/* Definition for thread-local data handling. nptl/x86_64 version. Copyright (C) 2002-2018 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 . */ #ifndef _TLS_H #define _TLS_H 1 #ifndef __ASSEMBLER__ # include /* For ARCH_SET_FS. */ # include # include # include # include # include # include /* For cast_to_integer. */ # include # include /* Replacement type for __m128 since this file is included by ld.so, which is compiled with -mno-sse. It must not change the alignment of rtld_savespace_sse. */ typedef struct { int i[4]; } __128bits; 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]; /* Bit 0: X86_FEATURE_1_IBT. Bit 1: X86_FEATURE_1_SHSTK. */ unsigned int feature_1; int __glibc_unused1; /* Reservation of some values for the TM ABI. */ void *__private_tm[4]; /* GCC split stack support. */ void *__private_ss; long int __glibc_reserved2; /* Must be kept even if it is no longer used by glibc since programs, like AddressSanitizer, depend on the size of tcbhead_t. */ __128bits __glibc_unused2[8][4] __attribute__ ((aligned (32))); void *__padding[8]; } tcbhead_t; # ifdef __ILP32__ /* morestack.S in libgcc uses offset 0x40 to access __private_ss, */ _Static_assert (offsetof (tcbhead_t, __private_ss) == 0x40, "offset of __private_ss != 0x40"); # else /* morestack.S in libgcc uses offset 0x70 to access __private_ss, */ _Static_assert (offsetof (tcbhead_t, __private_ss) == 0x70, "offset of __private_ss != 0x70"); # endif #else /* __ASSEMBLER__ */ # include #endif /* Alignment requirement for the stack. */ #define STACK_ALIGN 16 #ifndef __ASSEMBLER__ /* Get system call information. */ # include #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) /* 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 # define TLS_DTV_AT_TP 0 /* Get the thread descriptor definition. */ # include /* 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) /* 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) \ ({ 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; \ }) # define TLS_DEFINE_INIT_TP(tp, pd) void *tp = (pd) /* 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 ("mov %%fs:%c1,%0" : "=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 /* 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 /* Set member of the thread descriptor directly. */ # 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 ((uint64_t) cast_to_integer (value)), \ "i" (offsetof (struct pthread, member))); \ }}) /* Same as THREAD_SETMEM, but the member offset can be non-constant. */ # 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 ((uint64_t) cast_to_integer (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_IN_TCB 1 # 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) () #endif /* __ASSEMBLER__ */ #endif /* tls.h */