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
|
/* Copyright (C) 2002 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. */
#ifndef _LOWLEVELSEM_H
#define _LOWLEVELSEM_H 1
#ifndef LOCK
# ifdef UP
# define LOCK /* nothing */
# else
# define LOCK "lock;"
# endif
#endif
#define SYS_futex 240
#define lll_sem_wait(sem) \
({ int result, ignore1, ignore2; \
__asm __volatile ("1:\tincl 8(%4)\n\t" \
LOCK "incl (%4)\n\t" \
"jng 2f\n" \
".subsection 1\n" \
"2:\tmovl %4, %%eax\n\t" \
"call __lll_unlock_wake\n\t" \
"jmp 3f\n\t" \
".previous\n" \
"3:\tpushl %%ebx\n\t" \
"movl %%esi, %%ecx\n\t" \
"movl %%esi, %%edx\n\t" \
"leal 4(%4), %%ebx\n\t" \
"movl %5, %%eax\n\t" \
"int $0x80\n\t" \
"movl %%eax, %%edx\n\t" \
"popl %%ebx\n\t" \
"orl $-1, %%eax\n\t" \
LOCK "xaddl %%eax, (%4)\n\t" \
"jne 4f\n\t" \
".subsection 1\n" \
"4:\tmovl %4, %%ecx\n\t" \
"call __lll_lock_wait\n\t" \
"jmp 5f\n\t" \
".previous\n" \
"5:\tdecl 8(%4)\n\t" \
"xorl %0, %0\n\t" \
"cmpl $0, 4(%4)\n\t" \
"jne,pt 6f\n\t" \
"cmpl %7, %%edx\n\t" \
"jne,pn 1b\n\t" \
"addl %8, %0\n\t" /* Shorter than movl %7, %0 */ \
"6:" \
: "=a" (result), "=c" (ignore1), "=d" (ignore2), \
"=m" (*sem) \
: "D" (sem), "i" (SYS_futex), "S" (0), \
"i" (-EINTR), "i" (EINTR)); \
result; })
extern int __lll_sem_timedwait (struct sem *sem, const struct timespec *ts)
__attribute__ ((regparm (2))) attribute_hidden;
#define lll_sem_timedwait(sem, timeout) \
__lll_sem_timedwait (sem, timeout)
#define lll_sem_post(sem) \
(void) ({ int ignore1, ignore2, ignore3; \
__asm __volatile ("movl $1, %%eax\n\t" \
LOCK \
"xaddl %%eax, (%4)\n\t" \
"pushl %%esi\n\t" \
"pushl %%ebx\n\t" \
"movl %4, %%ebx\n\t" \
"leal 1(%%eax), %%edx\n\t" \
"xorl %%esi, %%esi\n\t" \
"movl %5, %%eax\n\t" \
/* movl $FUTEX_WAKE, %ecx */ \
"movl $1, %%ecx\n\t" \
"int $0x80\n\t" \
"popl %%ebx\n\t" \
"popl %%esi" \
: "=&a" (ignore1), "=c" (ignore2), \
"=m" (*sem), "=d" (ignore3) \
: "r" (sem), "i" (SYS_futex)); })
#endif /* lowlevelsem.h */
|
