1 /*
2 * Copyright (c) 1995 John Birrell <jb@cimlogic.com.au>.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of the author nor the names of any co-contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * $FreeBSD$
30 */
31
32 #include "namespace.h"
33 #include <errno.h>
34 #include <pthread.h>
35 #include "un-namespace.h"
36 #include "thr_private.h"
37
38 int _pthread_resume_np(pthread_t thread);
39 void _pthread_resume_all_np(void);
40
41 static struct kse_mailbox *resume_common(struct pthread *);
42
43 __weak_reference(_pthread_resume_np, pthread_resume_np);
44 __weak_reference(_pthread_resume_all_np, pthread_resume_all_np);
45
46
47 /* Resume a thread: */
48 int
_pthread_resume_np(pthread_t thread)49 _pthread_resume_np(pthread_t thread)
50 {
51 struct pthread *curthread = _get_curthread();
52 struct kse_mailbox *kmbx;
53 int ret;
54
55 /* Add a reference to the thread: */
56 if ((ret = _thr_ref_add(curthread, thread, /*include dead*/0)) == 0) {
57 /* Lock the threads scheduling queue: */
58 THR_SCHED_LOCK(curthread, thread);
59 kmbx = resume_common(thread);
60 THR_SCHED_UNLOCK(curthread, thread);
61 _thr_ref_delete(curthread, thread);
62 if (kmbx != NULL)
63 kse_wakeup(kmbx);
64 }
65 return (ret);
66 }
67
68 void
_pthread_resume_all_np(void)69 _pthread_resume_all_np(void)
70 {
71 struct pthread *curthread = _get_curthread();
72 struct pthread *thread;
73 struct kse_mailbox *kmbx;
74 kse_critical_t crit;
75
76 /* Take the thread list lock: */
77 crit = _kse_critical_enter();
78 KSE_LOCK_ACQUIRE(curthread->kse, &_thread_list_lock);
79
80 TAILQ_FOREACH(thread, &_thread_list, tle) {
81 if (thread != curthread) {
82 THR_SCHED_LOCK(curthread, thread);
83 kmbx = resume_common(thread);
84 THR_SCHED_UNLOCK(curthread, thread);
85 if (kmbx != NULL)
86 kse_wakeup(kmbx);
87 }
88 }
89
90 /* Release the thread list lock: */
91 KSE_LOCK_RELEASE(curthread->kse, &_thread_list_lock);
92 _kse_critical_leave(crit);
93 }
94
95 static struct kse_mailbox *
resume_common(struct pthread * thread)96 resume_common(struct pthread *thread)
97 {
98 /* Clear the suspend flag: */
99 thread->flags &= ~THR_FLAGS_SUSPENDED;
100
101 /*
102 * If the thread's state is suspended, that means it is
103 * now runnable but not in any scheduling queue. Set the
104 * state to running and insert it into the run queue.
105 */
106 if (thread->state == PS_SUSPENDED)
107 return (_thr_setrunnable_unlocked(thread));
108 else
109 return (NULL);
110 }
111