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: releng/10.3/lib/libthr/thread/thr_create.c 277317 2015-01-18 11:54:20Z kib $ 28 */ 29 30#include "namespace.h" 31#include <sys/types.h> 32#include <sys/rtprio.h> 33#include <sys/signalvar.h> 34#include <errno.h> 35#include <link.h> 36#include <stdlib.h> 37#include <string.h> 38#include <stddef.h> 39#include <pthread.h> 40#include <pthread_np.h> 41#include "un-namespace.h" 42 43#include "libc_private.h" 44#include "thr_private.h" 45 46static int create_stack(struct pthread_attr *pattr); 47static void thread_start(struct pthread *curthread); 48 49__weak_reference(_pthread_create, pthread_create); 50 51int 52_pthread_create(pthread_t * thread, const pthread_attr_t * attr, 53 void *(*start_routine) (void *), void *arg) 54{ 55 struct pthread *curthread, *new_thread; 56 struct thr_param param; 57 struct sched_param sched_param; 58 struct rtprio rtp; 59 int ret = 0, locked, create_suspended; 60 sigset_t set, oset; 61 cpuset_t *cpusetp = NULL; 62 int cpusetsize = 0; 63 int old_stack_prot; 64 65 _thr_check_init(); 66 67 /* 68 * Tell libc and others now they need lock to protect their data. 69 */ 70 if (_thr_isthreaded() == 0) { 71 _malloc_first_thread(); 72 if (_thr_setthreaded(1)) 73 return (EAGAIN); 74 } 75 76 curthread = _get_curthread(); 77 if ((new_thread = _thr_alloc(curthread)) == NULL) 78 return (EAGAIN); 79 80 memset(¶m, 0, sizeof(param)); 81 82 if (attr == NULL || *attr == NULL) 83 /* Use the default thread attributes: */ 84 new_thread->attr = _pthread_attr_default; 85 else { 86 new_thread->attr = *(*attr); 87 cpusetp = new_thread->attr.cpuset; 88 cpusetsize = new_thread->attr.cpusetsize; 89 new_thread->attr.cpuset = NULL; 90 new_thread->attr.cpusetsize = 0; 91 } 92 if (new_thread->attr.sched_inherit == PTHREAD_INHERIT_SCHED) { 93 /* inherit scheduling contention scope */ 94 if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM) 95 new_thread->attr.flags |= PTHREAD_SCOPE_SYSTEM; 96 else 97 new_thread->attr.flags &= ~PTHREAD_SCOPE_SYSTEM; 98 99 new_thread->attr.prio = curthread->attr.prio; 100 new_thread->attr.sched_policy = curthread->attr.sched_policy; 101 } 102 103 new_thread->tid = TID_TERMINATED; 104 105 old_stack_prot = _rtld_get_stack_prot(); 106 if (create_stack(&new_thread->attr) != 0) { 107 /* Insufficient memory to create a stack: */ 108 _thr_free(curthread, new_thread); 109 return (EAGAIN); 110 } 111 /* 112 * Write a magic value to the thread structure 113 * to help identify valid ones: 114 */ 115 new_thread->magic = THR_MAGIC; 116 new_thread->start_routine = start_routine; 117 new_thread->arg = arg; 118 new_thread->cancel_enable = 1; 119 new_thread->cancel_async = 0; 120 /* Initialize the mutex queue: */ 121 TAILQ_INIT(&new_thread->mutexq); 122 TAILQ_INIT(&new_thread->pp_mutexq); 123 124 /* Initialise hooks in the thread structure: */ 125 if (new_thread->attr.suspend == THR_CREATE_SUSPENDED) { 126 new_thread->flags = THR_FLAGS_NEED_SUSPEND; 127 create_suspended = 1; 128 } else { 129 create_suspended = 0; 130 } 131 132 new_thread->state = PS_RUNNING; 133 134 if (new_thread->attr.flags & PTHREAD_CREATE_DETACHED) 135 new_thread->flags |= THR_FLAGS_DETACHED; 136 137 /* Add the new thread. */ 138 new_thread->refcount = 1; 139 _thr_link(curthread, new_thread); 140 141 /* 142 * Handle the race between __pthread_map_stacks_exec and 143 * thread linkage. 