[thirdparty/glibc.git] / sysdeps / unix / sysv / linux / x86_64 / pthread_rwlock_wrlock.S

/* Copyright (C) 2002-2014 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, see
   <http://www.gnu.org/licenses/>.  */

#include <sysdep.h>
#include <lowlevellock.h>
#include <lowlevelrwlock.h>
#include <pthread-errnos.h>
#include <kernel-features.h>
#include <stap-probe.h>

	.text

	.globl	__pthread_rwlock_wrlock
	.type	__pthread_rwlock_wrlock,@function
	.align	16
__pthread_rwlock_wrlock:
	cfi_startproc

	LIBC_PROBE (wrlock_entry, 1, %rdi)

	xorq	%r10, %r10

	/* Get the lock.  */
	movl	$1, %esi
	xorl	%eax, %eax
	LOCK
#if MUTEX == 0
	cmpxchgl %esi, (%rdi)
#else
	cmpxchgl %esi, MUTEX(%rdi)
#endif
	jnz	1f

2:	movl	WRITER(%rdi), %eax
	testl	%eax, %eax
	jne	14f
	cmpl	$0, NR_READERS(%rdi)
	je	5f

3:	incl	WRITERS_QUEUED(%rdi)
	je	4f

	movl	WRITERS_WAKEUP(%rdi), %edx

	LOCK
#if MUTEX == 0
	decl	(%rdi)
#else
	decl	MUTEX(%rdi)
#endif
	jne	10f

11:
#ifdef __ASSUME_PRIVATE_FUTEX
	movl	$FUTEX_PRIVATE_FLAG|FUTEX_WAIT, %esi
	xorl	PSHARED(%rdi), %esi
#else
# if FUTEX_WAIT == 0
	movl	PSHARED(%rdi), %esi
# else
	movl	$FUTEX_WAIT, %esi
	orl	PSHARED(%rdi), %esi
# endif
	xorl	%fs:PRIVATE_FUTEX, %esi
#endif
	addq	$WRITERS_WAKEUP, %rdi
	movl	$SYS_futex, %eax
	syscall

	subq	$WRITERS_WAKEUP, %rdi

	/* Reget the lock.  */
	movl	$1, %esi
	xorl	%eax, %eax
	LOCK
#if MUTEX == 0
	cmpxchgl %esi, (%rdi)
#else
	cmpxchgl %esi, MUTEX(%rdi)
#endif
	jnz	12f

13:	decl	WRITERS_QUEUED(%rdi)
	jmp	2b

5:	xorl	%edx, %edx
	movl	%fs:TID, %eax
	movl	%eax, WRITER(%rdi)
9:	LOCK
#if MUTEX == 0
	decl	(%rdi)
#else
	decl	MUTEX(%rdi)
#endif
	jne	6f
7:

	movq	%rdx, %rax
	retq

1:	movl	PSHARED(%rdi), %esi
#if MUTEX != 0
	addq	$MUTEX, %rdi
#endif
	callq	__lll_lock_wait
#if MUTEX != 0
	subq	$MUTEX, %rdi
#endif
	jmp	2b

14:	cmpl	%fs:TID, %eax
	jne	3b
	movl	$EDEADLK, %edx
	jmp	9b

6:	movl	PSHARED(%rdi), %esi
#if MUTEX != 0
	addq	$MUTEX, %rdi
#endif
	callq	__lll_unlock_wake
	jmp	7b

4:	decl	WRITERS_QUEUED(%rdi)
	movl	$EAGAIN, %edx
	jmp	9b

10:	movl	PSHARED(%rdi), %esi
#if MUTEX != 0
	addq	$MUTEX, %rdi
#endif
	callq	__lll_unlock_wake
#if MUTEX != 0
	subq	$MUTEX, %rdi
#endif
	jmp	11b

12:	movl	PSHARED(%rdi), %esi
#if MUTEX != 0
	addq	$MUTEX, %rdi
#endif
	callq	__lll_lock_wait
#if MUTEX != 0
	subq	$MUTEX, %rdi
#endif
	jmp	13b
	cfi_endproc
	.size	__pthread_rwlock_wrlock,.-__pthread_rwlock_wrlock

