1 /* 2 * Copyright (c) 2005 David Xu <davidxu@freebsd.org> 3 * Copyright (c) 2003 Daniel M. Eischen <deischen@gdeb.com> 4 * Copyright (c) 1995-1998 John Birrell <jb@cimlogic.com.au> 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by John Birrell. 18 * 4. Neither the name of the author nor the names of any co-contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * $FreeBSD: src/lib/libpthread/thread/thr_create.c,v 1.58 2004/10/23 23:28:36 davidxu Exp $ 35 * $DragonFly: src/lib/libthread_xu/thread/thr_create.c,v 1.10 2006/04/06 13:03:09 davidxu Exp $ 36 */ 37 38 #include "namespace.h" 39 #include <errno.h> 40 #include <stdlib.h> 41 #include <string.h> 42 #include <fcntl.h> 43 #include <unistd.h> 44 #include <stddef.h> 45 #include <sys/time.h> 46 #include <machine/reg.h> 47 #include <machine/tls.h> 48 49 #include <pthread.h> 50 #include <sys/signalvar.h> 51 #include "un-namespace.h" 52 53 #include "thr_private.h" 54 #include "libc_private.h" 55 56 struct start_arg { 57 struct pthread *thread; 58 volatile umtx_t started; 59 }; 60 61 static int create_stack(struct pthread_attr *pattr); 62 static void thread_start(void *); 63 64 int 65 _pthread_create(pthread_t * thread, const pthread_attr_t * attr, 66 void *(*start_routine) (void *), void *arg) 67 { 68 struct start_arg start_arg; 69 void *stack; 70 sigset_t sigmask, oldsigmask; 71 struct pthread *curthread, *new_thread; 72 int ret = 0, locked; 73 74 _thr_check_init(); 75 76 /* 77 * Tell libc and others now they need lock to protect their data. 78 */ 79 if (_thr_isthreaded() == 0 && _thr_setthreaded(1)) 80 return (EAGAIN); 81 82 curthread = tls_get_curthread(); 83 if ((new_thread = _thr_alloc(curthread)) == NULL) 84 return (EAGAIN); 85 86 if (attr == NULL || *attr == NULL) 87 /* Use the default thread attributes: */ 88 new_thread->attr = _pthread_attr_default; 89 else 90 new_thread->attr = *(*attr); 91 if (new_thread->attr.sched_inherit == PTHREAD_INHERIT_SCHED) { 92 /* inherit scheduling contention scope */ 93 if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM) 94 new_thread->attr.flags |= PTHREAD_SCOPE_SYSTEM; 95 else 96 new_thread->attr.flags &= ~PTHREAD_SCOPE_SYSTEM; 97 /* 98 * scheduling policy and scheduling parameters will be 99 * inherited in following code. 100 */ 101 } 102 103 if (_thread_scope_system > 0) 104 new_thread->attr.flags |= PTHREAD_SCOPE_SYSTEM; 105 else if (_thread_scope_system < 0) 106 new_thread->attr.flags &= ~PTHREAD_SCOPE_SYSTEM; 107 108 if (create_stack(&new_thread->attr) != 0) { 109 /* Insufficient memory to create a stack: */ 110 new_thread->terminated = 1; 111 _thr_free(curthread, new_thread); 112 return (EAGAIN); 113 } 114 /* 115 * Write a magic value to the thread structure 116 * to help identify valid ones: 117 */ 118 new_thread->magic = THR_MAGIC; 119 new_thread->start_routine = start_routine; 120 new_thread->arg = arg; 121 new_thread->cancelflags = PTHREAD_CANCEL_ENABLE | 122 PTHREAD_CANCEL_DEFERRED; 123 /* 124 * Check if this thread is to inherit the scheduling 125 * attributes from its parent: 126 */ 127 if (new_thread->attr.sched_inherit == PTHREAD_INHERIT_SCHED) { 128 /* 129 * Copy the scheduling attributes. Lock the scheduling 130 * lock to get consistent scheduling parameters. 