diff options
Diffstat (limited to 'libpthread/nptl/sysdeps/i386/tls.h')
| -rw-r--r-- | libpthread/nptl/sysdeps/i386/tls.h | 429 |
1 files changed, 429 insertions, 0 deletions
diff --git a/libpthread/nptl/sysdeps/i386/tls.h b/libpthread/nptl/sysdeps/i386/tls.h new file mode 100644 index 000000000..52bde9eec --- /dev/null +++ b/libpthread/nptl/sysdeps/i386/tls.h @@ -0,0 +1,429 @@ +/* Definition for thread-local data handling. nptl/i386 version. + Copyright (C) 2002, 2003, 2004, 2005 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 <stdbool.h> +# include <stddef.h> +# include <stdint.h> +# include <stdlib.h> +# include <list.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; +} tcbhead_t; + +# define TLS_MULTIPLE_THREADS_IN_TCB 1 + +#else /* __ASSEMBLER__ */ +# include <tcb-offsets.h> +#endif + + +/* We require TLS support in the tools. */ +#define HAVE_TLS_SUPPORT +#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. 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]; +}; + + +/* 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) + +/* Get the thread descriptor definition. */ +#include <descr.h> + +/* 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 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)) + + +#endif /* __ASSEMBLER__ */ + +#endif /* tls.h */ |