1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
|
/* 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"
|