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 #define _WANT_P_OSREL
31 #include "namespace.h"
32 #include <sys/types.h>
33 #include <sys/rtprio.h>
34 #include <sys/signalvar.h>
35 #include <sys/exterrvar.h>
36 #include <errno.h>
37 #include <link.h>
38 #include <stdlib.h>
39 #include <string.h>
40 #include <stddef.h>
41 #include <pthread.h>
42 #include <pthread_np.h>
43 #include "un-namespace.h"
44
45 #include "libc_private.h"
46 #include "thr_private.h"
47
48 int __getosreldate(void);
49
50 static int create_stack(struct pthread_attr *pattr);
51 static void thread_start(struct pthread *curthread);
52
53 int __thr_new_flags = THR_C_RUNTIME;
54
55 __weak_reference(_pthread_create, pthread_create);
56
57 int
_pthread_create(pthread_t * __restrict thread,const pthread_attr_t * __restrict attr,void * (* start_routine)(void *),void * __restrict arg)58 _pthread_create(pthread_t * __restrict thread,
59 const pthread_attr_t * __restrict attr, void *(*start_routine) (void *),
60 void * __restrict arg)
61 {
62 struct pthread *curthread, *new_thread;
63 struct thr_param param;
64 struct sched_param sched_param;
65 struct rtprio rtp;
66 sigset_t set, oset;
67 cpuset_t *cpusetp;
68 int i, cpusetsize, create_suspended, locked, old_stack_prot, ret;
69
70 cpusetp = NULL;
71 ret = cpusetsize = 0;
72 _thr_check_init();
73
74 /*
75 * Tell libc and others now they need lock to protect their data.
76 */
77 if (_thr_isthreaded() == 0) {
78 _malloc_first_thread();
79 _thr_setthreaded(1);
80 }
81
82 curthread = _get_curthread();
83 if ((new_thread = _thr_alloc(curthread)) == NULL)
84 return (EAGAIN);
85
86 memset(¶m, 0, sizeof(param));
87
88 if (attr == NULL || *attr == NULL)
89 /* Use the default thread attributes: */
90 new_thread->attr = _pthread_attr_default;
91 else {
92 new_thread->attr = *(*attr);
93 cpusetp = new_thread->attr.cpuset;
94 cpusetsize = new_thread->attr.cpusetsize;
95 new_thread->attr.cpuset = NULL;
96 new_thread->attr.cpusetsize = 0;
97 }
98 if (new_thread->attr.sched_inherit == PTHREAD_INHERIT_SCHED) {
99 /* inherit scheduling contention scope */
100 if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM)
101 new_thread->attr.flags |= PTHREAD_SCOPE_SYSTEM;
102 else
103 new_thread->attr.flags &= ~PTHREAD_SCOPE_SYSTEM;
104
105 new_thread->attr.prio = curthread->attr.prio;
106 new_thread->attr.sched_policy = curthread->attr.sched_policy;
107 }
108
109 new_thread->tid = TID_TERMINATED;
110
111 old_stack_prot = _rtld_get_stack_prot();
112 if (create_stack(&new_thread->attr) != 0) {
113 /* Insufficient memory to create a stack: */
114 _thr_free(curthread, new_thread);
115 return (EAGAIN);
116 }
117 /*
118 * Write a magic value to the thread structure
119 * to help identify valid ones:
120 */
121 new_thread->magic = THR_MAGIC;
122 new_thread->start_routine = start_routine;
123 new_thread->arg = arg;
124 new_thread->cancel_enable = 1;
125 new_thread->cancel_async = 0;
126 /* Initialize the mutex queue: */
127 for (i = 0; i < TMQ_NITEMS; i++)
128 TAILQ_INIT(&new_thread->mq[i]);
129
130 /* Initialise hooks in the thread structure: */
131 if (new_thread->attr.suspend == THR_CREATE_SUSPENDED) {
132 new_thread->flags = THR_FLAGS_NEED_SUSPEND;
133 create_suspended = 1;
134 } else {
135 create_suspended = 0;
136 }
137
138 new_thread->state = PS_RUNNING;
139
140 if (new_thread->attr.flags & PTHREAD_CREATE_DETACHED)
141 new_thread->flags |= THR_FLAGS_DETACHED;
142
143 /* Add the new thread. */
144 new_thread->refcount = 1;
145 _thr_link(curthread, new_thread);
146
147 /*
148 * Handle the race between __pthread_map_stacks_exec and
149 * thread linkage.
