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
|
/*
* Copyright (c) 1995-1998 John Birrell <jb@cimlogic.com.au>.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by John Birrell.
* 4. Neither the name of the author nor the names of any co-contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#include <errno.h>
#include <pthread.h>
#include "pthread_private.h"
static void finish_suspension(void *arg);
__weak_reference(_pthread_suspend_np, pthread_suspend_np);
/* Suspend a thread: */
int
_pthread_suspend_np(pthread_t thread)
{
int ret;
/* Find the thread in the list of active threads: */
if ((ret = _find_thread(thread)) == 0) {
/*
* Defer signals to protect the scheduling queues from
* access by the signal handler:
*/
_thread_kern_sig_defer();
switch (thread->state) {
case PS_RUNNING:
/*
* Remove the thread from the priority queue and
* set the state to suspended:
*/
PTHREAD_PRIOQ_REMOVE(thread);
PTHREAD_SET_STATE(thread, PS_SUSPENDED);
break;
case PS_SPINBLOCK:
case PS_FDR_WAIT:
case PS_FDW_WAIT:
case PS_POLL_WAIT:
case PS_SELECT_WAIT:
/*
* Remove these threads from the work queue
* and mark the operation as interrupted:
*/
if ((thread->flags & PTHREAD_FLAGS_IN_WORKQ) != 0)
PTHREAD_WORKQ_REMOVE(thread);
_thread_seterrno(thread,EINTR);
/* FALLTHROUGH */
case PS_SLEEP_WAIT:
thread->interrupted = 1;
/* FALLTHROUGH */
case PS_SIGTHREAD:
case PS_WAIT_WAIT:
case PS_SIGSUSPEND:
case PS_SIGWAIT:
/*
* Remove these threads from the waiting queue and
* set their state to suspended:
*/
PTHREAD_WAITQ_REMOVE(thread);
PTHREAD_SET_STATE(thread, PS_SUSPENDED);
break;
case PS_MUTEX_WAIT:
/* Mark the thread as suspended and still in a queue. */
thread->suspended = SUSP_MUTEX_WAIT;
PTHREAD_SET_STATE(thread, PS_SUSPENDED);
break;
case PS_COND_WAIT:
/* Mark the thread as suspended and still in a queue. */
thread->suspended = SUSP_COND_WAIT;
PTHREAD_SET_STATE(thread, PS_SUSPENDED);
break;
case PS_JOIN:
/* Mark the thread as suspended and joining: */
thread->suspended = SUSP_JOIN;
PTHREAD_NEW_STATE(thread, PS_SUSPENDED);
break;
case PS_FDLR_WAIT:
case PS_FDLW_WAIT:
case PS_FILE_WAIT:
/* Mark the thread as suspended: */
thread->suspended = SUSP_YES;
/*
* Threads in these states may be in queues.
* In order to preserve queue integrity, the
* cancelled thread must remove itself from the
* queue. Mark the thread as interrupted and
* set the state to running. When the thread
* resumes, it will remove itself from the queue
* and call the suspension completion routine.
*/
thread->interrupted = 1;
_thread_seterrno(thread, EINTR);
PTHREAD_NEW_STATE(thread, PS_RUNNING);
thread->continuation = finish_suspension;
break;
case PS_DEAD:
case PS_DEADLOCK:
case PS_STATE_MAX:
case PS_SUSPENDED:
/* Nothing needs to be done: */
break;
}
/*
* Undefer and handle pending signals, yielding if
* necessary:
*/
_thread_kern_sig_undefer();
}
return(ret);
}
static void
finish_suspension(void *arg)
{
struct pthread *curthread = _get_curthread();
if (curthread->suspended != SUSP_NO)
_thread_kern_sched_state(PS_SUSPENDED, __FILE__, __LINE__);
}
|
