thr_create.c revision 338707
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 28#include <sys/cdefs.h> 29__FBSDID("$FreeBSD: stable/11/lib/libthr/thread/thr_create.c 338707 2018-09-17 02:51:08Z pfg $"); 30 31#include "namespace.h" 32#include <sys/types.h> 33#include <sys/rtprio.h> 34#include <sys/signalvar.h> 35#include <errno.h> 36#include <link.h> 37#include <stdlib.h> 38#include <string.h> 39#include <stddef.h> 40#include <pthread.h> 41#include <pthread_np.h> 42#include "un-namespace.h" 43 44#include "libc_private.h" 45#include "thr_private.h" 46 47static int create_stack(struct pthread_attr *pattr); 48static void thread_start(struct pthread *curthread); 49 50__weak_reference(_pthread_create, pthread_create); 51 52int 53_pthread_create(pthread_t * __restrict thread, 54 const pthread_attr_t * __restrict attr, void *(*start_routine) (void *), 55 void * __restrict arg) 56{ 57 struct pthread *curthread, *new_thread; 58 struct thr_param param; 59 struct sched_param sched_param; 60 struct rtprio rtp; 61 sigset_t set, oset; 62 cpuset_t *cpusetp; 63 int i, cpusetsize, create_suspended, locked, old_stack_prot, ret; 64 65 cpusetp = NULL; 66 ret = cpusetsize = 0; 67 _thr_check_init(); 68 69 /* 70 * Tell libc and others now they need lock to protect their data. 71 */ 72 if (_thr_isthreaded() == 0) { 73 _malloc_first_thread(); 74 if (_thr_setthreaded(1)) 75 return (EAGAIN); 76 } 77 78 curthread = _get_curthread(); 79 if ((new_thread = _thr_alloc(curthread)) == NULL) 80 return (EAGAIN); 81 82 memset(¶m, 0, sizeof(param)); 83 84 if (attr == NULL || *attr == NULL) 85 /* Use the default thread attributes: */ 86 new_thread->attr = _pthread_attr_default; 87 else { 88 new_thread->attr = *(*attr); 89 cpusetp = new_thread->attr.cpuset; 90 cpusetsize = new_thread->attr.cpusetsize; 91 new_thread->attr.cpuset = NULL; 92 new_thread->attr.cpusetsize = 0; 93 } 94 if (new_thread->attr.sched_inherit == PTHREAD_INHERIT_SCHED) { 95 /* inherit scheduling contention scope */ 96 if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM) 97 new_thread->attr.flags |= PTHREAD_SCOPE_SYSTEM; 98 else 99 new_thread->attr.flags &= ~PTHREAD_SCOPE_SYSTEM; 100 101 new_thread->attr.prio = curthread->attr.prio; 102 new_thread->attr.sched_policy = curthread->attr.sched_policy; 103 } 104 105 new_thread->tid = TID_TERMINATED; 106 107 old_stack_prot = _rtld_get_stack_prot(); 108 if (create_stack(&new_thread->attr) != 0) { 109 /* Insufficient memory to create a stack: */ 110 _thr_free(curthread, new_thread); 111 return (EAGAIN); 112 } 113 /* 114 * Write a magic value to the thread structure 115 * to help identify valid ones: 116 */ 117 new_thread->magic = THR_MAGIC; 118 new_thread->start_routine = start_routine; 119 new_thread->arg = arg; 120 new_thread->cancel_enable = 1; 121 new_thread->cancel_async = 0; 122 /* Initialize the mutex queue: */ 123 for (i = 0; i < TMQ_NITEMS; i++) 124 TAILQ_INIT(&new_thread->mq[i]); 125 126 /* Initialise hooks in the thread structure: */ 127 if (new_thread->attr.suspend == THR_CREATE_SUSPENDED) { 128 new_thread->flags = THR_FLAGS_NEED_SUSPEND; 129 create_suspended = 1; 130 } else { 131 create_suspended = 0; 132 } 133 134 new_thread->state = PS_RUNNING; 135 136 if (new_thread->attr.flags & PTHREAD_CREATE_DETACHED) 137 new_thread->flags |= THR_FLAGS_DETACHED; 138 139 /* Add the new thread. */ 140 new_thread->refcount = 1; 141 _thr_link(curthread, new_thread); 142 143 /* 144 * Handle the race between __pthread_map_stacks_exec and 145 * thread linkage. 