diff options
Diffstat (limited to 'nptl/sysdeps/unix/sysv/linux/i386/lowlevellock.h')
| -rw-r--r-- | nptl/sysdeps/unix/sysv/linux/i386/lowlevellock.h | 257 |
1 files changed, 257 insertions, 0 deletions
diff --git a/nptl/sysdeps/unix/sysv/linux/i386/lowlevellock.h b/nptl/sysdeps/unix/sysv/linux/i386/lowlevellock.h new file mode 100644 index 0000000000..71babd5c93 --- /dev/null +++ b/nptl/sysdeps/unix/sysv/linux/i386/lowlevellock.h @@ -0,0 +1,257 @@ +/* Copyright (C) 2002 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Ulrich Drepper <drepper@redhat.com>, 2002. + + 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 _LOWLEVELLOCK_H +#define _LOWLEVELLOCK_H 1 + +#include <time.h> +#include <bits/pthreadtypes.h> + +#ifndef LOCK_INSTR +# ifdef UP +# define LOCK_INSTR /* nothing */ +# else +# define LOCK_INSTR "lock;" +# endif +#endif + +#define SYS_futex 240 +#define FUTEX_WAIT 0 +#define FUTEX_WAKE 1 + + +/* Initializer for compatibility lock. */ +#define LLL_MUTEX_LOCK_INITIALIZER (0) + + +/* Does not preserve %eax and %ecx. */ +extern int __lll_mutex_lock_wait (int val, int *__futex) + __attribute ((regparm (2))) attribute_hidden; +/* Does not preserver %eax, %ecx, and %edx. */ +extern int __lll_mutex_timedlock_wait (int val, int *__futex, + const struct timespec *abstime) + __attribute ((regparm (3))) attribute_hidden; +/* Preserves all registers but %eax. */ +extern int __lll_mutex_unlock_wait (int *__futex) + __attribute ((regparm (1))) attribute_hidden; + + +#define lll_mutex_trylock(futex) \ + ({ unsigned char ret; \ + __asm __volatile (LOCK_INSTR "cmpxchgl %2, %1; setne %0" \ + : "=a" (ret), "=m" (futex) \ + : "r" (1), "1" (futex), "0" (0)); \ + ret; }) + + +#define lll_mutex_lock(futex) \ + (void) ({ int ignore1, ignore2; \ + __asm (LOCK_INSTR "xaddl %0, %2\n\t" \ + "testl %0, %0\n\t" \ + "jne 1f\n\t" \ + ".subsection 1\n" \ + "1:\tleal %2, %%ecx\n\t" \ + "call __lll_mutex_lock_wait\n\t" \ + "jmp 2f\n\t" \ + ".previous\n" \ + "2:" \ + : "=a" (ignore1), "=&c" (ignore2), "=m" (futex) \ + : "0" (1), "2" (futex)); }) + + +#define lll_mutex_timedlock(futex, timeout) \ + ({ int result, ignore1, ignore2; \ + __asm (LOCK_INSTR "xaddl %0, %3\n\t" \ + "testl %0, %0\n\t" \ + "jne 1f\n\t" \ + ".subsection 1\n" \ + "1:\tleal %3, %%ecx\n\t" \ + "movl %6, %%edx\n\t" \ + "call __lll_mutex_timedlock_wait\n\t" \ + "jmp 2f\n\t" \ + ".previous\n" \ + "2:" \ + : "=a" (result), "=&c" (ignore1), "=&d" (ignore2), "=m" (futex) \ + : "0" (1), "3" (futex), "m" (timeout)); \ + result; }) + + +#define lll_mutex_unlock(futex) \ + (void) ({ int ignore; \ + __asm (LOCK_INSTR "decl %0\n\t" \ + "jne 1f\n\t" \ + ".subsection 1\n" \ + "1:\tleal %0, %%eax\n\t" \ + "call __lll_mutex_unlock_wake\n\t" \ + "jmp 2f\n\t" \ + ".previous\n" \ + "2:" \ + : "=m" (futex), "=&a" (ignore) \ + : "0" (futex)); }) + + +#define lll_mutex_islocked(futex) \ + (futex != 0) + + +/* We have a separate internal lock implementation which is not tied + to binary compatibility. */ + +/* Type for lock object. */ +typedef int lll_lock_t; + +/* Initializers for lock. */ +#define LLL_LOCK_INITIALIZER (1) +#define LLL_LOCK_INITIALIZER_LOCKED (0) + + +extern int __lll_lock_wait (int val, int *__futex) + __attribute ((regparm (2))) attribute_hidden; +extern int __lll_unlock_wake (int *__futex) + __attribute ((regparm (1))) attribute_hidden; +extern