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/* Copyright (C) 2002, 2003, 2004 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. */
#include <sysdep.h>
#include <lowlevelcond.h>
#include <tcb-offsets.h>
#ifdef UP
# define LOCK
#else
# define LOCK lock
#endif
#define FUTEX_WAIT 0
#define FUTEX_WAKE 1
.text
/* int pthread_cond_wait (pthread_cond_t *cond, pthread_mutex_t *mutex) */
.globl __pthread_cond_wait
.type __pthread_cond_wait, @function
.align 16
__pthread_cond_wait:
.LSTARTCODE:
pushl %edi
.Lpush_edi:
pushl %esi
.Lpush_esi:
pushl %ebx
.Lpush_ebx:
xorl %esi, %esi
movl 16(%esp), %ebx
/* Get internal lock. */
movl $1, %edx
xorl %eax, %eax
LOCK
#if cond_lock == 0
cmpxchgl %edx, (%ebx)
#else
cmpxchgl %edx, cond_lock(%ebx)
#endif
jnz 1f
/* Store the reference to the mutex. If there is already a
different value in there this is a bad user bug. */
2: cmpl $-1, dep_mutex(%ebx)
movl 20(%esp), %eax
je 15f
movl %eax, dep_mutex(%ebx)
/* Unlock the mutex. */
15: xorl %edx, %edx
call __pthread_mutex_unlock_usercnt
testl %eax, %eax
jne 12f
addl $1, total_seq(%ebx)
adcl $0, total_seq+4(%ebx)
addl $1, cond_futex(%ebx)
addl $(1 << clock_bits), cond_nwaiters(%ebx)
#define FRAME_SIZE 16
subl $FRAME_SIZE, %esp
.Lsubl:
/* Get and store current wakeup_seq value. */
movl wakeup_seq(%ebx), %edi
movl wakeup_seq+4(%ebx), %edx
movl broadcast_seq(%ebx), %eax
movl %edi, 4(%esp)
movl %edx, 8(%esp)
movl %eax, 12(%esp)
8: movl cond_futex(%ebx), %edi
/* Unlock. */
LOCK
#if cond_lock == 0
subl $1, (%ebx)
#else
subl $1, cond_lock(%ebx)
#endif
jne 3f
.LcleanupSTART:
4: call __pthread_enable_asynccancel
movl %eax, (%esp)
movl %esi, %ecx /* movl $FUTEX_WAIT, %ecx */
movl %edi, %edx
addl $cond_futex, %ebx
.Ladd_cond_futex:
movl $SYS_futex, %eax
ENTER_KERNEL
subl $cond_futex, %ebx
.Lsub_cond_futex:
movl (%esp), %eax
call __pthread_disable_asynccancel
.LcleanupEND:
/* Lock. */
movl $1, %edx
xorl %eax, %eax
LOCK
#if cond_lock == 0
cmpxchgl %edx, (%ebx)
#else
cmpxchgl %edx, cond_lock(%ebx)
#endif
jnz 5f
6: movl broadcast_seq(%ebx), %eax
cmpl 12(%esp), %eax
jne 16f
movl woken_seq(%ebx), %eax
movl woken_seq+4(%ebx), %ecx
movl wakeup_seq(%ebx), %edi
movl wakeup_seq+4(%ebx), %edx
cmpl 8(%esp), %edx
jne 7f
cmpl 4(%esp), %edi
je 8b
7: cmpl %ecx, %edx
jne 9f
cmp %eax, %edi
je 8b
9: addl $1, woken_seq(%ebx)
adcl $0, woken_seq+4(%ebx)
/* Unlock */
16: subl $(1 << clock_bits), cond_nwaiters(%ebx)
/* Wake up a thread which wants to destroy the condvar object. */
movl total_seq(%ebx), %eax
andl total_seq+4(%ebx), %eax
cmpl $0xffffffff, %eax
jne 17f
movl cond_nwaiters(%ebx), %eax
andl $~((1 << clock_bits) - 1), %eax
jne 17f
addl $cond_nwaiters, %ebx
movl $SYS_futex, %eax
movl $FUTEX_WAKE, %ecx
movl $1, %edx
ENTER_KERNEL
subl $cond_nwaiters, %ebx
17: LOCK
#if cond_lock == 0
subl $1, (%ebx)
#else
subl $1, cond_lock(%ebx)
#endif
jne 10f
