1 /* 2 * Copyright (c) 2005, David Xu <davidxu@freebsd.org> 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 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 17 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26 #include "namespace.h" 27 #include <machine/tls.h> 28 #include <errno.h> 29 #include <pthread.h> 30 #include "un-namespace.h" 31 32 #include "thr_private.h" 33 34 #define cpu_ccfence() __asm __volatile("" : : : "memory") 35 36 int _pthread_timedjoin_np(pthread_t pthread, void **thread_return, 37 const struct timespec *abstime); 38 39 static int join_common(pthread_t, void **, const struct timespec *); 40 41 static void backout_join(void *arg) 42 { 43 struct pthread *curthread = tls_get_curthread(); 44 struct pthread *pthread = (struct pthread *)arg; 45 46 THREAD_LIST_LOCK(curthread); 47 pthread->joiner = NULL; 48 THREAD_LIST_UNLOCK(curthread); 49 } 50 51 int 52 _pthread_join(pthread_t pthread, void **thread_return) 53 { 54 return (join_common(pthread, thread_return, NULL)); 55 } 56 57 int 58 _pthread_timedjoin_np(pthread_t pthread, void **thread_return, 59 const struct timespec *abstime) 60 { 61 if (abstime == NULL || abstime->tv_sec < 0 || abstime->tv_nsec < 0 || 62 abstime->tv_nsec >= 1000000000) 63 return (EINVAL); 64 65 return (join_common(pthread, thread_return, abstime)); 66 } 67 68 static int 69 join_common(pthread_t pthread, void **thread_return, 70 const struct timespec *abstime) 71 { 72 struct pthread *curthread = tls_get_curthread(); 73 struct timespec ts, ts2, *tsp; 74 void *tmp; 75 long state; 76 int oldcancel; 77 int ret = 0; 78 79 if (pthread == NULL) 80 return (EINVAL); 81 82 if (pthread == curthread) 83 return (EDEADLK); 84 85 THREAD_LIST_LOCK(curthread); 86 if ((ret = _thr_find_thread(curthread, pthread, 1)) != 0) { 87 ret = ESRCH; 88 } else if ((pthread->tlflags & TLFLAGS_DETACHED) != 0) { 89 ret = EINVAL; 90 } else if (pthread->joiner != NULL) { 91 /* Multiple joiners are not supported. */ 92 ret = ENOTSUP; 93 } 94 if (ret) { 95 THREAD_LIST_UNLOCK(curthread); 96 return (ret); 97 } 98 /* Set the running thread to be the joiner: */ 99 pthread->joiner = curthread; 100 101 THREAD_LIST_UNLOCK(curthread); 102 103 THR_CLEANUP_PUSH(curthread, backout_join, pthread); 104 oldcancel = _thr_cancel_enter(curthread); 105 106 while ((state = pthread->state) != PS_DEAD) { 107 cpu_ccfence(); 108 if (abstime != NULL) { 109 clock_gettime(CLOCK_REALTIME, &ts); 110 TIMESPEC_SUB(&ts2, abstime, &ts); 111 if (ts2.tv_sec < 0) { 112 ret = ETIMEDOUT; 113 break; 114 } 115 tsp = &ts2; 116 } else 117 tsp = NULL; 118 ret = _thr_umtx_wait(&pthread->state, state, tsp, 119 CLOCK_REALTIME); 120 if (ret == ETIMEDOUT) 121 break; 122 } 123 124 _thr_cancel_leave(curthread, oldcancel); 125 THR_CLEANUP_POP(curthread, 0); 126 127 if (ret == ETIMEDOUT) { 128 THREAD_LIST_LOCK(curthread); 129 pthread->joiner = NULL; 130 THREAD_LIST_UNLOCK(curthread); 131 } else { 132 ret = 0; 133 tmp = pthread->ret; 134 THREAD_LIST_LOCK(curthread); 135 pthread->tlflags |= TLFLAGS_DETACHED; 136 pthread->joiner = NULL; 137 THR_GCLIST_ADD(pthread); 138 THREAD_LIST_UNLOCK(curthread); 139 140 if (thread_return != NULL) 141 *thread_return = tmp; 142 } 143 return (ret); 144 } 145 146 __strong_reference(_pthread_join, pthread_join); 147 __strong_reference(_pthread_timedjoin_np, pthread_timedjoin_np); 148