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-rw-r--r--kernel/sched/deadline.c66
1 files changed, 32 insertions, 34 deletions
diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index cd64c979d0e1..affd97ec9f65 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -352,7 +352,15 @@ static inline void setup_new_dl_entity(struct sched_dl_entity *dl_se,
struct dl_rq *dl_rq = dl_rq_of_se(dl_se);
struct rq *rq = rq_of_dl_rq(dl_rq);
- WARN_ON(!dl_se->dl_new || dl_se->dl_throttled);
+ WARN_ON(dl_time_before(rq_clock(rq), dl_se->deadline));
+
+ /*
+ * We are racing with the deadline timer. So, do nothing because
+ * the deadline timer handler will take care of properly recharging
+ * the runtime and postponing the deadline
+ */
+ if (dl_se->dl_throttled)
+ return;
/*
* We use the regular wall clock time to set deadlines in the
@@ -361,7 +369,6 @@ static inline void setup_new_dl_entity(struct sched_dl_entity *dl_se,
*/
dl_se->deadline = rq_clock(rq) + pi_se->dl_deadline;
dl_se->runtime = pi_se->dl_runtime;
- dl_se->dl_new = 0;
}
/*
@@ -399,6 +406,9 @@ static void replenish_dl_entity(struct sched_dl_entity *dl_se,
dl_se->runtime = pi_se->dl_runtime;
}
+ if (dl_se->dl_yielded && dl_se->runtime > 0)
+ dl_se->runtime = 0;
+
/*
* We keep moving the deadline away until we get some
* available runtime for the entity. This ensures correct
@@ -420,7 +430,7 @@ static void replenish_dl_entity(struct sched_dl_entity *dl_se,
* entity.
*/
if (dl_time_before(dl_se->deadline, rq_clock(rq))) {
- printk_deferred_once("sched: DL replenish lagged to much\n");
+ printk_deferred_once("sched: DL replenish lagged too much\n");
dl_se->deadline = rq_clock(rq) + pi_se->dl_deadline;
dl_se->runtime = pi_se->dl_runtime;
}
@@ -500,15 +510,6 @@ static void update_dl_entity(struct sched_dl_entity *dl_se,
struct dl_rq *dl_rq = dl_rq_of_se(dl_se);
struct rq *rq = rq_of_dl_rq(dl_rq);
- /*
- * The arrival of a new instance needs special treatment, i.e.,
- * the actual scheduling parameters have to be "renewed".
- */
- if (dl_se->dl_new) {
- setup_new_dl_entity(dl_se, pi_se);
- return;
- }
-
if (dl_time_before(dl_se->deadline, rq_clock(rq)) ||
dl_entity_overflow(dl_se, pi_se, rq_clock(rq))) {
dl_se->deadline = rq_clock(rq) + pi_se->dl_deadline;
@@ -605,16 +606,6 @@ static enum hrtimer_restart dl_task_timer(struct hrtimer *timer)
}
/*
- * This is possible if switched_from_dl() raced against a running
- * callback that took the above !dl_task() path and we've since then
- * switched back into SCHED_DEADLINE.
- *
- * There's nothing to do except drop our task reference.
- */
- if (dl_se->dl_new)
- goto unlock;
-
- /*
* The task might have been boosted by someone else and might be in the
* boosting/deboosting path, its not throttled.
*/
@@ -726,6 +717,10 @@ static void update_curr_dl(struct rq *rq)
if (!dl_task(curr) || !on_dl_rq(dl_se))
return;
+ /* Kick cpufreq (see the comment in linux/cpufreq.h). */
+ if (cpu_of(rq) == smp_processor_id())
+ cpufreq_trigger_update(rq_clock(rq));
+
/*
* Consumed budget is computed considering the time as
* observed by schedulable tasks (excluding time spent
@@ -735,8 +730,11 @@ static void update_curr_dl(struct rq *rq)
* approach need further study.
*/
delta_exec = rq_clock_task(rq) - curr->se.exec_start;
- if (unlikely((s64)delta_exec <= 0))
+ if (unlikely((s64)delta_exec <= 0)) {
+ if (unlikely(dl_se->dl_yielded))
+ goto throttle;
return;
+ }
schedstat_set(curr->se.statistics.exec_max,
max(curr->se.statistics.exec_max, delta_exec));
@@ -749,8 +747,10 @@ static void update_curr_dl(struct rq *rq)
sched_rt_avg_update(rq, delta_exec);
- dl_se->runtime -= dl_se->dl_yielded ? 0 : delta_exec;
- if (dl_runtime_exceeded(dl_se)) {
+ dl_se->runtime -= delta_exec;
+
+throttle:
+ if (dl_runtime_exceeded(dl_se) || dl_se->dl_yielded) {
dl_se->dl_throttled = 1;
__dequeue_task_dl(rq, curr, 0);
if (unlikely(dl_se->dl_boosted || !start_dl_timer(curr)))
@@ -917,7 +917,7 @@ enqueue_dl_entity(struct sched_dl_entity *dl_se,
* parameters of the task might need updating. Otherwise,
* we want a replenishment of its runtime.
*/
- if (dl_se->dl_new || flags & ENQUEUE_WAKEUP)
+ if (flags & ENQUEUE_WAKEUP)
update_dl_entity(dl_se, pi_se);
else if (flags & ENQUEUE_REPLENISH)
replenish_dl_entity(dl_se, pi_se);
@@ -994,18 +994,14 @@ static void dequeue_task_dl(struct rq *rq, struct task_struct *p, int flags)
*/
static void yield_task_dl(struct rq *rq)
{
- struct task_struct *p = rq->curr;
-
/*
* We make the task go to sleep until its current deadline by
* forcing its runtime to zero. This way, update_curr_dl() stops
* it and the bandwidth timer will wake it up and will give it
* new scheduling parameters (thanks to dl_yielded=1).
*/
- if (p->dl.runtime > 0) {
- rq->curr->dl.dl_yielded = 1;
- p->dl.runtime = 0;
- }
+ rq->curr->dl.dl_yielded = 1;
+
update_rq_clock(rq);
update_curr_dl(rq);
/*
@@ -1722,6 +1718,9 @@ static void switched_from_dl(struct rq *rq, struct task_struct *p)
*/
static void switched_to_dl(struct rq *rq, struct task_struct *p)
{
+ if (dl_time_before(p->dl.deadline, rq_clock(rq)))
+ setup_new_dl_entity(&p->dl, &p->dl);
+
if (task_on_rq_queued(p) && rq->curr != p) {
#ifdef CONFIG_SMP
if (p->nr_cpus_allowed > 1 && rq->dl.overloaded)
@@ -1768,8 +1767,7 @@ static void prio_changed_dl(struct rq *rq, struct task_struct *p,
*/
resched_curr(rq);
#endif /* CONFIG_SMP */
- } else
- switched_to_dl(rq, p);
+ }
}
const struct sched_class dl_sched_class = {