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/*
* Copyright (c) 2003 Daniel M. Eischen <deischen@gdeb.com>
* Copyright (c) 1995-1998 John Birrell <jb@cimlogic.com.au>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by John Birrell.
* 4. Neither the name of the author nor the names of any co-contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <stddef.h>
#include <pthread.h>
#include <sys/signalvar.h>
#include "thr_private.h"
static void free_thread(struct pthread *curthread, struct pthread *thread);
static int create_stack(struct pthread_attr *pattr);
static void free_stack(struct pthread *curthread, struct pthread_attr *pattr);
static void thread_start(struct pthread *curthread);
__weak_reference(_pthread_create, pthread_create);
int
_pthread_create(pthread_t * thread, const pthread_attr_t * attr,
void *(*start_routine) (void *), void *arg)
{
ucontext_t uc;
sigset_t sigmask, oldsigmask;
struct pthread *curthread, *new_thread;
int ret = 0, locked;
_thr_check_init();
/*
* Tell libc and others now they need lock to protect their data.
*/
if (_thr_isthreaded() == 0 && _thr_setthreaded(1))
return (EAGAIN);
curthread = _get_curthread();
if ((new_thread = _thr_alloc(curthread)) == NULL)
return (EAGAIN);
if (attr == NULL || *attr == NULL)
/* Use the default thread attributes: */
new_thread->attr = _pthread_attr_default;
else
new_thread->attr = *(*attr);
if (new_thread->attr.sched_inherit == PTHREAD_INHERIT_SCHED) {
/* inherit scheduling contention scope */
if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM)
new_thread->attr.flags |= PTHREAD_SCOPE_SYSTEM;
else
new_thread->attr.flags &= ~PTHREAD_SCOPE_SYSTEM;
/*
* scheduling policy and scheduling parameters will be
* inherited in following code.
*/
}
if (_thr_scope_system > 0)
new_thread->attr.flags |= PTHREAD_SCOPE_SYSTEM;
else if (_thr_scope_system < 0)
new_thread->attr.flags &= ~PTHREAD_SCOPE_SYSTEM;
new_thread->tid = TID_TERMINATED;
if (create_stack(&new_thread->attr) != 0) {
/* Insufficient memory to create a stack: */
_thr_free(curthread, new_thread);
return (EAGAIN);
}
/*
* Write a magic value to the thread structure
* to help identify valid ones:
*/
new_thread->magic = THR_MAGIC;
new_thread->start_routine = start_routine;
new_thread->arg = arg;
new_thread->cancelflags = PTHREAD_CANCEL_ENABLE |
PTHREAD_CANCEL_DEFERRED;
getcontext(&uc);
SIGFILLSET(uc.uc_sigmask);
uc.uc_stack.ss_sp = new_thread->attr.stackaddr_attr;
uc.uc_stack.ss_size = new_thread->attr.stacksize_attr;
makecontext(&uc, (void (*)(void))thread_start, 1, new_thread);
/*
* Check if this thread is to inherit the scheduling
* attributes from its parent:
*/
if (new_thread->attr.sched_inherit == PTHREAD_INHERIT_SCHED) {
/*
* Copy the scheduling attributes. Lock the scheduling
* lock to get consistent scheduling parameters.
*/
THR_LOCK(curthread);
new_thread->base_priority = curthread->base_priority;
new_thread->attr.prio = curthread->base_priority;
new_thread->attr.sched_policy = curthread->attr.sched_policy;
THR_UNLOCK(curthread);
} else {
/*
* Use just the thread priority, leaving the
* other scheduling attributes as their
* default values:
*/
new_thread->base_priority = new_thread->attr.prio;
}
new_thread->active_priority = new_thread->base_priority;
/* Initialize the mutex queue: */
TAILQ_INIT(&new_thread->mutexq);
TAILQ_INIT(&new_thread->pri_mutexq);
/* Initialise hooks in the thread structure: */
if (new_thread->attr.suspend == THR_CREATE_SUSPENDED)
new_thread->flags = THR_FLAGS_SUSPENDED;
new_thread->state = PS_RUNNING;
/*
* Thread created by thr_create() inherits currrent thread
* sigmask, however, before new thread setup itself correctly,
* it can not handle signal, so we should masks all signals here.
*/
SIGFILLSET(sigmask);
SIGDELSET(sigmask, SIGTRAP);
__sys_sigprocmask(SIG_SETMASK, &sigmask, &oldsigmask);
new_thread->sigmask = oldsigmask;
/* Add the new thread. */
_thr_link(curthread, new_thread);
/* Return thread pointer eariler so that new thread can use it. */
(*thread) = new_thread;
if (SHOULD_REPORT_EVENT(curthread, TD_CREATE)) {
THR_THREAD_LOCK(curthread, new_thread);
locked = 1;
} else
locked = 0;
/* Schedule the new thread. */
ret = thr_create(&uc, &new_thread->tid, 0);
__sys_sigprocmask(SIG_SETMASK, &oldsigmask, NULL);
if (ret != 0) {
if (locked)
THR_THREAD_UNLOCK(curthread, new_thread);
_thr_unlink(curthread, new_thread);
free_thread(curthread, new_thread);
(*thread) = 0;
ret = EAGAIN;
} else if (locked) {
_thr_report_creation(curthread, new_thread);
THR_THREAD_UNLOCK(curthread, new_thread);
}
return (ret);
}
static void
free_thread(struct pthread *curthread, struct pthread *thread)
{
free_stack(curthread, &thread->attr);
curthread->tid = TID_TERMINATED;
_thr_free(curthread, thread);
}
static int
create_stack(struct pthread_attr *pattr)
{
int ret;
/* Check if a stack was specified in the thread attributes: */
if ((pattr->stackaddr_attr) != NULL) {
pattr->guardsize_attr = 0;
pattr->flags |= THR_STACK_USER;
ret = 0;
}
else
ret = _thr_stack_alloc(pattr);
return (ret);
}
static void
free_stack(struct pthread *curthread, struct pthread_attr *pattr)
{
if ((pattr->flags & THR_STACK_USER) == 0) {
THREAD_LIST_LOCK(curthread);
/* Stack routines don't use malloc/free. */
_thr_stack_free(pattr);
THREAD_LIST_UNLOCK(curthread);
}
}
static void
thread_start(struct pthread *curthread)
{
_tcb_set(curthread->tcb);
/* Thread was created with all signals blocked, unblock them. */
__sys_sigprocmask(SIG_SETMASK, &curthread->sigmask, NULL);
if (curthread->flags & THR_FLAGS_NEED_SUSPEND)
_thr_suspend_check(curthread);
THR_LOCK(curthread);
THR_UNLOCK(curthread);
/* Run the current thread's start routine with argument: */
pthread_exit(curthread->start_routine(curthread->arg));
/* This point should never be reached. */
PANIC("Thread has resumed after exit");
}
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