146 */ 147 if (old_stack_prot != _rtld_get_stack_prot()) 148 _thr_stack_fix_protection(new_thread); 149 150 /* Return thread pointer eariler so that new thread can use it. */ 151 (*thread) = new_thread; 152 if (SHOULD_REPORT_EVENT(curthread, TD_CREATE) || cpusetp != NULL) { 153 THR_THREAD_LOCK(curthread, new_thread); 154 locked = 1; 155 } else 156 locked = 0; 157 param.start_func = (void (*)(void *)) thread_start; 158 param.arg = new_thread; 159 param.stack_base = new_thread->attr.stackaddr_attr; 160 param.stack_size = new_thread->attr.stacksize_attr; 161 param.tls_base = (char *)new_thread->tcb; 162 param.tls_size = sizeof(struct tcb); 163 param.child_tid = &new_thread->tid; 164 param.parent_tid = &new_thread->tid; 165 param.flags = 0; 166 if (new_thread->attr.flags & PTHREAD_SCOPE_SYSTEM) 167 param.flags |= THR_SYSTEM_SCOPE; 168 if (new_thread->attr.sched_inherit == PTHREAD_INHERIT_SCHED) 169 param.rtp = NULL; 170 else { 171 sched_param.sched_priority = new_thread->attr.prio; 172 _schedparam_to_rtp(new_thread->attr.sched_policy, 173 &sched_param, &rtp); 174 param.rtp = &rtp; 175 } 176 177 /* Schedule the new thread. */ 178 if (create_suspended) { 179 SIGFILLSET(set); 180 SIGDELSET(set, SIGTRAP); 181 __sys_sigprocmask(SIG_SETMASK, &set, &oset); 182 new_thread->sigmask = oset; 183 SIGDELSET(new_thread->sigmask, SIGCANCEL); 184 } 185 186 ret = thr_new(¶m, sizeof(param)); 187 188 if (ret != 0) { 189 ret = errno; 190 /* 191 * Translate EPROCLIM into well-known POSIX code EAGAIN. 192 */ 193 if (ret == EPROCLIM) 194 ret = EAGAIN; 195 } 196 197 if (create_suspended) 198 __sys_sigprocmask(SIG_SETMASK, &oset, NULL); 199 200 if (ret != 0) { 201 if (!locked) 202 THR_THREAD_LOCK(curthread, new_thread); 203 new_thread->state = PS_DEAD; 204 new_thread->tid = TID_TERMINATED; 205 new_thread->flags |= THR_FLAGS_DETACHED; 206 new_thread->refcount--; 207 if (new_thread->flags & THR_FLAGS_NEED_SUSPEND) { 208 new_thread->cycle++; 209 _thr_umtx_wake(&new_thread->cycle, INT_MAX, 0); 210 } 211 _thr_try_gc(curthread, new_thread); /* thread lock released */ 212 atomic_add_int(&_thread_active_threads, -1); 213 } else if (locked) { 214 if (cpusetp != NULL) { 215 if (cpuset_setaffinity(CPU_LEVEL_WHICH, CPU_WHICH_TID, 216 TID(new_thread), cpusetsize, cpusetp)) { 217 ret = errno; 218 /* kill the new thread */ 219 new_thread->force_exit = 1; 220 new_thread->flags |= THR_FLAGS_DETACHED; 221 _thr_try_gc(curthread, new_thread); 222 /* thread lock released */ 223 goto out; 224 } 225 } 226 227 _thr_report_creation(curthread, new_thread); 228 THR_THREAD_UNLOCK(curthread, new_thread); 229 } 230out: 231 if (ret) 232 (*thread) = 0; 233 return (ret); 234} 235 236static int 237create_stack(struct pthread_attr *pattr) 238{ 239 int ret; 240 241 /* Check if a stack was specified in the thread attributes: */ 242 if ((pattr->stackaddr_attr) != NULL) { 243 pattr->guardsize_attr = 0; 244 pattr->flags |= THR_STACK_USER; 245 ret = 0; 246 } 247 else 248 ret = _thr_stack_alloc(pattr); 249 return (ret); 250} 251 252static void 253thread_start(struct pthread *curthread) 254{ 255 sigset_t set; 256 257 if (curthread->attr.suspend == THR_CREATE_SUSPENDED) 258 set = curthread->sigmask; 259 260 /* 261 * This is used as a serialization point to allow parent 262 * to report 'new thread' event to debugger or tweak new thread's 263 * attributes before the new thread does real-world work. 264 */ 265 THR_LOCK(curthread); 266 THR_UNLOCK(curthread); 267 268 if (curthread->force_exit) 269 _pthread_exit(PTHREAD_CANCELED); 270 271 if (curthread->attr.suspend == THR_CREATE_SUSPENDED) { 272#if 0 273 /* Done in THR_UNLOCK() */ 274 _thr_ast(curthread); 275#endif 276 277 /* 278 * Parent thread have stored signal mask for us, 279 * we should restore it now. 280 */ 281 __sys_sigprocmask(SIG_SETMASK, &set, NULL); 282 } 283 284#ifdef _PTHREAD_FORCED_UNWIND 285 curthread->unwind_stackend = (char *)curthread->attr.stackaddr_attr + 286 curthread->attr.stacksize_attr; 287#endif 288 289 /* Run the current thread's start routine with argument: */ 290 _pthread_exit(curthread->start_routine(curthread->arg)); 291 292 /* This point should never be reached. */ 293 PANIC("Thread has resumed after exit"); 294} 295