| /* Definition for thread-local data handling. nptl/i386 version. |
| Copyright (C) 2002-2007, 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, write to the Free |
| Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA |
| 02111-1307 USA. */ |
| |
| #ifndef _TLS_H |
| #define _TLS_H 1 |
| |
| #include <dl-sysdep.h> |
| #ifndef __ASSEMBLER__ |
| # include <stdbool.h> |
| # include <stddef.h> |
| # include <stdint.h> |
| # include <stdlib.h> |
| # include <list.h> |
| # include <sysdep.h> |
| # include <kernel-features.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; |
| uintptr_t sysinfo; |
| uintptr_t stack_guard; |
| uintptr_t pointer_guard; |
| int gscope_flag; |
| #ifndef __ASSUME_PRIVATE_FUTEX |
| int private_futex; |
| #else |
| int __unused1; |
| #endif |
| /* Reservation of some values for the TM ABI. */ |
| void *__private_tm[5]; |
| } tcbhead_t; |
| |
| # define TLS_MULTIPLE_THREADS_IN_TCB 1 |
| |
| #else /* __ASSEMBLER__ */ |
| # include <tcb-offsets.h> |
| #endif |
| |
| |
| /* We require TLS support in the tools. */ |
| #ifndef HAVE_TLS_SUPPORT |
| # error "TLS support is required." |
| #endif |
| |
| /* Alignment requirement for the stack. For IA-32 this is governed by |
| the SSE memory functions. */ |
| #define STACK_ALIGN 16 |
| |
| #ifndef __ASSEMBLER__ |
| /* Get system call information. */ |
| # include <sysdep.h> |
| |
| /* The old way: using LDT. */ |
| |
| /* Structure passed to `modify_ldt', 'set_thread_area', and 'clone' calls. */ |
| struct user_desc |
| { |
| unsigned int entry_number; |
| unsigned long int base_addr; |
| unsigned int limit; |
| unsigned int seg_32bit:1; |
| unsigned int contents:2; |
| unsigned int read_exec_only:1; |
| unsigned int limit_in_pages:1; |
| unsigned int seg_not_present:1; |
| unsigned int useable:1; |
| unsigned int empty:25; |
| }; |
| |
| /* Initializing bit fields is slow. We speed it up by using a union. */ |
| union user_desc_init |
| { |
| struct user_desc desc; |
| unsigned int vals[4]; |
| }; |
| |
| |
| /* Get the thread descriptor definition. */ |
| # include <nptl/descr.h> |
| |
| /* 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 |
| |
| |
| /* 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) |
| |
| #define THREAD_SELF_SYSINFO THREAD_GETMEM (THREAD_SELF, header.sysinfo) |
| #define THREAD_SYSINFO(pd) ((pd)->header.sysinfo) |
| |
| /* Macros to load from and store into segment registers. */ |
| # ifndef TLS_GET_GS |
| # define TLS_GET_GS() \ |
| ({ int __seg; __asm ("movw %%gs, %w0" : "=q" (__seg)); __seg & 0xffff; }) |
| # endif |
| # ifndef TLS_SET_GS |
| # define TLS_SET_GS(val) \ |
| __asm ("movw %w0, %%gs" :: "q" (val)) |
| # endif |
| |
| |
| # ifndef __NR_set_thread_area |
| # define __NR_set_thread_area 243 |
| # endif |
| # ifndef TLS_FLAG_WRITABLE |
| # define TLS_FLAG_WRITABLE 0x00000001 |
| # endif |
| |
| // XXX Enable for the real world. |
| #if 0 |
| # ifndef __ASSUME_SET_THREAD_AREA |
| # error "we need set_thread_area" |
| # endif |
| #endif |
| |
| # ifdef __PIC__ |
| # define TLS_EBX_ARG "r" |
| # define TLS_LOAD_EBX "xchgl %3, %%ebx\n\t" |
| # else |
| # define TLS_EBX_ARG "b" |
| # define TLS_LOAD_EBX |
| # endif |
| |
| #if defined NEED_DL_SYSINFO |
| # define INIT_SYSINFO \ |
| _head->sysinfo = GLRO(dl_sysinfo) |
| #else |
| # define INIT_SYSINFO |
| #endif |
| |
| #ifndef LOCK_PREFIX |
| # ifdef UP |
| # define LOCK_PREFIX /* nothing */ |
| # else |
| # define LOCK_PREFIX "lock;" |
| # endif |
| #endif |
| |
| /* 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. */ |
| # define TLS_INIT_TP(thrdescr, secondcall) \ |
| ({ void *_thrdescr = (thrdescr); \ |
| tcbhead_t *_head = _thrdescr; \ |
| union user_desc_init _segdescr; \ |
| int _result; \ |
| \ |
| _head->tcb = _thrdescr; \ |
| /* For now the thread descriptor is at the same address. */ \ |
| _head->self = _thrdescr; \ |
| /* New syscall handling support. */ \ |
| INIT_SYSINFO; \ |
| \ |
| /* The 'entry_number' field. Let the kernel pick a value. */ \ |
| if (secondcall) \ |
| _segdescr.vals[0] = TLS_GET_GS () >> 3; \ |
| else \ |
| _segdescr.vals[0] = -1; \ |
| /* The 'base_addr' field. Pointer to the TCB. */ \ |
| _segdescr.vals[1] = (unsigned long int) _thrdescr; \ |
| /* The 'limit' field. We use 4GB which is 0xfffff pages. */ \ |
| _segdescr.vals[2] = 0xfffff; \ |
| /* Collapsed value of the bitfield: \ |
| .seg_32bit = 1 \ |
| .contents = 0 \ |
| .read_exec_only = 0 \ |
