain(cpu))
++ remote_lru_add_drain(cpu, &has_work);
+ }
+
++#ifndef CONFIG_PREEMPT_RT_BASE
+ for_each_cpu(cpu, &has_work)
+ flush_work(&per_cpu(lru_add_drain_work, cpu));
++#endif
+
+ put_online_cpus();
+ mutex_unlock(&lock);
+diff -Nur linux-4.8.15.orig/mm/truncate.c linux-4.8.15/mm/truncate.c
+--- linux-4.8.15.orig/mm/truncate.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/mm/truncate.c 2017-01-01 17:07:16.115432374 +0100
+@@ -62,9 +62,12 @@
+ * protected by mapping->tree_lock.
+ */
+ if (!workingset_node_shadows(node) &&
+- !list_empty(&node->private_list))
+- list_lru_del(&workingset_shadow_nodes,
++ !list_empty(&node->private_list)) {
++ local_lock(workingset_shadow_lock);
++ list_lru_del(&__workingset_shadow_nodes,
+ &node->private_list);
++ local_unlock(workingset_shadow_lock);
++ }
+ __radix_tree_delete_node(&mapping->page_tree, node);
+ unlock:
+ spin_unlock_irq(&mapping->tree_lock);
+diff -Nur linux-4.8.15.orig/mm/vmalloc.c linux-4.8.15/mm/vmalloc.c
+--- linux-4.8.15.orig/mm/vmalloc.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/mm/vmalloc.c 2017-01-01 17:07:16.115432374 +0100
+@@ -845,7 +845,7 @@
+ struct vmap_block *vb;
+ struct vmap_area *va;
+ unsigned long vb_idx;
+- int node, err;
++ int node, err, cpu;
+ void *vaddr;
+
+ node = numa_node_id();
+@@ -888,11 +888,12 @@
+ BUG_ON(err);
+ radix_tree_preload_end();
+
+- vbq = &get_cpu_var(vmap_block_queue);
++ cpu = get_cpu_light();
++ vbq = this_cpu_ptr(&vmap_block_queue);
+ spin_lock(&vbq->lock);
+ list_add_tail_rcu(&vb->free_list, &vbq->free);
+ spin_unlock(&vbq->lock);
+- put_cpu_var(vmap_block_queue);
++ put_cpu_light();
+
+ return vaddr;
+ }
+@@ -961,6 +962,7 @@
+ struct vmap_block *vb;
+ void *vaddr = NULL;
+ unsigned int order;
++ int cpu;
+
+ BUG_ON(offset_in_page(size));
+ BUG_ON(size > PAGE_SIZE*VMAP_MAX_ALLOC);
+@@ -975,7 +977,8 @@
+ order = get_order(size);
+
+ rcu_read_lock();
+- vbq = &get_cpu_var(vmap_block_queue);
++ cpu = get_cpu_light();
++ vbq = this_cpu_ptr(&vmap_block_queue);
+ list_for_each_entry_rcu(vb, &vbq->free, free_list) {
+ unsigned long pages_off;
+
+@@ -998,7 +1001,7 @@
+ break;
+ }
+
+- put_cpu_var(vmap_block_queue);
++ put_cpu_light();
+ rcu_read_unlock();
+
+ /* Allocate new block if nothing was found */
+diff -Nur linux-4.8.15.orig/mm/vmstat.c linux-4.8.15/mm/vmstat.c
+--- linux-4.8.15.orig/mm/vmstat.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/mm/vmstat.c 2017-01-01 17:07:16.115432374 +0100
+@@ -245,6 +245,7 @@
+ long x;
+ long t;
+
++ preempt_disable_rt();
+ x = delta + __this_cpu_read(*p);
+
+ t = __this_cpu_read(pcp->stat_threshold);
+@@ -254,6 +255,7 @@
+ x = 0;
+ }
+ __this_cpu_write(*p, x);
++ preempt_enable_rt();
+ }
+ EXPORT_SYMBOL(__mod_zone_page_state);
+
+@@ -265,6 +267,7 @@
+ long x;
+ long t;
+
++ preempt_disable_rt();
+ x = delta + __this_cpu_read(*p);
+
+ t = __this_cpu_read(pcp->stat_threshold);
+@@ -274,6 +277,7 @@
+ x = 0;
+ }
+ __this_cpu_write(*p, x);
++ preempt_enable_rt();
+ }
+ EXPORT_SYMBOL(__mod_node_page_state);
+
+@@ -306,6 +310,7 @@
+ s8 __percpu *p = pcp->vm_stat_diff + item;
+ s8 v, t;
+
++ preempt_disable_rt();
+ v = __this_cpu_inc_return(*p);
+ t = __this_cpu_read(pcp->stat_threshold);
+ if (unlikely(v > t)) {
+@@ -314,6 +319,7 @@
+ zone_page_state_add(v + overstep, zone, item);
+ __this_cpu_write(*p, -overstep);
+ }
++ preempt_enable_rt();
+ }
+
+ void __inc_node_state(struct pglist_data *pgdat, enum node_stat_item item)
+@@ -322,6 +328,7 @@
+ s8 __percpu *p = pcp->vm_node_stat_diff + item;
+ s8 v, t;
+
++ preempt_disable_rt();
+ v = __this_cpu_inc_return(*p);
+ t = __this_cpu_read(pcp->stat_threshold);
+ if (unlikely(v > t)) {
+@@ -330,6 +337,7 @@
+ node_page_state_add(v + overstep, pgdat, item);
+ __this_cpu_write(*p, -overstep);
+ }
++ preempt_enable_rt();
+ }
+
+ void __inc_zone_page_state(struct page *page, enum zone_stat_item item)
+@@ -350,6 +358,7 @@
+ s8 __percpu *p = pcp->vm_stat_diff + item;
+ s8 v, t;
+
++ preempt_disable_rt();
+ v = __this_cpu_dec_return(*p);
+ t = __this_cpu_read(pcp->stat_threshold);
+ if (unlikely(v < - t)) {
+@@ -358,6 +367,7 @@
+ zone_page_state_add(v - overstep, zone, item);
+ __this_cpu_write(*p, overstep);
+ }
++ preempt_enable_rt();
+ }
+
+ void __dec_node_state(struct pglist_data *pgdat, enum node_stat_item item)
+@@ -366,6 +376,7 @@
+ s8 __percpu *p = pcp->vm_node_stat_diff + item;
+ s8 v, t;
+
++ preempt_disable_rt();
+ v = __this_cpu_dec_return(*p);
+ t = __this_cpu_read(pcp->stat_threshold);
+ if (unlikely(v < - t)) {
+@@ -374,6 +385,7 @@
+ node_page_state_add(v - overstep, pgdat, item);
+ __this_cpu_write(*p, overstep);
+ }
++ preempt_enable_rt();
+ }
+
+ void __dec_zone_page_state(struct page *page, enum zone_stat_item item)
+diff -Nur linux-4.8.15.orig/mm/workingset.c linux-4.8.15/mm/workingset.c
+--- linux-4.8.15.orig/mm/workingset.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/mm/workingset.c 2017-01-01 17:07:16.115432374 +0100
+@@ -334,7 +334,8 @@
+ * point where they would still be useful.
