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+/* Copyright (C) 2002-2007, 2008, 2009 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+#include <assert.h>
+#include <errno.h>
+#include <limits.h>
+#include <signal.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/param.h>
+#include <sys/resource.h>
+#include <pthreadP.h>
+#include <atomic.h>
+#include <ldsodefs.h>
+#include <tls.h>
+#include <fork.h>
+#include <version.h>
+#include <smp.h>
+#include <lowlevellock.h>
+#include <bits/kernel-features.h>
+
+
+/* Size and alignment of static TLS block. */
+size_t __static_tls_size;
+size_t __static_tls_align_m1;
+
+#ifndef __ASSUME_SET_ROBUST_LIST
+/* Negative if we do not have the system call and we can use it. */
+int __set_robust_list_avail;
+# define set_robust_list_not_avail() \
+ __set_robust_list_avail = -1
+#else
+# define set_robust_list_not_avail() do { } while (0)
+#endif
+
+#ifndef __ASSUME_FUTEX_CLOCK_REALTIME
+/* Nonzero if we do not have FUTEX_CLOCK_REALTIME. */
+int __have_futex_clock_realtime;
+# define __set_futex_clock_realtime() \
+ __have_futex_clock_realtime = 1
+#else
+#define __set_futex_clock_realtime() do { } while (0)
+#endif
+
+/* Version of the library, used in libthread_db to detect mismatches. */
+static const char nptl_version[] __attribute_used__ = VERSION;
+
+
+#ifndef SHARED
+extern void __libc_setup_tls (size_t tcbsize, size_t tcbalign);
+#endif
+
+#ifdef SHARED
+static void nptl_freeres (void);
+
+
+static const struct pthread_functions pthread_functions =
+ {
+ .ptr_pthread_attr_destroy = __pthread_attr_destroy,
+ .ptr___pthread_attr_init_2_1 = __pthread_attr_init_2_1,
+ .ptr_pthread_attr_getdetachstate = __pthread_attr_getdetachstate,
+ .ptr_pthread_attr_setdetachstate = __pthread_attr_setdetachstate,
+ .ptr_pthread_attr_getinheritsched = __pthread_attr_getinheritsched,
+ .ptr_pthread_attr_setinheritsched = __pthread_attr_setinheritsched,
+ .ptr_pthread_attr_getschedparam = __pthread_attr_getschedparam,
+ .ptr_pthread_attr_setschedparam = __pthread_attr_setschedparam,
+ .ptr_pthread_attr_getschedpolicy = __pthread_attr_getschedpolicy,
+ .ptr_pthread_attr_setschedpolicy = __pthread_attr_setschedpolicy,
+ .ptr_pthread_attr_getscope = __pthread_attr_getscope,
+ .ptr_pthread_attr_setscope = __pthread_attr_setscope,
+ .ptr_pthread_condattr_destroy = __pthread_condattr_destroy,
+ .ptr_pthread_condattr_init = __pthread_condattr_init,
+ .ptr___pthread_cond_broadcast = __pthread_cond_broadcast,
+ .ptr___pthread_cond_destroy = __pthread_cond_destroy,
+ .ptr___pthread_cond_init = __pthread_cond_init,
+ .ptr___pthread_cond_signal = __pthread_cond_signal,
+ .ptr___pthread_cond_wait = __pthread_cond_wait,
+ .ptr___pthread_cond_timedwait = __pthread_cond_timedwait,
+ .ptr_pthread_equal = __pthread_equal,
+ .ptr___pthread_exit = __pthread_exit,
+ .ptr_pthread_getschedparam = __pthread_getschedparam,
+ .ptr_pthread_setschedparam = __pthread_setschedparam,
+ .ptr_pthread_mutex_destroy = INTUSE(__pthread_mutex_destroy),
+ .ptr_pthread_mutex_init = INTUSE(__pthread_mutex_init),
+ .ptr_pthread_mutex_lock = INTUSE(__pthread_mutex_lock),
+ .ptr_pthread_mutex_unlock = INTUSE(__pthread_mutex_unlock),
+ .ptr_pthread_self = __pthread_self,
+ .ptr_pthread_setcancelstate = __pthread_setcancelstate,
+ .ptr_pthread_setcanceltype = __pthread_setcanceltype,
+ .ptr___pthread_cleanup_upto = __pthread_cleanup_upto,
+ .ptr___pthread_once = __pthread_once_internal,
+ .ptr___pthread_rwlock_rdlock = __pthread_rwlock_rdlock_internal,
+ .ptr___pthread_rwlock_wrlock = __pthread_rwlock_wrlock_internal,
+ .ptr___pthread_rwlock_unlock = __pthread_rwlock_unlock_internal,
+ .ptr___pthread_key_create = __pthread_key_create_internal,