131 */ 132 THR_LOCK(curthread); 133 new_thread->base_priority = curthread->base_priority; 134 new_thread->attr.prio = curthread->base_priority; 135 new_thread->attr.sched_policy = curthread->attr.sched_policy; 136 THR_UNLOCK(curthread); 137 } else { 138 /* 139 * Use just the thread priority, leaving the 140 * other scheduling attributes as their 141 * default values: 142 */ 143 new_thread->base_priority = new_thread->attr.prio; 144 } 145 new_thread->active_priority = new_thread->base_priority; 146 147 /* Initialize the mutex queue: */ 148 TAILQ_INIT(&new_thread->mutexq); 149 150 /* Initialise hooks in the thread structure: */ 151 if (new_thread->attr.suspend == THR_CREATE_SUSPENDED) 152 new_thread->flags = THR_FLAGS_NEED_SUSPEND; 153 154 new_thread->state = PS_RUNNING; 155 156 if (new_thread->attr.flags & PTHREAD_CREATE_DETACHED) 157 new_thread->tlflags |= TLFLAGS_DETACHED; 158 159 /* 160 * Thread created by thr_create() inherits currrent thread 161 * sigmask, however, before new thread setup itself correctly, 162 * it can not handle signal, so we should masks all signals here. 163 */ 164 SIGFILLSET(sigmask); 165 __sys_sigprocmask(SIG_SETMASK, &sigmask, &oldsigmask); 166 new_thread->sigmask = oldsigmask; 167 /* Add the new thread. */ 168 new_thread->refcount = 1; 169 _thr_link(curthread, new_thread); 170 /* Return thread pointer eariler so that new thread can use it. */ 171 (*thread) = new_thread; 172 if (SHOULD_REPORT_EVENT(curthread, TD_CREATE)) { 173 THR_THREAD_LOCK(curthread, new_thread); 174 locked = 1; 175 } else 176 locked = 0; 177 /* Schedule the new thread. */ 178 stack = (char *)new_thread->attr.stackaddr_attr + 179 new_thread->attr.stacksize_attr; 180 start_arg.thread = new_thread; 181 start_arg.started = 0; 182 ret = rfork_thread(RFPROC | RFNOWAIT | RFMEM | RFSIGSHARE, stack, 183 (int (*)(void *))thread_start, &start_arg); 184 __sys_sigprocmask(SIG_SETMASK, &oldsigmask, NULL); 185 if (ret >= 0) { 186 /* 187 * Wait until new thread get its thread id, so we can 188 * send signal to it immediately after we return. 189 */ 190 while (start_arg.started == 0) 191 _thr_umtx_wait(&start_arg.started, 0, NULL, 0); 192 ret = 0; 193 } else { 194 ret = EAGAIN; 195 } 196 if (ret != 0) { 197 if (!locked) 198 THR_THREAD_LOCK(curthread, new_thread); 199 new_thread->state = PS_DEAD; 200 new_thread->terminated = 1; 201 if (new_thread->flags & THR_FLAGS_NEED_SUSPEND) { 202 new_thread->cycle++; 203 _thr_umtx_wake(&new_thread->cycle, INT_MAX); 204 } 205 THR_THREAD_UNLOCK(curthread, new_thread); 206 THREAD_LIST_LOCK(curthread); 207 _thread_active_threads--; 208 new_thread->tlflags |= TLFLAGS_DETACHED; 209 _thr_ref_delete_unlocked(curthread, new_thread); 210 THREAD_LIST_UNLOCK(curthread); 211 (*thread) = 0; 212 ret = EAGAIN; 213 } else if (locked) { 214 _thr_report_creation(curthread, new_thread); 215 THR_THREAD_UNLOCK(curthread, new_thread); 216 } 217 return (ret); 218 } 219 220 static int 221 create_stack(struct pthread_attr *pattr) 222 { 223 int ret; 224 225 /* Check if a stack was specified in the thread attributes: */ 226 if ((pattr->stackaddr_attr) != NULL) { 227 pattr->guardsize_attr = 0; 228 pattr->flags |= THR_STACK_USER; 229 ret = 0; 230 } 231 else 232 ret = _thr_stack_alloc(pattr); 233 return (ret); 234 } 235 236 static void 237 thread_start(void *arg) 238 { 239 struct pthread *curthread; 240 struct start_arg *start_arg = arg; 241 242 curthread = start_arg->thread; 243 curthread->tid = _thr_get_tid(); 244 tls_set_tcb(curthread->tcb); 245 start_arg->started = 1; 246 _thr_umtx_wake(&start_arg->started, 1); 247 248 /* Thread was created with all signals blocked, unblock them. */ 249 __sys_sigprocmask(SIG_SETMASK, &curthread->sigmask, NULL); 250 251 THR_LOCK(curthread); 252 THR_UNLOCK(curthread); 253 254 if (curthread->flags & THR_FLAGS_NEED_SUSPEND) 255 _thr_suspend_check(curthread); 256 257 /* Run the current thread's start routine with argument: */ 258 _pthread_exit(curthread->start_routine(curthread->arg)); 259 260 /* This point should never be reached. */ 261 PANIC("Thread has resumed after exit"); 262 } 263 264 __strong_reference(_pthread_create, pthread_create); 265