int lll_unlock_wake_cb (int *__futex) attribute_hidden; + + +/* The states of a lock are: + 1 - untaken + 0 - taken by one user + <0 - taken by more users */ + + +#define lll_trylock(futex) \ + ({ unsigned char ret; \ + __asm __volatile (LOCK_INSTR "cmpxchgl %2, %1; setne %0" \ + : "=a" (ret), "=m" (futex) \ + : "r" (0), "1" (futex), "0" (1)); \ + ret; }) + + +#define lll_lock(futex) \ + (void) ({ int ignore1, ignore2; \ + __asm (LOCK_INSTR "xaddl %0, %2\n\t" \ + "jne 1f\n\t" \ + ".subsection 1\n" \ + "1:\tleal %2, %%ecx\n\t" \ + "call __lll_lock_wait\n\t" \ + "jmp 2f\n\t" \ + ".previous\n" \ + "2:" \ + : "=a" (ignore1), "=&c" (ignore2), "=m" (futex) \ + : "0" (-1), "2" (futex)); }) + + +#define lll_unlock(futex) \ + (void) ({ int ignore; \ + __asm (LOCK_INSTR "incl %0\n\t" \ + "jng 1f\n\t" \ + ".subsection 1\n" \ + "1:\tleal %0, %%eax\n\t" \ + "call __lll_unlock_wake\n\t" \ + "jmp 2f\n\t" \ + ".previous\n" \ + "2:" \ + : "=m" (futex), "=&a" (ignore) \ + : "0" (futex)); }) + + +#define lll_islocked(futex) \ + (futex != 0) + + +/* The kernel notifies a process with uses CLONE_CLEARTID via futex + wakeup when the clone terminates. The memory location contains the + thread ID while the clone is running and is reset to zero + afterwards. + + The macro parameter must not have any side effect. */ +#ifdef PIC +# define LLL_TID_EBX_LOAD "xchgl %2, %%ebx\n" +# define LLL_TID_EBX_REG "D" +#else +# define LLL_TID_EBX_LOAD +# define LLL_TID_EBX_REG "b" +#endif +#define lll_wait_tid(tid) \ + do { \ + int __ignore; \ + register __typeof (tid) _tid asm ("edx") = (tid); \ + if (_tid != 0) \ + __asm __volatile (LLL_TID_EBX_LOAD \ + "1:\tmovl %1, %%eax\n\t" \ + "int $0x80\n\t" \ + "cmpl $0, (%%ebx)\n\t" \ + "jne,pn 1b\n\t" \ + LLL_TID_EBX_LOAD \ + : "=&a" (__ignore) \ + : "i" (SYS_futex), LLL_TID_EBX_REG (&tid), "S" (0), \ + "c" (FUTEX_WAIT), "d" (_tid)); \ + } while (0) + +extern int __lll_timedwait_tid (int *tid, const struct timespec *abstime) + __attribute__ ((regparm (2))) attribute_hidden; +#define lll_timedwait_tid(tid, abstime) \ + ({ \ + int __result = 0; \ + if (tid != 0) \ + { \ + if (abstime == NULL || abstime->tv_nsec >= 1000000000) \ + __result = EINVAL; \ + else \ + __result = __lll_timedwait_tid (&tid, abstime); \ + } \ + __result; }) + + +#define lll_wake_tid(tid) \ + do { \ + int __ignore; \ + (tid) = 0; \ + __asm __volatile (LLL_TID_EBX_LOAD \ + "\tint $0x80\n\t" \ + LLL_TID_EBX_LOAD \ + : "=a" (__ignore) \ + : "0" (SYS_futex), LLL_TID_EBX_REG (&(tid)), "S" (0), \ + "c" (FUTEX_WAKE), "d" (0x7fffffff)); \ + } while (0) + + +/* Conditional variable handling. */ + +extern void __lll_cond_wait (pthread_cond_t *cond) + __attribute ((regparm (1))) attribute_hidden; +extern int __lll_cond_timedwait (pthread_cond_t *cond, + const struct timespec *abstime) + __attribute ((regparm (2))) attribute_hidden; +extern void __lll_cond_wake (pthread_cond_t *cond) + __attribute ((regparm (1))) attribute_hidden; +extern void __lll_cond_broadcast (pthread_cond_t *cond) + __attribute ((regparm (1))) attribute_hidden; + + +#define lll_cond_wait(cond) \ + __lll_cond_wait (cond) +#define lll_cond_timedwait(cond, abstime) \ + __lll_cond_timedwait (cond, abstime) +#define lll_cond_wake(cond) \ + __lll_cond_wake (cond) +#define lll_cond_broadcast(cond) \ + __lll_cond_broadcast (cond) + + +#endif /* lowlevellock.h */ |