/* Definition for thread-local data handling. nptl/x86_64 version. Copyright (C) 2002 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 #ifndef __ASSEMBLER__ # include # include # include /* Type for the dtv. */ typedef union dtv { size_t counter; void *pointer; } dtv_t; typedef struct { void *tcb; /* Pointer to the TCB. Not necessary the thread descriptor used by libpthread. */ dtv_t *dtv; void *self; /* Pointer to the thread descriptor. */ } tcbhead_t; #endif /* We require TLS support in the tools. */ #ifndef HAVE_TLS_SUPPORT # error "TLS support is required." #endif /* 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 /* 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 /* This is the size of the initial TCB. */ # define TLS_INIT_TCB_SIZE sizeof (tcbhead_t) /* Alignment requirements for the initial TCB. */ # define TLS_INIT_TCB_ALIGN __alignof__ (tcbhead_t) /* 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(dtv) \ ({ struct pthread *__pd; \ THREAD_SETMEM (__pd, header.data.dtvp, dtv); }) /* Return dtv of given thread descriptor. */ # define GET_DTV(descr) \ (((tcbhead_t *) (descr))->dtv) # 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 /* 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" (_descr) \ : "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.data.dtvp); }) /* 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,%0" : "=r" (__self) \ : "i" (offsetof (struct pthread, header.data.self))); \ __self;}) /* Read member of the thread descriptor directly. */ # define THREAD_GETMEM(descr, member) \ ({ __typeof (descr->member) __value; \ if (sizeof (__value) == 1) \ asm ("movb %%fs:%P2,%b0" \ : "=q" (__value) \ : "0" (0), "i" (offsetof (struct pthread, member))); \ else if (sizeof (__value) == 4) \ asm ("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 ("movq %%fs:%P1,%0" \ : "=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 ("movb %%fs:%P2(%3),%b0" \ : "=q" (__value) \ : "0" (0), "i" (offsetof (struct pthread, member[0])), \ "r" (idx)); \ else if (sizeof (__value) == 4) \ asm ("movl %%fs:%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 ("movq %%fs:%P1(,%2,8),%0" \ : "=r" (__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 %0,%%fs:%P1" : \ : "iq" (value), \ "i" (offsetof (struct pthread, member))); \ else if (sizeof (descr->member) == 4) \ asm volatile ("movl %0,%%fs:%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 ("movq %0,%%fs:%P1" : \ : "ir" ((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 %0,%%fs:%P1(%2)" : \ : "iq" (value), \ "i" (offsetof (struct pthread, member[0])), \ "r" (idx)); \ else if (sizeof (descr->member[0]) == 4) \ asm volatile ("movl %0,%%fs:%P1(,%2,4)" : \ : "ir" (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 %0,%%fs:%P1(,%2,8)" : \ : "r" ((unsigned long int) value), \ "i" (offsetof (struct pthread, member[0])), \ "r" (idx)); \ }}) #endif /* __ASSEMBLER__ */ #endif /* tls.h */