summaryrefslogtreecommitdiff
path: root/nptl/sysdeps/unix/sysv/linux/i386/i486/pthread_cond_broadcast.S
blob: f46b4b874abdb32b9ca97444a6bceaa403ad8bf7 (plain)
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
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
/* Copyright (C) 2002, 2003, 2004, 2006, 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 <sysdep.h>
#include <shlib-compat.h>
#include <lowlevellock.h>
#include <lowlevelcond.h>
#include <kernel-features.h>
#include <pthread-pi-defines.h>
#include <pthread-errnos.h>

	.text

	/* int pthread_cond_broadcast (pthread_cond_t *cond) */
	.globl	__pthread_cond_broadcast
	.type	__pthread_cond_broadcast, @function
	.align	16
__pthread_cond_broadcast:
	cfi_startproc
	pushl	%ebx
	cfi_adjust_cfa_offset(4)
	pushl	%esi
	cfi_adjust_cfa_offset(4)
	pushl	%edi
	cfi_adjust_cfa_offset(4)
	pushl	%ebp
	cfi_adjust_cfa_offset(4)
	cfi_offset(%ebx, -8)
	cfi_offset(%esi, -12)
	cfi_offset(%edi, -16)
	cfi_offset(%ebp, -20)

	movl	20(%esp), %ebx

	/* Get internal lock.  */
	movl	$1, %edx
	xorl	%eax, %eax
	LOCK
#if cond_lock == 0
	cmpxchgl %edx, (%ebx)
#else
	cmpxchgl %edx, cond_lock(%ebx)
#endif
	jnz	1f

2:	addl	$cond_futex, %ebx
	movl	total_seq+4-cond_futex(%ebx), %eax
	movl	total_seq-cond_futex(%ebx), %ebp
	cmpl	wakeup_seq+4-cond_futex(%ebx), %eax
	ja	3f
	jb	4f
	cmpl	wakeup_seq-cond_futex(%ebx), %ebp
	jna	4f

	/* Cause all currently waiting threads to recognize they are
	   woken up.  */
3:	movl	%ebp, wakeup_seq-cond_futex(%ebx)
	movl	%eax, wakeup_seq-cond_futex+4(%ebx)
	movl	%ebp, woken_seq-cond_futex(%ebx)
	movl	%eax, woken_seq-cond_futex+4(%ebx)
	addl	%ebp, %ebp
	addl	$1, broadcast_seq-cond_futex(%ebx)
	movl	%ebp, (%ebx)

	/* Get the address of the mutex used.  */
	movl	dep_mutex-cond_futex(%ebx), %edi

	/* Unlock.  */
	LOCK
	subl	$1, cond_lock-cond_futex(%ebx)
	jne	7f

	/* Don't use requeue for pshared condvars.  */
8:	cmpl	$-1, %edi
	je	9f

	/* XXX: The kernel so far doesn't support requeue to PI futex.  */
	/* XXX: The kernel only supports FUTEX_CMP_REQUEUE to the same
	   type of futex (private resp. shared).  */
	testl	$(PI_BIT | PS_BIT), MUTEX_KIND(%edi)
	jne	9f

	/* Wake up all threads.  */
#ifdef __ASSUME_PRIVATE_FUTEX
	movl	$(FUTEX_CMP_REQUEUE|FUTEX_PRIVATE_FLAG), %ecx
#else
	movl	%gs:PRIVATE_FUTEX, %ecx
	orl	$FUTEX_CMP_REQUEUE, %ecx
#endif
	movl	$SYS_futex, %eax
	movl	$0x7fffffff, %esi
	movl	$1, %edx
	/* Get the address of the futex involved.  */
# if MUTEX_FUTEX != 0
	addl	$MUTEX_FUTEX, %edi
# endif
/* FIXME: Until Ingo fixes 4G/4G vDSO, 6 arg syscalls are broken for sysenter.
	ENTER_KERNEL  */
	int	$0x80

	/* For any kind of error, which mainly is EAGAIN, we try again
	   with WAKE.  The general test also covers running on old
	   kernels.  */
	cmpl	$0xfffff001, %eax
	jae	9f

