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/*
* 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 <fcntl.h>
#include <unistd.h>
#include <stddef.h>
#include <sys/time.h>
#include <machine/reg.h>
#include <pthread.h>
#include "thr_private.h"
#include "libc_private.h"
static u_int64_t next_uniqueid = 1;
#define OFF(f) offsetof(struct pthread, f)
int _thread_next_offset = OFF(tle.tqe_next);
int _thread_uniqueid_offset = OFF(uniqueid);
int _thread_state_offset = OFF(state);
int _thread_name_offset = OFF(name);
int _thread_ctx_offset = OFF(ctx);
#undef OFF
int _thread_PS_RUNNING_value = PS_RUNNING;
int _thread_PS_DEAD_value = PS_DEAD;
__weak_reference(_pthread_create, pthread_create);
int
_pthread_create(pthread_t * thread, const pthread_attr_t * attr,
void *(*start_routine) (void *), void *arg)
{
int f_gc = 0;
int ret = 0;
pthread_t gc_thread;
pthread_t new_thread;
pthread_attr_t pattr;
int flags;
void *stack;
/*
* Locking functions in libc are required when there are
* threads other than the initial thread.
*/
__isthreaded = 1;
/* Allocate memory for the thread structure: */
if ((new_thread = (pthread_t) malloc(sizeof(struct pthread))) == NULL)
return (EAGAIN);
/* Check if default thread attributes are required: */
if (attr == NULL || *attr == NULL)
pattr = &pthread_attr_default;
else
pattr = *attr;
/* Check if a stack was specified in the thread attributes: */
if ((stack = pattr->stackaddr_attr) == NULL) {
stack = _thread_stack_alloc(pattr->stacksize_attr,
pattr->guardsize_attr);
if (stack == NULL) {
free(new_thread);
return (EAGAIN);
}
}
/* Initialise the thread structure: */
memset(new_thread, 0, sizeof(struct pthread));
new_thread->stack = stack;
new_thread->start_routine = start_routine;
new_thread->arg = arg;
new_thread->cancelflags = PTHREAD_CANCEL_ENABLE |
PTHREAD_CANCEL_DEFERRED;
/*
* Write a magic value to the thread structure
* to help identify valid ones:
*/
new_thread->magic = PTHREAD_MAGIC;
/* Initialise the machine context: */
getcontext(&new_thread->ctx);
new_thread->ctx.uc_stack.ss_sp = new_thread->stack;
new_thread->ctx.uc_stack.ss_size = pattr->stacksize_attr;
makecontext(&new_thread->ctx, _thread_start, 0);
new_thread->arch_id = _set_curthread(&new_thread->ctx, new_thread, &ret);
if (ret != 0) {
if (pattr->stackaddr_attr == NULL) {
STACK_LOCK;
_thread_stack_free(new_thread->stack,
pattr->stacksize_attr, pattr->guardsize_attr);
STACK_UNLOCK;
}
free(new_thread);
return (ret);
}
/* Copy the thread attributes: */
memcpy(&new_thread->attr, pattr, sizeof(struct pthread_attr));
/*
* Check if this thread is to inherit the scheduling
* attributes from its parent:
*/
if (new_thread->attr.flags & PTHREAD_INHERIT_SCHED) {
/* Copy the scheduling attributes: */
new_thread->base_priority = curthread->base_priority &
~PTHREAD_SIGNAL_PRIORITY;
new_thread->attr.prio = curthread->base_priority &
~PTHREAD_SIGNAL_PRIORITY;
new_thread->attr.sched_policy = curthread->attr.sched_policy;
} 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;
new_thread->inherited_priority = 0;
/* Initialize joiner to NULL (no joiner): */
new_thread->joiner = NULL;
/* Initialize the mutex queue: */
TAILQ_INIT(&new_thread->mutexq);
/* Initialise hooks in the thread structure: */
new_thread->specific = NULL;
new_thread->cleanup = NULL;
new_thread->flags = 0;
/*
* Initialise the unique id which GDB uses to
* track threads.
*/
new_thread->uniqueid = next_uniqueid++;
THREAD_LIST_LOCK;
/*
* Check if the garbage collector thread
* needs to be started.
*/
f_gc = (TAILQ_FIRST(&_thread_list) == _thread_initial);
/* Add the thread to the linked list of all threads: */
TAILQ_INSERT_HEAD(&_thread_list, new_thread, tle);
/*
* Create the thread.
*
*/
if (pattr->suspend == PTHREAD_FLAGS_SUSPENDED)
flags = THR_SUSPENDED;
else
flags = 0;
ret = thr_create(&new_thread->ctx, &new_thread->thr_id, flags);
if (ret != 0) {
_thread_printf(STDERR_FILENO, "thr_create() == %d\n", ret);
PANIC("thr_create");
}
THREAD_LIST_UNLOCK;
/* Return a pointer to the thread structure: */
(*thread) = new_thread;
/*
* Start a garbage collector thread
* if necessary.
*/
if (f_gc && pthread_create(&gc_thread,NULL, _thread_gc,NULL) != 0)
PANIC("Can't create gc thread");
return (0);
}
void
_thread_start(void)
{
/* 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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