+ */
+
+-struct list_lru workingset_shadow_nodes;
++struct list_lru __workingset_shadow_nodes;
++DEFINE_LOCAL_IRQ_LOCK(workingset_shadow_lock);
+
+ static unsigned long count_shadow_nodes(struct shrinker *shrinker,
+ struct shrink_control *sc)
+@@ -344,9 +345,9 @@
+ unsigned long pages;
+
+ /* list_lru lock nests inside IRQ-safe mapping->tree_lock */
+- local_irq_disable();
+- shadow_nodes = list_lru_shrink_count(&workingset_shadow_nodes, sc);
+- local_irq_enable();
++ local_lock_irq(workingset_shadow_lock);
++ shadow_nodes = list_lru_shrink_count(&__workingset_shadow_nodes, sc);
++ local_unlock_irq(workingset_shadow_lock);
+
+ if (sc->memcg) {
+ pages = mem_cgroup_node_nr_lru_pages(sc->memcg, sc->nid,
+@@ -438,9 +439,9 @@
+ spin_unlock(&mapping->tree_lock);
+ ret = LRU_REMOVED_RETRY;
+ out:
+- local_irq_enable();
++ local_unlock_irq(workingset_shadow_lock);
+ cond_resched();
+- local_irq_disable();
++ local_lock_irq(workingset_shadow_lock);
+ spin_lock(lru_lock);
+ return ret;
+ }
+@@ -451,10 +452,10 @@
+ unsigned long ret;
+
+ /* list_lru lock nests inside IRQ-safe mapping->tree_lock */
+- local_irq_disable();
+- ret = list_lru_shrink_walk(&workingset_shadow_nodes, sc,
++ local_lock_irq(workingset_shadow_lock);
++ ret = list_lru_shrink_walk(&__workingset_shadow_nodes, sc,
+ shadow_lru_isolate, NULL);
+- local_irq_enable();
++ local_unlock_irq(workingset_shadow_lock);
+ return ret;
+ }
+
+@@ -492,7 +493,7 @@
+ pr_info("workingset: timestamp_bits=%d max_order=%d bucket_order=%u\n",
+ timestamp_bits, max_order, bucket_order);
+
+- ret = list_lru_init_key(&workingset_shadow_nodes, &shadow_nodes_key);
++ ret = list_lru_init_key(&__workingset_shadow_nodes, &shadow_nodes_key);
+ if (ret)
+ goto err;
+ ret = register_shrinker(&workingset_shadow_shrinker);
+@@ -500,7 +501,7 @@
+ goto err_list_lru;
+ return 0;
+ err_list_lru:
+- list_lru_destroy(&workingset_shadow_nodes);
++ list_lru_destroy(&__workingset_shadow_nodes);
+ err:
+ return ret;
+ }
+diff -Nur linux-4.8.15.orig/mm/zsmalloc.c linux-4.8.15/mm/zsmalloc.c
+--- linux-4.8.15.orig/mm/zsmalloc.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/mm/zsmalloc.c 2017-01-01 17:07:16.115432374 +0100
+@@ -53,6 +53,7 @@
+ #include <linux/mount.h>
+ #include <linux/migrate.h>
+ #include <linux/pagemap.h>
++#include <linux/locallock.h>
+
+ #define ZSPAGE_MAGIC 0x58
+
+@@ -70,9 +71,22 @@
+ */
+ #define ZS_MAX_ZSPAGE_ORDER 2
+ #define ZS_MAX_PAGES_PER_ZSPAGE (_AC(1, UL) << ZS_MAX_ZSPAGE_ORDER)
+-
+ #define ZS_HANDLE_SIZE (sizeof(unsigned long))
+
++#ifdef CONFIG_PREEMPT_RT_FULL
++
++struct zsmalloc_handle {
++ unsigned long addr;
++ struct mutex lock;
++};
++
++#define ZS_HANDLE_ALLOC_SIZE (sizeof(struct zsmalloc_handle))
++
++#else
++
++#define ZS_HANDLE_ALLOC_SIZE (sizeof(unsigned long))
++#endif
++
+ /*
+ * Object location (<PFN>, <obj_idx>) is encoded as
+ * as single (unsigned long) handle value.
+@@ -327,7 +341,7 @@
+
+ static int create_cache(struct zs_pool *pool)
+ {
+- pool->handle_cachep = kmem_cache_create("zs_handle", ZS_HANDLE_SIZE,
++ pool->handle_cachep = kmem_cache_create("zs_handle", ZS_HANDLE_ALLOC_SIZE,
+ 0, 0, NULL);
+ if (!pool->handle_cachep)
+ return 1;
+@@ -351,10 +365,27 @@
+
+ static unsigned long cache_alloc_handle(struct zs_pool *pool, gfp_t gfp)
+ {
+- return (unsigned long)kmem_cache_alloc(pool->handle_cachep,
+- gfp & ~(__GFP_HIGHMEM|__GFP_MOVABLE));
++ void *p;
++
++ p = kmem_cache_alloc(pool->handle_cachep,
++ gfp & ~(__GFP_HIGHMEM|__GFP_MOVABLE));
++#ifdef CONFIG_PREEMPT_RT_FULL
++ if (p) {
++ struct zsmalloc_handle *zh = p;
++
++ mutex_init(&zh->lock);
++ }
++#endif
++ return (unsigned long)p;
+ }
+
++#ifdef CONFIG_PREEMPT_RT_FULL
++static struct zsmalloc_handle *zs_get_pure_handle(unsigned long handle)
++{
++ return (void *)(handle &~((1 << OBJ_TAG_BITS) - 1));
++}
++#endif
++
+ static void cache_free_handle(struct zs_pool *pool, unsigned long handle)
+ {
+ kmem_cache_free(pool->handle_cachep, (void *)handle);
+@@ -373,12 +404,18 @@
+
+ static void record_obj(unsigned long handle, unsigned long obj)
+ {
++#ifdef CONFIG_PREEMPT_RT_FULL
++ struct zsmalloc_handle *zh = zs_get_pure_handle(handle);
++
++ WRITE_ONCE(zh->addr, obj);
++#else
+ /*
+ * lsb of @obj represents handle lock while other bits
+ * represent object value the handle is pointing so
+ * updating shouldn't do store tearing.
