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 1.5 2005/10/10 13:45:57 davidxu Exp $ 36 */ 37 #include <errno.h> 38 #include <stdlib.h> 39 #include <string.h> 40 #include <fcntl.h> 41 #include <unistd.h> 42 #include <stddef.h> 43 #include <sys/time.h> 44 #include <machine/reg.h> 45 #include <machine/tls.h> 46 47 #include <pthread.h> 48 #include <sys/signalvar.h> 49 50 #include "thr_private.h" 51 #include "libc_private.h" 52 53 struct start_arg { 54 struct pthread *thread; 55 volatile umtx_t started; 56 }; 57 58 static void free_thread(struct pthread *curthread, struct pthread *thread); 59 static int create_stack(struct pthread_attr *pattr); 60 static void free_stack(struct pthread *curthread, struct pthread_attr *pattr); 61 static void thread_start(void *); 62 63 __weak_reference(_pthread_create, pthread_create); 64 65 int 66 _pthread_create(pthread_t * thread, const pthread_attr_t * attr, 67 void *(*start_routine) (void *), void *arg) 68 { 69 struct start_arg start_arg; 70 void *stack; 71 sigset_t sigmask, oldsigmask; 72 struct pthread *curthread, *new_thread; 73 int ret = 0, locked; 74 75 _thr_check_init(); 76 77 /* 78 * Tell libc and others now they need lock to protect their data. 79 */ 80 if (_thr_isthreaded() == 0 && _thr_setthreaded(1)) 81 return (EAGAIN); 82 83 curthread = tls_get_curthread(); 84 if ((new_thread = _thr_alloc(curthread)) == NULL) 85 return (EAGAIN); 86 87 if (attr == NULL || *attr == NULL) 88 /* Use the default thread attributes: */ 89 new_thread->attr = _pthread_attr_default; 90 else 91 new_thread->attr = *(*attr); 92 if (new_thread->attr.sched_inherit == PTHREAD_INHERIT_SCHED) { 93 /* inherit scheduling contention scope */ 94 if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM) 95 new_thread->attr.flags |= PTHREAD_SCOPE_SYSTEM; 96 else 97 new_thread->attr.flags &= ~PTHREAD_SCOPE_SYSTEM; 98 /* 99 * scheduling policy and scheduling parameters will be 100 * inherited in following code. 101 */ 102 } 103 104 if (_thread_scope_system > 0) 105 new_thread->attr.flags |= PTHREAD_SCOPE_SYSTEM; 106 else if (_thread_scope_system < 0) 107 new_thread->attr.flags &= ~PTHREAD_SCOPE_SYSTEM; 108 109 if (create_stack(&new_thread->attr) != 0) { 110 /* Insufficient memory to create a stack: */ 111 new_thread->terminated = 1; 112 _thr_free(curthread, new_thread); 113 return (EAGAIN); 114 } 115 /* 116 * Write a magic value to the thread structure 117 * to help identify valid ones: 118 */ 119 new_thread->magic = THR_MAGIC; 120 new_thread->start_routine = start_routine; 121 new_thread->arg = arg; 122 new_thread->cancelflags = PTHREAD_CANCEL_ENABLE | 123 PTHREAD_CANCEL_DEFERRED; 124 /* 125 * Check if this thread is to inherit the scheduling 126 * attributes from its parent: 127 */ 128 if (new_thread->attr.sched_inherit == PTHREAD_INHERIT_SCHED) { 129 /* 130 * Copy the scheduling attributes. Lock the scheduling 131 * lock to get consistent scheduling parameters. 132 */ 133 THR_LOCK(curthread); 134 new_thread->base_priority = curthread->base_priority; 135 new_thread->attr.prio = curthread->base_priority; 136 new_thread->attr.sched_policy = curthread->attr.sched_policy; 137 THR_UNLOCK(curthread); 138 } else { 139 /* 140 * Use just the thread priority, leaving the 141 * other scheduling attributes as their 142 * default values: 143 */ 144 new_thread->base_priority = new_thread->attr.prio; 145 } 146 new_thread->active_priority = new_thread->base_priority; 147 148 /* Initialize the mutex queue: */ 149 TAILQ_INIT(&new_thread->mutexq); 150 