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
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
|
/* Copyright (C) 2002, 2003, 2004, 2005 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 240
#define FUTEX_WAIT 0
#define FUTEX_WAKE 1
#define FUTEX_WAKE_OP 5
#define FUTEX_OP_CLEAR_WAKE_IF_GT_ONE ((4 << 24) | 1)
#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:
pushl %ebx
pushl %edi
movl 12(%esp), %edi
/* Get internal lock. */
movl $1, %edx
xorl %eax, %eax
LOCK
#if cond_lock == 0
cmpxchgl %edx, (%edi)
#else
cmpxchgl %edx, cond_lock(%edi)
#endif
jnz 1f
2: leal cond_futex(%edi), %ebx
movl total_seq+4(%edi), %eax
movl total_seq(%edi), %ecx
cmpl wakeup_seq+4(%edi), %eax
#if cond_lock != 0
/* Must use leal to preserve the flags. */
leal cond_lock(%edi), %edi
#endif
ja 3f
jb 4f
cmpl wakeup_seq-cond_futex(%ebx), %ecx
jbe 4f
/* Bump the wakeup number. */
3: addl $1, wakeup_seq-cond_futex(%ebx)
adcl $0, wakeup_seq-cond_futex+4(%ebx)
addl $1, (%ebx)
/* Wake up one thread. */
pushl %esi
pushl %ebp
movl $FUTEX_WAKE_OP, %ecx
movl $SYS_futex, %eax
movl $1, %edx
movl $1, %esi
movl $FUTEX_OP_CLEAR_WAKE_IF_GT_ONE, %ebp
/* FIXME: Until Ingo fixes 4G/4G vDSO, 6 arg syscalls are broken for
sysenter.
ENTER_KERNEL */
int $0x80
popl %ebp
popl %esi
/* For any kind of error, we try again with WAKE.
The general test also covers running on old kernels. */
cmpl $-4095, %eax
jae 7f
6: xorl %eax, %eax
popl %edi
popl %ebx
ret
7: movl $FUTEX_WAKE, %ecx
movl $SYS_futex, %eax
/* %edx should be 1 already from $FUTEX_WAKE_OP syscall.
movl $1, %edx */
ENTER_KERNEL
/* Unlock. Note that at this point %edi always points to
cond_lock. */
4: LOCK
subl $1, (%edi)
je 6b
/* Unlock in loop requires wakeup. */
5: movl %edi, %eax
call __lll_mutex_unlock_wake
jmp 6b
/* Initial locking failed. */
1:
#if cond_lock == 0
movl %edi, %ecx
#else
leal cond_lock(%edi), %ecx
#endif
call __lll_mutex_lock_wait
jmp 2b
.size __pthread_cond_signal, .-__pthread_cond_signal
versioned_symbol (libpthread, __pthread_cond_signal, pthread_cond_signal,
GLIBC_2_3_2)
|
