Commit 4cbb6214 authored by Ingo Molnar's avatar Ingo Molnar
Browse files

Merge branch 'tip/sched/core' of... 

Merge branch 'tip/sched/core' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

 into sched/core

Pull a scheduler optimization commit from Steven Rostedt.

Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parents 668ce0ac 8d3d5ada

kernel/sched/rt.c

+26 −30
Original line number Diff line number Diff line
@@ -1803,45 +1803,41 @@ static void task_woken_rt(struct rq *rq, struct task_struct *p) 
static void set_cpus_allowed_rt(struct task_struct *p,

				const struct cpumask *new_mask)

{

	int weight = cpumask_weight(new_mask);

	struct rq *rq;

	int weight;



	BUG_ON(!rt_task(p));



	/*

	 * Update the migration status of the RQ if we have an RT task

	 * which is running AND changing its weight value.

	 */

	if (p->on_rq && (weight != p->rt.nr_cpus_allowed)) {

		struct rq *rq = task_rq(p);

	if (!p->on_rq)

		return;



		if (!task_current(rq, p)) {

			/*

			 * Make sure we dequeue this task from the pushable list

			 * before going further.  It will either remain off of

			 * the list because we are no longer pushable, or it

			 * will be requeued.

			 */

			if (p->rt.nr_cpus_allowed > 1)

				dequeue_pushable_task(rq, p);

	weight = cpumask_weight(new_mask);



	/*

			 * Requeue if our weight is changing and still > 1

	 * Only update if the process changes its state from whether it

	 * can migrate or not.

	 */

			if (weight > 1)

				enqueue_pushable_task(rq, p);

	if ((p->rt.nr_cpus_allowed > 1) == (weight > 1))

		return;



		}

	rq = task_rq(p);



		if ((p->rt.nr_cpus_allowed <= 1) && (weight > 1)) {

			rq->rt.rt_nr_migratory++;

		} else if ((p->rt.nr_cpus_allowed > 1) && (weight <= 1)) {

	/*

	 * The process used to be able to migrate OR it can now migrate

	 */

	if (weight <= 1) {

		if (!task_current(rq, p))

			dequeue_pushable_task(rq, p);

		BUG_ON(!rq->rt.rt_nr_migratory);

		rq->rt.rt_nr_migratory--;

	} else {

		if (!task_current(rq, p))

			enqueue_pushable_task(rq, p);

		rq->rt.rt_nr_migratory++;

	}



	update_rt_migration(&rq->rt);

}

}



/* Assumes rq->lock is held */

static void rq_online_rt(struct rq *rq)