10:	xorl	%eax, %eax
	popl	%ebp
	cfi_adjust_cfa_offset(-4)
	cfi_restore(%ebp)
	popl	%edi
	cfi_adjust_cfa_offset(-4)
	cfi_restore(%edi)
	popl	%esi
	cfi_adjust_cfa_offset(-4)
	cfi_restore(%esi)
	popl	%ebx
	cfi_adjust_cfa_offset(-4)
	cfi_restore(%ebx)
	ret

	cfi_adjust_cfa_offset(16)
	cfi_offset(%ebx, -8)
	cfi_offset(%esi, -12)
	cfi_offset(%edi, -16)
	cfi_offset(%ebp, -20)
	.align	16
	/* Unlock.  */
4:	LOCK
	subl	$1, cond_lock-cond_futex(%ebx)
	jne	5f

6:	xorl	%eax, %eax
	popl	%ebp
	cfi_adjust_cfa_offset(-4)
	cfi_restore(%ebp)
	popl	%edi
	cfi_adjust_cfa_offset(-4)
	cfi_restore(%edi)
	popl	%esi
	cfi_adjust_cfa_offset(-4)
	cfi_restore(%esi)
	popl	%ebx
	cfi_adjust_cfa_offset(-4)
	cfi_restore(%ebx)
	ret

	cfi_adjust_cfa_offset(16)
	cfi_offset(%ebx, -8)
	cfi_offset(%esi, -12)
	cfi_offset(%edi, -16)
	cfi_offset(%ebp, -20)
	/* Initial locking failed.  */
1:
#if cond_lock == 0
	movl	%ebx, %edx
#else
	leal	cond_lock(%ebx), %edx
#endif
#if (LLL_SHARED-LLL_PRIVATE) > 255
	xorl	%ecx, %ecx
#endif
	cmpl	$-1, dep_mutex(%ebx)
	setne	%cl
	subl	$1, %ecx
	andl	$(LLL_SHARED-LLL_PRIVATE), %ecx
#if LLL_PRIVATE != 0
	addl	$LLL_PRIVATE, %ecx
#endif
	call	__lll_lock_wait
	jmp	2b

	/* Unlock in loop requires waekup.  */
5:	leal	cond_lock-cond_futex(%ebx), %eax
#if (LLL_SHARED-LLL_PRIVATE) > 255
	xorl	%ecx, %ecx
#endif
	cmpl	$-1, dep_mutex-cond_futex(%ebx)
	setne	%cl
	subl	$1, %ecx
	andl	$(LLL_SHARED-LLL_PRIVATE), %ecx
#if LLL_PRIVATE != 0
	addl	$LLL_PRIVATE, %ecx
#endif
	call	__lll_unlock_wake
	jmp	6b

	/* Unlock in loop requires waekup.  */
7:	leal	cond_lock-cond_futex(%ebx), %eax
#if (LLL_SHARED-LLL_PRIVATE) > 255
	xorl	%ecx, %ecx
#endif
	cmpl	$-1, dep_mutex-cond_futex(%ebx)
	setne	%cl
	subl	$1, %ecx
	andl	$(LLL_SHARED-LLL_PRIVATE), %ecx
#if LLL_PRIVATE != 0
	addl	$LLL_PRIVATE, %ecx
#endif
	call	__lll_unlock_wake
	jmp	8b

9:	/* The futex requeue functionality is not available.  */
	movl	$0x7fffffff, %edx
#if FUTEX_PRIVATE_FLAG > 255
	xorl	%ecx, %ecx
#endif
	cmpl	$-1, dep_mutex-cond_futex(%ebx)
	sete	%cl
	subl	$1, %ecx
#ifdef __ASSUME_PRIVATE_FUTEX
	andl	$FUTEX_PRIVATE_FLAG, %ecx
#else
	andl	%gs:PRIVATE_FUTEX, %ecx
#endif
	addl	$FUTEX_WAKE, %ecx
	movl	$SYS_futex, %eax
	ENTER_KERNEL
	jmp	10b
	cfi_endproc
	.size	__pthread_cond_broadcast, .-__pthread_cond_broadcast
versioned_symbol (libpthread, __pthread_cond_broadcast, pthread_cond_broadcast,
		  GLIBC_2_3_2)