/* Definition for thread-local data handling. nptl/x86_64 version. Copyright (C) 2002-2007, 2008, 2009 Free Software Foundation, Inc. This file is part of the GNU C Library. 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, see <http://www.gnu.org/licenses/>. */ #ifndef _TLS_H #define _TLS_H 1 #ifndef __ASSEMBLER__ # include <asm/prctl.h> /* For ARCH_SET_FS. */ # include <stdbool.h> # include <stddef.h> # include <stdint.h> # include <stdlib.h> # include <sysdep.h> # include <bits/kernel-features.h> # include <bits/wordsize.h> # include <xmmintrin.h> /* Type for the dtv. */ typedef union dtv { size_t counter; struct { void *val; bool is_static; } pointer; } dtv_t; typedef struct { void *tcb; /* Pointer to the TCB. Not necessarily the thread descriptor used by libpthread. */ dtv_t *dtv; void *self; /* Pointer to the thread descriptor. */ int multiple_threads; int gscope_flag; uintptr_t sysinfo; uintptr_t stack_guard; uintptr_t pointer_guard; unsigned long int vgetcpu_cache[2]; # ifndef __ASSUME_PRIVATE_FUTEX int private_futex; # else int __unused1; # endif # if __WORDSIZE == 64 int rtld_must_xmm_save; # endif /* Reservation of some values for the TM ABI. */ void *__private_tm[5]; # if __WORDSIZE == 64 long int __unused2; /* Have space for the post-AVX register size. */ __m128 rtld_savespace_sse[8][4]; void *__padding[8]; # endif } tcbhead_t; #else /* __ASSEMBLER__ */ # include <tcb-offsets.h> #endif /* We require TLS support in the tools. */ #define HAVE_TLS_SUPPORT 1 #define HAVE___THREAD 1 #define HAVE_TLS_MODEL_ATTRIBUTE 1 /* Signal that TLS support is available. */ #define USE_TLS 1 /* Alignment requirement for the stack. */ #define STACK_ALIGN 16 #ifndef __ASSEMBLER__ /* Get system call information. */ # include <sysdep.h> /* Get the thread descriptor definition. */ # include <descr.h> #ifndef LOCK_PREFIX # ifdef UP # define LOCK_PREFIX /* nothing */ # else # define LOCK_PREFIX "lock;" # endif #endif /* This is the size of the initial TCB. Can't be just sizeof (tcbhead_t), because NPTL getpid, __libc_alloca_cutoff etc. need (almost) the whole struct pthread even when not linked with -lpthread. */ # define TLS_INIT_TCB_SIZE sizeof (struct pthread) /* Alignment requirements for the initial TCB. */ # define TLS_INIT_TCB_ALIGN __alignof__ (struct pthread) /* This is the size of the TCB. */ # define TLS_TCB_SIZE sizeof (struct pthread) /* Alignment requirements for the TCB. */ //# define TLS_TCB_ALIGN __alignof__ (struct pthread) // Normally the above would be correct But we have to store post-AVX // vector registers in the TCB and we want the storage to be aligned. // unfortunately there isn't yet a type for these values and hence no // 32-byte alignment requirement. Make this explicit, for now. # define TLS_TCB_ALIGN 32 /* The TCB can have any size and the memory following the address the thread pointer points to is unspecified. Allocate the TCB there. */ # define TLS_TCB_AT_TP 1 /* Install the dtv pointer. The pointer passed is to the element with index -1 which contain the length. */ # define INSTALL_DTV(descr, dtvp) \ ((tcbhead_t *) (descr))->dtv = (dtvp) + 1 /* Install new dtv for current thread. */ # define INSTALL_NEW_DTV(dtvp) \ ({ struct pthread *__pd; \ THREAD_SETMEM (__pd, header.dtv, (dtvp)); }) /* Return dtv of given thread descriptor. */ # define GET_DTV(descr) \ (((tcbhead_t *) (descr))->dtv) /* Macros to load from and store into segment registers. */ # define TLS_GET_FS() \ ({ int __seg; __asm__ ("movl %%fs, %0" : "=q" (__seg)); __seg; }) # define TLS_SET_FS(val) \ __asm__ ("movl %0, %%fs" :: "q" (val)) /* Code to initially initialize the thread pointer. This might need special attention since 'errno' is not yet available and if the operation can cause a failure 'errno' must not be touched. We have to make the syscall for both uses of the macro since the address might be (and probably