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/* 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. */
#include <sysdep.h>
.text
#define SYS_gettimeofday __NR_gettimeofday
#define SYS_futex 240
#define FUTEX_WAIT 0
#define FUTEX_WAKE 1
#define EAGAIN 11
#define EDEADLK 35
#define ETIMEDOUT 110
/* Offsets in the pthread_rwlock_t structure. */
#define MUTEX 0
#define NR_READERS 4
#define READERS_WAKEUP 8
#define WRITERS_WAKEUP 12
#define READERS_QUEUED 16
#define WRITERS_QUEUED 20
#define FLAGS 24
#define WRITER 28
#ifndef UP
# define LOCK lock
#else
# define LOCK
#endif
.globl __pthread_rwlock_rdlock
.type __pthread_rwlock_rdlock,@function
.align 16
__pthread_rwlock_rdlock:
pushl %esi
pushl %ebx
xorl %esi, %esi
xorl %edx, %edx
movl 12(%esp), %ebx
/* Get the lock. */
movl $1, %eax
LOCK
xaddl %eax, MUTEX(%ebx)
testl %eax, %eax
jne 1f
2: movl WRITER(%ebx), %eax
testl %eax, %eax
jne 14f
cmp $0, WRITERS_QUEUED(%ebx)
je 5f
cmpl $0, FLAGS(%ebx)
je 5f
3: incl READERS_QUEUED(%ebx)
je 4f
LOCK
decl MUTEX(%ebx)
jne 10f
11: addl $READERS_WAKEUP-MUTEX, %ebx
movl %esi, %ecx /* movl $FUTEX_WAIT, %ecx */
movl $SYS_futex, %eax
int $0x80
subl $READERS_WAKEUP-MUTEX, %ebx
/* Reget the lock. */
movl $1, %eax
LOCK
xaddl %eax, MUTEX(%ebx)
testl %eax, %eax
jne 12f
13: decl READERS_QUEUED(%ebx)
jne 2b
movl $0, READERS_WAKEUP(%ebx)
jmp 2b
5: xorl %ecx, %ecx
incl NR_READERS(%ebx)
je 8f
9: LOCK
decl MUTEX(%ebx)
jne 6f
7:
movl %ecx, %eax
popl %ebx
popl %esi
ret
1: movl %ebx, %ecx
call __lll_mutex_lock_wait
jmp 2b
14: cmpl %gs:8, %eax
jne 3b
/* Deadlock detected. */
movl $EDEADLK, %ecx
jmp 9b
6: movl %ebx, %eax
call __lll_mutex_unlock_wake
jmp 7b
/* Overflow. */
8: decl NR_READERS(%ebx)
movl $EAGAIN, %ecx
jmp 9b
/* Overflow. */
4: decl READERS_QUEUED(%ebx)
movl $EAGAIN, %ecx
jmp 9b
10: movl %ebx, %eax
call __lll_mutex_unlock_wake
jmp 11b
12: movl %ebx, %ecx
call __lll_mutex_lock_wait
jmp 13b
.size __pthread_rwlock_rdlock,.-__pthread_rwlock_rdlock
.globl pthread_rwlock_rdlock
pthread_rwlock_rdlock = __pthread_rwlock_rdlock
.globl pthread_rwlock_timedrdlock
.type pthread_rwlock_timedrdlock,@function
.align 16
pthread_rwlock_timedrdlock:
pushl %esi
pushl %edi
pushl %ebx
pushl %ebp
subl $8, %esp
movl 28(%esp), %ebp
movl 32(%esp), %edi
/* Get the lock. */
movl $1, %eax
LOCK
xaddl %eax, MUTEX(%ebp)
testl %eax, %eax
jne 1f
2: movl WRITER(%ebp), %eax
testl %eax, %eax
jne 14f
cmp $0, WRITERS_QUEUED(%ebp)
je 5f
cmpl $0, FLAGS(%ebp)
je 5f
3: incl READERS_QUEUED(%ebp)
je 4f
LOCK
