freebsd-skq/lib/libthr/thread/thr_setschedparam.c
David Xu a091d823ad Import my recent 1:1 threading working. some features improved includes:
1. fast simple type mutex.
 2. __thread tls works.
 3. asynchronous cancellation works ( using signal ).
 4. thread synchronization is fully based on umtx, mainly, condition
    variable and other synchronization objects were rewritten by using
    umtx directly. those objects can be shared between processes via
    shared memory, it has to change ABI which does not happen yet.
 5. default stack size is increased to 1M on 32 bits platform, 2M for
    64 bits platform.
As the result, some mysql super-smack benchmarks show performance is
improved massivly.

Okayed by: jeff, mtm, rwatson, scottl
2005-04-02 01:20:00 +00:00

137 lines
4.5 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_THREAD_LOCK(curthread, pthread);
if (pthread->state == PS_DEAD) {
THR_THREAD_UNLOCK(curthread, pthread);
_thr_ref_delete(curthread, pthread);
return (ESRCH);
}
in_syncq = pthread->sflags & 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_THREAD_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_THREAD_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);
}