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 * $FreeBSD: head/lib/libthr/thread/thr_create.c 212076 2010-09-01 02:18:33Z davidxu $
28 */
29
30#include "namespace.h"
31#include <sys/types.h>
32#include <sys/rtprio.h>
33#include <sys/signalvar.h>
34#include <errno.h>
35#include <stdlib.h>
36#include <string.h>
37#include <stddef.h>
38#include <pthread.h>
39#include <pthread_np.h>
40#include "un-namespace.h"
41
42#include "thr_private.h"
43
44static int create_stack(struct pthread_attr *pattr);
45static void thread_start(struct pthread *curthread);
46
47__weak_reference(_pthread_create, pthread_create);
48
49int
50_pthread_create(pthread_t * thread, const pthread_attr_t * attr,
51 void *(*start_routine) (void *), void *arg)
52{
53 struct pthread *curthread, *new_thread;
54 struct thr_param param;
55 struct sched_param sched_param;
56 struct rtprio rtp;
57 int ret = 0, locked, create_suspended;
58 sigset_t set, oset;
59 cpuset_t *cpusetp = NULL;
60 int cpusetsize = 0;
61
62 _thr_check_init();
63
64 /*
65 * Tell libc and others now they need lock to protect their data.
66 */
67 if (_thr_isthreaded() == 0 && _thr_setthreaded(1))
68 return (EAGAIN);
69
70 curthread = _get_curthread();
71 if ((new_thread = _thr_alloc(curthread)) == NULL)
72 return (EAGAIN);
73
74 memset(&param, 0, sizeof(param));
75
76 if (attr == NULL || *attr == NULL)
77 /* Use the default thread attributes: */
78 new_thread->attr = _pthread_attr_default;
79 else {
80 new_thread->attr = *(*attr);
81 cpusetp = new_thread->attr.cpuset;
82 cpusetsize = new_thread->attr.cpusetsize;
83 new_thread->attr.cpuset = NULL;
84 new_thread->attr.cpusetsize = 0;
85 }
86 if (new_thread->attr.sched_inherit == PTHREAD_INHERIT_SCHED) {
87 /* inherit scheduling contention scope */
88 if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM)
89 new_thread->attr.flags |= PTHREAD_SCOPE_SYSTEM;
90 else
91 new_thread->attr.flags &= ~PTHREAD_SCOPE_SYSTEM;
92
93 new_thread->attr.prio = curthread->attr.prio;
94 new_thread->attr.sched_policy = curthread->attr.sched_policy;
95 }
96
97 new_thread->tid = TID_TERMINATED;
98
99 if (create_stack(&new_thread->attr) != 0) {
100 /* Insufficient memory to create a stack: */
101 _thr_free(curthread, new_thread);
102 return (EAGAIN);
103 }
104 /*
105 * Write a magic value to the thread structure
106 * to help identify valid ones:
107 */
108 new_thread->magic = THR_MAGIC;
109 new_thread->start_routine = start_routine;
110 new_thread->arg = arg;
111 new_thread->cancel_enable = 1;
112 new_thread->cancel_async = 0;
113 /* Initialize the mutex queue: */
114 TAILQ_INIT(&new_thread->mutexq);
115 TAILQ_INIT(&new_thread->pp_mutexq);
116
117 /* Initialise hooks in the thread structure: */
118 if (new_thread->attr.suspend == THR_CREATE_SUSPENDED) {
119 new_thread->flags = THR_FLAGS_NEED_SUSPEND;
120 create_suspended = 1;
121 } else {
122 create_suspended = 0;
123 }
124
125 new_thread->state = PS_RUNNING;
126
127 if (new_thread->attr.flags & PTHREAD_CREATE_DETACHED)
128 new_thread->tlflags |= TLFLAGS_DETACHED;
129
130 /* Add the new thread. */
131 new_thread->refcount = 1;
132 _thr_link(curthread, new_thread);
133 /* Return thread pointer eariler so that new thread can use it. */
134 (*thread) = new_thread;
135 if (SHOULD_REPORT_EVENT(curthread, TD_CREATE) || cpusetp != NULL) {
136 THR_THREAD_LOCK(curthread, new_thread);
137 locked = 1;
138 } else
139 locked = 0;
140 param.start_func = (void (*)(void *)) thread_start;
141 param.arg = new_thread;
142 param.stack_base = new_thread->attr.stackaddr_attr;
143 param.stack_size = new_thread->attr.stacksize_attr;
144 param.tls_base = (char *)new_thread->tcb;
145 param.tls_size = sizeof(struct tcb);
146 param.child_tid = &new_thread->tid;
147 param.parent_tid = &new_thread->tid;
148 param.flags = 0;
149 if (new_thread->attr.flags & PTHREAD_SCOPE_SYSTEM)
150 param.flags |= THR_SYSTEM_SCOPE;
151 if (new_thread->attr.sched_inherit == PTHREAD_INHERIT_SCHED)
152 param.rtp = NULL;
153 else {
154 sched_param.sched_priority = new_thread->attr.prio;
155 _schedparam_to_rtp(new_thread->attr.sched_policy,
156 &sched_param, &rtp);
157 param.rtp = &rtp;
158 }
159
160 /* Schedule the new thread. */
161 if (create_suspended) {
162 SIGFILLSET(set);
163 SIGDELSET(set, SIGTRAP);
164 __sys_sigprocmask(SIG_SETMASK, &set, &oset);
165 new_thread->sigmask = oset;
166 SIGDELSET(new_thread->sigmask, SIGCANCEL);
167 }
168
169 ret = thr_new(&param, sizeof(param));
170
171 if (ret != 0) {
172 ret = errno;
173 /*
174 * Translate EPROCLIM into well-known POSIX code EAGAIN.
