thr_create.c revision 149691
1/* 2 * Copyright (c) 2003 Daniel M. Eischen <deischen@gdeb.com> 3 * Copyright (c) 1995-1998 John Birrell <jb@cimlogic.com.au> 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. All advertising materials mentioning features or use of this software 15 * must display the following acknowledgement: 16 * This product includes software developed by John Birrell. 17 * 4. Neither the name of the author nor the names of any co-contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * $FreeBSD: head/lib/libthr/thread/thr_create.c 149691 2005-09-01 15:21:23Z stefanf $ 34 */ 35 36#include <sys/types.h> 37#include <sys/signalvar.h> 38#include <errno.h> 39#include <stdlib.h> 40#include <string.h> 41#include <stddef.h> 42#include <pthread.h> 43 44#include "thr_private.h" 45 46static void free_thread(struct pthread *curthread, struct pthread *thread); 47static int create_stack(struct pthread_attr *pattr); 48static void free_stack(struct pthread *curthread, struct pthread_attr *pattr); 49static void thread_start(struct pthread *curthread); 50 51__weak_reference(_pthread_create, pthread_create); 52 53int 54_pthread_create(pthread_t * thread, const pthread_attr_t * attr, 55 void *(*start_routine) (void *), void *arg) 56{ 57 struct pthread *curthread, *new_thread; 58 struct thr_param param; 59 int ret = 0, locked; 60 61 _thr_check_init(); 62 63 /* 64 * Tell libc and others now they need lock to protect their data. 65 */ 66 if (_thr_isthreaded() == 0 && _thr_setthreaded(1)) 67 return (EAGAIN); 68 69 curthread = _get_curthread(); 70 if ((new_thread = _thr_alloc(curthread)) == NULL) 71 return (EAGAIN); 72 73 memset(¶m, 0, sizeof(param)); 74 75 if (attr == NULL || *attr == NULL) 76 /* Use the default thread attributes: */ 77 new_thread->attr = _pthread_attr_default; 78 else 79 new_thread->attr = *(*attr); 80 if (new_thread->attr.sched_inherit == PTHREAD_INHERIT_SCHED) { 81 /* inherit scheduling contention scope */ 82 if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM) 83 new_thread->attr.flags |= PTHREAD_SCOPE_SYSTEM; 84 else 85 new_thread->attr.flags &= ~PTHREAD_SCOPE_SYSTEM; 86 /* 87 * scheduling policy and scheduling parameters will be 88 * inherited in following code. 89 */ 90 } 91 92 if (_thr_scope_system > 0) 93 new_thread->attr.flags |= PTHREAD_SCOPE_SYSTEM; 94 else if (_thr_scope_system < 0) 95 new_thread->attr.flags &= ~PTHREAD_SCOPE_SYSTEM; 96 97 new_thread->tid = TID_TERMINATED; 98 99 if (create_stack(&new_thread->attr) != 0) { 100 /* Insufficient memory to create a stack: */ 101 _thr_free(curthread, new_thread); 102 return (EAGAIN); 103 } 104 /* 105 * Write a magic value to the thread structure 106 * to help identify valid ones: 107 */ 108 new_thread->magic = THR_MAGIC; 109 new_thread->start_routine = start_routine; 110 new_thread->arg = arg; 111 new_thread->cancelflags = PTHREAD_CANCEL_ENABLE | 112 PTHREAD_CANCEL_DEFERRED; 113 /* 114 * Check if this thread is to inherit the scheduling 115 * attributes from its parent: 116 */ 117 if (new_thread->attr.sched_inherit == PTHREAD_INHERIT_SCHED) { 118 /* 119 * Copy the scheduling attributes. Lock the scheduling 120 * lock to get consistent scheduling parameters. 