From f49d6407117bc173e6477b03773e56411c543c1f Mon Sep 17 00:00:00 2001 From: Ulrich Drepper Date: Mon, 10 Mar 2003 09:26:20 +0000 Subject: [PATCH] Lowlevel lock definitions for x86-64/Linux. --- nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.h | 293 +++++++++++++++++++++ 1 file changed, 293 insertions(+) create mode 100644 nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.h diff --git a/nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.h b/nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.h new file mode 100644 index 0000000..9e62768 --- /dev/null +++ b/nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.h @@ -0,0 +1,293 @@ +/* Copyright (C) 2002, 2003 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Ulrich Drepper , 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 +#include +#include + +#ifndef LOCK_INSTR +# ifdef UP +# define LOCK_INSTR /* nothing */ +# else +# define LOCK_INSTR "lock;" +# endif +#endif + +#define SYS_futex 202 +#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_hidden; +/* Does not preserver %eax, %ecx, and %edx. */ +extern int __lll_mutex_timedlock_wait (int val, int *__futex, + const struct timespec *abstime) + attribute_hidden; +/* Preserves all registers but %eax. */ +extern int __lll_mutex_unlock_wait (int *__futex) 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) \ + : "memory"); \ + ret; }) + + +#define lll_mutex_lock(futex) \ + (void) ({ int ignore1, ignore2; \ + __asm __volatile (LOCK_INSTR "xaddl %0, %2\n\t" \ + "testl %0, %0\n\t" \ + "jne 1f\n\t" \ + ".subsection 1\n" \ + "1:\tleaq %2, %%rsi\n\t" \ + "call __lll_mutex_lock_wait\n\t" \ + "jmp 2f\n\t" \ + ".previous\n" \ + "2:" \ + : "=D" (ignore1), "=&S" (ignore2), "=m" (futex) \ + : "0" (1), "2" (futex) \ + : "memory"); }) + + +#define lll_mutex_timedlock(futex, timeout) \ + ({ int result, ignore1, ignore2, ignore3; \ + __asm __volatile (LOCK_INSTR "xaddl %0, %4\n\t" \ + "testl %0, %0\n\t" \ + "jne 1f\n\t" \ + ".subsection 1\n" \ + "1:\tmovl %0, %%edi\n\t" \ + "leaq %4, %%rsi\n\t" \ + "movq %7, %%rdx\n\t" \ + "call __lll_mutex_timedlock_wait\n\t" \ + "jmp 2f\n\t" \ + ".previous\n" \ + "2:" \ + : "=a" (result), "=&D" (ignore1), "=&S" (ignore2), \ + "=&d" (ignore2), "=m" (futex) \ + : "0" (1), "4" (futex), "m" (timeout) \ + : "memory"); \ + result; }) + + +#define lll_mutex_unlock(futex) \ + (void) ({ int ignore; \ + __asm __volatile (LOCK_INSTR "decl %0\n\t" \ + "jne 1f\n\t" \ + ".subsection 1\n" \ + "1:\tleaq %0, %%rdi\n\t" \ + "call __lll_mutex_unlock_wake\n\t" \ + "jmp 2f\n\t" \ + ".previous\n" \ + "2:" \ + : "=m" (futex), "=&D" (ignore) \ + : "0" (futex) \ + : "memory"); }) + + +#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_hidden; +extern int __lll_unlock_wake (int *__futex) 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 */ + + +#if defined NOT_IN_libc || defined UP +# 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" (0) \ + : "memory"); \ + ret; }) + + +# define lll_lock(futex) \ + (void) ({ int ignore1, ignore2; \ + __asm __volatile (LOCK_INSTR "xaddl %0, %2\n\t" \ + "jne 1f\n\t" \ + ".subsection 1\n" \ + "1:\tleaq %2, %%rsi\n\t" \ + "call __lll_lock_wait\n\t" \ + "jmp 2f\n\t" \ + ".previous\n" \ + "2:" \ + : "=D" (ignore1), "=&S" (ignore2), "=m" (futex) \ + : "0" (-1), "2" (futex) \ + : "memory"); }) + + +# define lll_unlock(futex) \ + (void) ({ int ignore; \ + __asm __volatile (LOCK_INSTR "addl $1,%0\n\t" \ + "jng 1f\n\t" \ + ".subsection 1\n" \ + "1:\tleaq %0, %%rdi\n\t" \ + "call __lll_unlock_wake\n\t" \ + "jmp 2f\n\t" \ + ".previous\n" \ + "2:" \ + : "=m" (futex), "=&D" (ignore) \ + : "0" (futex) \ + : "memory"); }) +#else +/* Special versions of the macros for use in libc itself. They avoid + the lock prefix when the thread library is not used. + + XXX In future we might even want to avoid it on UP machines. */ + +# define lll_trylock(futex) \ + ({ unsigned char ret; \ + __asm __volatile ("cmpl $0, __libc_multiple_threads(%%rip)\n\t" \ + "je 0f\n\t" \ + "lock\n" \ + "0:\tcmpxchgl %2, %1; setne %0" \ + : "=a" (ret), "=m" (futex) \ + : "r" (0), "1" (futex), "0" (0) \ + : "memory"); \ + ret; }) + + +# define lll_lock(futex) \ + (void) ({ int ignore1, ignore2; \ + __asm __volatile ("cmpl $0, __libc_multiple_threads(%%rip)\n\t" \ + "je 0f\n\t" \ + "lock\n" \ + "0:\txaddl %0, %2\n\t" \ + "jne 1f\n\t" \ + ".subsection 1\n" \ + "1:\tleaq %2, %%rsi\n\t" \ + "call __lll_lock_wait\n\t" \ + "jmp 2f\n\t" \ + ".previous\n" \ + "2:" \ + : "=D" (ignore1), "=&S" (ignore2), "=m" (futex) \ + : "0" (-1), "2" (futex) \ + : "memory"); }) + + +# define lll_unlock(futex) \ + (void) ({ int ignore; \ + __asm __volatile ("cmpl $0, __libc_multiple_threads(%%rip)\n\t" \ + "je 0f\n\t" \ + "lock\n" \ + "0:\taddl $1,%0\n\t" \ + "jng 1f\n\t" \ + ".subsection 1\n" \ + "1:\tleaq %0, %%rdi\n\t" \ + "call __lll_unlock_wake\n\t" \ + "jmp 2f\n\t" \ + ".previous\n" \ + "2:" \ + : "=m" (futex), "=&D" (ignore) \ + : "0" (futex) \ + : "memory"); }) +#endif + + +#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. */ +#define lll_wait_tid(tid) \ + do { \ + int __ignore; \ + register __typeof (tid) _tid asm ("edx") = (tid); \ + if (_tid != 0) \ + __asm __volatile ("1:\tmovq %1, %%rax\n\t" \ + "syscall\n\t" \ + "cmpl $0, (%%rdi)\n\t" \ + "jne 1b" \ + : "=&a" (__ignore) \ + : "i" (SYS_futex), "D" (&tid), "r10" (0), \ + "S" (FUTEX_WAIT), "d" (_tid) \ + : "memory", "cc", "r11", "cx"); \ + } 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; }) + + +/* Conditional variable handling. */ + +extern void __lll_cond_wait (pthread_cond_t *cond) attribute_hidden; +extern int __lll_cond_timedwait (pthread_cond_t *cond, + const struct timespec *abstime) + attribute_hidden; +extern void __lll_cond_wake (pthread_cond_t *cond) attribute_hidden; +extern void __lll_cond_broadcast (pthread_cond_t *cond) 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 */ -- 2.7.4