Commit d425b274 authored by Con Kolivas's avatar Con Kolivas Committed by Linus Torvalds
Browse files

[PATCH] sched: activate SCHED BATCH expired 



To increase the strength of SCHED_BATCH as a scheduling hint we can
activate batch tasks on the expired array since by definition they are
latency insensitive tasks.

Signed-off-by: default avatarCon Kolivas <kernel@kolivas.org>
Acked-by: default avatarIngo Molnar <mingo@elte.hu>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 7c4bb1f9

include/linux/sched.h

+1 −0
Original line number Diff line number Diff line
@@ -484,6 +484,7 @@ struct signal_struct { 
#define MAX_PRIO		(MAX_RT_PRIO + 40)



#define rt_task(p)		(unlikely((p)->prio < MAX_RT_PRIO))

#define batch_task(p)		(unlikely((p)->policy == SCHED_BATCH))



/*

 * Some day this will be a full-fledged user tracking system..

kernel/sched.c

+7 −3
Original line number Diff line number Diff line
@@ -667,9 +667,13 @@ static int effective_prio(task_t *p) 
/*

 * __activate_task - move a task to the runqueue.

 */

static inline void __activate_task(task_t *p, runqueue_t *rq)

static void __activate_task(task_t *p, runqueue_t *rq)

{

	enqueue_task(p, rq->active);

	prio_array_t *target = rq->active;



	if (batch_task(p))

		target = rq->expired;

	enqueue_task(p, target);

	rq->nr_running++;

}
@@ -688,7 +692,7 @@ static int recalc_task_prio(task_t *p, unsigned long long now) 
	unsigned long long __sleep_time = now - p->timestamp;

	unsigned long sleep_time;



	if (unlikely(p->policy == SCHED_BATCH))

	if (batch_task(p))

		sleep_time = 0;

	else {

		if (__sleep_time > NS_MAX_SLEEP_AVG)