+ */
+ WRITE_ONCE(*(unsigned long *)handle, obj);
++#endif
+ }
+
+ /* zpool driver */
+@@ -467,6 +504,7 @@
+
+ /* per-cpu VM mapping areas for zspage accesses that cross page boundaries */
+ static DEFINE_PER_CPU(struct mapping_area, zs_map_area);
++static DEFINE_LOCAL_IRQ_LOCK(zs_map_area_lock);
+
+ static bool is_zspage_isolated(struct zspage *zspage)
+ {
+@@ -902,7 +940,13 @@
+
+ static unsigned long handle_to_obj(unsigned long handle)
+ {
++#ifdef CONFIG_PREEMPT_RT_FULL
++ struct zsmalloc_handle *zh = zs_get_pure_handle(handle);
++
++ return zh->addr;
++#else
+ return *(unsigned long *)handle;
++#endif
+ }
+
+ static unsigned long obj_to_head(struct page *page, void *obj)
+@@ -916,22 +960,46 @@
+
+ static inline int testpin_tag(unsigned long handle)
+ {
++#ifdef CONFIG_PREEMPT_RT_FULL
++ struct zsmalloc_handle *zh = zs_get_pure_handle(handle);
++
++ return mutex_is_locked(&zh->lock);
++#else
+ return bit_spin_is_locked(HANDLE_PIN_BIT, (unsigned long *)handle);
++#endif
+ }
+
+ static inline int trypin_tag(unsigned long handle)
+ {
++#ifdef CONFIG_PREEMPT_RT_FULL
++ struct zsmalloc_handle *zh = zs_get_pure_handle(handle);
++
++ return mutex_trylock(&zh->lock);
++#else
+ return bit_spin_trylock(HANDLE_PIN_BIT, (unsigned long *)handle);
++#endif
+ }
+
+ static void pin_tag(unsigned long handle)
+ {
++#ifdef CONFIG_PREEMPT_RT_FULL
++ struct zsmalloc_handle *zh = zs_get_pure_handle(handle);
++
++ return mutex_lock(&zh->lock);
++#else
+ bit_spin_lock(HANDLE_PIN_BIT, (unsigned long *)handle);
++#endif
+ }
+
+ static void unpin_tag(unsigned long handle)
+ {
++#ifdef CONFIG_PREEMPT_RT_FULL
++ struct zsmalloc_handle *zh = zs_get_pure_handle(handle);
++
++ return mutex_unlock(&zh->lock);
++#else
+ bit_spin_unlock(HANDLE_PIN_BIT, (unsigned long *)handle);
++#endif
+ }
+
+ static void reset_page(struct page *page)
+@@ -1423,7 +1491,7 @@
+ class = pool->size_class[class_idx];
+ off = (class->size * obj_idx) & ~PAGE_MASK;
+
+- area = &get_cpu_var(zs_map_area);
++ area = &get_locked_var(zs_map_area_lock, zs_map_area);
+ area->vm_mm = mm;
+ if (off + class->size <= PAGE_SIZE) {
+ /* this object is contained entirely within a page */
+@@ -1477,7 +1545,7 @@
+
+ __zs_unmap_object(area, pages, off, class->size);
+ }
+- put_cpu_var(zs_map_area);
++ put_locked_var(zs_map_area_lock, zs_map_area);
+
+ migrate_read_unlock(zspage);
+ unpin_tag(handle);
+diff -Nur linux-4.8.15.orig/net/core/dev.c linux-4.8.15/net/core/dev.c
+--- linux-4.8.15.orig/net/core/dev.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/net/core/dev.c 2017-01-01 17:07:16.119432629 +0100
+@@ -190,6 +190,7 @@
+ static DEFINE_READ_MOSTLY_HASHTABLE(napi_hash, 8);
+
+ static seqcount_t devnet_rename_seq;
++static DEFINE_MUTEX(devnet_rename_mutex);
+
+ static inline void dev_base_seq_inc(struct net *net)
+ {
+@@ -211,14 +212,14 @@
+ static inline void rps_lock(struct softnet_data *sd)
+ {
+ #ifdef CONFIG_RPS
+- spin_lock(&sd->input_pkt_queue.lock);
++ raw_spin_lock(&sd->input_pkt_queue.raw_lock);
+ #endif
+ }
+
+ static inline void rps_unlock(struct softnet_data *sd)
+ {
+ #ifdef CONFIG_RPS
+- spin_unlock(&sd->input_pkt_queue.lock);
++ raw_spin_unlock(&sd->input_pkt_queue.raw_lock);
+ #endif
+ }
+
+@@ -888,7 +889,8 @@
+ strcpy(name, dev->name);
+ rcu_read_unlock();
+ if (read_seqcount_retry(&devnet_rename_seq, seq)) {
+- cond_resched();
++ mutex_lock(&devnet_rename_mutex);
++ mutex_unlock(&devnet_rename_mutex);
+ goto retry;
+ }
+
+@@ -1157,20 +1159,17 @@
+ if (dev->flags & IFF_UP)
+ return -EBUSY;
+
+- write_seqcount_begin(&devnet_rename_seq);
++ mutex_lock(&devnet_rename_mutex);
++ __raw_write_seqcount_begin(&devnet_rename_seq);
+
+- if (strncmp(newname, dev->name, IFNAMSIZ) == 0) {
+- write_seqcount_end(&devnet_rename_seq);
+- return 0;
+- }
++ if (strncmp(newname, dev->name, IFNAMSIZ) == 0)
++ goto outunlock;
+
+ memcpy(oldname, dev->name, IFNAMSIZ);
+
+ err = dev_get_valid_name(net, dev, newname);
+- if (err < 0) {
+- write_seqcount_end(&devnet_rename_seq);
+- return err;
+- }
++ if (err < 0)
++ goto outunlock;
+
+ if (oldname[0] && !strchr(oldname, '%'))
+ netdev_info(dev, "renamed from %s\n", oldname);
+@@ -1183,11 +1182,12 @@
+ if (ret) {
+ memcpy(dev->name, oldname, IFNAMSIZ);
+ dev->name_assign_type = old_assign_type;
+- write_seqcount_end(&devnet_rename_seq);
+- return ret;
++ err = ret;
++ goto outunlock;
+ }
+
+- write_seqcount_end(&devnet_rename_seq);
++ __raw_write_seqcount_end(&devnet_rename_seq);
++ mutex_unlock(&devnet_rename_mutex);
+
+ netdev_adjacent_rename_links(dev, oldname);
+
+@@ -1208,7 +1208,8 @@
+ /* err >= 0 after dev_alloc_name() or stores the first errno */
+ if (err >= 0) {
+ err = ret;
+- write_seqcount_begin(&devnet_rename_seq);
++ mutex_lock(&devnet_rename_mutex);
++ __raw_write_seqcount_begin(&devnet_rename_seq);
+ memcpy(dev->name, oldname, IFNAMSIZ);
+ memcpy(oldname, newname, IFNAMSIZ);
+ dev->name_assign_type = old_assign_type;
+@@ -1221,6 +1222,11 @@
+ }
+
+ return err;
++
++outunlock:
++ __raw_write_seqcount_end(&devnet_rename_seq);
++ mutex_unlock(&devnet_rename_mutex);
++ return err;
+ }
+
+ /**
+@@ -2268,6 +2274,7 @@
+ sd->output_queue_tailp = &q->next_sched;
+ raise_softirq_irqoff(NET_TX_SOFTIRQ);
+ local_irq_restore(flags);
++ preempt_check_resched_rt();
+ }
+
+ void __netif_schedule(struct Qdisc *q)
+@@ -2349,6 +2356,7 @@
+ __this_cpu_write(softnet_data.completion_queue, skb);
+ raise_softirq_irqoff(NET_TX_SOFTIRQ);
+ local_irq_restore(flags);
++ preempt_check_resched_rt();
+ }
+ EXPORT_SYMBOL(__dev_kfree_skb_irq);
+
+@@ -3083,7 +3091,11 @@
+ * This permits qdisc->running owner to get the lock more
+ * often and dequeue packets faster.
