1 /* 2 * Copyright (c) 2005 David Xu <davidxu@freebsd.org> 3 * Copyright (c) 2003 Daniel M. Eischen <deischen@gdeb.com> 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 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 * 26 * $FreeBSD: src/lib/libpthread/thread/thr_create.c,v 1.58 2004/10/23 23:28:36 davidxu Exp $ 27 */ 28 29 #include "namespace.h" 30 #include <errno.h> 31 #include <stdlib.h> 32 #include <string.h> 33 #include <fcntl.h> 34 #include <unistd.h> 35 #include <stddef.h> 36 #include <sys/time.h> 37 #include <machine/reg.h> 38 #include <machine/tls.h> 39 #include <pthread.h> 40 #include <sys/signalvar.h> 41 #include <sys/lwp.h> 42 #include "un-namespace.h" 43 44 #include "libc_private.h" 45 #include "thr_private.h" 46 47 static int create_stack(pthread_attr_t pattr); 48 static void thread_start(void *); 49 50 int 51 _pthread_create(pthread_t * __restrict thread, 52 const pthread_attr_t * __restrict attr, void *(*start_routine) (void *), 53 void * __restrict arg) 54 { 55 struct lwp_params create_params; 56 void *stack; 57 sigset_t sigmask, oldsigmask; 58 pthread_t curthread, new_thread; 59 const cpu_set_t *cpumask = NULL; 60 int ret = 0, locked; 61 62 _thr_check_init(); 63 64 /* 65 * Tell libc and others now they need lock to protect their data. 66 */ 67 if (_thr_isthreaded() == 0 && _thr_setthreaded(1)) 68 return (EAGAIN); 69 70 curthread = tls_get_curthread(); 71 if ((new_thread = _thr_alloc(curthread)) == NULL) 72 return (EAGAIN); 73 74 if (attr == NULL || *attr == NULL) { 75 /* Use the default thread attributes: */ 76 new_thread->attr = _pthread_attr_default; 77 } else { 78 new_thread->attr = *(*attr); 79 } 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 if (new_thread->attr.flags & THR_CPUMASK) 92 cpumask = &new_thread->attr.cpumask; 93 94 if (create_stack(&new_thread->attr) != 0) { 95 /* Insufficient memory to create a stack: */ 96 new_thread->terminated = 1; 97 _thr_free(curthread, new_thread); 98 return (EAGAIN); 99 } 100 /* 101 * Write a magic value to the thread structure 102 * to help identify valid ones: 103 */ 104 new_thread->magic = THR_MAGIC; 105 new_thread->start_routine = start_routine; 106 new_thread->arg = arg; 107 new_thread->cancelflags = PTHREAD_CANCEL_ENABLE | 108 PTHREAD_CANCEL_DEFERRED; 109 /* 110 * Check if this thread is to inherit the scheduling 111 * attributes from its parent: 112 */ 113 if (new_thread->attr.sched_inherit == PTHREAD_INHERIT_SCHED) { 114 /* 115 * Copy the scheduling attributes. Lock the scheduling 116 * lock to get consistent scheduling parameters. 117 */ 118 THR_LOCK(curthread); 119 new_thread->base_priority = curthread->base_priority; 120 new_thread->attr.prio = curthread->attr.prio; 121 new_thread->attr.sched_policy = curthread->attr.sched_policy; 122 THR_UNLOCK(curthread); 123 } else { 124 /* 125 * Use just the thread priority, leaving the 126 * other scheduling attributes as their 127 * default values: 128 */ 129 new_thread->base_priority = new_thread->attr.prio; 130 } 131 new_thread->active_priority = new_thread->base_priority; 132 133 /* Initialize the mutex queue: */ 134 TAILQ_INIT(&new_thread->mutexq); 135 136 /* Initialise hooks in the thread structure: */ 137 if (new_thread->attr.suspend == THR_CREATE_SUSPENDED) 138 new_thread->flags = THR_FLAGS_NEED_SUSPEND; 139 140 new_thread->state = PS_RUNNING; 141 142 if (new_thread->attr.flags & PTHREAD_CREATE_DETACHED) 143 new_thread->tlflags |= TLFLAGS_DETACHED; 144 145 /* Add the new thread. */ 146 new_thread->refcount = 1; 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 /* Schedule the new thread. */ 156 stack = (char *)new_thread->attr.stackaddr_attr + 157 new_thread->attr.stacksize_attr; 158 bzero(&create_params, sizeof(create_params)); 159 create_params.lwp_func = thread_start; 160 create_params.lwp_arg = new_thread; 161 create_params.lwp_stack = stack; 162 create_params.lwp_tid1 = &new_thread->tid; 163 /* 164 * Thread created by thr_create() inherits currrent thread 165 * sigmask, however, before new thread setup itself correctly, 166 * it can not handle signal, so we should mask all signals here. 167 * We do this at the very last moment, so that we don't run 168 * into problems while we have all signals disabled. 169 */ 170 SIGFILLSET(sigmask); 171 __sys_sigprocmask(SIG_SETMASK, &sigmask, &oldsigmask); 172 new_thread->sigmask = oldsigmask; 173 ret = lwp_create2(&create_params, cpumask); 174 __sys_sigprocmask(SIG_SETMASK, &oldsigmask, NULL); 175 if (ret != 0) { 176 if (!locked) 177 THR_THREAD_LOCK(curthread, new_thread); 178 new_thread->state = PS_DEAD; 179 new_thread->terminated = 1; 180 if (new_thread->flags & THR_FLAGS_NEED_SUSPEND) { 181 new_thread->cycle++; 182 _thr_umtx_wake(&new_thread->cycle, 0); 183 } 184 THR_THREAD_UNLOCK(curthread, new_thread); 185 THREAD_LIST_LOCK(curthread); 186 _thread_active_threads--; 187 new_thread->tlflags |= TLFLAGS_DETACHED; 188 _thr_ref_delete_unlocked(curthread, new_thread); 189 THREAD_LIST_UNLOCK(curthread); 190 (*thread) = NULL; 191 ret = EAGAIN; 192 } else if (locked) { 193 _thr_report_creation(curthread, new_thread); 194 THR_THREAD_UNLOCK(curthread, new_thread); 195 } 196 return (ret); 197 } 198 199 static int 200 create_stack(pthread_attr_t pattr) 201 { 202 int ret; 203 204 /* Check if a stack was specified in the thread attributes: */ 205 if ((pattr->stackaddr_attr) != NULL) { 206 pattr->guardsize_attr = 0; 207 pattr->flags |= THR_STACK_USER; 208 ret = 0; 209 } 210 else 211 ret = _thr_stack_alloc(pattr); 212 return (ret); 213 } 214 215 static void 216 thread_start(void *arg) 217 { 218 pthread_t curthread = (pthread_t)arg; 219 220 tls_set_tcb(curthread->tcb); 221 222 /* Thread was created with all signals blocked, unblock them. */ 223 __sys_sigprocmask(SIG_SETMASK, &curthread->sigmask, NULL); 224 225 THR_LOCK(curthread); 226 THR_UNLOCK(curthread); 227 228 if (curthread->flags & THR_FLAGS_NEED_SUSPEND) 229 _thr_suspend_check(curthread); 230 _libc_thr_init(); 231 232 /* Run the current thread's start routine with argument: */ 233 _pthread_exit(curthread->start_routine(curthread->arg)); 234 235 /* This point should never be reached. */ 236 PANIC("Thread has resumed after exit"); 237 } 238 239 __strong_reference(_pthread_create, pthread_create); 240