/*
* Must be called with nklock locked, interrupts off. Thread may be
* blocked.
*/
void xnsched_migrate_passive(struct xnthread *thread, struct xnsched *sched)
{
migrate_thread(thread, sched);
if (!xnthread_test_state(thread, XNTHREAD_BLOCK_BITS)) {
xnsched_requeue(thread);
xnthread_set_state(thread, XNREADY);
}
}
/* Must be called with nklock locked, interrupts off. */
struct xnthread *xnsched_pick_next(struct xnsched *sched)
{
struct xnthread *curr = sched->curr;
struct xnsched_class *p;
struct xnthread *thread;
if (!xnthread_test_state(curr, XNTHREAD_BLOCK_BITS | XNZOMBIE)) {
/*
* Do not preempt the current thread if it holds the
* scheduler lock.
*/
if (xnthread_test_state(curr, XNLOCK)) {
xnsched_set_self_resched(sched);
return curr;
}
/*
* Push the current thread back to the runnable queue
* of the scheduling class it belongs to, if not yet
* linked to it (XNREADY tells us if it is).
*/
if (!xnthread_test_state(curr, XNREADY)) {
xnsched_requeue(curr);
xnthread_set_state(curr, XNREADY);
}
#ifdef __XENO_SIM__
if (nkpod->schedhook)
nkpod->schedhook(curr, XNREADY);
#endif /* __XENO_SIM__ */
}
/*
* Find the runnable thread having the highest priority among
* all scheduling classes, scanned by decreasing priority.
*/
#ifdef CONFIG_XENO_OPT_SCHED_CLASSES
for_each_xnsched_class(p) {
thread = p->sched_pick(sched);
if (thread) {
xnthread_clear_state(thread, XNREADY);
return thread;
}
}
return NULL; /* Never executed because of the idle class. */
#else /* !CONFIG_XENO_OPT_SCHED_CLASSES */
thread = __xnsched_rt_pick(sched); (void)p;
if (unlikely(thread == NULL))
thread = &sched->rootcb;
xnthread_clear_state(thread, XNREADY);
return thread;
#endif /* CONFIG_XENO_OPT_SCHED_CLASSES */
}
/* Must be called with nklock locked, interrupts off. thread may be
* blocked. */
void xnsched_migrate_passive(struct xnthread *thread, struct xnsched *sched)
{
struct xnsched_class *sched_class = thread->sched_class;
if (xnthread_test_state(thread, XNREADY)) {
xnsched_dequeue(thread);
xnthread_clear_state(thread, XNREADY);
}
if (sched_class->sched_migrate)
sched_class->sched_migrate(thread, sched);
/*
* WARNING: the scheduling class may have just changed as a
* result of calling the per-class migration hook.
*/
xnsched_set_resched(thread->sched);
thread->sched = sched;
if (!xnthread_test_state(thread, XNTHREAD_BLOCK_BITS)) {
xnsched_requeue(thread);
xnthread_set_state(thread, XNREADY);
}
}
