diff options
| -rw-r--r-- | kernel/sched/fair.c | 46 |
1 files changed, 33 insertions, 13 deletions
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 1c0ef435a7aa..61b826fa0680 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -884,6 +884,26 @@ struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq) } /* + * HACK, stash a copy of deadline at the point of pick in vlag, + * which isn't used until dequeue. + */ +static inline void set_protect_slice(struct sched_entity *se) +{ + se->vlag = se->deadline; +} + +static inline bool protect_slice(struct sched_entity *se) +{ + return se->vlag == se->deadline; +} + +static inline void cancel_protect_slice(struct sched_entity *se) +{ + if (protect_slice(se)) + se->vlag = se->deadline + 1; +} + +/* * Earliest Eligible Virtual Deadline First * * In order to provide latency guarantees for different request sizes @@ -919,11 +939,7 @@ static struct sched_entity *pick_eevdf(struct cfs_rq *cfs_rq) if (curr && (!curr->on_rq || !entity_eligible(cfs_rq, curr))) curr = NULL; - /* - * Once selected, run a task until it either becomes non-eligible or - * until it gets a new slice. See the HACK in set_next_entity(). - */ - if (sched_feat(RUN_TO_PARITY) && curr && curr->vlag == curr->deadline) + if (sched_feat(RUN_TO_PARITY) && curr && protect_slice(curr)) return curr; /* Pick the leftmost entity if it's eligible */ @@ -5528,11 +5544,8 @@ set_next_entity(struct cfs_rq *cfs_rq, struct sched_entity *se) update_stats_wait_end_fair(cfs_rq, se); __dequeue_entity(cfs_rq, se); update_load_avg(cfs_rq, se, UPDATE_TG); - /* - * HACK, stash a copy of deadline at the point of pick in vlag, - * which isn't used until dequeue. - */ - se->vlag = se->deadline; + + set_protect_slice(se); } update_stats_curr_start(cfs_rq, se); @@ -8781,8 +8794,15 @@ static void check_preempt_wakeup_fair(struct rq *rq, struct task_struct *p, int * Preempt an idle entity in favor of a non-idle entity (and don't preempt * in the inverse case). */ - if (cse_is_idle && !pse_is_idle) + if (cse_is_idle && !pse_is_idle) { + /* + * When non-idle entity preempt an idle entity, + * don't give idle entity slice protection. + */ + cancel_protect_slice(se); goto preempt; + } + if (cse_is_idle != pse_is_idle) return; @@ -8801,8 +8821,8 @@ static void check_preempt_wakeup_fair(struct rq *rq, struct task_struct *p, int * Note that even if @p does not turn out to be the most eligible * task at this moment, current's slice protection will be lost. */ - if (do_preempt_short(cfs_rq, pse, se) && se->vlag == se->deadline) - se->vlag = se->deadline + 1; + if (do_preempt_short(cfs_rq, pse, se)) + cancel_protect_slice(se); /* * If @p has become the most eligible task, force preemption. |