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: releng/10.2/lib/libkse/thread/thr_resume_np.c 174689 2007-12-16 23:29:57Z deischen $
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
38int	_pthread_resume_np(pthread_t thread);
39void	_pthread_resume_all_np(void);
40
41static 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: */
48int
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
68void
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
95static struct kse_mailbox *
96resume_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