+ */
++#ifdef CONFIG_PREEMPT_RT_FULL
++ contended = true;
++#else
+ contended = qdisc_is_running(q);
++#endif
+ if (unlikely(contended))
+ spin_lock(&q->busylock);
+
+@@ -3146,8 +3158,10 @@
+ #define skb_update_prio(skb)
+ #endif
+
++#ifndef CONFIG_PREEMPT_RT_FULL
+ DEFINE_PER_CPU(int, xmit_recursion);
+ EXPORT_SYMBOL(xmit_recursion);
++#endif
+
+ /**
+ * dev_loopback_xmit - loop back @skb
+@@ -3391,8 +3405,7 @@
+ int cpu = smp_processor_id(); /* ok because BHs are off */
+
+ if (txq->xmit_lock_owner != cpu) {
+- if (unlikely(__this_cpu_read(xmit_recursion) >
+- XMIT_RECURSION_LIMIT))
++ if (unlikely(xmit_rec_read() > XMIT_RECURSION_LIMIT))
+ goto recursion_alert;
+
+ skb = validate_xmit_skb(skb, dev);
+@@ -3402,9 +3415,9 @@
+ HARD_TX_LOCK(dev, txq, cpu);
+
+ if (!netif_xmit_stopped(txq)) {
+- __this_cpu_inc(xmit_recursion);
++ xmit_rec_inc();
+ skb = dev_hard_start_xmit(skb, dev, txq, &rc);
+- __this_cpu_dec(xmit_recursion);
++ xmit_rec_dec();
+ if (dev_xmit_complete(rc)) {
+ HARD_TX_UNLOCK(dev, txq);
+ goto out;
+@@ -3778,6 +3791,7 @@
+ rps_unlock(sd);
+
+ local_irq_restore(flags);
++ preempt_check_resched_rt();
+
+ atomic_long_inc(&skb->dev->rx_dropped);
+ kfree_skb(skb);
+@@ -3796,7 +3810,7 @@
+ struct rps_dev_flow voidflow, *rflow = &voidflow;
+ int cpu;
+
+- preempt_disable();
++ migrate_disable();
+ rcu_read_lock();
+
+ cpu = get_rps_cpu(skb->dev, skb, &rflow);
+@@ -3806,13 +3820,13 @@
+ ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
+
+ rcu_read_unlock();
+- preempt_enable();
++ migrate_enable();
+ } else
+ #endif
+ {
+ unsigned int qtail;
+- ret = enqueue_to_backlog(skb, get_cpu(), &qtail);
+- put_cpu();
++ ret = enqueue_to_backlog(skb, get_cpu_light(), &qtail);
++ put_cpu_light();
+ }
+ return ret;
+ }
+@@ -3846,11 +3860,9 @@
+
+ trace_netif_rx_ni_entry(skb);
+
+- preempt_disable();
++ local_bh_disable();
+ err = netif_rx_internal(skb);
+- if (local_softirq_pending())
+- do_softirq();
+- preempt_enable();
++ local_bh_enable();
+
+ return err;
+ }
+@@ -4322,7 +4334,7 @@
+ skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) {
+ if (skb->dev == dev) {
+ __skb_unlink(skb, &sd->input_pkt_queue);
+- kfree_skb(skb);
++ __skb_queue_tail(&sd->tofree_queue, skb);
+ input_queue_head_incr(sd);
+ }
+ }
+@@ -4331,10 +4343,13 @@
+ skb_queue_walk_safe(&sd->process_queue, skb, tmp) {
+ if (skb->dev == dev) {
+ __skb_unlink(skb, &sd->process_queue);
+- kfree_skb(skb);
++ __skb_queue_tail(&sd->tofree_queue, skb);
+ input_queue_head_incr(sd);
+ }
+ }
++
++ if (!skb_queue_empty(&sd->tofree_queue))
++ raise_softirq_irqoff(NET_RX_SOFTIRQ);
+ }
+
+ static int napi_gro_complete(struct sk_buff *skb)
+@@ -4797,6 +4812,7 @@
+ sd->rps_ipi_list = NULL;
+
+ local_irq_enable();
++ preempt_check_resched_rt();
+
+ /* Send pending IPI's to kick RPS processing on remote cpus. */
+ while (remsd) {
+@@ -4810,6 +4826,7 @@
+ } else
+ #endif
+ local_irq_enable();
++ preempt_check_resched_rt();
+ }
+
+ static bool sd_has_rps_ipi_waiting(struct softnet_data *sd)
+@@ -4891,9 +4908,11 @@
+ local_irq_save(flags);
+ ____napi_schedule(this_cpu_ptr(&softnet_data), n);
+ local_irq_restore(flags);
++ preempt_check_resched_rt();
+ }
+ EXPORT_SYMBOL(__napi_schedule);
+
++#ifndef CONFIG_PREEMPT_RT_FULL
+ /**
+ * __napi_schedule_irqoff - schedule for receive
+ * @n: entry to schedule
+@@ -4905,6 +4924,7 @@
+ ____napi_schedule(this_cpu_ptr(&softnet_data), n);
+ }
+ EXPORT_SYMBOL(__napi_schedule_irqoff);
++#endif
+
+ void __napi_complete(struct napi_struct *n)
+ {
+@@ -5194,13 +5214,21 @@
+ struct softnet_data *sd = this_cpu_ptr(&softnet_data);
+ unsigned long time_limit = jiffies + 2;
+ int budget = netdev_budget;
++ struct sk_buff_head tofree_q;
++ struct sk_buff *skb;
+ LIST_HEAD(list);
+ LIST_HEAD(repoll);
+
++ __skb_queue_head_init(&tofree_q);
++
+ local_irq_disable();
++ skb_queue_splice_init(&sd->tofree_queue, &tofree_q);
+ list_splice_init(&sd->poll_list, &list);
+ local_irq_enable();
+
++ while ((skb = __skb_dequeue(&tofree_q)))
++ kfree_skb(skb);
++
+ for (;;) {
+ struct napi_struct *n;
+
+@@ -5231,7 +5259,7 @@
+ list_splice_tail(&repoll, &list);
+ list_splice(&list, &sd->poll_list);
+ if (!list_empty(&sd->poll_list))
+- __raise_softirq_irqoff(NET_RX_SOFTIRQ);
++ __raise_softirq_irqoff_ksoft(NET_RX_SOFTIRQ);
+
+ net_rps_action_and_irq_enable(sd);
+ }
+@@ -7989,16 +8017,20 @@
+
+ raise_softirq_irqoff(NET_TX_SOFTIRQ);
+ local_irq_enable();
++ preempt_check_resched_rt();
+
+ /* Process offline CPU's input_pkt_queue */
+ while ((skb = __skb_dequeue(&oldsd->process_queue))) {
+ netif_rx_ni(skb);
+ input_queue_head_incr(oldsd);
+ }
+- while ((skb = skb_dequeue(&oldsd->input_pkt_queue))) {
++ while ((skb = __skb_dequeue(&oldsd->input_pkt_queue))) {
+ netif_rx_ni(skb);
+ input_queue_head_incr(oldsd);
+ }
++ while ((skb = __skb_dequeue(&oldsd->tofree_queue))) {
++ kfree_skb(skb);
++ }
+
+ return NOTIFY_OK;
+ }
+@@ -8300,8 +8332,9 @@
+ for_each_possible_cpu(i) {
+ struct softnet_data *sd = &per_cpu(softnet_data, i);
+
+- skb_queue_head_init(&sd->input_pkt_queue);
+- skb_queue_head_init(&sd->process_queue);
++ skb_queue_head_init_raw(&sd->input_pkt_queue);