| .limit_in_pages = 1 \ |
| .seg_not_present = 0 \ |
| .useable = 1 */ \ |
| _segdescr.vals[3] = 0x51; \ |
| \ |
| /* Install the TLS. */ \ |
| asm volatile (TLS_LOAD_EBX \ |
| "int $0x80\n\t" \ |
| TLS_LOAD_EBX \ |
| : "=a" (_result), "=m" (_segdescr.desc.entry_number) \ |
| : "0" (__NR_set_thread_area), \ |
| TLS_EBX_ARG (&_segdescr.desc), "m" (_segdescr.desc)); \ |
| \ |
| if (_result == 0) \ |
| /* We know the index in the GDT, now load the segment register. \ |
| The use of the GDT is described by the value 3 in the lower \ |
| three bits of the segment descriptor value. \ |
| \ |
| Note that we have to do this even if the numeric value of \ |
| the descriptor does not change. Loading the segment register \ |
| causes the segment information from the GDT to be loaded \ |
| which is necessary since we have changed it. */ \ |
| TLS_SET_GS (_segdescr.desc.entry_number * 8 + 3); \ |
| \ |
| _result == 0 ? NULL \ |
| : "set_thread_area failed when setting up thread-local storage\n"; }) |
| |
| |
| /* 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 ("movl %%gs:%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 \ |
| REGISTER_THREAD_AREA (32, offsetof (struct user_regs_struct, xgs), 3) \ |
| REGISTER_THREAD_AREA (64, 26 * 8, 3) /* x86-64's user_regs_struct->gs */ |
| |
| |
| /* Read member of the thread descriptor directly. */ |
| # define THREAD_GETMEM(descr, member) \ |
| ({ __typeof (descr->member) __value; \ |
| if (sizeof (__value) == 1) \ |
| asm volatile ("movb %%gs:%P2,%b0" \ |
| : "=q" (__value) \ |
| : "0" (0), "i" (offsetof (struct pthread, member))); \ |
| else if (sizeof (__value) == 4) \ |
| asm volatile ("movl %%gs:%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 ("movl %%gs:%P1,%%eax\n\t" \ |
| "movl %%gs:%P2,%%edx" \ |
| : "=A" (__value) \ |
| : "i" (offsetof (struct pthread, member)), \ |
| "i" (offsetof (struct pthread, member) + 4)); \ |
| } \ |
| __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 %%gs:%P2(%3),%b0" \ |
| : "=q" (__value) \ |
| : "0" (0), "i" (offsetof (struct pthread, member[0])), \ |
| "r" (idx)); \ |
| else if (sizeof (__value) == 4) \ |
| asm volatile ("movl %%gs:%P1(,%2,4),%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 ("movl %%gs:%P1(,%2,8),%%eax\n\t" \ |
| "movl %%gs:4+%P1(,%2,8),%%edx" \ |
| : "=&A" (__value) \ |
| : "i" (offsetof (struct pthread, member[0])), \ |
| "r" (idx)); \ |
| } \ |
| __value; }) |
| |
| |
| /* 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,%%gs:%P1" : \ |
| : "iq" (value), \ |
| "i" (offsetof (struct pthread, member))); \ |
| else if (sizeof (descr->member) == 4) \ |
| asm volatile ("movl %0,%%gs:%P1" : \ |
| : "ir" (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 ("movl %%eax,%%gs:%P1\n\t" \ |
| "movl %%edx,%%gs:%P2" : \ |
| : "A" (value), \ |
| "i" (offsetof (struct pthread, member)), \ |
| "i" (offsetof (struct pthread, member) + 4)); \ |
| }}) |
| |
| |
| /* 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,%%gs:%P1(%2)" : \ |
| : "iq" (value), \ |
| "i" (offsetof (struct pthread, member)), \ |
| "r" (idx)); \ |
| else if (sizeof (descr->member[0]) == 4) \ |
| asm volatile ("movl %0,%%gs:%P1(,%2,4)" : \ |
| : "ir" (value), \ |
| "i" (offsetof (struct pthread, member)), \ |
| "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 ("movl %%eax,%%gs:%P1(,%2,8)\n\t" \ |
| "movl %%edx,%%gs:4+%P1(,%2,8)" : \ |
| : "A" (value), \ |
| "i" (offsetof (struct pthread, member)), \ |
| "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, %%gs:%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, %%gs:%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, %%gs:%P0" \ |
| :: "i" (offsetof (struct pthread, member)), \ |
| "ir" (1 << (bit))); \ |
| else \ |
| /* Not necessary for other sizes in the moment. */ \ |
| abort (); }) |
| |
| |
| /* Call the user-provided thread function. */ |
| #define CALL_THREAD_FCT(descr) \ |
| ({ void *__res; \ |
| int __ignore1, __ignore2; \ |
| asm volatile ("pushl %%eax\n\t" \ |
| "pushl %%eax\n\t" \ |
| "pushl %%eax\n\t" \ |
| "pushl %%gs:%P4\n\t" \ |
| "call *%%gs:%P3\n\t" \ |
| "addl $16, %%esp" \ |
| : "=a" (__res), "=c" (__ignore1), "=d" (__ignore2) \ |
| : "i" (offsetof (struct pthread, start_routine)), \ |
| "i" (offsetof (struct pthread, arg))); \ |
| __res; }) |
| |
| |
| /* 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, %%gs:%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 */ |
