1 /* 2 * Copyright (c) 1995-1998 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_suspend_np.c,v 1.19 2003/05/04 16:17:01 deischen Exp $ 33 * $DragonFly: src/lib/libthread_xu/thread/thr_suspend_np.c,v 1.2 2005/03/29 19:26:20 joerg Exp $ 34 */ 35 36 #include <machine/tls.h> 37 #include <errno.h> 38 #include <pthread.h> 39 #include "thr_private.h" 40 41 static void suspend_common(struct pthread *thread); 42 43 __weak_reference(_pthread_suspend_np, pthread_suspend_np); 44 __weak_reference(_pthread_suspend_all_np, pthread_suspend_all_np); 45 46 /* Suspend a thread: */ 47 int 48 _pthread_suspend_np(pthread_t thread) 49 { 50 struct pthread *curthread = tls_get_curthread(); 51 int ret; 52 53 /* Suspending the current thread doesn't make sense. */ 54 if (thread == curthread) 55 ret = EDEADLK; 56 57 /* Add a reference to the thread: */ 58 else if ((ret = _thr_ref_add(curthread, thread, /*include dead*/0)) 59 == 0) { 60 /* Lock the threads scheduling queue: */ 61 THR_THREAD_LOCK(curthread, thread); 62 suspend_common(thread); 63 /* Unlock the threads scheduling queue: */ 64 THR_THREAD_UNLOCK(curthread, thread); 65 66 /* Don't forget to remove the reference: */ 67 _thr_ref_delete(curthread, thread); 68 } 69 return (ret); 70 } 71 72 void 73 _pthread_suspend_all_np(void) 74 { 75 struct pthread *curthread = tls_get_curthread(); 76 struct pthread *thread; 77 78 /* Take the thread list lock: */ 79 THREAD_LIST_LOCK(curthread); 80 81 TAILQ_FOREACH(thread, &_thread_list, tle) { 82 if (thread != curthread) { 83 THR_THREAD_LOCK(curthread, thread); 84 suspend_common(thread); 85 THR_THREAD_UNLOCK(curthread, thread); 86 } 87 } 88 89 /* Release the thread list lock: */ 90 THREAD_LIST_UNLOCK(curthread); 91 } 92 93 static void 94 suspend_common(struct pthread *thread) 95 { 96 if (thread->state != PS_DEAD) { 97 thread->flags |= THR_FLAGS_NEED_SUSPEND; 98 _thr_send_sig(thread, SIGCANCEL); 99 } 100 } 101