++ skb_queue_head_init_raw(&sd->process_queue);
++ skb_queue_head_init_raw(&sd->tofree_queue);
+ INIT_LIST_HEAD(&sd->poll_list);
+ sd->output_queue_tailp = &sd->output_queue;
+ #ifdef CONFIG_RPS
+diff -Nur linux-4.8.15.orig/net/core/filter.c linux-4.8.15/net/core/filter.c
+--- linux-4.8.15.orig/net/core/filter.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/net/core/filter.c 2017-01-01 17:07:16.119432629 +0100
+@@ -1592,7 +1592,7 @@
+ {
+ int ret;
+
+- if (unlikely(__this_cpu_read(xmit_recursion) > XMIT_RECURSION_LIMIT)) {
++ if (unlikely(xmit_rec_read() > XMIT_RECURSION_LIMIT)) {
+ net_crit_ratelimited("bpf: recursion limit reached on datapath, buggy bpf program?\n");
+ kfree_skb(skb);
+ return -ENETDOWN;
+@@ -1600,9 +1600,9 @@
+
+ skb->dev = dev;
+
+- __this_cpu_inc(xmit_recursion);
++ xmit_rec_inc();
+ ret = dev_queue_xmit(skb);
+- __this_cpu_dec(xmit_recursion);
++ xmit_rec_dec();
+
+ return ret;
+ }
+diff -Nur linux-4.8.15.orig/net/core/gen_estimator.c linux-4.8.15/net/core/gen_estimator.c
+--- linux-4.8.15.orig/net/core/gen_estimator.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/net/core/gen_estimator.c 2017-01-01 17:07:16.119432629 +0100
+@@ -84,7 +84,7 @@
+ struct gnet_stats_basic_packed *bstats;
+ struct gnet_stats_rate_est64 *rate_est;
+ spinlock_t *stats_lock;
+- seqcount_t *running;
++ net_seqlock_t *running;
+ int ewma_log;
+ u32 last_packets;
+ unsigned long avpps;
+@@ -213,7 +213,7 @@
+ struct gnet_stats_basic_cpu __percpu *cpu_bstats,
+ struct gnet_stats_rate_est64 *rate_est,
+ spinlock_t *stats_lock,
+- seqcount_t *running,
++ net_seqlock_t *running,
+ struct nlattr *opt)
+ {
+ struct gen_estimator *est;
+@@ -309,7 +309,7 @@
+ struct gnet_stats_basic_cpu __percpu *cpu_bstats,
+ struct gnet_stats_rate_est64 *rate_est,
+ spinlock_t *stats_lock,
+- seqcount_t *running, struct nlattr *opt)
++ net_seqlock_t *running, struct nlattr *opt)
+ {
+ gen_kill_estimator(bstats, rate_est);
+ return gen_new_estimator(bstats, cpu_bstats, rate_est, stats_lock, running, opt);
+diff -Nur linux-4.8.15.orig/net/core/gen_stats.c linux-4.8.15/net/core/gen_stats.c
+--- linux-4.8.15.orig/net/core/gen_stats.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/net/core/gen_stats.c 2017-01-01 17:07:16.119432629 +0100
+@@ -130,7 +130,7 @@
+ }
+
+ void
+-__gnet_stats_copy_basic(const seqcount_t *running,
++__gnet_stats_copy_basic(net_seqlock_t *running,
+ struct gnet_stats_basic_packed *bstats,
+ struct gnet_stats_basic_cpu __percpu *cpu,
+ struct gnet_stats_basic_packed *b)
+@@ -143,10 +143,10 @@
+ }
+ do {
+ if (running)
+- seq = read_seqcount_begin(running);
++ seq = net_seq_begin(running);
+ bstats->bytes = b->bytes;
+ bstats->packets = b->packets;
+- } while (running && read_seqcount_retry(running, seq));
++ } while (running && net_seq_retry(running, seq));
+ }
+ EXPORT_SYMBOL(__gnet_stats_copy_basic);
+
+@@ -164,7 +164,7 @@
+ * if the room in the socket buffer was not sufficient.
+ */
+ int
+-gnet_stats_copy_basic(const seqcount_t *running,
++gnet_stats_copy_basic(net_seqlock_t *running,
+ struct gnet_dump *d,
+ struct gnet_stats_basic_cpu __percpu *cpu,
+ struct gnet_stats_basic_packed *b)
+diff -Nur linux-4.8.15.orig/net/core/skbuff.c linux-4.8.15/net/core/skbuff.c
+--- linux-4.8.15.orig/net/core/skbuff.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/net/core/skbuff.c 2017-01-01 17:07:16.123432884 +0100
+@@ -64,6 +64,7 @@
+ #include <linux/errqueue.h>
+ #include <linux/prefetch.h>
+ #include <linux/if_vlan.h>
++#include <linux/locallock.h>
+
+ #include <net/protocol.h>
+ #include <net/dst.h>
+@@ -360,6 +361,8 @@
+
+ static DEFINE_PER_CPU(struct page_frag_cache, netdev_alloc_cache);
+ static DEFINE_PER_CPU(struct napi_alloc_cache, napi_alloc_cache);
++static DEFINE_LOCAL_IRQ_LOCK(netdev_alloc_lock);
++static DEFINE_LOCAL_IRQ_LOCK(napi_alloc_cache_lock);
+
+ static void *__netdev_alloc_frag(unsigned int fragsz, gfp_t gfp_mask)
+ {
+@@ -367,10 +370,10 @@
+ unsigned long flags;
+ void *data;
+
+- local_irq_save(flags);
++ local_lock_irqsave(netdev_alloc_lock, flags);
+ nc = this_cpu_ptr(&netdev_alloc_cache);
+ data = __alloc_page_frag(nc, fragsz, gfp_mask);
+- local_irq_restore(flags);
++ local_unlock_irqrestore(netdev_alloc_lock, flags);
+ return data;
+ }
+
+@@ -389,9 +392,13 @@
+
+ static void *__napi_alloc_frag(unsigned int fragsz, gfp_t gfp_mask)
+ {
+- struct napi_alloc_cache *nc = this_cpu_ptr(&napi_alloc_cache);
++ struct napi_alloc_cache *nc;
++ void *data;
+
+- return __alloc_page_frag(&nc->page, fragsz, gfp_mask);
++ nc = &get_locked_var(napi_alloc_cache_lock, napi_alloc_cache);
++ data = __alloc_page_frag(&nc->page, fragsz, gfp_mask);
++ put_locked_var(napi_alloc_cache_lock, napi_alloc_cache);
++ return data;
+ }
+
+ void *napi_alloc_frag(unsigned int fragsz)
+@@ -438,13 +445,13 @@
+ if (sk_memalloc_socks())
+ gfp_mask |= __GFP_MEMALLOC;
+
+- local_irq_save(flags);
++ local_lock_irqsave(netdev_alloc_lock, flags);
+
+ nc = this_cpu_ptr(&netdev_alloc_cache);
+ data = __alloc_page_frag(nc, len, gfp_mask);
+ pfmemalloc = nc->pfmemalloc;
+
+- local_irq_restore(flags);