+ .ptr___pthread_getspecific = __pthread_getspecific_internal,
+ .ptr___pthread_setspecific = __pthread_setspecific_internal,
+ .ptr__pthread_cleanup_push_defer = __pthread_cleanup_push_defer,
+ .ptr__pthread_cleanup_pop_restore = __pthread_cleanup_pop_restore,
+ .ptr_nthreads = &__nptl_nthreads,
+ .ptr___pthread_unwind = &__pthread_unwind,
+ .ptr__nptl_deallocate_tsd = __nptl_deallocate_tsd,
+ .ptr__nptl_setxid = __nptl_setxid,
+ /* For now only the stack cache needs to be freed. */
+ .ptr_freeres = nptl_freeres
+ };
+# define ptr_pthread_functions &pthread_functions
+#else
+# define ptr_pthread_functions NULL
+#endif
+
+
+#ifdef SHARED
+/* This function is called indirectly from the freeres code in libc. */
+static void
+__libc_freeres_fn_section
+nptl_freeres (void)
+{
+ __unwind_freeres ();
+ __free_stacks (0);
+}
+#endif
+
+
+/* For asynchronous cancellation we use a signal. This is the handler. */
+static void
+sigcancel_handler (int sig, siginfo_t *si, void *ctx)
+{
+#ifdef __ASSUME_CORRECT_SI_PID
+ /* Determine the process ID. It might be negative if the thread is
+ in the middle of a fork() call. */
+ pid_t pid = THREAD_GETMEM (THREAD_SELF, pid);
+ if (__builtin_expect (pid < 0, 0))
+ pid = -pid;
+#endif
+
+ /* Safety check. It would be possible to call this function for
+ other signals and send a signal from another process. This is not
+ correct and might even be a security problem. Try to catch as
+ many incorrect invocations as possible. */
+ if (sig != SIGCANCEL
+#ifdef __ASSUME_CORRECT_SI_PID
+ /* Kernels before 2.5.75 stored the thread ID and not the process
+ ID in si_pid so we skip this test. */
+ || si->si_pid != pid
+#endif
+ || si->si_code != SI_TKILL)
+ return;
+
+ struct pthread *self = THREAD_SELF;
+
+ int oldval = THREAD_GETMEM (self, cancelhandling);
+ while (1)
+ {
+ /* We are canceled now. When canceled by another thread this flag
+ is already set but if the signal is directly send (internally or
+ from another process) is has to be done here. */
+ int newval = oldval | CANCELING_BITMASK | CANCELED_BITMASK;
+
+ if (oldval == newval || (oldval & EXITING_BITMASK) != 0)
+ /* Already canceled or exiting. */
+ break;
+
+ int curval = THREAD_ATOMIC_CMPXCHG_VAL (self, cancelhandling, newval,
+ oldval);
+ if (curval == oldval)
+ {
+ /* Set the return value. */
+ THREAD_SETMEM (self, result, PTHREAD_CANCELED);
+
+ /* Make sure asynchronous cancellation is still enabled. */
+ if ((newval & CANCELTYPE_BITMASK) != 0)
+ /* Run the registered destructors and terminate the thread. */
+ __do_cancel ();
+
+ break;
+ }
+
+ oldval = curval;
+ }
+}
+
+
+struct xid_command *__xidcmd attribute_hidden;
+
+/* For asynchronous cancellation we use a signal. This is the handler. */
+static void
+sighandler_setxid (int sig, siginfo_t *si, void *ctx)
+{
+#ifdef __ASSUME_CORRECT_SI_PID
+ /* Determine the process ID. It might be negative if the thread is
+ in the middle of a fork() call. */
+ pid_t pid = THREAD_GETMEM (THREAD_SELF, pid);
+ if (__builtin_expect (pid < 0, 0))
+ pid = -pid;
+#endif
+
+ /* Safety check. It would be possible to call this function for
+ other signals and send a signal from another process. This is not
+ correct and might even be a security problem. Try to catch as
+ many incorrect invocations as possible. */
+ if (sig != SIGSETXID
+#ifdef __ASSUME_CORRECT_SI_PID
+ /* Kernels before 2.5.75 stored the thread ID and not the process
+ ID in si_pid so we skip this test. */
+ || si->si_pid != pid
+#endif
+ || si->si_code != SI_TKILL)
+ return;
+
+ INTERNAL_SYSCALL_DECL (err);
+ INTERNAL_SYSCALL_NCS (__xidcmd->syscall_no, err, 3, __xidcmd->id[0],
+ __xidcmd->id[1], __xidcmd->id[2]);
+
+ /* Reset the SETXID flag. */
