[PATCH 3/4] Remove dl_new

From: Luca Abeni
Date: Mon Feb 22 2016 - 05:57:49 EST


switched_to_dl() can be used instead
---
kernel/sched/core.c | 1 -
kernel/sched/deadline.c | 28 +++++-----------------------
2 files changed, 5 insertions(+), 24 deletions(-)

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 5dc12db..4246b1b 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -2183,7 +2183,6 @@ void __dl_clear_params(struct task_struct *p)
dl_se->dl_bw = 0;

dl_se->dl_throttled = 0;
- dl_se->dl_new = 1;
dl_se->dl_yielded = 0;
}

diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index 959e7b7..12cb934 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -355,8 +355,6 @@ 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);
-
/*
* We use the regular wall clock time to set deadlines in the
* future; in fact, we must consider execution overheads (time
@@ -364,7 +362,6 @@ 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;
}

/*
@@ -503,15 +500,6 @@ 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;
@@ -608,16 +596,6 @@ 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.
*/
@@ -920,7 +898,7 @@ 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);
@@ -1738,6 +1716,10 @@ 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 (p->dl.deadline <= rq_clock(rq)) {
+ setup_new_dl_entity(&p->dl, &p->dl);
+ }
+
__dl_add_ac(rq, p->dl.dl_bw);
if (task_on_rq_queued(p) && rq->curr != p) {
#ifdef CONFIG_SMP
--
2.5.0