1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2003 Daniel M. Eischen <deischen@gdeb.com> 5 * Copyright (c) 2005, David Xu <davidxu@freebsd.org> 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice unmodified, this list of conditions, and the following 13 * disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28 */ 29 30 #include <sys/cdefs.h> 31 __FBSDID("$FreeBSD$"); 32 33 #include "namespace.h" 34 #include <sys/types.h> 35 #include <sys/rtprio.h> 36 #include <sys/signalvar.h> 37 #include <errno.h> 38 #include <link.h> 39 #include <stdlib.h> 40 #include <string.h> 41 #include <stddef.h> 42 #include <pthread.h> 43 #include <pthread_np.h> 44 #include "un-namespace.h" 45 46 #include "libc_private.h" 47 #include "thr_private.h" 48 49 static int create_stack(struct pthread_attr *pattr); 50 static void thread_start(struct pthread *curthread); 51 52 __weak_reference(_pthread_create, pthread_create); 53 54 int 55 _pthread_create(pthread_t * __restrict thread, 56 const pthread_attr_t * __restrict attr, void *(*start_routine) (void *), 57 void * __restrict arg) 58 { 59 struct pthread *curthread, *new_thread; 60 struct thr_param param; 61 struct sched_param sched_param; 62 struct rtprio rtp; 63 sigset_t set, oset; 64 cpuset_t *cpusetp; 65 int i, cpusetsize, create_suspended, locked, old_stack_prot, ret; 66 67 cpusetp = NULL; 68 ret = cpusetsize = 0; 69 _thr_check_init(); 70 71 /* 72 * Tell libc and others now they need lock to protect their data. 73 */ 74 if (_thr_isthreaded() == 0) { 75 _malloc_first_thread(); 76 _thr_setthreaded(1); 77 } 78 79 curthread = _get_curthread(); 80 if ((new_thread = _thr_alloc(curthread)) == NULL) 81 return (EAGAIN); 82 83 memset(¶m, 0, sizeof(param)); 84 85 if (attr == NULL || *attr == NULL) 86 /* Use the default thread attributes: */ 87 new_thread->attr = _pthread_attr_default; 88 else { 89 new_thread->attr = *(*attr); 90 cpusetp = new_thread->attr.cpuset; 91 cpusetsize = new_thread->attr.cpusetsize; 92 new_thread->attr.cpuset = NULL; 93 new_thread->attr.cpusetsize = 0; 94 } 95 if (new_thread->attr.sched_inherit == PTHREAD_INHERIT_SCHED) { 96 /* inherit scheduling contention scope */ 97 if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM) 98 new_thread->attr.flags |= PTHREAD_SCOPE_SYSTEM; 99 else 100 new_thread->attr.flags &= ~PTHREAD_SCOPE_SYSTEM; 101 102 new_thread->attr.prio = curthread->attr.prio; 103 new_thread->attr.sched_policy = curthread->attr.sched_policy; 104 } 105 106 new_thread->tid = TID_TERMINATED; 107 108 old_stack_prot = _rtld_get_stack_prot(); 109 if (create_stack(&new_thread->attr) != 0) { 110 /* Insufficient memory to create a stack: */ 111 _thr_free(curthread, new_thread); 112 return (EAGAIN); 113 } 114 /* 115 * Write a magic value to the thread structure 116 * to help identify valid ones: 117 */ 118 new_thread->magic = THR_MAGIC; 119 new_thread->start_routine = start_routine; 120 new_thread->arg = arg; 121 new_thread->cancel_enable = 1; 122 new_thread->cancel_async = 0; 123 /* Initialize the mutex queue: */ 124 for (i = 0; i < TMQ_NITEMS; i++) 125 TAILQ_INIT(&new_thread->mq[i]); 126 127 /* Initialise hooks in the thread structure: */ 128 if (new_thread->attr.suspend == THR_CREATE_SUSPENDED) { 129 new_thread->flags = THR_FLAGS_NEED_SUSPEND; 130 create_suspended = 1; 131 } else { 132 create_suspended = 0; 133 } 134 135 new_thread->state = PS_RUNNING; 136 137 if (new_thread->attr.flags & PTHREAD_CREATE_DETACHED) 138 new_thread->flags |= THR_FLAGS_DETACHED; 139 140 /* Add the new thread. */ 141 new_thread->refcount = 1; 142 _thr_link(curthread, new_thread); 143 144 /* 145 * Handle the race between __pthread_map_stacks_exec and 146 * thread linkage. 