+ struct pthread *self = THREAD_SELF;
+ int flags, newval;
+ do
+ {
+ flags = THREAD_GETMEM (self, cancelhandling);
+ newval = THREAD_ATOMIC_CMPXCHG_VAL (self, cancelhandling,
+ flags & ~SETXID_BITMASK, flags);
+ }
+ while (flags != newval);
+
+ /* And release the futex. */
+ self->setxid_futex = 1;
+ lll_futex_wake (&self->setxid_futex, 1, LLL_PRIVATE);
+
+ if (atomic_decrement_val (&__xidcmd->cntr) == 0)
+ lll_futex_wake (&__xidcmd->cntr, 1, LLL_PRIVATE);
+}
+
+
+/* When using __thread for this, we do it in libc so as not
+ to give libpthread its own TLS segment just for this. */
+extern void **__libc_dl_error_tsd (void) __attribute__ ((const));
+
+
+/* This can be set by the debugger before initialization is complete. */
+static bool __nptl_initial_report_events __attribute_used__;
+
+void
+__pthread_initialize_minimal_internal (void)
+{
+#ifndef SHARED
+ /* Unlike in the dynamically linked case the dynamic linker has not
+ taken care of initializing the TLS data structures. */
+ __libc_setup_tls (TLS_TCB_SIZE, TLS_TCB_ALIGN);
+
+ /* We must prevent gcc from being clever and move any of the
+ following code ahead of the __libc_setup_tls call. This function
+ will initialize the thread register which is subsequently
+ used. */
+ __asm __volatile ("");
+#endif
+
+ /* Minimal initialization of the thread descriptor. */
+ struct pthread *pd = THREAD_SELF;
+ INTERNAL_SYSCALL_DECL (err);
+ pd->pid = pd->tid = INTERNAL_SYSCALL (set_tid_address, err, 1, &pd->tid);
+ THREAD_SETMEM (pd, specific[0], &pd->specific_1stblock[0]);
+ THREAD_SETMEM (pd, user_stack, true);
+ if (LLL_LOCK_INITIALIZER != 0)
+ THREAD_SETMEM (pd, lock, LLL_LOCK_INITIALIZER);
+#if HP_TIMING_AVAIL
+ THREAD_SETMEM (pd, cpuclock_offset, GL(dl_cpuclock_offset));
+#endif
+
+ /* Initialize the robust mutex data. */
+#ifdef __PTHREAD_MUTEX_HAVE_PREV
+ pd->robust_prev = &pd->robust_head;
+#endif
+ pd->robust_head.list = &pd->robust_head;
+#ifdef __NR_set_robust_list
+ pd->robust_head.futex_offset = (offsetof (pthread_mutex_t, __data.__lock)
+ - offsetof (pthread_mutex_t,
+ __data.__list.__next));
+ int res = INTERNAL_SYSCALL (set_robust_list, err, 2, &pd->robust_head,
+ sizeof (struct robust_list_head));
+ if (INTERNAL_SYSCALL_ERROR_P (res, err))
+#endif
+ set_robust_list_not_avail ();
+
+#ifndef __ASSUME_PRIVATE_FUTEX
+ /* Private futexes are always used (at least internally) so that
+ doing the test once this early is beneficial. */
+ {
+ int word = 0;
+ word = INTERNAL_SYSCALL (futex, err, 3, &word,
+ FUTEX_WAKE | FUTEX_PRIVATE_FLAG, 1);
+ if (!INTERNAL_SYSCALL_ERROR_P (word, err))
+ THREAD_SETMEM (pd, header.private_futex, FUTEX_PRIVATE_FLAG);
+ }
+
+ /* Private futexes have been introduced earlier than the
+ FUTEX_CLOCK_REALTIME flag. We don't have to run the test if we
+ know the former are not supported. This also means we know the
+ kernel will return ENOSYS for unknown operations. */
+ if (THREAD_GETMEM (pd, header.private_futex) != 0)
+#endif
+#ifndef __ASSUME_FUTEX_CLOCK_REALTIME
+ {
+ int word = 0;
+ /* NB: the syscall actually takes six parameters. The last is the
+ bit mask. But since we will not actually wait at all the value
+ is irrelevant. Given that passing six parameters is difficult
+ on some architectures we just pass whatever random value the
+ calling convention calls for to the kernel. It causes no harm. */
+ word = INTERNAL_SYSCALL (futex, err, 5, &word,
+ FUTEX_WAIT_BITSET | FUTEX_CLOCK_REALTIME
+ | FUTEX_PRIVATE_FLAG, 1, NULL, 0);
+ assert (INTERNAL_SYSCALL_ERROR_P (word, err));
+ if (INTERNAL_SYSCALL_ERRNO (word, err) != ENOSYS)
+ __set_futex_clock_realtime ();
+ }
+#endif
+
+ /* Set initial thread's stack block from 0 up to __libc_stack_end.