strong_alias (__pthread_rwlock_wrlock, pthread_rwlock_wrlock)
hidden_def (__pthread_rwlock_wrlock)
Commit	Line	Data
d4697bc9	1	/* Copyright (C) 2002-2014 Free Software Foundation, Inc.
da49194d UD	2	This file is part of the GNU C Library.
	3	Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
	4
	5	The GNU C Library is free software; you can redistribute it and/or
	6	modify it under the terms of the GNU Lesser General Public
	7	License as published by the Free Software Foundation; either
	8	version 2.1 of the License, or (at your option) any later version.
	9
	10	The GNU C Library is distributed in the hope that it will be useful,
	11	but WITHOUT ANY WARRANTY; without even the implied warranty of
	12	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	13	Lesser General Public License for more details.
	14
	15	You should have received a copy of the GNU Lesser General Public
59ba27a6 PE	16	License along with the GNU C Library; if not, see
59ba27a6 PE	17	<http://www.gnu.org/licenses/>. */
da49194d UD	18
da49194d UD	19	#include <sysdep.h>
e51deae7	20	#include <lowlevellock.h>
da49194d	21	#include <lowlevelrwlock.h>
326132db	22	#include <pthread-errnos.h>
28635aca	23	#include <kernel-features.h>
5acf7263	24	#include <stap-probe.h>
da49194d	25
da49194d UD	26	.text
	27
	28	.globl __pthread_rwlock_wrlock
	29	.type __pthread_rwlock_wrlock,@function
	30	.align 16
	31	__pthread_rwlock_wrlock:
1bc2b97e	32	cfi_startproc
5acf7263 RM	33
	34	LIBC_PROBE (wrlock_entry, 1, %rdi)
	35
da49194d UD	36	xorq %r10, %r10
	37
	38	/* Get the lock. */
	39	movl $1, %esi
3a226d33	40	xorl %eax, %eax
da49194d UD	41	LOCK
da49194d UD	42	#if MUTEX == 0
3a226d33	43	cmpxchgl %esi, (%rdi)
da49194d	44	#else
3a226d33	45	cmpxchgl %esi, MUTEX(%rdi)
da49194d	46	#endif
3a226d33	47	jnz 1f
da49194d	48
4ad0bbf4 UD	49	2: movl WRITER(%rdi), %eax
4ad0bbf4 UD	50	testl %eax, %eax
da49194d UD	51	jne 14f
	52	cmpl $0, NR_READERS(%rdi)
	53	je 5f
	54
	55	3: incl WRITERS_QUEUED(%rdi)
	56	je 4f
	57
	58	movl WRITERS_WAKEUP(%rdi), %edx
	59
	60	LOCK
	61	#if MUTEX == 0
	62	decl (%rdi)
	63	#else
	64	decl MUTEX(%rdi)
	65	#endif
	66	jne 10f
	67
50f1dec5	68	11:
28635aca	69	#ifdef __ASSUME_PRIVATE_FUTEX
50f1dec5 UD	70	movl $FUTEX_PRIVATE_FLAG\|FUTEX_WAIT, %esi
50f1dec5 UD	71	xorl PSHARED(%rdi), %esi
ee618985	72	#else
50f1dec5 UD	73	# if FUTEX_WAIT == 0
	74	movl PSHARED(%rdi), %esi
	75	# else
ee618985	76	movl $FUTEX_WAIT, %esi
50f1dec5 UD	77	orl PSHARED(%rdi), %esi
	78	# endif
	79	xorl %fs:PRIVATE_FUTEX, %esi
ee618985	80	#endif
50f1dec5	81	addq $WRITERS_WAKEUP, %rdi
ee618985	82	movl $SYS_futex, %eax
da49194d UD	83	syscall
da49194d UD	84
46a32546	85	subq $WRITERS_WAKEUP, %rdi
da49194d UD	86
	87	/* Reget the lock. */
	88	movl $1, %esi
3a226d33	89	xorl %eax, %eax
da49194d UD	90	LOCK
da49194d UD	91	#if MUTEX == 0
3a226d33	92	cmpxchgl %esi, (%rdi)
da49194d	93	#else
3a226d33	94	cmpxchgl %esi, MUTEX(%rdi)
da49194d	95	#endif
3a226d33	96	jnz 12f
da49194d UD	97
	98	13: decl WRITERS_QUEUED(%rdi)
	99	jmp 2b
	100
ee618985	101	5: xorl %edx, %edx
4ad0bbf4 UD	102	movl %fs:TID, %eax
4ad0bbf4 UD	103	movl %eax, WRITER(%rdi)
da49194d UD	104	9: LOCK
	105	#if MUTEX == 0
	106	decl (%rdi)
	107	#else
46a32546	108	decl MUTEX(%rdi)
da49194d UD	109	#endif
	110	jne 6f
	111	7:
	112
92ed3daf	113	movq %rdx, %rax
da49194d UD	114	retq
da49194d UD	115
e51deae7	116	1: movl PSHARED(%rdi), %esi
da49194d UD	117	#if MUTEX != 0
	118	addq $MUTEX, %rdi
	119	#endif
e51deae7	120	callq __lll_lock_wait
da49194d UD	121	#if MUTEX != 0
	122	subq $MUTEX, %rdi
	123	#endif
	124	jmp 2b
	125
4ad0bbf4	126	14: cmpl %fs:TID, %eax
da49194d	127	jne 3b
ee618985	128	movl $EDEADLK, %edx
da49194d UD	129	jmp 9b
da49194d UD	130
e51deae7	131	6: movl PSHARED(%rdi), %esi
da49194d UD	132	#if MUTEX != 0
	133	addq $MUTEX, %rdi
	134	#endif
e51deae7	135	callq __lll_unlock_wake
da49194d UD	136	jmp 7b
	137
	138	4: decl WRITERS_QUEUED(%rdi)
92ed3daf	139	movl $EAGAIN, %edx
da49194d UD	140	jmp 9b
da49194d UD	141
e51deae7	142	10: movl PSHARED(%rdi), %esi
da49194d UD	143	#if MUTEX != 0
	144	addq $MUTEX, %rdi
	145	#endif
e51deae7	146	callq __lll_unlock_wake
da49194d UD	147	#if MUTEX != 0
	148	subq $MUTEX, %rdi
	149	#endif
	150	jmp 11b
	151
e51deae7	152	12: movl PSHARED(%rdi), %esi
da49194d UD	153	#if MUTEX != 0
	154	addq $MUTEX, %rdi
	155	#endif
e51deae7	156	callq __lll_lock_wait
da49194d UD	157	#if MUTEX != 0
	158	subq $MUTEX, %rdi
	159	#endif
	160	jmp 13b
1bc2b97e	161	cfi_endproc
da49194d UD	162	.size __pthread_rwlock_wrlock,.-__pthread_rwlock_wrlock
da49194d UD	163
4d17e683 AS	164	strong_alias (__pthread_rwlock_wrlock, pthread_rwlock_wrlock)
4d17e683 AS	165	hidden_def (__pthread_rwlock_wrlock)