150 */
151 if (old_stack_prot != _rtld_get_stack_prot())
152 _thr_stack_fix_protection(new_thread);
153
154 /* Return thread pointer eariler so that new thread can use it. */
155 *thread = new_thread;
156 if (SHOULD_REPORT_EVENT(curthread, TD_CREATE) || cpusetp != NULL) {
157 THR_THREAD_LOCK(curthread, new_thread);
158 locked = 1;
159 } else
160 locked = 0;
161 param.start_func = (void (*)(void *)) thread_start;
162 param.arg = new_thread;
163 param.stack_base = new_thread->attr.stackaddr_attr;
164 param.stack_size = new_thread->attr.stacksize_attr;
165 param.tls_base = (char *)new_thread->tcb;
166 param.tls_size = sizeof(struct tcb);
167 param.child_tid = &new_thread->tid;
168 param.parent_tid = &new_thread->tid;
169 param.flags = __thr_new_flags;
170 if (new_thread->attr.flags & PTHREAD_SCOPE_SYSTEM)
171 param.flags |= THR_SYSTEM_SCOPE;
172 if (new_thread->attr.sched_inherit == PTHREAD_INHERIT_SCHED)
173 param.rtp = NULL;
174 else {
175 sched_param.sched_priority = new_thread->attr.prio;
176 _schedparam_to_rtp(new_thread->attr.sched_policy,
177 &sched_param, &rtp);
178 param.rtp = &rtp;
179 }
180
181 /* Schedule the new thread. */
182 if (create_suspended) {
183 SIGFILLSET(set);
184 SIGDELSET(set, SIGTRAP);
185 __sys_sigprocmask(SIG_SETMASK, &set, &oset);
186 new_thread->sigmask = oset;
187 SIGDELSET(new_thread->sigmask, SIGCANCEL);
188 }
189
190 ret = thr_new(¶m, sizeof(param));
191
192 if (ret != 0) {
193 ret = errno;
194 /*
195 * Translate EPROCLIM into well-known POSIX code EAGAIN.
196 */
197 if (ret == EPROCLIM)
198 ret = EAGAIN;
199 }
200
201 if (create_suspended)
202 __sys_sigprocmask(SIG_SETMASK, &oset, NULL);
203
204 if (ret != 0) {
205 if (!locked)
206 THR_THREAD_LOCK(curthread, new_thread);
207 new_thread->state = PS_DEAD;
208 new_thread->tid = TID_TERMINATED;
209 new_thread->flags |= THR_FLAGS_DETACHED;
210 new_thread->refcount--;
211 if (new_thread->flags & THR_FLAGS_NEED_SUSPEND) {
212 new_thread->cycle++;
213 _thr_umtx_wake(&new_thread->cycle, INT_MAX, 0);
214 }
215 _thr_try_gc(curthread, new_thread); /* thread lock released */
216 atomic_add_int(&_thread_active_threads, -1);
217 } else if (locked) {
218 if (cpusetp != NULL) {
219 if (cpuset_setaffinity(CPU_LEVEL_WHICH, CPU_WHICH_TID,
220 TID(new_thread), cpusetsize, cpusetp)) {
221 ret = errno;
222 /* kill the new thread */
223 new_thread->force_exit = 1;
224 new_thread->flags |= THR_FLAGS_DETACHED;
225 _thr_try_gc(curthread, new_thread);
226 /* thread lock released */
227 goto out;
228 }
229 }
230
231 _thr_report_creation(curthread, new_thread);
232 THR_THREAD_UNLOCK(curthread, new_thread);
233 }
234 out:
235 if (ret != 0)
236 *thread = NULL;
237 return (ret);
238 }
239
240 static int
create_stack(struct pthread_attr * pattr)241 create_stack(struct pthread_attr *pattr)
242 {
243 int ret;
244
245 /* Check if a stack was specified in the thread attributes: */
246 if ((pattr->stackaddr_attr) != NULL) {
247 pattr->guardsize_attr = 0;
248 pattr->flags |= THR_STACK_USER;
249 ret = 0;
250 }
251 else
252 ret = _thr_stack_alloc(pattr);
253 return (ret);
254 }
255
256 static void
thread_start(struct pthread * curthread)257 thread_start(struct pthread *curthread)
258 {
259 sigset_t set;
260
261 if (curthread->attr.suspend == THR_CREATE_SUSPENDED)
262 set = curthread->sigmask;
263 _thr_signal_block_setup(curthread);
264
265 /*
266 * This is used as a serialization point to allow parent
267 * to report 'new thread' event to debugger or tweak new thread's
268 * attributes before the new thread does real-world work.
269 */
270 THR_LOCK(curthread);
271 THR_UNLOCK(curthread);
272
273 if (curthread->force_exit)
274 _pthread_exit(PTHREAD_CANCELED);
275
276 if (curthread->attr.suspend == THR_CREATE_SUSPENDED) {
277 #if 0
278 /* Done in THR_UNLOCK() */
279 _thr_ast(curthread);
280 #endif
281
282 /*
283 * Parent thread have stored signal mask for us,
284 * we should restore it now.
285 */
286 __sys_sigprocmask(SIG_SETMASK, &set, NULL);
287 }
288
289 #ifdef _PTHREAD_FORCED_UNWIND
290 curthread->unwind_stackend = (char *)curthread->attr.stackaddr_attr +
291 curthread->attr.stacksize_attr;
292 #endif
293
294 curthread->uexterr.ver = UEXTERROR_VER;
295 if (__getosreldate() >= P_OSREL_EXTERRCTL)
296 exterrctl(EXTERRCTL_ENABLE, 0, &curthread->uexterr);
297
298 /* Run the current thread's start routine with argument: */
299 _pthread_exit(curthread->start_routine(curthread->arg));
300
301 /* This point should never be reached. */
302 PANIC("Thread has resumed after exit");
303 }
304