glibc/nptl/sysdeps/unix/sysv/linux/i386/i486/libc-lowlevellock.S
Ulrich Drepper 5a8075b116 * init.c (__pthread_initialize_minimal_internal): Check whether
private futexes are available.
	* allocatestack.c (allocate_stack): Copy private_futex field from
	current thread into the new stack.
	* sysdeps/unix/sysv/linux/x86_64/libc-lowlevellock.S: Use private
	futexes if they are available.
	* sysdeps/unix/sysv/linux/i386/i486/libc-lowlevellock.S: Likewise
	* sysdeps/unix/sysv/linux/x86_64/lowlevellock.S: Adjust so that change
	in libc-lowlevellock.S allow using private futexes.
	* sysdeps/unix/sysv/linux/i386/i486/lowlevellock.S: Likewise.
	* sysdeps/unix/sysv/linux/x86_64/lowlevellock.h: Define
	FUTEX_PRIVATE_FLAG.
	* sysdeps/unix/sysv/linux/i386/lowlevellock.h: Likewise.
	* sysdeps/unix/sysv/linux/x86_64/pthread_once.S: Use private futexes
	if they are available.
	* sysdeps/unix/sysv/linux/i386/pthread_once.S: Likewise.
	* sysdeps/x86_64/tcb-offsets.sym: Add PRIVATE_FUTEX.
	* sysdeps/i386/tcb-offsets.sym: Likewise.
	* sysdeps/x86_64/tls.h (tcbhead_t): Add private_futex field.
	* sysdeps/i386/tls.h (tcbhead_t): Likewise.
2007-05-23 20:51:45 +00:00

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1.6 KiB
ArmAsm

/* Copyright (C) 2002, 2003, 2007 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 <kernel-features.h>
/* In libc.so we do not unconditionally use the lock prefix. Only if
the application is using threads. */
#ifndef UP
# define LOCK \
cmpl $0, %gs:MULTIPLE_THREADS_OFFSET; \
je 0f; \
lock; \
0:
#endif
/* All locks in libc are private. Use the kernel feature if possible. */
#define FUTEX_PRIVATE_FLAG 128
#ifdef __ASSUME_PRIVATE_FUTEX
# define FUTEX_WAIT (0 | FUTEX_PRIVATE_FLAG)
# define FUTEX_WAKE (1 | FUTEX_PRIVATE_FLAG)
#else
# define LOAD_FUTEX_WAIT(reg) \
movl %gs:PRIVATE_FUTEX, reg
# define LOAD_FUTEX_WAKE(reg) \
movl %gs:PRIVATE_FUTEX, reg ; \
orl $FUTEX_WAKE, reg
#endif
#include "lowlevellock.S"