24912a0c07
o In the rwlock code: move a duplicated check inside an if..else to after the if...else clause. o When initializing a static rwlock move the initialization check inside the lock. o In thr_setschedparam.c: When breaking out of the trylock...retry if busy loop make sure to reset the mtx pointer to null if the mutex is nolonger in a queue.
124 lines
4.1 KiB
C
124 lines
4.1 KiB
C
/*
|
|
* Copyright (c) 1998 Daniel Eischen <eischen@vigrid.com>.
|
|
* 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 Daniel Eischen.
|
|
* 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 DANIEL EISCHEN 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 <sys/param.h>
|
|
#include <pthread.h>
|
|
#include <stdlib.h>
|
|
#include "thr_private.h"
|
|
|
|
__weak_reference(_pthread_getschedparam, pthread_getschedparam);
|
|
__weak_reference(_pthread_setschedparam, pthread_setschedparam);
|
|
|
|
int
|
|
_pthread_getschedparam(pthread_t pthread, int *policy,
|
|
struct sched_param *param)
|
|
{
|
|
if (param == NULL || policy == NULL)
|
|
return (EINVAL);
|
|
if (_find_thread(pthread) == ESRCH)
|
|
return (ESRCH);
|
|
param->sched_priority = pthread->base_priority;
|
|
*policy = pthread->attr.sched_policy;
|
|
return(0);
|
|
}
|
|
|
|
int
|
|
_pthread_setschedparam(pthread_t pthread, int policy,
|
|
const struct sched_param *param)
|
|
{
|
|
struct pthread_mutex *mtx;
|
|
int old_prio;
|
|
|
|
mtx = NULL;
|
|
old_prio = 0;
|
|
if ((param == NULL) || (policy < SCHED_FIFO) || (policy > SCHED_RR))
|
|
return (EINVAL);
|
|
if ((param->sched_priority < PTHREAD_MIN_PRIORITY) ||
|
|
(param->sched_priority > PTHREAD_MAX_PRIORITY))
|
|
return (ENOTSUP);
|
|
if (_find_thread(pthread) != 0)
|
|
return (ESRCH);
|
|
|
|
/*
|
|
* If the pthread is waiting on a mutex grab it now. Doing it now
|
|
* even though we do not need it immediately greatly simplifies the
|
|
* LOR avoidance code.
|
|
*/
|
|
do {
|
|
PTHREAD_LOCK(pthread);
|
|
if ((pthread->flags & PTHREAD_FLAGS_IN_MUTEXQ) != 0) {
|
|
mtx = pthread->data.mutex;
|
|
if (_spintrylock(&mtx->lock) == EBUSY)
|
|
PTHREAD_UNLOCK(pthread);
|
|
else
|
|
break;
|
|
} else {
|
|
mtx = NULL;
|
|
break;
|
|
}
|
|
} while (1);
|
|
|
|
PTHREAD_ASSERT(pthread->active_priority >= pthread->inherited_priority,
|
|
"active priority cannot be less than inherited priority");
|
|
old_prio = pthread->base_priority;
|
|
pthread->base_priority = param->sched_priority;
|
|
if (param->sched_priority <= pthread->active_priority) {
|
|
/*
|
|
* Active priority is affected only if it was the
|
|
* base priority and the new base priority is lower.
|
|
*/
|
|
if (pthread->active_priority == old_prio &&
|
|
pthread->active_priority != pthread->inherited_priority) {
|
|
pthread->active_priority = param->sched_priority;
|
|
readjust_priorities(pthread, mtx);
|
|
}
|
|
|
|
} else {
|
|
/*
|
|
* New base priority is greater than active priority. This
|
|
* only affects threads that are holding priority inheritance
|
|
* mutexes this thread is waiting on and its position in the
|
|
* queue.
|
|
*/
|
|
pthread->active_priority = param->sched_priority;
|
|
readjust_priorities(pthread, mtx);
|
|
|
|
}
|
|
pthread->attr.sched_policy = policy;
|
|
PTHREAD_UNLOCK(pthread);
|
|
if (mtx != NULL)
|
|
_SPINUNLOCK(&mtx->lock);
|
|
return(0);
|
|
}
|