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/* Copyright (C) 2002, 2003 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 <lowlevelrwlock.h>
#define SYS_futex 240
#define FUTEX_WAIT 0
#define FUTEX_WAKE 1
#ifndef UP
# define LOCK lock
#else
# define LOCK
#endif
.text
.globl __pthread_rwlock_unlock
.type __pthread_rwlock_unlock,@function
.align 16
__pthread_rwlock_unlock:
pushl %ebx
pushl %esi
pushl %edi
xorl %esi, %esi
xorl %edx, %edx
movl 16(%esp), %edi
/* Get the lock. */
movl $1, %eax
LOCK
#if MUTEX == 0
xaddl %eax, (%edi)
#else
xaddl %eax, MUTEX(%edi)
#endif
testl %eax, %eax
jne 1f
2: cmpl $0, WRITER(%edi)
jne 5f
decl NR_READERS(%edi)
jnz 6f
5: movl $0, WRITER(%edi)
movl $0x7fffffff, %edx
leal READERS_WAKEUP(%edi), %ebx
movl $1, %ecx
leal WRITERS_WAKEUP(%edi), %eax
cmpl $0, WRITERS_QUEUED(%edi)
#ifdef HAVE_CMOV
cmovnel %ecx, %edx
cmovnel %eax, %ebx
#else
je 0f
movl %ecx, %edx
movl %eax, %ebx
0:
#endif
movl $SYS_futex, %eax
ENTER_KERNEL
6: LOCK
#if MUTEX == 0
decl (%edi)
#else
decl MUTEX(%edi)
#endif
jne 3f
4: xorl %eax, %eax
popl %edi
popl %esi
popl %ebx
ret
1: movl %edi, %ecx
call __lll_mutex_lock_wait
jmp 2b
3: movl %edi, %eax
call __lll_mutex_unlock_wake
jmp 4b
.size __pthread_rwlock_unlock,.-__pthread_rwlock_unlock
.globl pthread_rwlock_unlock
pthread_rwlock_unlock = __pthread_rwlock_unlock
.globl __pthread_rwlock_unlock_internal
__pthread_rwlock_unlock_internal = __pthread_rwlock_unlock
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