TAILQ_INIT(&new_thread->pri_mutexq); 151 152 /* Initialise hooks in the thread structure: */ 153 if (new_thread->attr.suspend == THR_CREATE_SUSPENDED) 154 new_thread->flags = THR_FLAGS_NEED_SUSPEND; 155 new_thread->state = PS_RUNNING; 156 /* 157 * Thread created by thr_create() inherits currrent thread 158 * sigmask, however, before new thread setup itself correctly, 159 * it can not handle signal, so we should masks all signals here. 160 */ 161 SIGFILLSET(sigmask); 162 __sys_sigprocmask(SIG_SETMASK, &sigmask, &oldsigmask); 163 new_thread->sigmask = oldsigmask; 164 /* Add the new thread. */ 165 _thr_link(curthread, new_thread); 166 /* Return thread pointer eariler so that new thread can use it. */ 167 (*thread) = new_thread; 168 if (SHOULD_REPORT_EVENT(curthread, TD_CREATE)) { 169 THR_THREAD_LOCK(curthread, new_thread); 170 locked = 1; 171 } else 172 locked = 0; 173 /* Schedule the new thread. */ 174 stack = (char *)new_thread->attr.stackaddr_attr + 175 new_thread->attr.stacksize_attr; 176 start_arg.thread = new_thread; 177 start_arg.started = 0; 178 ret = rfork_thread(RFPROC | RFNOWAIT | RFMEM | RFSIGSHARE, stack, 179 (int (*)(void *))thread_start, &start_arg); 180 __sys_sigprocmask(SIG_SETMASK, &oldsigmask, NULL); 181 if (ret >= 0) { 182 /* 183 * Wait until new thread get its thread id, so we can 184 * send signal to it immediately after we return. 185 */ 186 while (start_arg.started == 0) 187 _thr_umtx_wait(&start_arg.started, 0, NULL, 0); 188 ret = 0; 189 } else { 190 ret = EAGAIN; 191 } 192 if (ret != 0) { 193 if (locked) 194 THR_THREAD_UNLOCK(curthread, new_thread); 195 _thr_unlink(curthread, new_thread); 196 free_thread(curthread, new_thread); 197 (*thread) = 0; 198 ret = EAGAIN; 199 } else if (locked) { 200 _thr_report_creation(curthread, new_thread); 201 THR_THREAD_UNLOCK(curthread, new_thread); 202 } 203 return (ret); 204 } 205 206 static void 207 free_thread(struct pthread *curthread, struct pthread *thread) 208 { 209 free_stack(curthread, &thread->attr); 210 curthread->terminated = 1; 211 _thr_free(curthread, thread); 212 } 213 214 static int 215 create_stack(struct pthread_attr *pattr) 216 { 217 int ret; 218 219 /* Check if a stack was specified in the thread attributes: */ 220 if ((pattr->stackaddr_attr) != NULL) { 221 pattr->guardsize_attr = 0; 222 pattr->flags |= THR_STACK_USER; 223 ret = 0; 224 } 225 else 226 ret = _thr_stack_alloc(pattr); 227 return (ret); 228 } 229 230 static void 231 free_stack(struct pthread *curthread, struct pthread_attr *pattr) 232 { 233 if ((pattr->flags & THR_STACK_USER) == 0) { 234 THREAD_LIST_LOCK(curthread); 235 /* Stack routines don't use malloc/free. */ 236 _thr_stack_free(pattr); 237 THREAD_LIST_UNLOCK(curthread); 238 } 239 } 240 241 static void 242 thread_start(void *arg) 243 { 244 struct pthread *curthread; 245 struct start_arg *start_arg = arg; 246 247 curthread = start_arg->thread; 248 curthread->tid = _thr_get_tid(); 249 tls_set_tcb(curthread->tcb); 250 start_arg->started = 1; 251 _thr_umtx_wake(&start_arg->started, 1); 252 253 THR_LOCK(curthread); 254 THR_UNLOCK(curthread); 255 256 /* Thread was created with all signals blocked, unblock them. */ 257 __sys_sigprocmask(SIG_SETMASK, &curthread->sigmask, NULL); 258 259 if (curthread->flags & THR_FLAGS_NEED_SUSPEND) 260 _thr_suspend_check(curthread); 261 262 /* Run the current thread's start routine with argument: */ 263 pthread_exit(curthread->start_routine(curthread->arg)); 264 265 /* This point should never be reached. */ 266 PANIC("Thread has resumed after exit"); 267 } 268