diff options
Diffstat (limited to 'lib/libpthread/thread/thr_setschedparam.c')
| -rw-r--r-- | lib/libpthread/thread/thr_setschedparam.c | 136 |
1 files changed, 136 insertions, 0 deletions
diff --git a/lib/libpthread/thread/thr_setschedparam.c b/lib/libpthread/thread/thr_setschedparam.c new file mode 100644 index 0000000..63cd073 --- /dev/null +++ b/lib/libpthread/thread/thr_setschedparam.c @@ -0,0 +1,136 @@ +/* + * 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); + if ((pthread->state == PS_DEAD) || + (pthread->state == PS_DEADLOCK) || + ((pthread->flags & THR_FLAGS_EXITING) != 0)) { + THR_SCHED_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_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); +} |
