/* Must be called with nklock locked, interrupts off. */
void xnsched_track_policy(struct xnthread *thread,
struct xnthread *target)
{
union xnsched_policy_param param;
if (xnthread_test_state(thread, XNREADY))
xnsched_dequeue(thread);
/*
* Self-targeting means to reset the scheduling policy and
* parameters to the base ones. Otherwise, make thread inherit
* the scheduling data from target.
*/
if (target == thread) {
thread->sched_class = thread->base_class;
xnsched_trackprio(thread, NULL);
} else {
xnsched_getparam(target, ¶m);
thread->sched_class = target->sched_class;
xnsched_trackprio(thread, ¶m);
}
if (xnthread_test_state(thread, XNREADY))
xnsched_enqueue(thread);
xnsched_set_resched(thread->sched);
}
/* Must be called with nklock locked, interrupts off. */
void xnsched_putback(struct xnthread *thread)
{
if (xnthread_test_state(thread, XNREADY))
xnsched_dequeue(thread);
else
xnthread_set_state(thread, XNREADY);
xnsched_enqueue(thread);
xnsched_set_resched(thread->sched);
}
/* Must be called with nklock locked, interrupts off. */
int xnsched_set_policy(struct xnthread *thread,
struct xnsched_class *sched_class,
const union xnsched_policy_param *p)
{
int ret;
/*
* Declaring a thread to a new scheduling class may fail, so
* we do that early, while the thread is still a member of the
* previous class. However, this also means that the
* declaration callback shall not do anything that might
* affect the previous class (such as touching thread->rlink
* for instance).
*/
if (sched_class != thread->base_class) {
if (sched_class->sched_declare) {
ret = sched_class->sched_declare(thread, p);
if (ret)
return ret;
}
sched_class->nthreads++;
}
/*
* As a special case, we may be called from xnthread_init()
* with no previous scheduling class at all.
*/
if (likely(thread->base_class != NULL)) {
if (xnthread_test_state(thread, XNREADY))
xnsched_dequeue(thread);
if (sched_class != thread->base_class)
xnsched_forget(thread);
}
thread->sched_class = sched_class;
thread->base_class = sched_class;
xnsched_setparam(thread, p);
thread->bprio = thread->cprio;
if (xnthread_test_state(thread, XNREADY))
xnsched_enqueue(thread);
if (xnthread_test_state(thread, XNSTARTED))
xnsched_set_resched(thread->sched);
return 0;
}