++ local_unlock_irqrestore(netdev_alloc_lock, flags);
+
+ if (unlikely(!data))
+ return NULL;
+@@ -485,9 +492,10 @@
+ struct sk_buff *__napi_alloc_skb(struct napi_struct *napi, unsigned int len,
+ gfp_t gfp_mask)
+ {
+- struct napi_alloc_cache *nc = this_cpu_ptr(&napi_alloc_cache);
++ struct napi_alloc_cache *nc;
+ struct sk_buff *skb;
+ void *data;
++ bool pfmemalloc;
+
+ len += NET_SKB_PAD + NET_IP_ALIGN;
+
+@@ -505,7 +513,10 @@
+ if (sk_memalloc_socks())
+ gfp_mask |= __GFP_MEMALLOC;
+
++ nc = &get_locked_var(napi_alloc_cache_lock, napi_alloc_cache);
+ data = __alloc_page_frag(&nc->page, len, gfp_mask);
++ pfmemalloc = nc->page.pfmemalloc;
++ put_locked_var(napi_alloc_cache_lock, napi_alloc_cache);
+ if (unlikely(!data))
+ return NULL;
+
+@@ -516,7 +527,7 @@
+ }
+
+ /* use OR instead of assignment to avoid clearing of bits in mask */
+- if (nc->page.pfmemalloc)
++ if (pfmemalloc)
+ skb->pfmemalloc = 1;
+ skb->head_frag = 1;
+
+@@ -760,23 +771,26 @@
+
+ void __kfree_skb_flush(void)
+ {
+- struct napi_alloc_cache *nc = this_cpu_ptr(&napi_alloc_cache);
++ struct napi_alloc_cache *nc;
+
++ nc = &get_locked_var(napi_alloc_cache_lock, napi_alloc_cache);
+ /* flush skb_cache if containing objects */
+ if (nc->skb_count) {
+ kmem_cache_free_bulk(skbuff_head_cache, nc->skb_count,
+ nc->skb_cache);
+ nc->skb_count = 0;
+ }
++ put_locked_var(napi_alloc_cache_lock, napi_alloc_cache);
+ }
+
+ static inline void _kfree_skb_defer(struct sk_buff *skb)
+ {
+- struct napi_alloc_cache *nc = this_cpu_ptr(&napi_alloc_cache);
++ struct napi_alloc_cache *nc;
+
+ /* drop skb->head and call any destructors for packet */
+ skb_release_all(skb);
+
++ nc = &get_locked_var(napi_alloc_cache_lock, napi_alloc_cache);
+ /* record skb to CPU local list */
+ nc->skb_cache[nc->skb_count++] = skb;
+
+@@ -791,6 +805,7 @@
+ nc->skb_cache);
+ nc->skb_count = 0;
+ }
++ put_locked_var(napi_alloc_cache_lock, napi_alloc_cache);
+ }
+ void __kfree_skb_defer(struct sk_buff *skb)
+ {
+diff -Nur linux-4.8.15.orig/net/core/sock.c linux-4.8.15/net/core/sock.c
+--- linux-4.8.15.orig/net/core/sock.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/net/core/sock.c 2017-01-01 17:07:16.123432884 +0100
+@@ -2510,12 +2510,11 @@
+ if (sk->sk_lock.owned)
+ __lock_sock(sk);
+ sk->sk_lock.owned = 1;
+- spin_unlock(&sk->sk_lock.slock);
++ spin_unlock_bh(&sk->sk_lock.slock);
+ /*
+ * The sk_lock has mutex_lock() semantics here:
+ */
+ mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
+- local_bh_enable();
+ }
+ EXPORT_SYMBOL(lock_sock_nested);
+
+diff -Nur linux-4.8.15.orig/net/ipv4/icmp.c linux-4.8.15/net/ipv4/icmp.c
+--- linux-4.8.15.orig/net/ipv4/icmp.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/net/ipv4/icmp.c 2017-01-01 17:07:16.123432884 +0100
+@@ -69,6 +69,7 @@
+ #include <linux/jiffies.h>
+ #include <linux/kernel.h>
+ #include <linux/fcntl.h>
++#include <linux/sysrq.h>
+ #include <linux/socket.h>
+ #include <linux/in.h>
+ #include <linux/inet.h>
+@@ -77,6 +78,7 @@
+ #include <linux/string.h>
+ #include <linux/netfilter_ipv4.h>
+ #include <linux/slab.h>
++#include <linux/locallock.h>
+ #include <net/snmp.h>
+ #include <net/ip.h>
+ #include <net/route.h>
+@@ -204,6 +206,8 @@
+ *
+ * On SMP we have one ICMP socket per-cpu.
+ */
++static DEFINE_LOCAL_IRQ_LOCK(icmp_sk_lock);
++
+ static struct sock *icmp_sk(struct net *net)
+ {
+ return *this_cpu_ptr(net->ipv4.icmp_sk);
+@@ -215,12 +219,14 @@
+
+ local_bh_disable();
+
++ local_lock(icmp_sk_lock);
+ sk = icmp_sk(net);
+
+ if (unlikely(!spin_trylock(&sk->sk_lock.slock))) {
+ /* This can happen if the output path signals a
+ * dst_link_failure() for an outgoing ICMP packet.
+ */
++ local_unlock(icmp_sk_lock);
+ local_bh_enable();
+ return NULL;
+ }
+@@ -230,6 +236,7 @@
+ static inline void icmp_xmit_unlock(struct sock *sk)
+ {
+ spin_unlock_bh(&sk->sk_lock.slock);
++ local_unlock(icmp_sk_lock);
+ }
+
+ int sysctl_icmp_msgs_per_sec __read_mostly = 1000;
+@@ -358,6 +365,7 @@
+ struct sock *sk;
+ struct sk_buff *skb;
+
++ local_lock(icmp_sk_lock);
+ sk = icmp_sk(dev_net((*rt)->dst.dev));
+ if (ip_append_data(sk, fl4, icmp_glue_bits, icmp_param,
+ icmp_param->data_len+icmp_param->head_len,
+@@ -380,6 +388,7 @@
+ skb->ip_summed = CHECKSUM_NONE;
+ ip_push_pending_frames(sk, fl4);
+ }
++ local_unlock(icmp_sk_lock);
+ }
+
+ /*
+@@ -891,6 +900,30 @@
+ }
+
+ /*
++ * 32bit and 64bit have different timestamp length, so we check for
++ * the cookie at offset 20 and verify it is repeated at offset 50
++ */
++#define CO_POS0 20
++#define CO_POS1 50
++#define CO_SIZE sizeof(int)
++#define ICMP_SYSRQ_SIZE 57
++
++/*
++ * We got a ICMP_SYSRQ_SIZE sized ping request. Check for the cookie
++ * pattern and if it matches send the next byte as a trigger to sysrq.
++ */
++static void icmp_check_sysrq(struct net *net, struct sk_buff *skb)
++{
++ int cookie = htonl(net->ipv4.sysctl_icmp_echo_sysrq);
++ char *p = skb->data;
++
++ if (!memcmp(&cookie, p + CO_POS0, CO_SIZE) &&
++ !memcmp(&cookie, p + CO_POS1, CO_SIZE) &&
++ p[CO_POS0 + CO_SIZE] == p[CO_POS1 + CO_SIZE])
++ handle_sysrq(p[CO_POS0 + CO_SIZE]);
++}
++
++/*
+ * Handle ICMP_ECHO ("ping") requests.
