Commit e5f32a38 authored by Ingo Molnar's avatar Ingo Molnar
Browse files

sched: speed up context-switches a bit 



speed up context-switches a bit by not clearing p->exec_start.

(as a side-effect, this also makes p->exec_start a universal timestamp
available to cache-hot estimations.)

Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 91c234b4

kernel/sched_fair.c

+0 −11
Original line number Diff line number Diff line
@@ -379,15 +379,6 @@ update_stats_curr_start(struct cfs_rq *cfs_rq, struct sched_entity *se) 
	se->exec_start = rq_of(cfs_rq)->clock;

}



/*

 * We are descheduling a task - update its stats:

 */

static inline void

update_stats_curr_end(struct cfs_rq *cfs_rq, struct sched_entity *se)

{

	se->exec_start = 0;

}



/**************************************************

 * Scheduling class queueing methods:

 */
@@ -609,8 +600,6 @@ static void put_prev_entity(struct cfs_rq *cfs_rq, struct sched_entity *prev) 
	if (prev->on_rq)

		update_curr(cfs_rq);



	update_stats_curr_end(cfs_rq, prev);



	check_spread(cfs_rq, prev);

	if (prev->on_rq) {

		update_stats_wait_start(cfs_rq, prev);