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(struct pthread_attr *pattr); 48 static void thread_start(void *); 49 50 int 51 _pthread_create(pthread_t * thread, const pthread_attr_t * attr, 52 void *(*start_routine) (void *), void *arg) 53 { 54 struct lwp_params create_params; 55 void *stack; 56 sigset_t sigmask, oldsigmask; 57 struct pthread *curthread, *new_thread; 58 const cpu_set_t *cpumask = NULL; 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 = tls_get_curthread(); 70 if ((new_thread = _thr_alloc(curthread)) == NULL) 71 return (EAGAIN); 72 73 if (attr == NULL || *attr == NULL) { 74 /* Use the default thread attributes: */ 75 new_thread->attr = _pthread_attr_default; 76 } else { 77 new_thread->attr = *(*attr); 78 } 79 if (new_thread->attr.sched_inherit == PTHREAD_INHERIT_SCHED) { 80 /* inherit scheduling contention scope */ 81 if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM) 82 new_thread->attr.flags |= PTHREAD_SCOPE_SYSTEM; 83 else 84 new_thread->attr.flags &= ~PTHREAD_SCOPE_SYSTEM; 85 /* 86 * scheduling policy and scheduling parameters will be 87 * inherited in following code. 88 */ 89 } 90 if (new_thread->attr.flags & THR_CPUMASK) 91 cpumask = &new_thread->attr.cpumask; 92 93 if (create_stack(&new_thread->attr) != 0) { 94 /* Insufficient memory to create a stack: */ 95 new_thread->terminated = 1; 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->attr.prio; 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; 138 139 new_thread->state = PS_RUNNING; 140 141 if (new_thread->attr.flags & PTHREAD_CREATE_DETACHED) 142 new_thread->tlflags |= TLFLAGS_DETACHED; 143 144 /* Add the new thread. */ 145 new_thread->refcount = 1; 146 _thr_link(curthread, new_thread); 147 /* Return thread pointer eariler so that new thread can use it. */ 148 (*thread) = new_thread; 149 if (SHOULD_REPORT_EVENT(curthread, TD_CREATE)) { 150 THR_THREAD_LOCK(curthread, new_thread); 151 locked = 1; 152 } else 153 locked = 0; 154 /* Schedule the new thread. */ 155 stack = (char *)new_thread->attr.stackaddr_attr + 156 new_thread->attr.stacksize_attr; 157 bzero(&create_params, sizeof(create_params)); 158 create_params.lwp_func = thread_start; 159 create_params.lwp_arg = new_thread; 160 create_params.lwp_stack = stack; 161 create_params.lwp_tid1 = &new_thread->tid; 162 /* 163 * Thread created by thr_create() inherits currrent thread 164 * sigmask, however, before new thread setup itself correctly, 165 * it can not handle signal, so we should mask all signals here. 166 * We do this at the very last moment, so that we don't run 167 * into problems while we have all signals disabled. 168 */ 169 SIGFILLSET(sigmask); 170 __sys_sigprocmask(SIG_SETMASK, &sigmask, &oldsigmask); 171 new_thread->sigmask = oldsigmask; 172 ret = lwp_create2(&create_params, cpumask); 173 __sys_sigprocmask(SIG_SETMASK, &oldsigmask, NULL); 174 if (ret != 0) { 175 if (!locked) 176 THR_THREAD_LOCK(curthread, new_thread); 177 new_thread->state = PS_DEAD; 178 new_thread->terminated = 1; 179 if (new_thread->flags & THR_FLAGS_NEED_SUSPEND) { 180 new_thread->cycle++; 181 _thr_umtx_wake(&new_thread->cycle, 0); 182 } 183 THR_THREAD_UNLOCK(curthread, new_thread); 184 THREAD_LIST_LOCK(curthread); 185 _thread_active_threads--; 186 new_thread->tlflags |= TLFLAGS_DETACHED; 187 _thr_ref_delete_unlocked(curthread, new_thread); 188 THREAD_LIST_UNLOCK(curthread); 189 (*thread) = NULL; 190 ret = EAGAIN; 191 } else if (locked) { 192 _thr_report_creation(curthread, new_thread); 193 THR_THREAD_UNLOCK(curthread, new_thread); 194 } 195 return (ret); 196 } 197 198 static int 199 create_stack(struct pthread_attr *pattr) 200 { 201 int ret; 202 203 /* Check if a stack was specified in the thread attributes: */ 204 if ((pattr->stackaddr_attr) != NULL) { 205 pattr->guardsize_attr = 0; 206 pattr->flags |= THR_STACK_USER; 207 ret = 0; 208 } 209 else 210 ret = _thr_stack_alloc(pattr); 211 return (ret); 212 } 213 214 static void 215 thread_start(void *arg) 216 { 217 struct pthread *curthread = (struct pthread *)arg; 218 219 tls_set_tcb(curthread->tcb); 220 221 /* Thread was created with all signals blocked, unblock them. */ 222 __sys_sigprocmask(SIG_SETMASK, &curthread->sigmask, NULL); 223 224 THR_LOCK(curthread); 225 THR_UNLOCK(curthread); 226 227 if (curthread->flags & THR_FLAGS_NEED_SUSPEND) 228 _thr_suspend_check(curthread); 229 _nmalloc_thr_init(); 230 231 /* Run the current thread's start routine with argument: */ 232 _pthread_exit(curthread->start_routine(curthread->arg)); 233 234 /* This point should never be reached. */ 235 PANIC("Thread has resumed after exit"); 236 } 237 238 __strong_reference(_pthread_create, pthread_create); 239