Commit 3261ed0b authored by Byungchul Park's avatar Byungchul Park Committed by Ingo Molnar
Browse files

sched/deadline: Change return value of cpudl_find() 



cpudl_find() users are only interested in knowing if suitable CPU(s)
were found or not (and then they look at later_mask to know which).

Change cpudl_find() return type accordingly. Aligns with rt code.

Signed-off-by: default avatarByungchul Park <byungchul.park@lge.com>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: <bristot@redhat.com>
Cc: <juri.lelli@gmail.com>
Cc: <kernel-team@lge.com>
Cc: <rostedt@goodmis.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1495504859-10960-3-git-send-email-byungchul.park@lge.com


Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent b18c3ca1

kernel/sched/cpudeadline.c

+13 −13
Original line number Diff line number Diff line
@@ -119,29 +119,29 @@ static inline int cpudl_maximum(struct cpudl *cp) 
 * @p: the task

 * @later_mask: a mask to fill in with the selected CPUs (or NULL)

 *

 * Returns: int - best CPU (heap maximum if suitable)

 * Returns: int - CPUs were found

 */

int cpudl_find(struct cpudl *cp, struct task_struct *p,

	       struct cpumask *later_mask)

{

	int best_cpu = -1;

	const struct sched_dl_entity *dl_se = &p->dl;



	if (later_mask &&

	    cpumask_and(later_mask, cp->free_cpus, &p->cpus_allowed)) {

		best_cpu = cpumask_any(later_mask);

		goto out;

	} else if (cpumask_test_cpu(cpudl_maximum(cp), &p->cpus_allowed) &&

		return 1;

	} else {

		int best_cpu = cpudl_maximum(cp);

		WARN_ON(best_cpu != -1 && !cpu_present(best_cpu));



		if (cpumask_test_cpu(best_cpu, &p->cpus_allowed) &&

		    dl_time_before(dl_se->deadline, cp->elements[0].dl)) {

		best_cpu = cpudl_maximum(cp);

			if (later_mask)

				cpumask_set_cpu(best_cpu, later_mask);

	}



out:

	WARN_ON(best_cpu != -1 && !cpu_present(best_cpu));



	return best_cpu;

			return 1;

		}

	}

	return 0;

}



/*

kernel/sched/deadline.c

+3 −3
Original line number Diff line number Diff line
@@ -1594,7 +1594,7 @@ static void check_preempt_equal_dl(struct rq *rq, struct task_struct *p) 
	 * let's hope p can move out.

	 */

	if (rq->curr->nr_cpus_allowed == 1 ||

	    cpudl_find(&rq->rd->cpudl, rq->curr, NULL) == -1)

	    !cpudl_find(&rq->rd->cpudl, rq->curr, NULL))

		return;



	/*
@@ -1602,7 +1602,7 @@ static void check_preempt_equal_dl(struct rq *rq, struct task_struct *p) 
	 * see if it is pushed or pulled somewhere else.

	 */

	if (p->nr_cpus_allowed != 1 &&

	    cpudl_find(&rq->rd->cpudl, p, NULL) != -1)

	    cpudl_find(&rq->rd->cpudl, p, NULL))

		return;



	resched_curr(rq);
@@ -1811,7 +1811,7 @@ static int find_later_rq(struct task_struct *task) 
	 * We have to consider system topology and task affinity

	 * first, then we can look for a suitable cpu.

	 */

	if (cpudl_find(&task_rq(task)->rd->cpudl, task, later_mask) == -1)

	if (!cpudl_find(&task_rq(task)->rd->cpudl, task, later_mask))

		return -1;



	/*

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