decl MUTEX(%ebp)
jne 10f
/* Get current time. */
movl %esp, %ebx
xorl %ecx, %ecx
movl $SYS_gettimeofday, %eax
int $0x80
/* Compute relative timeout. */
movl 4(%esp), %eax
movl $1000, %edx
mul %edx /* Milli seconds to nano seconds. */
movl (%edi), %ecx
movl 4(%edi), %edx
subl (%esp), %ecx
subl %eax, %edx
jns 15f
addl $1000000000, %edx
decl %ecx
15: testl %ecx, %ecx
js 16f /* Time is already up. */
/* Futex call. */
movl %ecx, (%esp) /* Store relative timeout. */
movl %edx, 4(%esp)
xorl %ecx, %ecx /* movl $FUTEX_WAIT, %ecx */
movl %esp, %esi
movl %ecx, %edx
leal READERS_WAKEUP(%ebp), %ebx
movl $SYS_futex, %eax
int $0x80
movl %eax, %edx
17:
/* Reget the lock. */
movl $1, %eax
LOCK
xaddl %eax, MUTEX(%ebp)
testl %eax, %eax
jne 12f
13: cmpl $-ETIMEDOUT, %ecx
je 18f
decl READERS_QUEUED(%ebp)
jne 2b
movl $0, READERS_WAKEUP(%ebp)
jmp 2b
5: xorl %ecx, %ecx
incl NR_READERS(%ebp)
je 8f
9: LOCK
decl MUTEX(%ebp)
jne 6f
7: movl %ecx, %eax
addl $8, %esp
popl %ebp
popl %ebx
popl %edi
popl %esi
ret
1: movl %ebp, %ecx
call __lll_mutex_lock_wait
jmp 2b
14: cmpl %gs:8, %eax
jne 3b
movl $EDEADLK, %ecx
jmp 9b
6: movl %ebp, %eax
call __lll_mutex_unlock_wake
jmp 7b
/* Overflow. */
8: decl NR_READERS(%ebp)
movl $EAGAIN, %ecx
jmp 9b
/* Overflow. */
4: decl READERS_QUEUED(%ebp)
movl $EAGAIN, %ecx
jmp 9b
10: movl %ebp, %eax
call __lll_mutex_unlock_wake
jmp 11b
12: movl %ebx, %ecx
call __lll_mutex_lock_wait
jmp 13b
16: movl $-ETIMEDOUT, %ecx
jmp 17b
18: movl $ETIMEDOUT, %ecx
jmp 9b
.size pthread_rwlock_timedrdlock,.-pthread_rwlock_timedrdlock
.globl __pthread_rwlock_wrlock
.type __pthread_rwlock_wrlock,@function
.align 16
__pthread_rwlock_wrlock:
pushl %esi
pushl %ebx
xorl %esi, %esi
xorl %edx, %edx
movl 12(%esp), %ebx
/* Get the lock. */
movl $1, %eax
LOCK
xaddl %eax, MUTEX(%ebx)
testl %eax, %eax
jne 1f
2: movl WRITER(%ebx), %eax
testl %eax, %eax
jne 14f
cmp $0, NR_READERS(%ebx)
je 5f
3: incl WRITERS_QUEUED(%ebx)
je 4f
LOCK
decl MUTEX(%ebx)
jne 10f
11: addl $WRITERS_WAKEUP-MUTEX, %ebx
movl %esi, %ecx /* movl $FUTEX_WAIT, %ecx */
movl $SYS_futex, %eax
int $0x80
subl $WRITERS_WAKEUP-MUTEX, %ebx
/* Reget the lock. */
movl $1, %eax
LOCK
xaddl %eax, MUTEX(%ebx)
testl %eax, %eax
jne 12f
13: decl WRITERS_QUEUED(%ebx)
movl $0, WRITERS_WAKEUP(%ebx)
jmp 2b
5: xorl %ecx, %ecx
movl %gs:8, %eax
movl %eax, WRITER(%ebx)
9: LOCK
decl MUTEX(%ebx)
jne 6f
7:
movl %ecx, %eax
popl %ebx
popl %esi
ret
1: movl %ebx, %ecx
call __lll_mutex_lock_wait
jmp 2b
14: cmpl %gs:8, %eax
jne 3b
movl $EDEADLK, %ecx