is) different. */ # define TLS_INIT_TP(thrdescr, secondcall) \ ({ void *_thrdescr = (thrdescr); \ tcbhead_t *_head = _thrdescr; \ int _result; \ \ _head->tcb = _thrdescr; \ /* For now the thread descriptor is at the same address. */ \ _head->self = _thrdescr; \ \ /* It is a simple syscall to set the %fs value for the thread. */ \ __asm__ __volatile__ ("syscall" \ : "=a" (_result) \ : "0" ((unsigned long int) __NR_arch_prctl), \ "D" ((unsigned long int) ARCH_SET_FS), \ "S" (_thrdescr) \ : "memory", "cc", "r11", "cx"); \ \ _result ? "cannot set %fs base address for thread-local storage" : 0; \ }) /* Return the address of the dtv for the current thread. */ # define THREAD_DTV() \ ({ struct pthread *__pd; \ THREAD_GETMEM (__pd, header.dtv); }) /* Return the thread descriptor for the current thread. The contained asm must *not* be marked __volatile__ since otherwise assignments like pthread_descr self = thread_self(); do not get optimized away. */ # define THREAD_SELF \ ({ struct pthread *__self; \ __asm__ ("movq %%fs:%c1,%q0" : "=r" (__self) \ : "i" (offsetof (struct pthread, header.self))); \ __self;}) /* Magic for libthread_db to know how to do THREAD_SELF. */ # define DB_THREAD_SELF_INCLUDE <sys/reg.h> /* For the FS constant. */ # define DB_THREAD_SELF CONST_THREAD_AREA (64, FS) /* Read member of the thread descriptor directly. */ # define THREAD_GETMEM(descr, member) \ ({ __typeof (descr->member) __value; \ if (sizeof (__value) == 1) \ __asm__ __volatile__ ("movb %%fs:%P2,%b0" \ : "=q" (__value) \ : "0" (0), "i" (offsetof (struct pthread, member))); \ else if (sizeof (__value) == 4) \ __asm__ __volatile__ ("movl %%fs:%P1,%0" \ : "=r" (__value) \ : "i" (offsetof (struct pthread, member))); \ else \ { \ if (sizeof (__value) != 8) \ /* There should not be any value with a size other than 1, \ 4 or 8. */ \ abort (); \ \ __asm__ __volatile__ ("movq %%fs:%P1,%q0" \ : "=r" (__value) \ : "i" (offsetof (struct pthread, member))); \ } \ __value; }) /* Same as THREAD_GETMEM, but the member offset can be non-constant. */ # define THREAD_GETMEM_NC(descr, member, idx) \ ({ __typeof (descr->member[0]) __value; \ if (sizeof (__value) == 1) \ __asm__ __volatile__ ("movb %%fs:%P2(%q3),%b0" \ : "=q" (__value) \ : "0" (0), "i" (offsetof (struct pthread, member[0])), \ "r" (idx)); \ else if (sizeof (__value) == 4) \ __asm__ __volatile__ ("movl %%fs:%P1(,%q2,4),%0" \ : "=r" (__value) \ : "i" (offsetof (struct pthread, member[0])), "r" (idx));\ else \ { \ if (sizeof (__value) != 8) \ /* There should not be any value with a size other than 1, \ 4 or 8. */ \ abort (); \ \ __asm__ __volatile__ ("movq %%fs:%P1(,%q2,8),%q0" \ : "=r" (__value) \ : "i" (offsetof (struct pthread, member[0])), \ "r" (idx)); \ } \ __value; }) /* Loading addresses of objects on x86-64 needs to be treated special when generating PIC code. */ #ifdef __pic__ # define IMM_MODE "nr" #else # define IMM_MODE "ir" #endif /* Same as THREAD_SETMEM, but the member offset can be non-constant. */ # define THREAD_SETMEM(descr, member, value) \ ({ if (sizeof (descr->member) == 1) \ __asm__ __volatile__ ("movb %b0,%%fs:%P1" : \ : "iq" (value), \ "i" (offsetof (struct pthread, member))); \ else if (sizeof (descr->member) == 4) \ __asm__ __volatile__ ("movl %0,%%fs:%P1" : \ : IMM_MODE (value), \ "i" (offsetof (struct pthread, member))); \ else \ { \ if (sizeof (descr->member) != 8) \ /* There should not be any value with a size other than 1, \ 4 or 8. */ \ abort (); \ \ __asm__ __volatile__ ("movq %q0,%%fs:%P1" : \ : IMM_MODE ((unsigned long int) value), \ "i" (offsetof (struct pthread, member))); \ }}) /* Set member of the thread descriptor directly. */ # define THREAD_SETMEM_NC(descr, member, idx, value) \ ({ if (sizeof (descr->member[0]) == 1) \ __asm__ __volatile__ ("movb %b0,%%fs:%P1(%q2)" : \ : "iq" (value), \ "i" (offsetof (struct pthread, member[0])), \ "r" (idx)); \ else if (sizeof (descr->member[0]) == 4) \ __asm__ __volatile__ ("movl %0,%%fs:%P1(,%q2,4)" : \ : IMM_MODE (value), \ "i" (offsetof (struct pthread, member[0])), \ "r" (idx)); \ else \ { \ if (sizeof (descr->member[0]) != 8) \ /* There should not be any value with a size other than 1, \ 4 or 8. */ \ abort (); \ \ __asm__ __volatile__ ("movq %q0,%%fs:%P1(,%q2,8)" : \ : IMM_MODE ((unsigned long int) value), \ "i" (offsetof (struct pthread, member[0])), \ "r" (idx)); \ }}) /* Atomic compare and exchange on TLS, returning old value. */ # define THREAD_ATOMIC_CMPXCHG_VAL(descr, member, newval, oldval) \ ({ __typeof (descr->member) __ret; \ __typeof (oldval) __old = (oldval); \ if (sizeof (descr->member) == 4) \ __asm__ __volatile__ (LOCK_PREFIX "cmpxchgl %2, %%fs:%P3" \ : "=a" (__ret) \ : "0" (__old), "r" (newval), \ "i" (offsetof (struct pthread, member))); \ else \ /* Not necessary for other sizes in the moment. */ \ abort (); \ __ret; }) /* Atomic logical and. */ # define THREAD_ATOMIC_AND(descr, member, val) \ (void) ({ if (sizeof ((descr)->member) == 4) \ __asm__ __volatile__ (LOCK_PREFIX "andl %1, %%fs:%P0" \ :: "i" (offsetof (struct pthread, member)), \ "ir" (val)); \ else \ /* Not necessary for other sizes in the moment. */ \ abort (); }) /* Atomic set bit. */ # define THREAD_ATOMIC_BIT_SET(descr, member, bit) \ (void) ({ if (sizeof ((descr)->member) == 4) \ __asm__ __volatile__ (LOCK_PREFIX "orl %1, %%fs:%P0" \ :: "i" (offsetof (struct pthread, member)), \ "ir" (1 << (bit))); \ else \ /* Not necessary for other sizes in the moment. */ \ abort (); }) /* Set the stack guard field in TCB head. */ # define THREAD_SET_STACK_GUARD(value) \ THREAD_SETMEM (THREAD_SELF, header.stack_guard, value) # define THREAD_COPY_STACK_GUARD(descr) \ ((descr)->header.stack_guard \ = THREAD_GETMEM (THREAD_SELF, header.stack_guard)) /* Set the pointer guard field in the TCB head. */ # define THREAD_SET_POINTER_GUARD(value) \ THREAD_SETMEM (THREAD_SELF, header.pointer_guard, value) # define THREAD_COPY_POINTER_GUARD(descr) \ ((descr)->header.pointer_guard \ = THREAD_GETMEM (THREAD_SELF, header.pointer_guard)) /* Get and set the global scope generation counter in the TCB head. */ # define THREAD_GSCOPE_FLAG_UNUSED 0 # define THREAD_GSCOPE_FLAG_USED 1 # define THREAD_GSCOPE_FLAG_WAIT 2 # define THREAD_GSCOPE_RESET_FLAG() \ do \ { int __res; \ __asm__ __volatile__ ("xchgl %0, %%fs:%P1" \ : "=r" (__res) \ : "i" (offsetof (struct pthread, header.gscope_flag)), \ "0" (THREAD_GSCOPE_FLAG_UNUSED)); \ if (__res == THREAD_GSCOPE_FLAG_WAIT) \ lll_futex_wake (&THREAD_SELF->header.gscope_flag, 1, LLL_PRIVATE); \ } \ while (0) # define THREAD_GSCOPE_SET_FLAG() \ THREAD_SETMEM (THREAD_SELF, header.gscope_flag, THREAD_GSCOPE_FLAG_USED) # define THREAD_GSCOPE_WAIT() \ GL(dl_wait_lookup_done) () # ifdef SHARED /* Defined in dl-trampoline.S. */ extern void _dl_x86_64_save_sse (void); extern void _dl_x86_64_restore_sse (void); # define RTLD_CHECK_FOREIGN_CALL \ (THREAD_GETMEM (THREAD_SELF, header.rtld_must_xmm_save) != 0) /* NB: Don't use the xchg operation because that would imply a lock prefix which is expensive and unnecessary. The cache line is also not contested at all. */ # define RTLD_ENABLE_FOREIGN_CALL \ int old_rtld_must_xmm_save = THREAD_GETMEM (THREAD_SELF, \ header.rtld_must_xmm_save); \ THREAD_SETMEM (THREAD_SELF, header.rtld_must_xmm_save, 1) # define RTLD_PREPARE_FOREIGN_CALL \ do if (THREAD_GETMEM (THREAD_SELF, header.rtld_must_xmm_save)) \ { \ _dl_x86_64_save_sse (); \ THREAD_SETMEM (THREAD_SELF, header.rtld_must_xmm_save, 0); \ } \ while (0) # define RTLD_FINALIZE_FOREIGN_CALL \ do { \ if (THREAD_GETMEM (THREAD_SELF, header.rtld_must_xmm_save) == 0) \ _dl_x86_64_restore_sse (); \ THREAD_SETMEM (THREAD_SELF, header.rtld_must_xmm_save, \ old_rtld_must_xmm_save); \ } while (0) # endif #endif /* __ASSEMBLER__ */ #endif /* tls.h */