175 */
176 if (ret == EPROCLIM)
177 ret = EAGAIN;
178 }
179
180 if (create_suspended)
181 __sys_sigprocmask(SIG_SETMASK, &oset, NULL);
182
183 if (ret != 0) {
184 if (!locked)
185 THR_THREAD_LOCK(curthread, new_thread);
186 new_thread->state = PS_DEAD;
187 new_thread->tid = TID_TERMINATED;
188 if (new_thread->flags & THR_FLAGS_NEED_SUSPEND) {
189 new_thread->cycle++;
190 _thr_umtx_wake(&new_thread->cycle, INT_MAX, 0);
191 }
192 THR_THREAD_UNLOCK(curthread, new_thread);
193 THREAD_LIST_LOCK(curthread);
194 _thread_active_threads--;
195 new_thread->tlflags |= TLFLAGS_DETACHED;
196 _thr_ref_delete_unlocked(curthread, new_thread);
197 THREAD_LIST_UNLOCK(curthread);
198 } else if (locked) {
199 if (cpusetp != NULL) {
200 if (cpuset_setaffinity(CPU_LEVEL_WHICH, CPU_WHICH_TID,
201 TID(new_thread), cpusetsize, cpusetp)) {
202 ret = errno;
203 /* kill the new thread */
204 new_thread->force_exit = 1;
205 THR_THREAD_UNLOCK(curthread, new_thread);
206 goto out;
207 }
208 }
209
210 _thr_report_creation(curthread, new_thread);
211 THR_THREAD_UNLOCK(curthread, new_thread);
212out:
213 if (ret) {
214 THREAD_LIST_LOCK(curthread);
215 new_thread->tlflags |= TLFLAGS_DETACHED;
216 THR_GCLIST_ADD(new_thread);
217 THREAD_LIST_UNLOCK(curthread);
218 }
219 }
220
221 if (ret)
222 (*thread) = 0;
223 return (ret);
224}
225
226static int
227create_stack(struct pthread_attr *pattr)
228{
229 int ret;
230
231 /* Check if a stack was specified in the thread attributes: */
232 if ((pattr->stackaddr_attr) != NULL) {
233 pattr->guardsize_attr = 0;
234 pattr->flags |= THR_STACK_USER;
235 ret = 0;
236 }
237 else
238 ret = _thr_stack_alloc(pattr);
239 return (ret);
240}
241
242static void
243thread_start(struct pthread *curthread)
244{
245 sigset_t set;
246
247 if (curthread->attr.suspend == THR_CREATE_SUSPENDED)
248 set = curthread->sigmask;
249
250 /*
251 * This is used as a serialization point to allow parent
252 * to report 'new thread' event to debugger or tweak new thread's
253 * attributes before the new thread does real-world work.
254 */
255 THR_LOCK(curthread);
256 THR_UNLOCK(curthread);
257
258 if (curthread->force_exit)
259 _pthread_exit(PTHREAD_CANCELED);
260
261 if (curthread->attr.suspend == THR_CREATE_SUSPENDED) {
262#if 0
263 /* Done in THR_UNLOCK() */
264 _thr_ast(curthread);
265#endif
266
267 /*
268 * Parent thread have stored signal mask for us,
269 * we should restore it now.
270 */
271 __sys_sigprocmask(SIG_SETMASK, &set, NULL);
272 }
273
274 /* Run the current thread's start routine with argument: */
275 _pthread_exit(curthread->start_routine(curthread->arg));
276
277 /* This point should never be reached. */
278 PANIC("Thread has resumed after exit");
279}