1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2003 Daniel M. Eischen <[email protected]>
5 * Copyright (c) 2005, David Xu <[email protected]>
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
_pthread_create(pthread_t * __restrict thread,const pthread_attr_t * __restrict attr,void * (* start_routine)(void *),void * __restrict arg)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
create_stack(struct pthread_attr * pattr)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
thread_start(struct pthread * curthread)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 _thr_signal_block_setup(curthread);
261
262 /*
263 * This is used as a serialization point to allow parent
264 * to report 'new thread' event to debugger or tweak new thread's
265 * attributes before the new thread does real-world work.
266 */
267 THR_LOCK(curthread);
268 THR_UNLOCK(curthread);
269
270 if (curthread->force_exit)
271 _pthread_exit(PTHREAD_CANCELED);
272
273 if (curthread->attr.suspend == THR_CREATE_SUSPENDED) {
274 #if 0
275 /* Done in THR_UNLOCK() */
276 _thr_ast(curthread);
277 #endif
278
279 /*
280 * Parent thread have stored signal mask for us,
281 * we should restore it now.
282 */
283 __sys_sigprocmask(SIG_SETMASK, &set, NULL);
284 }
285
286 #ifdef _PTHREAD_FORCED_UNWIND
287 curthread->unwind_stackend = (char *)curthread->attr.stackaddr_attr +
288 curthread->attr.stacksize_attr;
289 #endif
290
291 /* Run the current thread's start routine with argument: */
292 _pthread_exit(curthread->start_routine(curthread->arg));
293
294 /* This point should never be reached. */
295 PANIC("Thread has resumed after exit");
296 }
297