diff options
Diffstat (limited to 'kernel/sched/deadline.c')
-rw-r--r-- | kernel/sched/deadline.c | 91 |
1 files changed, 53 insertions, 38 deletions
diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c index 3958bc576d67..7f6de4316990 100644 --- a/kernel/sched/deadline.c +++ b/kernel/sched/deadline.c @@ -16,20 +16,6 @@ */ #include "sched.h" -static inline int dl_time_before(u64 a, u64 b) -{ - return (s64)(a - b) < 0; -} - -/* - * Tells if entity @a should preempt entity @b. - */ -static inline -int dl_entity_preempt(struct sched_dl_entity *a, struct sched_dl_entity *b) -{ - return dl_time_before(a->deadline, b->deadline); -} - static inline struct task_struct *dl_task_of(struct sched_dl_entity *dl_se) { return container_of(dl_se, struct task_struct, dl); @@ -242,7 +228,8 @@ static void check_preempt_curr_dl(struct rq *rq, struct task_struct *p, * one, and to (try to!) reconcile itself with its own scheduling * parameters. */ -static inline void setup_new_dl_entity(struct sched_dl_entity *dl_se) +static inline void setup_new_dl_entity(struct sched_dl_entity *dl_se, + struct sched_dl_entity *pi_se) { struct dl_rq *dl_rq = dl_rq_of_se(dl_se); struct rq *rq = rq_of_dl_rq(dl_rq); @@ -254,8 +241,8 @@ static inline void setup_new_dl_entity(struct sched_dl_entity *dl_se) * future; in fact, we must consider execution overheads (time * spent on hardirq context, etc.). */ - dl_se->deadline = rq_clock(rq) + dl_se->dl_deadline; - dl_se->runtime = dl_se->dl_runtime; + dl_se->deadline = rq_clock(rq) + pi_se->dl_deadline; + dl_se->runtime = pi_se->dl_runtime; dl_se->dl_new = 0; } @@ -277,11 +264,23 @@ static inline void setup_new_dl_entity(struct sched_dl_entity *dl_se) * could happen are, typically, a entity voluntarily trying to overcome its * runtime, or it just underestimated it during sched_setscheduler_ex(). */ -static void replenish_dl_entity(struct sched_dl_entity *dl_se) +static void replenish_dl_entity(struct sched_dl_entity *dl_se, + struct sched_dl_entity *pi_se) { struct dl_rq *dl_rq = dl_rq_of_se(dl_se); struct rq *rq = rq_of_dl_rq(dl_rq); + BUG_ON(pi_se->dl_runtime <= 0); + + /* + * This could be the case for a !-dl task that is boosted. + * Just go with full inherited parameters. + */ + if (dl_se->dl_deadline == 0) { + dl_se->deadline = rq_clock(rq) + pi_se->dl_deadline; + dl_se->runtime = pi_se->dl_runtime; + } + /* * We keep moving the deadline away until we get some * available runtime for the entity. This ensures correct @@ -289,8 +288,8 @@ static void replenish_dl_entity(struct sched_dl_entity *dl_se) * arbitrary large. */ while (dl_se->runtime <= 0) { - dl_se->deadline += dl_se->dl_period; - dl_se->runtime += dl_se->dl_runtime; + dl_se->deadline += pi_se->dl_period; + dl_se->runtime += pi_se->dl_runtime; } /* @@ -309,8 +308,8 @@ static void replenish_dl_entity(struct sched_dl_entity *dl_se) lag_once = true; printk_sched("sched: DL replenish lagged to much\n"); } - dl_se->deadline = rq_clock(rq) + dl_se->dl_deadline; - dl_se->runtime = dl_se->dl_runtime; + dl_se->deadline = rq_clock(rq) + pi_se->dl_deadline; + dl_se->runtime = pi_se->dl_runtime; } } @@ -337,7 +336,8 @@ static void replenish_dl_entity(struct sched_dl_entity *dl_se) * task with deadline equal to period this is the same of using * dl_deadline instead of dl_period in the equation above. */ -static bool dl_entity_overflow(struct sched_dl_entity *dl_se, u64 t) +static bool dl_entity_overflow(struct sched_dl_entity *dl_se, + struct sched_dl_entity *pi_se, u64 t) { u64 left, right; @@ -359,8 +359,8 @@ static bool dl_entity_overflow(struct sched_dl_entity *dl_se, u64 t) * of anything below microseconds resolution is actually fiction * (but still we want to give the user that illusion >;). */ - left = (dl_se->dl_period >> 10) * (dl_se->runtime >> 10); - right = ((dl_se->deadline - t) >> 10) * (dl_se->dl_runtime >> 10); + left = (pi_se->dl_period >> 10) * (dl_se->runtime >> 10); + right = ((dl_se->deadline - t) >> 10) * (pi_se->dl_runtime >> 10); return dl_time_before(right, left); } @@ -374,7 +374,8 @@ static bool dl_entity_overflow(struct sched_dl_entity *dl_se, u64 t) * - using the remaining runtime with the current deadline would make * the entity exceed its bandwidth. */ -static void update_dl_entity(struct sched_dl_entity *dl_se) +static void update_dl_entity(struct sched_dl_entity *dl_se, + struct sched_dl_entity *pi_se) { struct dl_rq *dl_rq = dl_rq_of_se(dl_se); struct rq *rq = rq_of_dl_rq(dl_rq); @@ -384,14 +385,14 @@ static void update_dl_entity(struct sched_dl_entity *dl_se) * the actual scheduling parameters have to be "renewed". */ if (dl_se->dl_new) { - setup_new_dl_entity(dl_se); + setup_new_dl_entity(dl_se, pi_se); return; } if (dl_time_before(dl_se->deadline, rq_clock(rq)) || - dl_entity_overflow(dl_se, rq_clock(rq))) { - dl_se->deadline = rq_clock(rq) + dl_se->dl_deadline; - dl_se->runtime = dl_se->dl_runtime; + dl_entity_overflow(dl_se, pi_se, rq_clock(rq))) { + dl_se->deadline = rq_clock(rq) + pi_se->dl_deadline; + dl_se->runtime = pi_se->dl_runtime; } } @@ -405,7 +406,7 @@ static void update_dl_entity(struct sched_dl_entity *dl_se) * actually started or not (i.e., the replenishment instant is in * the future or in the past). */ -static int start_dl_timer(struct sched_dl_entity *dl_se) +static int start_dl_timer(struct sched_dl_entity *dl_se, bool boosted) { struct dl_rq *dl_rq = dl_rq_of_se(dl_se); struct rq *rq = rq_of_dl_rq(dl_rq); @@ -414,6 +415,8 @@ static int start_dl_timer(struct sched_dl_entity *dl_se) unsigned long range; s64 delta; + if (boosted) + return 0; /* * We want the timer to fire at the deadline, but considering * that it is actually coming from rq->clock and not from @@ -573,7 +576,7 @@ static void update_curr_dl(struct rq *rq) dl_se->runtime -= delta_exec; if (dl_runtime_exceeded(rq, dl_se)) { __dequeue_task_dl(rq, curr, 0); - if (likely(start_dl_timer(dl_se))) + if (likely(start_dl_timer(dl_se, curr->dl.dl_boosted))) dl_se->dl_throttled = 1; else enqueue_task_dl(rq, curr, ENQUEUE_REPLENISH); @@ -728,7 +731,8 @@ static void __dequeue_dl_entity(struct sched_dl_entity *dl_se) } static void -enqueue_dl_entity(struct sched_dl_entity *dl_se, int flags) +enqueue_dl_entity(struct sched_dl_entity *dl_se, + struct sched_dl_entity *pi_se, int flags) { BUG_ON(on_dl_rq(dl_se)); @@ -738,9 +742,9 @@ enqueue_dl_entity(struct sched_dl_entity *dl_se, int flags) * we want a replenishment of its runtime. */ if (!dl_se->dl_new && flags & ENQUEUE_REPLENISH) - replenish_dl_entity(dl_se); + replenish_dl_entity(dl_se, pi_se); else - update_dl_entity(dl_se); + update_dl_entity(dl_se, pi_se); __enqueue_dl_entity(dl_se); } @@ -752,6 +756,18 @@ static void dequeue_dl_entity(struct sched_dl_entity *dl_se) static void enqueue_task_dl(struct rq *rq, struct task_struct *p, int flags) { + struct task_struct *pi_task = rt_mutex_get_top_task(p); + struct sched_dl_entity *pi_se = &p->dl; + + /* + * Use the scheduling parameters of the top pi-waiter + * task if we have one and its (relative) deadline is + * smaller than our one... OTW we keep our runtime and + * deadline. + */ + if (pi_task && p->dl.dl_boosted && dl_prio(pi_task->normal_prio)) + pi_se = &pi_task->dl; + /* * If p is throttled, we do nothing. In fact, if it exhausted * its budget it needs a replenishment and, since it now is on @@ -761,7 +777,7 @@ static void enqueue_task_dl(struct rq *rq, struct task_struct *p, int flags) if (p->dl.dl_throttled) return; - enqueue_dl_entity(&p->dl, flags); + enqueue_dl_entity(&p->dl, pi_se, flags); if (!task_current(rq, p) && p->nr_cpus_allowed > 1) enqueue_pushable_dl_task(rq, p); @@ -985,8 +1001,7 @@ static void task_dead_dl(struct task_struct *p) { struct hrtimer *timer = &p->dl.dl_timer; - if (hrtimer_active(timer)) - hrtimer_try_to_cancel(timer); + hrtimer_cancel(timer); } static void set_curr_task_dl(struct rq *rq) |