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 */ 36 37 #include "namespace.h" 38 #include <errno.h> 39 #include <stdlib.h> 40 #include <string.h> 41 #include <fcntl.h> 42 #include <unistd.h> 43 #include <stddef.h> 44 #include <sys/time.h> 45 #include <machine/reg.h> 46 #include <machine/tls.h> 47 48 #include <pthread.h> 49 #include <sys/signalvar.h> 50 #include "un-namespace.h" 51 52 #include "thr_private.h" 53 #include "libc_private.h" 54 55 static int create_stack(struct pthread_attr *pattr); 56 static void thread_start(void *); 57 58 int 59 _pthread_create(pthread_t * thread, const pthread_attr_t * attr, 60 void *(*start_routine) (void *), void *arg) 61 { 62 struct lwp_params create_params; 63 void *stack; 64 sigset_t sigmask, oldsigmask; 65 struct pthread *curthread, *new_thread; 66 int ret = 0, locked; 67 68 _thr_check_init(); 69 70 /* 71 * Tell libc and others now they need lock to protect their data. 72 */ 73 if (_thr_isthreaded() == 0 && _thr_setthreaded(1)) 74 return (EAGAIN); 75 76 curthread = tls_get_curthread(); 77 if ((new_thread = _thr_alloc(curthread)) == NULL) 78 return (EAGAIN); 79 80 if (attr == NULL || *attr == NULL) 81 /* Use the default thread attributes: */ 82 new_thread->attr = _pthread_attr_default; 83 else 84 new_thread->attr = *(*attr); 85 if (new_thread->attr.sched_inherit == PTHREAD_INHERIT_SCHED) { 86 /* inherit scheduling contention scope */ 87 if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM) 88 new_thread->attr.flags |= PTHREAD_SCOPE_SYSTEM; 89 else 90 new_thread->attr.flags &= ~PTHREAD_SCOPE_SYSTEM; 91 /* 92 * scheduling policy and scheduling parameters will be 93 * inherited in following code. 94 */ 95 } 96 97 if (_thread_scope_system > 0) 98 new_thread->attr.flags |= PTHREAD_SCOPE_SYSTEM; 99 else if (_thread_scope_system < 0) 100 new_thread->attr.flags &= ~PTHREAD_SCOPE_SYSTEM; 101 102 if (create_stack(&new_thread->attr) != 0) { 103 /* Insufficient memory to create a stack: */ 104 new_thread->terminated = 1; 105 _thr_free(curthread, new_thread); 106 return (EAGAIN); 107 } 108 /* 109 * Write a magic value to the thread structure 110 * to help identify valid ones: 111 */ 112 new_thread->magic = THR_MAGIC; 113 new_thread->start_routine = start_routine; 114 new_thread->arg = arg; 115 new_thread->cancelflags = PTHREAD_CANCEL_ENABLE | 116 PTHREAD_CANCEL_DEFERRED; 117 /* 118 * Check if this thread is to inherit the scheduling 119 * attributes from its parent: 120 */ 121 if (new_thread->attr.sched_inherit == PTHREAD_INHERIT_SCHED) { 122 /* 123 * Copy the scheduling attributes. Lock the scheduling 124 * lock to get consistent scheduling parameters. 125 */ 126 THR_LOCK(curthread); 127 new_thread->base_priority = curthread->base_priority; 128 new_thread->attr.prio = curthread->attr.prio; 129 new_thread->attr.sched_policy = curthread->attr.sched_policy; 130 THR_UNLOCK(curthread); 131 } else { 132 /* 133 * Use just the thread priority, leaving the 134 * other scheduling attributes as their 135 * default values: 136 */ 137 new_thread->base_priority = new_thread->attr.prio; 138 } 139 new_thread->active_priority = new_thread->base_priority; 140 141 /* Initialize the mutex queue: */ 142 TAILQ_INIT(&new_thread->mutexq); 143 144 /* Initialise hooks in the thread structure: */ 145 if (new_thread->attr.suspend == THR_CREATE_SUSPENDED) 146 new_thread->flags = THR_FLAGS_NEED_SUSPEND; 147 148 new_thread->state = PS_RUNNING; 149 150 if (new_thread->attr.flags & PTHREAD_CREATE_DETACHED) 151 new_thread->tlflags |= TLFLAGS_DETACHED; 152 153 /* Add the new thread. */ 154 new_thread->refcount = 1; 155 _thr_link(curthread, new_thread); 156 /* Return thread pointer eariler so that new thread can use it. */ 157 (*thread) = new_thread; 158 if (SHOULD_REPORT_EVENT(curthread, TD_CREATE)) { 159 THR_THREAD_LOCK(curthread, new_thread); 160 locked = 1; 161 } else 162 locked = 0; 163 /* Schedule the new thread. */ 164 stack = (char *)new_thread->attr.stackaddr_attr + 165 new_thread->attr.stacksize_attr; 166 bzero(&create_params, sizeof(create_params)); 167 create_params.lwp_func = thread_start; 168 create_params.lwp_arg = new_thread; 169 create_params.lwp_stack = stack; 170 create_params.lwp_tid1 = &new_thread->tid; 171 /* 172 * Thread created by thr_create() inherits currrent thread 173 * sigmask, however, before new thread setup itself correctly, 174 * it can not handle signal, so we should mask all signals here. 175 * We do this at the very last moment, so that we don't run 176 * into problems while we have all signals disabled. 177 */ 178 SIGFILLSET(sigmask); 179 __sys_sigprocmask(SIG_SETMASK, &sigmask, &oldsigmask); 180 new_thread->sigmask = oldsigmask; 181 ret = lwp_create(&create_params); 182 __sys_sigprocmask(SIG_SETMASK, &oldsigmask, NULL); 183 if (ret != 0) { 184 if (!locked) 185 THR_THREAD_LOCK(curthread, new_thread); 186 new_thread->state = PS_DEAD; 187 new_thread->terminated = 1; 188 if (new_thread->flags & THR_FLAGS_NEED_SUSPEND) { 189 new_thread->cycle++; 190 _thr_umtx_wake(&new_thread->cycle, INT_MAX); 191 } 192 THR_THREAD_UNLOCK(curthread, new_thread); 193 THREAD_LIST_LOCK(curthread); 194 _thread_active_threads--; 195 new_thread->tlflags |= TLFLAGS_DETACHED; 196 _thr_ref_delete_unlocked(curthread, new_thread); 197 THREAD_LIST_UNLOCK(curthread); 198 (*thread) = NULL; 199 ret = EAGAIN; 200 } else if (locked) { 201 _thr_report_creation(curthread, new_thread); 202 THR_THREAD_UNLOCK(curthread, new_thread); 203 } 204 return (ret); 205 } 206 207 static int 208 create_stack(struct pthread_attr *pattr) 209 { 210 int ret; 211 212 /* Check if a stack was specified in the thread attributes: */ 213 if ((pattr->stackaddr_attr) != NULL) { 214 pattr->guardsize_attr = 0; 215 pattr->flags |= THR_STACK_USER; 216 ret = 0; 217 } 218 else 219 ret = _thr_stack_alloc(pattr); 220 return (ret); 221 } 222 223 static void 224 thread_start(void *arg) 225 { 226 struct pthread *curthread = (struct pthread *)arg; 227 228 tls_set_tcb(curthread->tcb); 229 230 /* Thread was created with all signals blocked, unblock them. */ 231 __sys_sigprocmask(SIG_SETMASK, &curthread->sigmask, NULL); 232 233 THR_LOCK(curthread); 234 THR_UNLOCK(curthread); 235 236 if (curthread->flags & THR_FLAGS_NEED_SUSPEND) 237 _thr_suspend_check(curthread); 238 _nmalloc_thr_init(); 239 240 /* Run the current thread's start routine with argument: */ 241 _pthread_exit(curthread->start_routine(curthread->arg)); 242 243 /* This point should never be reached. */ 244 PANIC("Thread has resumed after exit"); 245 } 246 247 __strong_reference(_pthread_create, pthread_create); 248