thr_resume_np.c revision 299521 
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: stable/10/lib/libthr/thread/thr_resume_np.c 299521 2016-05-12 06:53:22Z kib $
30 */
31
32#include "namespace.h"
33#include <errno.h>
34#include <pthread.h>
35#include <pthread_np.h>
36#include "un-namespace.h"
37
38#include "thr_private.h"
39
40__weak_reference(_pthread_resume_np, pthread_resume_np);
41__weak_reference(_pthread_resume_all_np, pthread_resume_all_np);
42
43static void resume_common(struct pthread *thread);
44
45/* Resume a thread: */
46int
47_pthread_resume_np(pthread_t thread)
48{
49	struct pthread *curthread = _get_curthread();
50	int ret;
51
52	/* Add a reference to the thread: */
53	if ((ret = _thr_find_thread(curthread, thread, /*include dead*/0)) == 0) {
54		/* Lock the threads scheduling queue: */
55		resume_common(thread);
56		THR_THREAD_UNLOCK(curthread, thread);
57	}
58	return (ret);
59}
60
61void
62_pthread_resume_all_np(void)
63{
64	struct pthread *curthread = _get_curthread();
65	struct pthread *thread;
66	int old_nocancel;
67
68	old_nocancel = curthread->no_cancel;
69	curthread->no_cancel = 1;
70	_thr_suspend_all_lock(curthread);
71	/* Take the thread list lock: */
72	THREAD_LIST_RDLOCK(curthread);
73
74	TAILQ_FOREACH(thread, &_thread_list, tle) {
75		if (thread != curthread) {
76			THR_THREAD_LOCK(curthread, thread);
77			resume_common(thread);
78			THR_THREAD_UNLOCK(curthread, thread);
79		}
80	}
81
82	/* Release the thread list lock: */
83	THREAD_LIST_UNLOCK(curthread);
84	_thr_suspend_all_unlock(curthread);
85	curthread->no_cancel = old_nocancel;
86	_thr_testcancel(curthread);
87}
88
89static void
90resume_common(struct pthread *thread)
91{
92	/* Clear the suspend flag: */
93	thread->flags &= ~(THR_FLAGS_NEED_SUSPEND | THR_FLAGS_SUSPENDED);
94	thread->cycle++;
95	_thr_umtx_wake(&thread->cycle, 1, 0);
96}
97