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

/* 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 <shlib-compat.h>
#include <lowlevelcond.h>
#include <kernel-features.h>

#ifdef UP
# define LOCK
#else
# define LOCK lock
#endif

#define SYS_futex		202
#define FUTEX_WAIT		0
#define FUTEX_WAKE		1
#define FUTEX_REQUEUE		3

#define EINVAL			22


	.text

	/* int pthread_cond_signal (pthread_cond_t *cond) */
	.globl	__pthread_cond_signal
	.type	__pthread_cond_signal, @function
	.align	16
__pthread_cond_signal:

	/* Get internal lock.  */
	movq	%rdi, %r8
	movl	$1, %esi
	LOCK
#if cond_lock == 0
	xaddl	%esi, (%rdi)
#else
	xaddl	%esi, cond_lock(%rdi)
#endif
	testl	%esi, %esi
	jne	1f

2:	addq	$wakeup_seq, %rdi
	movq	total_seq(%r8), %rcx
	cmpq	(%rdi), %rcx
	jbe	4f

	/* Bump the wakeup number.  */
	addq	$1, (%rdi)

	/* Wake up one thread.  */
	movq	$FUTEX_REQUEUE, %rsi
	movq	$SYS_futex, %rax
	xorq	%rdx, %rdx
	movq	$1, %r10
	syscall

#ifndef __ASSUME_FUTEX_REQUEUE
	cmpq	$-EINVAL, %rax
	je	7f
#endif

	/* If we moved a thread we in any case have to make the syscall.  */
	testq	%rax, %rax
	jne	5f

	/* Unlock.  */
4:	LOCK
#if cond_lock == 0
	decl	(%r8)
#else
	decl	cond_lock(%r8)
#endif
	jne	5f

6:	xorl	%eax, %eax
	retq

	/* Initial locking failed.  */
1:
#if cond_lock != 0
	addq	$cond_lock, %rdi
#endif
	callq	__lll_mutex_lock_wait
#if cond_lock != 0
	subq	$cond_lock, %rdi
#endif
	jmp	2b

	/* Unlock in loop requires wakeup.  */
5:
#if cond_lock != 0
	addq	$cond_lock-wakeup_seq, %rdi
#else
	movq	%r8, %rdi
#endif
	callq	__lll_mutex_unlock_wake
	jmp	6b

#ifndef __ASSUME_FUTEX_REQUEUE
7:	/* The futex requeue functionality is not available.  */
	movq	$1, %rdx
	movq	$FUTEX_WAKE, %rsi
	movq	$SYS_futex, %rax
	syscall
	jmp	4b
#endif
	.size	__pthread_cond_signal, .-__pthread_cond_signal
versioned_symbol (libpthread, __pthread_cond_signal, pthread_cond_signal,
		  GLIBC_2_3_2)
Commit	Line	Data
d0aacb47 UD	1	/* Copyright (C) 2002, 2003 Free Software Foundation, Inc.
	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
	16	License along with the GNU C Library; if not, write to the Free
	17	Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
	18	02111-1307 USA. */
	19
	20	#include <sysdep.h>
	21	#include <shlib-compat.h>
	22	#include <lowlevelcond.h>
69431c9a	23	#include <kernel-features.h>
d0aacb47 UD	24
	25	#ifdef UP
	26	# define LOCK
	27	#else
	28	# define LOCK lock
	29	#endif
	30
	31	#define SYS_futex 202
	32	#define FUTEX_WAIT 0
	33	#define FUTEX_WAKE 1
69431c9a UD	34	#define FUTEX_REQUEUE 3
	35
	36	#define EINVAL 22
d0aacb47 UD	37
	38
	39	.text
	40
	41	/* int pthread_cond_signal (pthread_cond_t cond) /
	42	.globl __pthread_cond_signal
	43	.type __pthread_cond_signal, @function
	44	.align 16
	45	__pthread_cond_signal:
	46
	47	/* Get internal lock. */
7661d9f7	48	movq %rdi, %r8
d0aacb47 UD	49	movl $1, %esi
	50	LOCK
	51	#if cond_lock == 0
7661d9f7	52	xaddl %esi, (%rdi)
d0aacb47	53	#else
7661d9f7	54	xaddl %esi, cond_lock(%rdi)
d0aacb47 UD	55	#endif
	56	testl %esi, %esi
	57	jne 1f
	58
7661d9f7	59	2: addq $wakeup_seq, %rdi
69431c9a	60	movq total_seq(%r8), %rcx
d0aacb47 UD	61	cmpq (%rdi), %rcx
	62	jbe 4f
	63
	64	/* Bump the wakeup number. */
	65	addq $1, (%rdi)
	66
	67	/* Wake up one thread. */
7661d9f7	68	movq $FUTEX_REQUEUE, %rsi
d0aacb47	69	movq $SYS_futex, %rax
69431c9a UD	70	xorq %rdx, %rdx
69431c9a UD	71	movq $1, %r10
d0aacb47 UD	72	syscall
d0aacb47 UD	73
69431c9a UD	74	#ifndef __ASSUME_FUTEX_REQUEUE
	75	cmpq $-EINVAL, %rax
	76	je 7f
	77	#endif
	78
	79	/* If we moved a thread we in any case have to make the syscall. */
	80	testq %rax, %rax
	81	jne 5f
	82
d0aacb47 UD	83	/* Unlock. */
d0aacb47 UD	84	4: LOCK
7661d9f7 UD	85	#if cond_lock == 0
	86	decl (%r8)
	87	#else
69431c9a	88	decl cond_lock(%r8)
7661d9f7	89	#endif
d0aacb47 UD	90	jne 5f
	91
	92	6: xorl %eax, %eax
	93	retq
	94
	95	/* Initial locking failed. */
	96	1:
	97	#if cond_lock != 0
	98	addq $cond_lock, %rdi
	99	#endif
6c477888	100	callq __lll_mutex_lock_wait
d0aacb47 UD	101	#if cond_lock != 0
	102	subq $cond_lock, %rdi
	103	#endif
	104	jmp 2b
	105
7661d9f7	106	/* Unlock in loop requires wakeup. */
69431c9a UD	107	5:
	108	#if cond_lock != 0
	109	addq $cond_lock-wakeup_seq, %rdi
	110	#else
	111	movq %r8, %rdi
	112	#endif
6c477888	113	callq __lll_mutex_unlock_wake
d0aacb47	114	jmp 6b
69431c9a UD	115
	116	#ifndef __ASSUME_FUTEX_REQUEUE
	117	7: /* The futex requeue functionality is not available. */
	118	movq $1, %rdx
7661d9f7	119	movq $FUTEX_WAKE, %rsi
69431c9a UD	120	movq $SYS_futex, %rax
	121	syscall
	122	jmp 4b
7661d9f7	123	#endif
d0aacb47 UD	124	.size __pthread_cond_signal, .-__pthread_cond_signal
	125	versioned_symbol (libpthread, __pthread_cond_signal, pthread_cond_signal,
	126	GLIBC_2_3_2)