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 178647 2008-04-29 03:58:18Z 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 if (curthread->in_sigcancel_handler)
131 new_thread->unblock_sigcancel = 1;
132 else
133 new_thread->unblock_sigcancel = 0;
134
135 /* Add the new thread. */
136 new_thread->refcount = 1;
137 _thr_link(curthread, new_thread);
138 /* Return thread pointer eariler so that new thread can use it. */
139 (*thread) = new_thread;
140 if (SHOULD_REPORT_EVENT(curthread, TD_CREATE) || cpusetp != NULL) {
141 THR_THREAD_LOCK(curthread, new_thread);
142 locked = 1;
143 } else
144 locked = 0;
145 param.start_func = (void (*)(void *)) thread_start;
146 param.arg = new_thread;
147 param.stack_base = new_thread->attr.stackaddr_attr;
148 param.stack_size = new_thread->attr.stacksize_attr;
149 param.tls_base = (char *)new_thread->tcb;
150 param.tls_size = sizeof(struct tcb);
151 param.child_tid = &new_thread->tid;
152 param.parent_tid = &new_thread->tid;
153 param.flags = 0;
154 if (new_thread->attr.flags & PTHREAD_SCOPE_SYSTEM)
155 param.flags |= THR_SYSTEM_SCOPE;
156 if (new_thread->attr.sched_inherit == PTHREAD_INHERIT_SCHED)
157 param.rtp = NULL;
158 else {
159 sched_param.sched_priority = new_thread->attr.prio;
160 _schedparam_to_rtp(new_thread->attr.sched_policy,
161 &sched_param, &rtp);
162 param.rtp = &rtp;
163 }
164
165 /* Schedule the new thread. */
166 if (create_suspended) {
167 SIGFILLSET(set);
168 SIGDELSET(set, SIGTRAP);
169 __sys_sigprocmask(SIG_SETMASK, &set, &oset);
170 new_thread->sigmask = oset;
171 SIGDELSET(new_thread->sigmask, SIGCANCEL);
172 }
173
174 ret = thr_new(&param, sizeof(param));
175
176 if (ret != 0) {
177 ret = errno;
178 /*
179 * Translate EPROCLIM into well-known POSIX code EAGAIN.
180 */
181 if (ret == EPROCLIM)
182 ret = EAGAIN;
183 }
184
185 if (create_suspended)
186 __sys_sigprocmask(SIG_SETMASK, &oset, NULL);
187
188 if (ret != 0) {
189 if (!locked)
190 THR_THREAD_LOCK(curthread, new_thread);
191 new_thread->state = PS_DEAD;
192 new_thread->tid = TID_TERMINATED;
193 if (new_thread->flags & THR_FLAGS_NEED_SUSPEND) {
194 new_thread->cycle++;
195 _thr_umtx_wake(&new_thread->cycle, INT_MAX, 0);
196 }
197 THR_THREAD_UNLOCK(curthread, new_thread);
198 THREAD_LIST_LOCK(curthread);
199 _thread_active_threads--;
200 new_thread->tlflags |= TLFLAGS_DETACHED;
201 _thr_ref_delete_unlocked(curthread, new_thread);
202 THREAD_LIST_UNLOCK(curthread);
203 } else if (locked) {
204 if (cpusetp != NULL) {
205 if (cpuset_setaffinity(CPU_LEVEL_WHICH, CPU_WHICH_TID,
206 TID(new_thread), cpusetsize, cpusetp)) {
207 ret = errno;
208 /* kill the new thread */
209 new_thread->force_exit = 1;
210 THR_THREAD_UNLOCK(curthread, new_thread);
211 goto out;
212 }
213 }
214
215 _thr_report_creation(curthread, new_thread);
216 THR_THREAD_UNLOCK(curthread, new_thread);
217out:
218 if (ret) {
219 THREAD_LIST_LOCK(curthread);
220 new_thread->tlflags |= TLFLAGS_DETACHED;
221 THR_GCLIST_ADD(new_thread);
222 THREAD_LIST_UNLOCK(curthread);
223 }
224 }
225
226 if (ret)
227 (*thread) = 0;
228 return (ret);
229}
230
231static int
232create_stack(struct pthread_attr *pattr)
233{
234 int ret;
235
236 /* Check if a stack was specified in the thread attributes: */
237 if ((pattr->stackaddr_attr) != NULL) {
238 pattr->guardsize_attr = 0;
239 pattr->flags |= THR_STACK_USER;
240 ret = 0;
241 }
242 else
243 ret = _thr_stack_alloc(pattr);
244 return (ret);
245}
246
247static void
248thread_start(struct pthread *curthread)
249{
250 sigset_t set;
251
252 if (curthread->attr.suspend == THR_CREATE_SUSPENDED)
253 set = curthread->sigmask;
254
255 /*
256 * This is used as a serialization point to allow parent
257 * to report 'new thread' event to debugger or tweak new thread's
258 * attributes before the new thread does real-world work.
259 */
260 THR_LOCK(curthread);
261 THR_UNLOCK(curthread);
262
263 if (curthread->force_exit)
264 _pthread_exit(PTHREAD_CANCELED);
265
266 if (curthread->unblock_sigcancel) {
267 sigset_t set1;
268
269 SIGEMPTYSET(set1);
270 SIGADDSET(set1, SIGCANCEL);
271 __sys_sigprocmask(SIG_UNBLOCK, &set1, NULL);
272 }
273
274 if (curthread->attr.suspend == THR_CREATE_SUSPENDED) {
275#if 0
276 /* Done in THR_UNLOCK() */
277 _thr_ast(curthread);
278#endif
279
280 /*
281 * Parent thread have stored signal mask for us,
282 * we should restore it now.
283 */
284 __sys_sigprocmask(SIG_SETMASK, &set, NULL);
285 }
286
287 /* Run the current thread's start routine with argument: */
288 _pthread_exit(curthread->start_routine(curthread->arg));
289
290 /* This point should never be reached. */
291 PANIC("Thread has resumed after exit");
292}