147 */ 148 if (old_stack_prot != _rtld_get_stack_prot()) 149 _thr_stack_fix_protection(new_thread); 150 151 /* Return thread pointer eariler so that new thread can use it. */ 152 (*thread) = new_thread; 153 if (SHOULD_REPORT_EVENT(curthread, TD_CREATE) || cpusetp != NULL) { 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 if (new_thread->attr.sched_inherit == PTHREAD_INHERIT_SCHED) 170 param.rtp = NULL; 171 else { 172 sched_param.sched_priority = new_thread->attr.prio; 173 _schedparam_to_rtp(new_thread->attr.sched_policy, 174 &sched_param, &rtp); 175 param.rtp = &rtp; 176 } 177 178 /* Schedule the new thread. */ 179 if (create_suspended) { 180 SIGFILLSET(set); 181 SIGDELSET(set, SIGTRAP); 182 __sys_sigprocmask(SIG_SETMASK, &set, &oset); 183 new_thread->sigmask = oset; 184 SIGDELSET(new_thread->sigmask, SIGCANCEL); 185 } 186 187 ret = thr_new(¶m, sizeof(param)); 188 189 if (ret != 0) { 190 ret = errno; 191 /* 192 * Translate EPROCLIM into well-known POSIX code EAGAIN. 193 */ 194 if (ret == EPROCLIM) 195 ret = EAGAIN; 196 } 197 198 if (create_suspended) 199 __sys_sigprocmask(SIG_SETMASK, &oset, NULL); 200 201 if (ret != 0) { 202 if (!locked) 203 THR_THREAD_LOCK(curthread, new_thread); 204 new_thread->state = PS_DEAD; 205 new_thread->tid = TID_TERMINATED; 206 new_thread->flags |= THR_FLAGS_DETACHED; 207 new_thread->refcount--; 208 if (new_thread->flags & THR_FLAGS_NEED_SUSPEND) { 209 new_thread->cycle++; 210 _thr_umtx_wake(&new_thread->cycle, INT_MAX, 0); 211 } 212 _thr_try_gc(curthread, new_thread); /* thread lock released */ 213 atomic_add_int(&_thread_active_threads, -1); 214 } else if (locked) { 215 if (cpusetp != NULL) { 216 if (cpuset_setaffinity(CPU_LEVEL_WHICH, CPU_WHICH_TID, 217 TID(new_thread), cpusetsize, cpusetp)) { 218 ret = errno; 219 /* kill the new thread */ 220 new_thread->force_exit = 1; 221 new_thread->flags |= THR_FLAGS_DETACHED; 222 _thr_try_gc(curthread, new_thread); 223 /* thread lock released */ 224 goto out; 225 } 226 } 227 228 _thr_report_creation(curthread, new_thread); 229 THR_THREAD_UNLOCK(curthread, new_thread); 230 } 231 out: 232 if (ret) 233 (*thread) = 0; 234 return (ret); 235 } 236 237 static int 238 create_stack(struct pthread_attr *pattr) 239 { 240 int ret; 241 242 /* Check if a stack was specified in the thread attributes: */ 243 if ((pattr->stackaddr_attr) != NULL) { 244 pattr->guardsize_attr = 0; 245 pattr->flags |= THR_STACK_USER; 246 ret = 0; 247 } 248 else 249 ret = _thr_stack_alloc(pattr); 250 return (ret); 251 } 252 253 static void 254 thread_start(struct pthread *curthread) 255 { 256 sigset_t set; 257 258 if (curthread->attr.suspend == THR_CREATE_SUSPENDED) 259 set = curthread->sigmask; 260 261 /* 262 * This is used as a serialization point to allow parent 263 * to report 'new thread' event to debugger or tweak new thread's 264 * attributes before the new thread does real-world work. 265 */ 266 THR_LOCK(curthread); 267 THR_UNLOCK(curthread); 268 269 if (curthread->force_exit) 270 _pthread_exit(PTHREAD_CANCELED); 271 272 if (curthread->attr.suspend == THR_CREATE_SUSPENDED) { 273 #if 0 274 /* Done in THR_UNLOCK() */ 275 _thr_ast(curthread); 276 #endif 277 278 /* 279 * Parent thread have stored signal mask for us, 280 * we should restore it now. 281 */ 282 __sys_sigprocmask(SIG_SETMASK, &set, NULL); 283 } 284 285 #ifdef _PTHREAD_FORCED_UNWIND 286 curthread->unwind_stackend = (char *)curthread->attr.stackaddr_attr + 287 curthread->attr.stacksize_attr; 288 #endif 289 290 /* Run the current thread's start routine with argument: */ 291 _pthread_exit(curthread->start_routine(curthread->arg)); 292 293 /* This point should never be reached. */ 294 PANIC("Thread has resumed after exit"); 295 } 296