144 */ 145 if (old_stack_prot != _rtld_get_stack_prot()) 146 _thr_stack_fix_protection(new_thread); 147 148 /* Return thread pointer eariler so that new thread can use it. */ 149 (*thread) = new_thread; 150 if (SHOULD_REPORT_EVENT(curthread, TD_CREATE) || cpusetp != NULL) { 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 if (new_thread->attr.sched_inherit == PTHREAD_INHERIT_SCHED) 167 param.rtp = NULL; 168 else { 169 sched_param.sched_priority = new_thread->attr.prio; 170 _schedparam_to_rtp(new_thread->attr.sched_policy, 171 &sched_param, &rtp); 172 param.rtp = &rtp; 173 } 174 175 /* Schedule the new thread. */ 176 if (create_suspended) { 177 SIGFILLSET(set); 178 SIGDELSET(set, SIGTRAP); 179 __sys_sigprocmask(SIG_SETMASK, &set, &oset); 180 new_thread->sigmask = oset; 181 SIGDELSET(new_thread->sigmask, SIGCANCEL); 182 } 183 184 ret = thr_new(¶m, sizeof(param)); 185 186 if (ret != 0) { 187 ret = errno; 188 /* 189 * Translate EPROCLIM into well-known POSIX code EAGAIN. 190 */ 191 if (ret == EPROCLIM) 192 ret = EAGAIN; 193 } 194 195 if (create_suspended) 196 __sys_sigprocmask(SIG_SETMASK, &oset, NULL); 197 198 if (ret != 0) { 199 if (!locked) 200 THR_THREAD_LOCK(curthread, new_thread); 201 new_thread->state = PS_DEAD; 202 new_thread->tid = TID_TERMINATED; 203 new_thread->flags |= THR_FLAGS_DETACHED; 204 new_thread->refcount--; 205 if (new_thread->flags & THR_FLAGS_NEED_SUSPEND) { 206 new_thread->cycle++; 207 _thr_umtx_wake(&new_thread->cycle, INT_MAX, 0); 208 } 209 _thr_try_gc(curthread, new_thread); /* thread lock released */ 210 atomic_add_int(&_thread_active_threads, -1); 211 } else if (locked) { 212 if (cpusetp != NULL) { 213 if (cpuset_setaffinity(CPU_LEVEL_WHICH, CPU_WHICH_TID, 214 TID(new_thread), cpusetsize, cpusetp)) { 215 ret = errno; 216 /* kill the new thread */ 217 new_thread->force_exit = 1; 218 new_thread->flags |= THR_FLAGS_DETACHED; 219 _thr_try_gc(curthread, new_thread); 220 /* thread lock released */ 221 goto out; 222 } 223 } 224 225 _thr_report_creation(curthread, new_thread); 226 THR_THREAD_UNLOCK(curthread, new_thread); 227 } 228out: 229 if (ret) 230 (*thread) = 0; 231 return (ret); 232} 233 234static int 235create_stack(struct pthread_attr *pattr) 236{ 237 int ret; 238 239 /* Check if a stack was specified in the thread attributes: */ 240 if ((pattr->stackaddr_attr) != NULL) { 241 pattr->guardsize_attr = 0; 242 pattr->flags |= THR_STACK_USER; 243 ret = 0; 244 } 245 else 246 ret = _thr_stack_alloc(pattr); 247 return (ret); 248} 249 250static void 251thread_start(struct pthread *curthread) 252{ 253 sigset_t set; 254 255 if (curthread->attr.suspend == THR_CREATE_SUSPENDED) 256 set = curthread->sigmask; 257 258 /* 259 * This is used as a serialization point to allow parent 260 * to report 'new thread' event to debugger or tweak new thread's 261 * attributes before the new thread does real-world work. 262 */ 263 THR_LOCK(curthread); 264 THR_UNLOCK(curthread); 265 266 if (curthread->force_exit) 267 _pthread_exit(PTHREAD_CANCELED); 268 269 if (curthread->attr.suspend == THR_CREATE_SUSPENDED) { 270#if 0 271 /* Done in THR_UNLOCK() */ 272 _thr_ast(curthread); 273#endif 274 275 /* 276 * Parent thread have stored signal mask for us, 277 * we should restore it now. 278 */ 279 __sys_sigprocmask(SIG_SETMASK, &set, NULL); 280 } 281 282#ifdef _PTHREAD_FORCED_UNWIND 283 curthread->unwind_stackend = (char *)curthread->attr.stackaddr_attr + 284 curthread->attr.stacksize_attr; 285#endif 286 287 /* Run the current thread's start routine with argument: */ 288 _pthread_exit(curthread->start_routine(curthread->arg)); 289 290 /* This point should never be reached. */ 291 PANIC("Thread has resumed after exit"); 292} 293