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. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by John Birrell.
16  * 4. Neither the name of the author nor the names of any co-contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  *
32  * $FreeBSD: src/lib/libpthread/thread/thr_resume_np.c,v 1.18 2003/07/23 02:11:07 deischen Exp $
33  * $DragonFly: src/lib/libthread_xu/thread/thr_resume_np.c,v 1.2 2005/03/29 19:26:20 joerg Exp $
34  */
35 
36 #include <machine/tls.h>
37 
38 #include <errno.h>
39 #include <pthread.h>
40 #include "thr_private.h"
41 
42 __weak_reference(_pthread_resume_np, pthread_resume_np);
43 __weak_reference(_pthread_resume_all_np, pthread_resume_all_np);
44 
45 static void resume_common(struct pthread *thread);
46 
47 /* Resume a thread: */
48 int
49 _pthread_resume_np(pthread_t thread)
50 {
51 	struct pthread *curthread = tls_get_curthread();
52 	int ret;
53 
54 	/* Add a reference to the thread: */
55 	if ((ret = _thr_ref_add(curthread, thread, /*include dead*/0)) == 0) {
56 		/* Lock the threads scheduling queue: */
57 		THR_THREAD_LOCK(curthread, thread);
58 		resume_common(thread);
59 		THR_THREAD_UNLOCK(curthread, thread);
60 		_thr_ref_delete(curthread, thread);
61 	}
62 	return (ret);
63 }
64 
65 void
66 _pthread_resume_all_np(void)
67 {
68 	struct pthread *curthread = tls_get_curthread();
69 	struct pthread *thread;
70 
71 	/* Take the thread list lock: */
72 	THREAD_LIST_LOCK(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 }
85 
86 static void
87 resume_common(struct pthread *thread)
88 {
89 	/* Clear the suspend flag: */
90 	thread->flags &= ~THR_FLAGS_NEED_SUSPEND;
91 	thread->cycle++;
92 	_thr_umtx_wake(&thread->cycle, 1);
93 	_thr_send_sig(thread, SIGCANCEL);
94 }
95