1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 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 #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 47 static int create_stack(struct pthread_attr *pattr); 48 static void thread_start(struct pthread *curthread); 49 50 __weak_reference(_pthread_create, pthread_create); 51 52 int 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 _thr_setthreaded(1); 75 } 76 77 curthread = _get_curthread(); 78 if ((new_thread = _thr_alloc(curthread)) == NULL) 79 return (EAGAIN); 80 81 memset(¶m, 0, sizeof(param)); 82 83 if (attr == NULL || *attr == NULL) 84 /* Use the default thread attributes: */ 85 new_thread->attr = _pthread_attr_default; 86 else { 87 new_thread->attr = *(*attr); 88 cpusetp = new_thread->attr.cpuset; 89 cpusetsize = new_thread->attr.cpusetsize; 90 new_thread->attr.cpuset = NULL; 91 new_thread->attr.cpusetsize = 0; 92 } 93 if (new_thread->attr.sched_inherit == PTHREAD_INHERIT_SCHED) { 94 /* inherit scheduling contention scope */ 95 if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM) 96 new_thread->attr.flags |= PTHREAD_SCOPE_SYSTEM; 97 else 98 new_thread->attr.flags &= ~PTHREAD_SCOPE_SYSTEM; 99 100 new_thread->attr.prio = curthread->attr.prio; 101 new_thread->attr.sched_policy = curthread->attr.sched_policy; 102 } 103 104 new_thread->tid = TID_TERMINATED; 105 106 old_stack_prot = _rtld_get_stack_prot(); 107 if (create_stack(&new_thread->attr) != 0) { 108 /* Insufficient memory to create a stack: */ 109 _thr_free(curthread, new_thread); 110 return (EAGAIN); 111 } 112 /* 113 * Write a magic value to the thread structure 114 * to help identify valid ones: 115 */ 116 new_thread->magic = THR_MAGIC; 117 new_thread->start_routine = start_routine; 118 new_thread->arg = arg; 119 new_thread->cancel_enable = 1; 120 new_thread->cancel_async = 0; 121 /* Initialize the mutex queue: */ 122 for (i = 0; i < TMQ_NITEMS; i++) 123 TAILQ_INIT(&new_thread->mq[i]); 124 125 /* Initialise hooks in the thread structure: */ 126 if (new_thread->attr.suspend == THR_CREATE_SUSPENDED) { 127 new_thread->flags = THR_FLAGS_NEED_SUSPEND; 128 create_suspended = 1; 129 } else { 130 create_suspended = 0; 131 } 132 133 new_thread->state = PS_RUNNING; 134 135 if (new_thread->attr.flags & PTHREAD_CREATE_DETACHED) 136 new_thread->flags |= THR_FLAGS_DETACHED; 137 138 /* Add the new thread. */ 139 new_thread->refcount = 1; 140 _thr_link(curthread, new_thread); 141 142 /* 143 * Handle the race between __pthread_map_stacks_exec and 144 * thread linkage. 145 */ 146 if (old_stack_prot != _rtld_get_stack_prot()) 147 _thr_stack_fix_protection(new_thread); 148 149 /* Return thread pointer eariler so that new thread can use it. */ 150 (*thread) = new_thread; 151 if (SHOULD_REPORT_EVENT(curthread, TD_CREATE) || cpusetp != NULL) { 152 THR_THREAD_LOCK(curthread, new_thread); 153 locked = 1; 154 } else 155 locked = 0; 156 param.start_func = (void (*)(void *)) thread_start; 157 param.arg = new_thread; 158 param.stack_base = new_thread->attr.stackaddr_attr; 159 param.stack_size = new_thread->attr.stacksize_attr; 160 param.tls_base = (char *)new_thread->tcb; 161 param.tls_size = sizeof(struct tcb); 162 param.child_tid = &new_thread->tid; 163 param.parent_tid = &new_thread->tid; 164 param.flags = 0; 165 if (new_thread->attr.flags & PTHREAD_SCOPE_SYSTEM) 166 param.flags |= THR_SYSTEM_SCOPE; 167 if (new_thread->attr.sched_inherit == PTHREAD_INHERIT_SCHED) 168 param.rtp = NULL; 169 else { 170 sched_param.sched_priority = new_thread->attr.prio; 171 _schedparam_to_rtp(new_thread->attr.sched_policy, 172 &sched_param, &rtp); 173 param.rtp = &rtp; 174 } 175 176 /* Schedule the new thread. */ 177 if (create_suspended) { 178 SIGFILLSET(set); 179 SIGDELSET(set, SIGTRAP); 180 __sys_sigprocmask(SIG_SETMASK, &set, &oset); 181 new_thread->sigmask = oset; 182 SIGDELSET(new_thread->sigmask, SIGCANCEL); 183 } 184 185 ret = thr_new(¶m, sizeof(param)); 186 187 if (ret != 0) { 188 ret = errno; 189 /* 190 * Translate EPROCLIM into well-known POSIX code EAGAIN. 191 */ 192 if (ret == EPROCLIM) 193 ret = EAGAIN; 194 } 195 196 if (create_suspended) 197 __sys_sigprocmask(SIG_SETMASK, &oset, NULL); 198 199 if (ret != 0) { 200 if (!locked) 201 THR_THREAD_LOCK(curthread, new_thread); 202 new_thread->state = PS_DEAD; 203 new_thread->tid = TID_TERMINATED; 204 new_thread->flags |= THR_FLAGS_DETACHED; 205 new_thread->refcount--; 206 if (new_thread->flags & THR_FLAGS_NEED_SUSPEND) { 207 new_thread->cycle++; 208 _thr_umtx_wake(&new_thread->cycle, INT_MAX, 0); 209 } 210 _thr_try_gc(curthread, new_thread); /* thread lock released */ 211 atomic_add_int(&_thread_active_threads, -1); 212 } else if (locked) { 213 if (cpusetp != NULL) { 214 if (cpuset_setaffinity(CPU_LEVEL_WHICH, CPU_WHICH_TID, 215 TID(new_thread), cpusetsize, cpusetp)) { 216 ret = errno; 217 /* kill the new thread */ 218 new_thread->force_exit = 1; 219 new_thread->flags |= THR_FLAGS_DETACHED; 220 _thr_try_gc(curthread, new_thread); 221 /* thread lock released */ 222 goto out; 223 } 224 } 225 226 _thr_report_creation(curthread, new_thread); 227 THR_THREAD_UNLOCK(curthread, new_thread); 228 } 229 out: 230 if (ret) 231 (*thread) = 0; 232 return (ret); 233 } 234 235 static int 236 create_stack(struct pthread_attr *pattr) 237 { 238 int ret; 239 240 /* Check if a stack was specified in the thread attributes: */ 241 if ((pattr->stackaddr_attr) != NULL) { 242 pattr->guardsize_attr = 0; 243 pattr->flags |= THR_STACK_USER; 244 ret = 0; 245 } 246 else 247 ret = _thr_stack_alloc(pattr); 248 return (ret); 249 } 250 251 static void 252 thread_start(struct pthread *curthread) 253 { 254 sigset_t set; 255 256 if (curthread->attr.suspend == THR_CREATE_SUSPENDED) 257 set = curthread->sigmask; 258 _thr_signal_block_setup(curthread); 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