1 /* 2 * Copyright (c) 2003 Daniel M. Eischen <deischen@gdeb.com> 3 * Copyright (c) 2005, David Xu <davidxu@freebsd.org> 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 unmodified, this list of conditions, and the following 11 * 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 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 * 27 * $FreeBSD$ 28 */ 29 30 #include "namespace.h" 31 #include <sys/types.h> 32 #include <sys/signalvar.h> 33 #include <errno.h> 34 #include <stdlib.h> 35 #include <string.h> 36 #include <stddef.h> 37 #include <pthread.h> 38 #include "un-namespace.h" 39 40 #include "thr_private.h" 41 42 static int create_stack(struct pthread_attr *pattr); 43 static void thread_start(struct pthread *curthread); 44 45 __weak_reference(_pthread_create, pthread_create); 46 47 int 48 _pthread_create(pthread_t * thread, const pthread_attr_t * attr, 49 void *(*start_routine) (void *), void *arg) 50 { 51 struct pthread *curthread, *new_thread; 52 struct thr_param param; 53 int ret = 0, locked, create_suspended; 54 sigset_t set, oset; 55 56 _thr_check_init(); 57 58 /* 59 * Tell libc and others now they need lock to protect their data. 60 */ 61 if (_thr_isthreaded() == 0 && _thr_setthreaded(1)) 62 return (EAGAIN); 63 64 curthread = _get_curthread(); 65 if ((new_thread = _thr_alloc(curthread)) == NULL) 66 return (EAGAIN); 67 68 memset(¶m, 0, sizeof(param)); 69 70 if (attr == NULL || *attr == NULL) 71 /* Use the default thread attributes: */ 72 new_thread->attr = _pthread_attr_default; 73 else 74 new_thread->attr = *(*attr); 75 if (new_thread->attr.sched_inherit == PTHREAD_INHERIT_SCHED) { 76 /* inherit scheduling contention scope */ 77 if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM) 78 new_thread->attr.flags |= PTHREAD_SCOPE_SYSTEM; 79 else 80 new_thread->attr.flags &= ~PTHREAD_SCOPE_SYSTEM; 81 /* 82 * scheduling policy and scheduling parameters will be 83 * inherited in following code. 84 */ 85 } 86 87 if (_thr_scope_system > 0) 88 new_thread->attr.flags |= PTHREAD_SCOPE_SYSTEM; 89 else if (_thr_scope_system < 0) 90 new_thread->attr.flags &= ~PTHREAD_SCOPE_SYSTEM; 91 92 new_thread->tid = TID_TERMINATED; 93 94 if (create_stack(&new_thread->attr) != 0) { 95 /* Insufficient memory to create a stack: */ 96 _thr_free(curthread, new_thread); 97 return (EAGAIN); 98 } 99 /* 100 * Write a magic value to the thread structure 101 * to help identify valid ones: 102 */ 103 new_thread->magic = THR_MAGIC; 104 new_thread->start_routine = start_routine; 105 new_thread->arg = arg; 106 new_thread->cancelflags = PTHREAD_CANCEL_ENABLE | 107 PTHREAD_CANCEL_DEFERRED; 108 /* 109 * Check if this thread is to inherit the scheduling 110 * attributes from its parent: 111 */ 112 if (new_thread->attr.sched_inherit == PTHREAD_INHERIT_SCHED) { 113 /* 114 * Copy the scheduling attributes. Lock the scheduling 115 * lock to get consistent scheduling parameters. 116 */ 117 THR_LOCK(curthread); 118 new_thread->base_priority = curthread->base_priority; 119 new_thread->attr.prio = curthread->base_priority; 120 new_thread->attr.sched_policy = curthread->attr.sched_policy; 121 THR_UNLOCK(curthread); 122 } else { 123 /* 124 * Use just the thread priority, leaving the 125 * other scheduling attributes as their 126 * default values: 127 */ 128 new_thread->base_priority = new_thread->attr.prio; 129 } 130 new_thread->active_priority = new_thread->base_priority; 131 132 /* Initialize the mutex queue: */ 133 TAILQ_INIT(&new_thread->mutexq); 134 135 /* Initialise hooks in the thread structure: */ 136 if (new_thread->attr.suspend == THR_CREATE_SUSPENDED) { 137 new_thread->flags = THR_FLAGS_NEED_SUSPEND; 138 create_suspended = 1; 139 } else { 140 create_suspended = 0; 141 } 142 143 new_thread->state = PS_RUNNING; 144 145 if (new_thread->attr.flags & PTHREAD_CREATE_DETACHED) 146 new_thread->tlflags |= TLFLAGS_DETACHED; 147 148 /* Add the new thread. */ 149 new_thread->refcount = 1; 150 _thr_link(curthread, new_thread); 151 /* Return thread pointer eariler so that new thread can use it. */ 152 (*thread) = new_thread; 153 if (SHOULD_REPORT_EVENT(curthread, TD_CREATE)) { 154 THR_THREAD_LOCK(curthread, new_thread); 155 locked = 1; 156 } else 157 locked = 0; 158 param.start_func = (void (*)(void *)) thread_start; 159 param.arg = new_thread; 160 param.stack_base = new_thread->attr.stackaddr_attr; 161 param.stack_size = new_thread->attr.stacksize_attr; 162 param.tls_base = (char *)new_thread->tcb; 163 param.tls_size = sizeof(struct tcb); 164 param.child_tid = &new_thread->tid; 165 param.parent_tid = &new_thread->tid; 166 param.flags = 0; 167 if (new_thread->attr.flags & PTHREAD_SCOPE_SYSTEM) 168 param.flags |= THR_SYSTEM_SCOPE; 169 170 /* Schedule the new thread. */ 171 if (create_suspended) { 172 SIGFILLSET(set); 173 SIGDELSET(set, SIGTRAP); 174 __sys_sigprocmask(SIG_SETMASK, &set, &oset); 175 new_thread->sigmask = oset; 176 } 177 178 ret = thr_new(¶m, sizeof(param)); 179 180 if (create_suspended) 181 __sys_sigprocmask(SIG_SETMASK, &oset, NULL); 182 183 if (ret != 0) { 184 if (!locked) 185 THR_THREAD_LOCK(curthread, new_thread); 186 new_thread->state = PS_DEAD; 187 new_thread->tid = TID_TERMINATED; 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) = 0; 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(struct pthread *curthread) 225 { 226 if (curthread->attr.suspend == THR_CREATE_SUSPENDED) { 227 sigset_t set = curthread->sigmask; 228 229 _thr_ast(curthread); 230 231 /* 232 * Parent thread have stored signal mask for us, 233 * we should restore it now. 234 */ 235 sigprocmask(SIG_SETMASK, &set, NULL); 236 } 237 238 /* 239 * This is used as a serialization point to allow parent 240 * to report 'new thread' event to debugger before the thread 241 * does real work. 242 */ 243 THR_LOCK(curthread); 244 THR_UNLOCK(curthread); 245 246 /* Run the current thread's start routine with argument: */ 247 _pthread_exit(curthread->start_routine(curthread->arg)); 248 249 /* This point should never be reached. */ 250 PANIC("Thread has resumed after exit"); 251 } 252