121 */ 122 THR_LOCK(curthread); 123 new_thread->base_priority = curthread->base_priority; 124 new_thread->attr.prio = curthread->base_priority; 125 new_thread->attr.sched_policy = curthread->attr.sched_policy; 126 THR_UNLOCK(curthread); 127 } else { 128 /* 129 * Use just the thread priority, leaving the 130 * other scheduling attributes as their 131 * default values: 132 */ 133 new_thread->base_priority = new_thread->attr.prio; 134 } 135 new_thread->active_priority = new_thread->base_priority; 136 137 /* Initialize the mutex queue: */ 138 TAILQ_INIT(&new_thread->mutexq); 139 TAILQ_INIT(&new_thread->pri_mutexq); 140 141 /* Initialise hooks in the thread structure: */ 142 if (new_thread->attr.suspend == THR_CREATE_SUSPENDED) 143 new_thread->flags = THR_FLAGS_SUSPENDED; 144 new_thread->state = PS_RUNNING; 145 146 /* Add the new thread. */ 147 _thr_link(curthread, new_thread); 148 /* Return thread pointer eariler so that new thread can use it. */ 149 (*thread) = new_thread; 150 if (SHOULD_REPORT_EVENT(curthread, TD_CREATE)) { 151 THR_THREAD_LOCK(curthread, new_thread); 152 locked = 1; 153 } else 154 locked = 0; 155 param.start_func = (void (*)(void *)) thread_start; 156 param.arg = new_thread; 157 param.stack_base = new_thread->attr.stackaddr_attr; 158 param.stack_size = new_thread->attr.stacksize_attr; 159 param.tls_base = (char *)new_thread->tcb; 160 param.tls_size = sizeof(struct tcb); 161 param.child_tid = &new_thread->tid; 162 param.parent_tid = &new_thread->tid; 163 param.flags = 0; 164 if (new_thread->attr.flags & PTHREAD_SCOPE_SYSTEM) 165 param.flags |= THR_SYSTEM_SCOPE; 166 /* Schedule the new thread. */ 167 ret = thr_new(¶m, sizeof(param)); 168 if (ret != 0) { 169 if (locked) 170 THR_THREAD_UNLOCK(curthread, new_thread); 171 _thr_unlink(curthread, new_thread); 172 free_thread(curthread, new_thread); 173 (*thread) = 0; 174 ret = EAGAIN; 175 } else if (locked) { 176 _thr_report_creation(curthread, new_thread); 177 THR_THREAD_UNLOCK(curthread, new_thread); 178 } 179 return (ret); 180} 181 182static void 183free_thread(struct pthread *curthread, struct pthread *thread) 184{ 185 free_stack(curthread, &thread->attr); 186 curthread->tid = TID_TERMINATED; 187 _thr_free(curthread, thread); 188} 189 190static int 191create_stack(struct pthread_attr *pattr) 192{ 193 int ret; 194 195 /* Check if a stack was specified in the thread attributes: */ 196 if ((pattr->stackaddr_attr) != NULL) { 197 pattr->guardsize_attr = 0; 198 pattr->flags |= THR_STACK_USER; 199 ret = 0; 200 } 201 else 202 ret = _thr_stack_alloc(pattr); 203 return (ret); 204} 205 206static void 207free_stack(struct pthread *curthread, struct pthread_attr *pattr) 208{ 209 if ((pattr->flags & THR_STACK_USER) == 0) { 210 THREAD_LIST_LOCK(curthread); 211 /* Stack routines don't use malloc/free. */ 212 _thr_stack_free(pattr); 213 THREAD_LIST_UNLOCK(curthread); 214 } 215} 216 217static void 218thread_start(struct pthread *curthread) 219{ 220 if (curthread->flags & THR_FLAGS_NEED_SUSPEND) 221 _thr_suspend_check(curthread); 222 223 THR_LOCK(curthread); 224 THR_UNLOCK(curthread); 225 226 /* Run the current thread's start routine with argument: */ 227 pthread_exit(curthread->start_routine(curthread->arg)); 228 229 /* This point should never be reached. */ 230 PANIC("Thread has resumed after exit"); 231} 232