int
_pthread_getschedparam(pthread_t pthread, int *policy,
struct sched_param *param)
{
struct pthread *curthread = _get_curthread();
int ret, tmp;
if ((param == NULL) || (policy == NULL))
/* Return an invalid argument error: */
ret = EINVAL;
else if (pthread == curthread) {
/*
* Avoid searching the thread list when it is the current
* thread.
*/
THR_SCHED_LOCK(curthread, curthread);
param->sched_priority =
THR_BASE_PRIORITY(pthread->base_priority);
tmp = pthread->attr.sched_policy;
THR_SCHED_UNLOCK(curthread, curthread);
*policy = tmp;
ret = 0;
}
/* Find the thread in the list of active threads. */
else if ((ret = _thr_ref_add(curthread, pthread, /*include dead*/0))
== 0) {
THR_SCHED_LOCK(curthread, pthread);
param->sched_priority =
THR_BASE_PRIORITY(pthread->base_priority);
tmp = pthread->attr.sched_policy;
THR_SCHED_UNLOCK(curthread, pthread);
_thr_ref_delete(curthread, pthread);
*policy = tmp;
}
return (ret);
}
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);
}
