sched: RT-balance, add new methods to sched_class

Dmitry Adamushko found that the current implementation of the RT
balancing code left out changes to the sched_setscheduler and
rt_mutex_setprio.

This patch addresses this issue by adding methods to the schedule classes
to handle being switched out of (switched_from) and being switched into
(switched_to) a sched_class. Also a method for changing of priorities
is also added (prio_changed).

This patch also removes some duplicate logic between rt_mutex_setprio and
sched_setscheduler.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Steven Rostedt 2008-01-25 21:08:22 +01:00 committed by Ingo Molnar
parent 9a897c5a67
commit cb46984504
5 changed files with 186 additions and 22 deletions

View file

@ -1152,6 +1152,18 @@ static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
#endif
}
static inline void check_class_changed(struct rq *rq, struct task_struct *p,
const struct sched_class *prev_class,
int oldprio, int running)
{
if (prev_class != p->sched_class) {
if (prev_class->switched_from)
prev_class->switched_from(rq, p, running);
p->sched_class->switched_to(rq, p, running);
} else
p->sched_class->prio_changed(rq, p, oldprio, running);
}
#ifdef CONFIG_SMP
/*
@ -4017,6 +4029,7 @@ void rt_mutex_setprio(struct task_struct *p, int prio)
unsigned long flags;
int oldprio, on_rq, running;
struct rq *rq;
const struct sched_class *prev_class = p->sched_class;
BUG_ON(prio < 0 || prio > MAX_PRIO);
@ -4042,18 +4055,10 @@ void rt_mutex_setprio(struct task_struct *p, int prio)
if (on_rq) {
if (running)
p->sched_class->set_curr_task(rq);
enqueue_task(rq, p, 0);
/*
* Reschedule if we are currently running on this runqueue and
* our priority decreased, or if we are not currently running on
* this runqueue and our priority is higher than the current's
*/
if (running) {
if (p->prio > oldprio)
resched_task(rq->curr);
} else {
check_preempt_curr(rq, p);
}
check_class_changed(rq, p, prev_class, oldprio, running);
}
task_rq_unlock(rq, &flags);
}
@ -4253,6 +4258,7 @@ int sched_setscheduler(struct task_struct *p, int policy,
{
int retval, oldprio, oldpolicy = -1, on_rq, running;
unsigned long flags;
const struct sched_class *prev_class = p->sched_class;
struct rq *rq;
/* may grab non-irq protected spin_locks */
@ -4346,18 +4352,10 @@ recheck:
if (on_rq) {
if (running)
p->sched_class->set_curr_task(rq);
activate_task(rq, p, 0);
/*
* Reschedule if we are currently running on this runqueue and
* our priority decreased, or if we are not currently running on
* this runqueue and our priority is higher than the current's
*/
if (running) {
if (p->prio > oldprio)
resched_task(rq->curr);
} else {
check_preempt_curr(rq, p);
}
check_class_changed(rq, p, prev_class, oldprio, running);
}
__task_rq_unlock(rq);
spin_unlock_irqrestore(&p->pi_lock, flags);