freebsd-nq/lib/libpthread/thread/thr_setschedparam.c
Daniel Eischen a0240e2cb0 Revamp libpthread so that it has a chance of working in an SMP
environment.  This includes support for multiple KSEs and KSEGs.

The ability to create more than 1 KSE via pthread_setconcurrency()
is in the works as well as support for PTHREAD_SCOPE_SYSTEM threads.
Those should come shortly.

There are still some known issues which davidxu and I are working
on, but it'll make it easier for us by committing what we have.

This library now passes all of the ACE tests that libc_r passes
with the exception of one.  It also seems to work OK with KDE
including konqueror, kwrite, etc.  I haven't been able to get
mozilla to run due to lack of java plugin, so I'd be interested
to see how it works with that.

Reviewed by:	davidxu
2003-04-18 05:04:16 +00:00

130 lines
4.3 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 "thr_private.h"
__weak_reference(_pthread_setschedparam, pthread_setschedparam);
int
_pthread_setschedparam(pthread_t pthread, int policy,
const struct sched_param *param)
{
struct pthread *curthread = _get_curthread();
int in_syncq;
int in_readyq = 0;
int old_prio;
int ret = 0;
if ((param == NULL) || (policy < SCHED_FIFO) || (policy > SCHED_RR)) {
/* Return an invalid argument error: */
ret = EINVAL;
} else if ((param->sched_priority < THR_MIN_PRIORITY) ||
(param->sched_priority > THR_MAX_PRIORITY)) {
/* Return an unsupported value error. */
ret = ENOTSUP;
/* Find the thread in the list of active threads: */
} else if ((ret = _thr_ref_add(curthread, pthread, /*include dead*/0))
== 0) {
/*
* Lock the threads scheduling queue while we change
* its priority:
*/
THR_SCHED_LOCK(curthread, pthread);
in_syncq = pthread->flags & THR_FLAGS_IN_SYNCQ;
/* Set the scheduling policy: */
pthread->attr.sched_policy = policy;
if (param->sched_priority ==
THR_BASE_PRIORITY(pthread->base_priority))
/*
* There is nothing to do; unlock the threads
* scheduling queue.
*/
THR_SCHED_UNLOCK(curthread, pthread);
else {
/*
* Remove the thread from its current priority
* queue before any adjustments are made to its
* active priority:
*/
old_prio = pthread->active_priority;
if ((pthread->flags & THR_FLAGS_IN_RUNQ) != 0) {
in_readyq = 1;
THR_RUNQ_REMOVE(pthread);
}
/* Set the thread base priority: */
pthread->base_priority &=
(THR_SIGNAL_PRIORITY | THR_RT_PRIORITY);
pthread->base_priority = param->sched_priority;
/* Recalculate the active priority: */
pthread->active_priority = MAX(pthread->base_priority,
pthread->inherited_priority);
if (in_readyq) {
if ((pthread->priority_mutex_count > 0) &&
(old_prio > pthread->active_priority)) {
/*
* POSIX states that if the priority is
* being lowered, the thread must be
* inserted at the head of the queue for
* its priority if it owns any priority
* protection or inheritence mutexes.
*/
THR_RUNQ_INSERT_HEAD(pthread);
}
else
THR_RUNQ_INSERT_TAIL(pthread);
}
/* Unlock the threads scheduling queue: */
THR_SCHED_UNLOCK(curthread, pthread);
/*
* Check for any mutex priority adjustments. This
* includes checking for a priority mutex on which
* this thread is waiting.
*/
_mutex_notify_priochange(curthread, pthread, in_syncq);
}
_thr_ref_delete(curthread, pthread);
}
return (ret);
}