+ *
+ * RFC 1122: 3.2.2.6 MUST have an echo server that answers ICMP echo
+@@ -917,6 +950,11 @@
+ icmp_param.data_len = skb->len;
+ icmp_param.head_len = sizeof(struct icmphdr);
+ icmp_reply(&icmp_param, skb);
++
++ if (skb->len == ICMP_SYSRQ_SIZE &&
++ net->ipv4.sysctl_icmp_echo_sysrq) {
++ icmp_check_sysrq(net, skb);
++ }
+ }
+ /* should there be an ICMP stat for ignored echos? */
+ return true;
+diff -Nur linux-4.8.15.orig/net/ipv4/sysctl_net_ipv4.c linux-4.8.15/net/ipv4/sysctl_net_ipv4.c
+--- linux-4.8.15.orig/net/ipv4/sysctl_net_ipv4.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/net/ipv4/sysctl_net_ipv4.c 2017-01-01 17:07:16.123432884 +0100
+@@ -681,6 +681,13 @@
+ .proc_handler = proc_dointvec
+ },
+ {
++ .procname = "icmp_echo_sysrq",
++ .data = &init_net.ipv4.sysctl_icmp_echo_sysrq,
++ .maxlen = sizeof(int),
++ .mode = 0644,
++ .proc_handler = proc_dointvec
++ },
++ {
+ .procname = "icmp_ignore_bogus_error_responses",
+ .data = &init_net.ipv4.sysctl_icmp_ignore_bogus_error_responses,
+ .maxlen = sizeof(int),
+diff -Nur linux-4.8.15.orig/net/ipv4/tcp_ipv4.c linux-4.8.15/net/ipv4/tcp_ipv4.c
+--- linux-4.8.15.orig/net/ipv4/tcp_ipv4.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/net/ipv4/tcp_ipv4.c 2017-01-01 17:07:16.127433142 +0100
+@@ -62,6 +62,7 @@
+ #include <linux/init.h>
+ #include <linux/times.h>
+ #include <linux/slab.h>
++#include <linux/locallock.h>
+
+ #include <net/net_namespace.h>
+ #include <net/icmp.h>
+@@ -565,6 +566,7 @@
+ }
+ EXPORT_SYMBOL(tcp_v4_send_check);
+
++static DEFINE_LOCAL_IRQ_LOCK(tcp_sk_lock);
+ /*
+ * This routine will send an RST to the other tcp.
+ *
+@@ -692,6 +694,8 @@
+ offsetof(struct inet_timewait_sock, tw_bound_dev_if));
+
+ arg.tos = ip_hdr(skb)->tos;
++
++ local_lock(tcp_sk_lock);
+ local_bh_disable();
+ ip_send_unicast_reply(*this_cpu_ptr(net->ipv4.tcp_sk),
+ skb, &TCP_SKB_CB(skb)->header.h4.opt,
+@@ -701,6 +705,7 @@
+ __TCP_INC_STATS(net, TCP_MIB_OUTSEGS);
+ __TCP_INC_STATS(net, TCP_MIB_OUTRSTS);
+ local_bh_enable();
++ local_unlock(tcp_sk_lock);
+
+ #ifdef CONFIG_TCP_MD5SIG
+ out:
+@@ -776,6 +781,7 @@
+ if (oif)
+ arg.bound_dev_if = oif;
+ arg.tos = tos;
++ local_lock(tcp_sk_lock);
+ local_bh_disable();
+ ip_send_unicast_reply(*this_cpu_ptr(net->ipv4.tcp_sk),
+ skb, &TCP_SKB_CB(skb)->header.h4.opt,
+@@ -784,6 +790,7 @@
+
+ __TCP_INC_STATS(net, TCP_MIB_OUTSEGS);
+ local_bh_enable();
++ local_unlock(tcp_sk_lock);
+ }
+
+ static void tcp_v4_timewait_ack(struct sock *sk, struct sk_buff *skb)
+diff -Nur linux-4.8.15.orig/net/mac80211/rx.c linux-4.8.15/net/mac80211/rx.c
+--- linux-4.8.15.orig/net/mac80211/rx.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/net/mac80211/rx.c 2017-01-01 17:07:16.127433142 +0100
+@@ -4070,7 +4070,7 @@
+ struct ieee80211_supported_band *sband;
+ struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
+
+- WARN_ON_ONCE(softirq_count() == 0);
++ WARN_ON_ONCE_NONRT(softirq_count() == 0);
+
+ if (WARN_ON(status->band >= NUM_NL80211_BANDS))
+ goto drop;
+diff -Nur linux-4.8.15.orig/net/netfilter/core.c linux-4.8.15/net/netfilter/core.c
+--- linux-4.8.15.orig/net/netfilter/core.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/net/netfilter/core.c 2017-01-01 17:07:16.127433142 +0100
+@@ -22,11 +22,17 @@
+ #include <linux/proc_fs.h>
+ #include <linux/mutex.h>
+ #include <linux/slab.h>
++#include <linux/locallock.h>
+ #include <net/net_namespace.h>
+ #include <net/sock.h>
+
+ #include "nf_internals.h"
+
++#ifdef CONFIG_PREEMPT_RT_BASE
++DEFINE_LOCAL_IRQ_LOCK(xt_write_lock);
++EXPORT_PER_CPU_SYMBOL(xt_write_lock);
++#endif
++
+ static DEFINE_MUTEX(afinfo_mutex);
+
+ const struct nf_afinfo __rcu *nf_afinfo[NFPROTO_NUMPROTO] __read_mostly;
+diff -Nur linux-4.8.15.orig/net/packet/af_packet.c linux-4.8.15/net/packet/af_packet.c
+--- linux-4.8.15.orig/net/packet/af_packet.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/net/packet/af_packet.c 2017-01-01 17:07:16.131433400 +0100
+@@ -63,6 +63,7 @@
+ #include <linux/if_packet.h>
+ #include <linux/wireless.h>
+ #include <linux/kernel.h>
++#include <linux/delay.h>
+ #include <linux/kmod.h>
+ #include <linux/slab.h>
+ #include <linux/vmalloc.h>
+@@ -694,7 +695,7 @@
+ if (BLOCK_NUM_PKTS(pbd)) {
+ while (atomic_read(&pkc->blk_fill_in_prog)) {
+ /* Waiting for skb_copy_bits to finish... */
+- cpu_relax();
++ cpu_chill();
+ }
+ }
+
+@@ -956,7 +957,7 @@
+ if (!(status & TP_STATUS_BLK_TMO)) {
+ while (atomic_read(&pkc->blk_fill_in_prog)) {
+ /* Waiting for skb_copy_bits to finish... */
+- cpu_relax();
++ cpu_chill();
+ }
+ }
+ prb_close_block(pkc, pbd, po, status);
+diff -Nur linux-4.8.15.orig/net/rds/ib_rdma.c linux-4.8.15/net/rds/ib_rdma.c
+--- linux-4.8.15.orig/net/rds/ib_rdma.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/net/rds/ib_rdma.c 2017-01-01 17:07:16.131433400 +0100
+@@ -34,6 +34,7 @@
+ #include <linux/slab.h>
+ #include <linux/rculist.h>
+ #include <linux/llist.h>
++#include <linux/delay.h>
+
+ #include "rds_single_path.h"
+ #include "ib_mr.h"
+@@ -210,7 +211,7 @@
+ for_each_online_cpu(cpu) {
