From f269ae0469fc882332bdfb5db15d3c1315fe2a10 Mon Sep 17 00:00:00 2001 From: Paul Turner Date: Thu, 4 Oct 2012 13:18:31 +0200 Subject: [PATCH] sched: Update_cfs_shares at period edge Now that our measurement intervals are small (~1ms) we can amortize the posting of update_shares() to be about each period overflow. This is a large cost saving for frequently switching tasks. Signed-off-by: Paul Turner Reviewed-by: Ben Segall Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/20120823141507.200772172@google.com Signed-off-by: Ingo Molnar --- kernel/sched/fair.c | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index dcc27d8ae6ba..002a7697f437 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -1187,6 +1187,7 @@ static void update_cfs_rq_blocked_load(struct cfs_rq *cfs_rq, int force_update) } __update_cfs_rq_tg_load_contrib(cfs_rq, force_update); + update_cfs_shares(cfs_rq); } static inline void update_rq_runnable_avg(struct rq *rq, int runnable) @@ -1396,9 +1397,8 @@ enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int flags) * Update run-time statistics of the 'current'. */ update_curr(cfs_rq); - enqueue_entity_load_avg(cfs_rq, se, flags & ENQUEUE_WAKEUP); account_entity_enqueue(cfs_rq, se); - update_cfs_shares(cfs_rq); + enqueue_entity_load_avg(cfs_rq, se, flags & ENQUEUE_WAKEUP); if (flags & ENQUEUE_WAKEUP) { place_entity(cfs_rq, se, 0); @@ -1471,7 +1471,6 @@ dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int flags) * Update run-time statistics of the 'current'. */ update_curr(cfs_rq); - dequeue_entity_load_avg(cfs_rq, se, flags & DEQUEUE_SLEEP); update_stats_dequeue(cfs_rq, se); if (flags & DEQUEUE_SLEEP) { @@ -1491,8 +1490,8 @@ dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int flags) if (se != cfs_rq->curr) __dequeue_entity(cfs_rq, se); - se->on_rq = 0; account_entity_dequeue(cfs_rq, se); + dequeue_entity_load_avg(cfs_rq, se, flags & DEQUEUE_SLEEP); /* * Normalize the entity after updating the min_vruntime because the @@ -1506,7 +1505,7 @@ dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int flags) return_cfs_rq_runtime(cfs_rq); update_min_vruntime(cfs_rq); - update_cfs_shares(cfs_rq); + se->on_rq = 0; } /* @@ -2518,8 +2517,8 @@ enqueue_task_fair(struct rq *rq, struct task_struct *p, int flags) if (cfs_rq_throttled(cfs_rq)) break; - update_cfs_shares(cfs_rq); update_entity_load_avg(se, 1); + update_cfs_rq_blocked_load(cfs_rq, 0); } if (!se) { @@ -2579,8 +2578,8 @@ static void dequeue_task_fair(struct rq *rq, struct task_struct *p, int flags) if (cfs_rq_throttled(cfs_rq)) break; - update_cfs_shares(cfs_rq); update_entity_load_avg(se, 1); + update_cfs_rq_blocked_load(cfs_rq, 0); } if (!se) { @@ -5639,8 +5638,11 @@ int sched_group_set_shares(struct task_group *tg, unsigned long shares) se = tg->se[i]; /* Propagate contribution to hierarchy */ raw_spin_lock_irqsave(&rq->lock, flags); - for_each_sched_entity(se) + for_each_sched_entity(se) { update_cfs_shares(group_cfs_rq(se)); + /* update contribution to parent */ + update_entity_load_avg(se, 1); + } raw_spin_unlock_irqrestore(&rq->lock, flags); }