freebsd-dev/lib/libpthread/thread/thr_yield.c
2007-01-12 07:26:21 +00:00

76 lines
2.5 KiB
C

/*
* Copyright (c) 1995 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. 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 <pthread.h>
#include "thr_private.h"
LT10_COMPAT_PRIVATE(_sched_yield);
LT10_COMPAT_DEFAULT(sched_yield);
LT10_COMPAT_PRIVATE(_pthread_yield);
LT10_COMPAT_DEFAULT(pthread_yield);
__weak_reference(_sched_yield, sched_yield);
__weak_reference(_pthread_yield, pthread_yield);
int
_sched_yield(void)
{
struct pthread *curthread = _get_curthread();
if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM)
return (__sys_sched_yield());
/* Reset the accumulated time slice value for the current thread: */
curthread->slice_usec = -1;
/* Schedule the next thread: */
_thr_sched_switch(curthread);
/* Always return no error. */
return(0);
}
/* Draft 4 yield */
void
_pthread_yield(void)
{
struct pthread *curthread = _get_curthread();
if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM) {
__sys_sched_yield();
return;
}
/* Reset the accumulated time slice value for the current thread: */
curthread->slice_usec = -1;
/* Schedule the next thread: */
_thr_sched_switch(curthread);
}