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sched/pelt: Relax the sync of runnable_sum with runnable_avg

Similarly to util_avg and util_sum, don't sync runnable_sum with the low bound of runnable_avg but only ensure that runnable_sum stays in the correct range.

Vincent Guittot committed 4 years ago

Commit 95246d11 parent 7ceb7711 file · +19 −14Browse files

Unified · Split

kernel/sched/fair.c+19−14
@@ -3483,11 +3483,11 @@ update_tg_cfs_util(struct cfs_rq *cfs_rq, struct sched_entity *se, struct cfs_rq · 3482 unmodified lines
34833483 static inline void
34843484 update_tg_cfs_runnable(struct cfs_rq *cfs_rq, struct sched_entity *se, struct cfs_rq *gcfs_rq)
34853485 {
3486− long delta = gcfs_rq->avg.runnable_avg - se->avg.runnable_avg;
3487− u32 divider;
3486+ long delta_sum, delta_avg = gcfs_rq->avg.runnable_avg - se->avg.runnable_avg;
3487+ u32 new_sum, divider;
34883488
34893489 /* Nothing to update */
3490− if (!delta)
3490+ if (!delta_avg)
34913491 return;
34923492
34933493 /*
@@ -3498,11 +3498,16 @@ update_tg_cfs_runnable(struct cfs_rq *cfs_rq, struct sched_entity *se, struct cf · 4 unmodified lines
34983498
34993499 /* Set new sched_entity's runnable */
35003500 se->avg.runnable_avg = gcfs_rq->avg.runnable_avg;
3501− se->avg.runnable_sum = se->avg.runnable_avg * divider;
3501+ new_sum = se->avg.runnable_avg * divider;
3502+ delta_sum = (long)new_sum - (long)se->avg.runnable_sum;
3503+ se->avg.runnable_sum = new_sum;
35023504
35033505 /* Update parent cfs_rq runnable */
3504− add_positive(&cfs_rq->avg.runnable_avg, delta);
3505− cfs_rq->avg.runnable_sum = cfs_rq->avg.runnable_avg * divider;
3506+ add_positive(&cfs_rq->avg.runnable_avg, delta_avg);
3507+ add_positive(&cfs_rq->avg.runnable_sum, delta_sum);
3508+ /* See update_cfs_rq_load_avg() */
3509+ cfs_rq->avg.runnable_sum = max_t(u32, cfs_rq->avg.runnable_sum,
3510+ cfs_rq->avg.runnable_avg * PELT_MIN_DIVIDER);
35063511 }
35073512
35083513 static inline void
@@ -3702,7 +3707,10 @@ update_cfs_rq_load_avg(u64 now, struct cfs_rq *cfs_rq) · 193 unmodified lines
37023707
37033708 r = removed_runnable;
37043709 sub_positive(&sa->runnable_avg, r);
3705− sa->runnable_sum = sa->runnable_avg * divider;
3710+ sub_positive(&sa->runnable_sum, r * divider);
3711+ /* See sa->util_sum above */
3712+ sa->runnable_sum = max_t(u32, sa->runnable_sum,
3713+ sa->runnable_avg * PELT_MIN_DIVIDER);
37063714
37073715 /*
37083716 * removed_runnable is the unweighted version of removed_load so we
@@ -3789,12 +3797,6 @@ static void attach_entity_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *s · 80 unmodified lines
37893797 */
37903798 static void detach_entity_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *se)
37913799 {
3792− /*
3793− * cfs_rq->avg.period_contrib can be used for both cfs_rq and se.
3794− * See ___update_load_avg() for details.
3795− */
3796− u32 divider = get_pelt_divider(&cfs_rq->avg);
3797−
37983800 dequeue_load_avg(cfs_rq, se);
37993801 sub_positive(&cfs_rq->avg.util_avg, se->avg.util_avg);
38003802 sub_positive(&cfs_rq->avg.util_sum, se->avg.util_sum);
@@ -3803,7 +3805,10 @@ static void detach_entity_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *s · 2 unmodified lines
38033805 cfs_rq->avg.util_avg * PELT_MIN_DIVIDER);
38043806
38053807 sub_positive(&cfs_rq->avg.runnable_avg, se->avg.runnable_avg);
3806− cfs_rq->avg.runnable_sum = cfs_rq->avg.runnable_avg * divider;
3808+ sub_positive(&cfs_rq->avg.runnable_sum, se->avg.runnable_sum);
3809+ /* See update_cfs_rq_load_avg() */
3810+ cfs_rq->avg.runnable_sum = max_t(u32, cfs_rq->avg.runnable_sum,
3811+ cfs_rq->avg.runnable_avg * PELT_MIN_DIVIDER);
38073812
38083813 add_tg_cfs_propagate(cfs_rq, -se->avg.load_sum);
38093814