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Diffstat (limited to 'kernel/sched/deadline.c')
-rw-r--r--kernel/sched/deadline.c63
1 files changed, 47 insertions, 16 deletions
diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index 5e95145088fd..eac20c557a55 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -503,8 +503,6 @@ 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);
ktime_t now, act;
- ktime_t soft, hard;
- unsigned long range;
s64 delta;
if (boosted)
@@ -527,15 +525,9 @@ static int start_dl_timer(struct sched_dl_entity *dl_se, bool boosted)
if (ktime_us_delta(act, now) < 0)
return 0;
- hrtimer_set_expires(&dl_se->dl_timer, act);
+ hrtimer_start(&dl_se->dl_timer, act, HRTIMER_MODE_ABS);
- soft = hrtimer_get_softexpires(&dl_se->dl_timer);
- hard = hrtimer_get_expires(&dl_se->dl_timer);
- range = ktime_to_ns(ktime_sub(hard, soft));
- __hrtimer_start_range_ns(&dl_se->dl_timer, soft,
- range, HRTIMER_MODE_ABS, 0);
-
- return hrtimer_active(&dl_se->dl_timer);
+ return 1;
}
/*
@@ -640,7 +632,7 @@ void init_dl_task_timer(struct sched_dl_entity *dl_se)
}
static
-int dl_runtime_exceeded(struct rq *rq, struct sched_dl_entity *dl_se)
+int dl_runtime_exceeded(struct sched_dl_entity *dl_se)
{
return (dl_se->runtime <= 0);
}
@@ -684,7 +676,7 @@ 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(rq, dl_se)) {
+ if (dl_runtime_exceeded(dl_se)) {
dl_se->dl_throttled = 1;
__dequeue_task_dl(rq, curr, 0);
if (unlikely(!start_dl_timer(dl_se, curr->dl.dl_boosted)))
@@ -995,7 +987,7 @@ select_task_rq_dl(struct task_struct *p, int cpu, int sd_flag, int flags)
rq = cpu_rq(cpu);
rcu_read_lock();
- curr = ACCESS_ONCE(rq->curr); /* unlocked access */
+ curr = READ_ONCE(rq->curr); /* unlocked access */
/*
* If we are dealing with a -deadline task, we must
@@ -1012,7 +1004,9 @@ select_task_rq_dl(struct task_struct *p, int cpu, int sd_flag, int flags)
(p->nr_cpus_allowed > 1)) {
int target = find_later_rq(p);
- if (target != -1)
+ if (target != -1 &&
+ dl_time_before(p->dl.deadline,
+ cpu_rq(target)->dl.earliest_dl.curr))
cpu = target;
}
rcu_read_unlock();
@@ -1230,6 +1224,32 @@ next_node:
return NULL;
}
+/*
+ * Return the earliest pushable rq's task, which is suitable to be executed
+ * on the CPU, NULL otherwise:
+ */
+static struct task_struct *pick_earliest_pushable_dl_task(struct rq *rq, int cpu)
+{
+ struct rb_node *next_node = rq->dl.pushable_dl_tasks_leftmost;
+ struct task_struct *p = NULL;
+
+ if (!has_pushable_dl_tasks(rq))
+ return NULL;
+
+next_node:
+ if (next_node) {
+ p = rb_entry(next_node, struct task_struct, pushable_dl_tasks);
+
+ if (pick_dl_task(rq, p, cpu))
+ return p;
+
+ next_node = rb_next(next_node);
+ goto next_node;
+ }
+
+ return NULL;
+}
+
static DEFINE_PER_CPU(cpumask_var_t, local_cpu_mask_dl);
static int find_later_rq(struct task_struct *task)
@@ -1333,6 +1353,17 @@ static struct rq *find_lock_later_rq(struct task_struct *task, struct rq *rq)
later_rq = cpu_rq(cpu);
+ if (!dl_time_before(task->dl.deadline,
+ later_rq->dl.earliest_dl.curr)) {
+ /*
+ * Target rq has tasks of equal or earlier deadline,
+ * retrying does not release any lock and is unlikely
+ * to yield a different result.
+ */
+ later_rq = NULL;
+ break;
+ }
+
/* Retry if something changed. */
if (double_lock_balance(rq, later_rq)) {
if (unlikely(task_rq(task) != rq ||
@@ -1514,7 +1545,7 @@ static int pull_dl_task(struct rq *this_rq)
if (src_rq->dl.dl_nr_running <= 1)
goto skip;
- p = pick_next_earliest_dl_task(src_rq, this_cpu);
+ p = pick_earliest_pushable_dl_task(src_rq, this_cpu);
/*
* We found a task to be pulled if:
@@ -1659,7 +1690,7 @@ static void rq_offline_dl(struct rq *rq)
cpudl_clear_freecpu(&rq->rd->cpudl, rq->cpu);
}
-void init_sched_dl_class(void)
+void __init init_sched_dl_class(void)
{
unsigned int i;