+ It will be bigger than it actually is, but for unwind.c/pt-longjmp.c
+ purposes this is good enough. */
+ THREAD_SETMEM (pd, stackblock_size, (size_t) __libc_stack_end);
+
+ /* Initialize the list of all running threads with the main thread. */
+ INIT_LIST_HEAD (&__stack_user);
+ list_add (&pd->list, &__stack_user);
+
+ /* Before initializing __stack_user, the debugger could not find us and
+ had to set __nptl_initial_report_events. Propagate its setting. */
+ THREAD_SETMEM (pd, report_events, __nptl_initial_report_events);
+
+ /* Install the cancellation signal handler. If for some reason we
+ cannot install the handler we do not abort. Maybe we should, but
+ it is only asynchronous cancellation which is affected. */
+ struct sigaction sa;
+ sa.sa_sigaction = sigcancel_handler;
+ sa.sa_flags = SA_SIGINFO;
+ __sigemptyset (&sa.sa_mask);
+
+ (void) __libc_sigaction (SIGCANCEL, &sa, NULL);
+
+ /* Install the handle to change the threads' uid/gid. */
+ sa.sa_sigaction = sighandler_setxid;
+ sa.sa_flags = SA_SIGINFO | SA_RESTART;
+
+ (void) __libc_sigaction (SIGSETXID, &sa, NULL);
+
+ /* The parent process might have left the signals blocked. Just in
+ case, unblock it. We reuse the signal mask in the sigaction
+ structure. It is already cleared. */
+ __sigaddset (&sa.sa_mask, SIGCANCEL);
+ __sigaddset (&sa.sa_mask, SIGSETXID);
+ (void) INTERNAL_SYSCALL (rt_sigprocmask, err, 4, SIG_UNBLOCK, &sa.sa_mask,
+ NULL, _NSIG / 8);
+
+ /* Get the size of the static and alignment requirements for the TLS
+ block. */
+ size_t static_tls_align;
+ _dl_get_tls_static_info (&__static_tls_size, &static_tls_align);
+
+ /* Make sure the size takes all the alignments into account. */
+ if (STACK_ALIGN > static_tls_align)
+ static_tls_align = STACK_ALIGN;
+ __static_tls_align_m1 = static_tls_align - 1;
+
+ __static_tls_size = roundup (__static_tls_size, static_tls_align);
+
+ /* Determine the default allowed stack size. This is the size used
+ in case the user does not specify one. */
+ struct rlimit limit;
+ if (getrlimit (RLIMIT_STACK, &limit) != 0
+ || limit.rlim_cur == RLIM_INFINITY)
+ /* The system limit is not usable. Use an architecture-specific
+ default. */
+ limit.rlim_cur = ARCH_STACK_DEFAULT_SIZE;
+ else if (limit.rlim_cur < PTHREAD_STACK_MIN)
+ /* The system limit is unusably small.
+ Use the minimal size acceptable. */
+ limit.rlim_cur = PTHREAD_STACK_MIN;
+
+ /* Make sure it meets the minimum size that allocate_stack
+ (allocatestack.c) will demand, which depends on the page size. */
+ const uintptr_t pagesz = sysconf (_SC_PAGESIZE);
+ const size_t minstack = pagesz + __static_tls_size + MINIMAL_REST_STACK;
+ if (limit.rlim_cur < minstack)
+ limit.rlim_cur = minstack;
+
+ /* Round the resource limit up to page size. */
+ limit.rlim_cur = (limit.rlim_cur + pagesz - 1) & -pagesz;
+ __default_stacksize = limit.rlim_cur;
+
+#ifdef SHARED
+ /* Transfer the old value from the dynamic linker's internal location. */
+ *__libc_dl_error_tsd () = *(*GL(dl_error_catch_tsd)) ();
+ GL(dl_error_catch_tsd) = &__libc_dl_error_tsd;
+
+#endif
+
+ GL(dl_init_static_tls) = &__pthread_init_static_tls;
+
+ /* Register the fork generation counter with the libc. */
+#ifndef TLS_MULTIPLE_THREADS_IN_TCB
+ __libc_multiple_threads_ptr =
+#endif
+ __libc_pthread_init (&__fork_generation, __reclaim_stacks,
+ ptr_pthread_functions);
+
+ /* Determine whether the machine is SMP or not. */
+ __is_smp = is_smp_system ();
+}
+strong_alias (__pthread_initialize_minimal_internal,
+ __pthread_initialize_minimal)