diff options
Diffstat (limited to 'kernel/sched_fair.c')
| -rw-r--r-- | kernel/sched_fair.c | 59 |
1 files changed, 31 insertions, 28 deletions
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c index ce39282d9c0..892616bf2c7 100644 --- a/kernel/sched_fair.c +++ b/kernel/sched_fair.c @@ -194,6 +194,8 @@ __enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se) update_load_add(&cfs_rq->load, se->load.weight); cfs_rq->nr_running++; se->on_rq = 1; + + schedstat_add(cfs_rq, wait_runtime, se->wait_runtime); } static inline void @@ -205,6 +207,8 @@ __dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se) update_load_sub(&cfs_rq->load, se->load.weight); cfs_rq->nr_running--; se->on_rq = 0; + + schedstat_add(cfs_rq, wait_runtime, -se->wait_runtime); } static inline struct rb_node *first_fair(struct cfs_rq *cfs_rq) @@ -291,7 +295,7 @@ niced_granularity(struct sched_entity *curr, unsigned long granularity) /* * It will always fit into 'long': */ - return (long) (tmp >> WMULT_SHIFT); + return (long) (tmp >> (WMULT_SHIFT-NICE_0_SHIFT)); } static inline void @@ -574,7 +578,6 @@ static void __enqueue_sleeper(struct cfs_rq *cfs_rq, struct sched_entity *se) prev_runtime = se->wait_runtime; __add_wait_runtime(cfs_rq, se, delta_fair); - schedstat_add(cfs_rq, wait_runtime, se->wait_runtime); delta_fair = se->wait_runtime - prev_runtime; /* @@ -662,7 +665,6 @@ dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int sleep) if (tsk->state & TASK_UNINTERRUPTIBLE) se->block_start = rq_of(cfs_rq)->clock; } - cfs_rq->wait_runtime -= se->wait_runtime; #endif } __dequeue_entity(cfs_rq, se); @@ -671,22 +673,39 @@ dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int sleep) /* * Preempt the current task with a newly woken task if needed: */ -static int +static void __check_preempt_curr_fair(struct cfs_rq *cfs_rq, struct sched_entity *se, struct sched_entity *curr, unsigned long granularity) { s64 __delta = curr->fair_key - se->fair_key; + unsigned long ideal_runtime, delta_exec; + + /* + * ideal_runtime is compared against sum_exec_runtime, which is + * walltime, hence do not scale. + */ + ideal_runtime = max(sysctl_sched_latency / cfs_rq->nr_running, + (unsigned long)sysctl_sched_min_granularity); + + /* + * If we executed more than what the latency constraint suggests, + * reduce the rescheduling granularity. This way the total latency + * of how much a task is not scheduled converges to + * sysctl_sched_latency: + */ + delta_exec = curr->sum_exec_runtime - curr->prev_sum_exec_runtime; + if (delta_exec > ideal_runtime) + granularity = 0; /* * Take scheduling granularity into account - do not * preempt the current task unless the best task has * a larger than sched_granularity fairness advantage: + * + * scale granularity as key space is in fair_clock. */ - if (__delta > niced_granularity(curr, granularity)) { + if (__delta > niced_granularity(curr, granularity)) resched_task(rq_of(cfs_rq)->curr); - return 1; - } - return 0; } static inline void @@ -702,6 +721,7 @@ set_next_entity(struct cfs_rq *cfs_rq, struct sched_entity *se) update_stats_wait_end(cfs_rq, se); update_stats_curr_start(cfs_rq, se); set_cfs_rq_curr(cfs_rq, se); + se->prev_sum_exec_runtime = se->sum_exec_runtime; } static struct sched_entity *pick_next_entity(struct cfs_rq *cfs_rq) @@ -731,7 +751,6 @@ static void put_prev_entity(struct cfs_rq *cfs_rq, struct sched_entity *prev) static void entity_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr) { - unsigned long gran, ideal_runtime, delta_exec; struct sched_entity *next; /* @@ -748,22 +767,8 @@ static void entity_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr) if (next == curr) return; - gran = sched_granularity(cfs_rq); - ideal_runtime = niced_granularity(curr, - max(sysctl_sched_latency / cfs_rq->nr_running, - (unsigned long)sysctl_sched_min_granularity)); - /* - * If we executed more than what the latency constraint suggests, - * reduce the rescheduling granularity. This way the total latency - * of how much a task is not scheduled converges to - * sysctl_sched_latency: - */ - delta_exec = curr->sum_exec_runtime - curr->prev_sum_exec_runtime; - if (delta_exec > ideal_runtime) - gran = 0; - - if (__check_preempt_curr_fair(cfs_rq, next, curr, gran)) - curr->prev_sum_exec_runtime = curr->sum_exec_runtime; + __check_preempt_curr_fair(cfs_rq, next, curr, + sched_granularity(cfs_rq)); } /************************************************** @@ -1121,10 +1126,8 @@ static void task_new_fair(struct rq *rq, struct task_struct *p) * The statistical average of wait_runtime is about * -granularity/2, so initialize the task with that: */ - if (sysctl_sched_features & SCHED_FEAT_START_DEBIT) { + if (sysctl_sched_features & SCHED_FEAT_START_DEBIT) se->wait_runtime = -(sched_granularity(cfs_rq) / 2); - schedstat_add(cfs_rq, wait_runtime, se->wait_runtime); - } __enqueue_entity(cfs_rq, se); } |