11: movl 20+FRAME_SIZE(%esp), %eax
call __pthread_mutex_cond_lock
addl $FRAME_SIZE, %esp
.Laddl:
14: popl %ebx
.Lpop_ebx:
popl %esi
.Lpop_esi:
popl %edi
.Lpop_edi:
/* We return the result of the mutex_lock operation. */
ret
/* Initial locking failed. */
1:
.LSbl1:
#if cond_lock == 0
movl %ebx, %ecx
#else
leal cond_lock(%ebx), %ecx
#endif
call __lll_mutex_lock_wait
jmp 2b
/* Unlock in loop requires waekup. */
3:
.LSbl2:
#if cond_lock == 0
movl %ebx, %eax
#else
leal cond_lock(%ebx), %eax
#endif
call __lll_mutex_unlock_wake
jmp 4b
/* Locking in loop failed. */
5:
#if cond_lock == 0
movl %ebx, %ecx
#else
leal cond_lock(%ebx), %ecx
#endif
call __lll_mutex_lock_wait
jmp 6b
/* Unlock after loop requires wakeup. */
10:
#if cond_lock == 0
movl %ebx, %eax
#else
leal cond_lock(%ebx), %eax
#endif
call __lll_mutex_unlock_wake
jmp 11b
/* The initial unlocking of the mutex failed. */
12:
.LSbl3:
LOCK
#if cond_lock == 0
subl $1, (%ebx)
#else
subl $1, cond_lock(%ebx)
#endif
jne 14b
movl %eax, %esi
#if cond_lock == 0
movl %ebx, %eax
#else
leal cond_lock(%ebx), %eax
#endif
call __lll_mutex_unlock_wake
movl %esi, %eax
jmp 14b
.size __pthread_cond_wait, .-__pthread_cond_wait
weak_alias(__pthread_cond_wait, pthread_cond_wait)
.type __condvar_w_cleanup2, @function
__condvar_w_cleanup2:
subl $cond_futex, %ebx
.size __condvar_w_cleanup2, .-__condvar_w_cleanup2
.LSbl4:
.type __condvar_w_cleanup, @function
__condvar_w_cleanup:
movl %eax, %esi
/* Get internal lock. */
movl $1, %edx
xorl %eax, %eax
LOCK
#if cond_lock == 0
cmpxchgl %edx, (%ebx)
#else
cmpxchgl %edx, cond_lock(%ebx)
#endif
jz 1f
#if cond_lock == 0
movl %ebx, %ecx
#else
leal cond_lock(%ebx), %ecx
#endif
call __lll_mutex_lock_wait
1: movl broadcast_seq(%ebx), %eax
cmpl 12(%esp), %eax
jne 3f
addl $1, wakeup_seq(%ebx)
adcl $0, wakeup_seq+4(%ebx)
addl $1, cond_futex(%ebx)
addl $1, woken_seq(%ebx)
adcl $0, woken_seq+4(%ebx)
3: subl $(1 << clock_bits), cond_nwaiters(%ebx)
/* Wake up a thread which wants to destroy the condvar object. */
xorl %edi, %edi
movl total_seq(%ebx), %eax
andl total_seq+4(%ebx), %eax
cmpl $0xffffffff, %eax
jne 4f
movl cond_nwaiters(%ebx), %eax
andl $~((1 << clock_bits) - 1), %eax
jne 4f
addl $cond_nwaiters, %ebx
movl $SYS_futex, %eax
movl $FUTEX_WAKE, %ecx
movl $1, %edx
ENTER_KERNEL
subl $cond_nwaiters, %ebx
movl $1, %edi
4: LOCK
#if cond_lock == 0
subl $1, (%ebx)
#else
subl $1, cond_lock(%ebx)
#endif
je 2f
#if cond_lock == 0
movl %ebx, %eax
#else
leal cond_lock(%ebx), %eax
#endif
call __lll_mutex_unlock_wake
/* Wake up all waiters to make sure no signal gets lost. */
2: testl %edi, %edi
jnz 5f
addl $cond_futex, %ebx
movl $FUTEX_WAKE, %ecx
movl $SYS_futex, %eax
movl $0x7fffffff, %edx
ENTER_KERNEL
5: movl 20+FRAME_SIZE(%esp), %eax
call __pthread_mutex_cond_lock
movl %esi, (%esp)
.LcallUR:
call _Unwind_Resume
hlt
.LENDCODE:
.size __condvar_w_cleanup, .-__condvar_w_cleanup
|