+ flag = &per_cpu(clean_list_grace, cpu);
+ while (test_bit(CLEAN_LIST_BUSY_BIT, flag))
+- cpu_relax();
++ cpu_chill();
+ }
+ }
+
+diff -Nur linux-4.8.15.orig/net/rxrpc/security.c linux-4.8.15/net/rxrpc/security.c
+--- linux-4.8.15.orig/net/rxrpc/security.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/net/rxrpc/security.c 2017-01-01 17:07:16.131433400 +0100
+@@ -19,9 +19,6 @@
+ #include <keys/rxrpc-type.h>
+ #include "ar-internal.h"
+
+-static LIST_HEAD(rxrpc_security_methods);
+-static DECLARE_RWSEM(rxrpc_security_sem);
+-
+ static const struct rxrpc_security *rxrpc_security_types[] = {
+ [RXRPC_SECURITY_NONE] = &rxrpc_no_security,
+ #ifdef CONFIG_RXKAD
+diff -Nur linux-4.8.15.orig/net/sched/sch_api.c linux-4.8.15/net/sched/sch_api.c
+--- linux-4.8.15.orig/net/sched/sch_api.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/net/sched/sch_api.c 2017-01-01 17:07:16.131433400 +0100
+@@ -975,7 +975,7 @@
+ rcu_assign_pointer(sch->stab, stab);
+ }
+ if (tca[TCA_RATE]) {
+- seqcount_t *running;
++ net_seqlock_t *running;
+
+ err = -EOPNOTSUPP;
+ if (sch->flags & TCQ_F_MQROOT)
+diff -Nur linux-4.8.15.orig/net/sched/sch_generic.c linux-4.8.15/net/sched/sch_generic.c
+--- linux-4.8.15.orig/net/sched/sch_generic.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/net/sched/sch_generic.c 2017-01-01 17:07:16.131433400 +0100
+@@ -426,7 +426,11 @@
+ .list = LIST_HEAD_INIT(noop_qdisc.list),
+ .q.lock = __SPIN_LOCK_UNLOCKED(noop_qdisc.q.lock),
+ .dev_queue = &noop_netdev_queue,
++#ifdef CONFIG_PREEMPT_RT_BASE
++ .running = __SEQLOCK_UNLOCKED(noop_qdisc.running),
++#else
+ .running = SEQCNT_ZERO(noop_qdisc.running),
++#endif
+ .busylock = __SPIN_LOCK_UNLOCKED(noop_qdisc.busylock),
+ };
+ EXPORT_SYMBOL(noop_qdisc);
+@@ -620,9 +624,17 @@
+ lockdep_set_class(&sch->busylock,
+ dev->qdisc_tx_busylock ?: &qdisc_tx_busylock);
+
++#ifdef CONFIG_PREEMPT_RT_BASE
++ seqlock_init(&sch->running);
++ lockdep_set_class(&sch->running.seqcount,
++ dev->qdisc_running_key ?: &qdisc_running_key);
++ lockdep_set_class(&sch->running.lock,
++ dev->qdisc_running_key ?: &qdisc_running_key);
++#else
+ seqcount_init(&sch->running);
+ lockdep_set_class(&sch->running,
+ dev->qdisc_running_key ?: &qdisc_running_key);
++#endif
+
+ sch->ops = ops;
+ sch->enqueue = ops->enqueue;
+@@ -917,7 +929,7 @@
+ /* Wait for outstanding qdisc_run calls. */
+ list_for_each_entry(dev, head, close_list)
+ while (some_qdisc_is_busy(dev))
+- yield();
++ msleep(1);
+ }
+
+ void dev_deactivate(struct net_device *dev)
+diff -Nur linux-4.8.15.orig/net/sunrpc/svc_xprt.c linux-4.8.15/net/sunrpc/svc_xprt.c
+--- linux-4.8.15.orig/net/sunrpc/svc_xprt.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/net/sunrpc/svc_xprt.c 2017-01-01 17:07:16.131433400 +0100
+@@ -396,7 +396,7 @@
+ goto out;
+ }
+
+- cpu = get_cpu();
++ cpu = get_cpu_light();
+ pool = svc_pool_for_cpu(xprt->xpt_server, cpu);
+
+ atomic_long_inc(&pool->sp_stats.packets);
+@@ -432,7 +432,7 @@
+
+ atomic_long_inc(&pool->sp_stats.threads_woken);
+ wake_up_process(rqstp->rq_task);
+- put_cpu();
++ put_cpu_light();
+ goto out;
+ }
+ rcu_read_unlock();
+@@ -453,7 +453,7 @@
+ goto redo_search;
+ }
+ rqstp = NULL;
+- put_cpu();
++ put_cpu_light();
+ out:
+ trace_svc_xprt_do_enqueue(xprt, rqstp);
+ }
+diff -Nur linux-4.8.15.orig/scripts/mkcompile_h linux-4.8.15/scripts/mkcompile_h
+--- linux-4.8.15.orig/scripts/mkcompile_h 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/scripts/mkcompile_h 2017-01-01 17:07:16.131433400 +0100
+@@ -4,7 +4,8 @@
+ ARCH=$2
+ SMP=$3
+ PREEMPT=$4
+-CC=$5
++RT=$5
++CC=$6
+
+ vecho() { [ "${quiet}" = "silent_" ] || echo "$@" ; }
+
+@@ -57,6 +58,7 @@
+ CONFIG_FLAGS=""
+ if [ -n "$SMP" ] ; then CONFIG_FLAGS="SMP"; fi
+ if [ -n "$PREEMPT" ] ; then CONFIG_FLAGS="$CONFIG_FLAGS PREEMPT"; fi
++if [ -n "$RT" ] ; then CONFIG_FLAGS="$CONFIG_FLAGS RT"; fi
+ UTS_VERSION="$UTS_VERSION $CONFIG_FLAGS $TIMESTAMP"
+
+ # Truncate to maximum length
+diff -Nur linux-4.8.15.orig/sound/core/pcm_native.c linux-4.8.15/sound/core/pcm_native.c
+--- linux-4.8.15.orig/sound/core/pcm_native.c 2016-12-15 17:50:48.000000000 +0100
++++ linux-4.8.15/sound/core/pcm_native.c 2017-01-01 17:07:16.135433664 +0100
+@@ -135,7 +135,7 @@
+ void snd_pcm_stream_lock_irq(struct snd_pcm_substream *substream)
+ {
+ if (!substream->pcm->nonatomic)
+- local_irq_disable();
++ local_irq_disable_nort();
+ snd_pcm_stream_lock(substream);
+ }
+ EXPORT_SYMBOL_GPL(snd_pcm_stream_lock_irq);
+@@ -150,7 +150,7 @@
+ {
+ snd_pcm_stream_unlock(substream);
+ if (!substream->pcm->nonatomic)
+- local_irq_enable();
++ local_irq_enable_nort();
+ }
+ EXPORT_SYMBOL_GPL(snd_pcm_stream_unlock_irq);
+
+@@ -158,7 +158,7 @@
+ {
+ unsigned long flags = 0;
+ if (!substream->pcm->nonatomic)
+- local_irq_save(flags);
++ local_irq_save_nort(flags);
+ snd_pcm_stream_lock(substream);
+ return flags;
+ }
+@@ -176,7 +176,7 @@
+ {
+ snd_pcm_stream_unlock(substream);
+ if (!substream->pcm->nonatomic)
+- local_irq_restore(flags);
++ local_irq_restore_nort(flags);
+ }
+ EXPORT_SYMBOL_GPL(snd_pcm_stream_unlock_irqrestore);
+