jmp 9b
6: movl %ebx, %eax
call __lll_mutex_unlock_wake
jmp 7b
4: decl WRITERS_QUEUED(%ebx)
movl $EAGAIN, %ecx
jmp 9b
10: movl %ebx, %eax
call __lll_mutex_unlock_wake
jmp 11b
12: movl %ebx, %ecx
call __lll_mutex_lock_wait
jmp 13b
.size __pthread_rwlock_wrlock,.-__pthread_rwlock_wrlock
.globl pthread_rwlock_wrlock
pthread_rwlock_wrlock = __pthread_rwlock_wrlock
.globl pthread_rwlock_timedwrlock
.type pthread_rwlock_timedwrlock,@function
.align 16
pthread_rwlock_timedwrlock:
pushl %esi
pushl %edi
pushl %ebx
pushl %ebp
subl $8, %esp
movl 28(%esp), %ebp
movl 32(%esp), %edi
/* Get the lock. */
movl $1, %eax
LOCK
xaddl %eax, MUTEX(%ebp)
testl %eax, %eax
jne 1f
2: movl WRITER(%ebp), %eax
testl %eax, %eax
jne 14f
cmp $0, NR_READERS(%ebp)
je 5f
3: incl WRITERS_QUEUED(%ebp)
je 4f
LOCK
decl MUTEX(%ebp)
jne 10f
/* Get current time. */
movl %esp, %ebx
xorl %ecx, %ecx
movl $SYS_gettimeofday, %eax
int $0x80
/* Compute relative timeout. */
movl 4(%esp), %eax
movl $1000, %edx
mul %edx /* Milli seconds to nano seconds. */
movl (%edi), %ecx
movl 4(%edi), %edx
subl (%esp), %ecx
subl %eax, %edx
jns 15f
addl $1000000000, %edx
decl %ecx
15: testl %ecx, %ecx
js 16f /* Time is already up. */
/* Futex call. */
movl %ecx, (%esp) /* Store relative timeout. */
movl %edx, 4(%esp)
xorl %ecx, %ecx /* movl $FUTEX_WAIT, %ecx */
movl %esp, %esi
movl %ecx, %edx
leal WRITERS_WAKEUP(%ebp), %ebx
movl $SYS_futex, %eax
int $0x80
movl %eax, %edx
17:
/* Reget the lock. */
movl $1, %eax
LOCK
xaddl %eax, MUTEX(%ebp)
testl %eax, %eax
jne 12f
13: cmpl $-ETIMEDOUT, %ecx
je 18f
decl WRITERS_QUEUED(%ebp)
movl $0, WRITERS_WAKEUP(%ebp)
jmp 2b
5: xorl %ecx, %ecx
movl %gs:8, %eax
movl %eax, WRITER(%ebp)
9: LOCK
decl MUTEX(%ebp)
jne 6f
7: movl %ecx, %eax
addl $8, %esp
popl %ebp
popl %ebx
popl %edi
popl %esi
ret
1: movl %ebp, %ecx
call __lll_mutex_lock_wait
jmp 2b
14: cmpl %gs:8, %eax
jne 3b
movl $EDEADLK, %ecx
jmp 9b
6: movl %ebp, %eax
call __lll_mutex_unlock_wake
jmp 7b
/* Overflow. */
4: decl WRITERS_QUEUED(%ebp)
movl $EAGAIN, %ecx
jmp 9b
10: movl %ebp, %eax
call __lll_mutex_unlock_wake
jmp 11b
12: movl %ebx, %ecx
call __lll_mutex_lock_wait
jmp 13b
16: movl $-ETIMEDOUT, %ecx
jmp 17b
18: movl $ETIMEDOUT, %ecx
jmp 9b
.size pthread_rwlock_timedwrlock,.-pthread_rwlock_timedwrlock
.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
xaddl %eax, MUTEX(%edi)
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
int $0x80
6: LOCK
decl MUTEX(%edi)
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
|