2022-08-26 10:05:14

by Shang XiaoJing

[permalink] [raw]
Subject: [PATCH -next v2] sched/deadline: Add replenish_dl_new_period helper

Wrap repeated code in helper function replenish_dl_new_period, which set
the deadline and runtime of input dl_se based on pi_of(dl_se). Note that
setup_new_dl_entity originally set the deadline and runtime base on
dl_se, which should equals to pi_of(dl_se) for non-boosted task.

Signed-off-by: Shang XiaoJing <[email protected]>
---
changes in v2:
- fix comment msg
- pick a more descriptive function name rather than start_new_instance.
---
kernel/sched/deadline.c | 23 +++++++++++++----------
1 file changed, 13 insertions(+), 10 deletions(-)

diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index 34271aff4712..3bf4b12ec5b7 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -770,6 +770,14 @@ static void enqueue_task_dl(struct rq *rq, struct task_struct *p, int flags);
static void __dequeue_task_dl(struct rq *rq, struct task_struct *p, int flags);
static void check_preempt_curr_dl(struct rq *rq, struct task_struct *p, int flags);

+static inline void replenish_dl_new_period(struct sched_dl_entity *dl_se,
+ struct rq *rq)
+{
+ /* for non-boosted task, pi_of(dl_se) == dl_se */
+ dl_se->deadline = rq_clock(rq) + pi_of(dl_se)->dl_deadline;
+ dl_se->runtime = pi_of(dl_se)->dl_runtime;
+}
+
/*
* We are being explicitly informed that a new instance is starting,
* and this means that:
@@ -803,8 +811,7 @@ 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;
+ replenish_dl_new_period(dl_se, rq);
}

/*
@@ -836,10 +843,8 @@ static void replenish_dl_entity(struct sched_dl_entity *dl_se)
* 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_of(dl_se)->dl_deadline;
- dl_se->runtime = pi_of(dl_se)->dl_runtime;
- }
+ if (dl_se->dl_deadline == 0)
+ replenish_dl_new_period(dl_se, rq);

if (dl_se->dl_yielded && dl_se->runtime > 0)
dl_se->runtime = 0;
@@ -866,8 +871,7 @@ static void replenish_dl_entity(struct sched_dl_entity *dl_se)
*/
if (dl_time_before(dl_se->deadline, rq_clock(rq))) {
printk_deferred_once("sched: DL replenish lagged too much\n");
- dl_se->deadline = rq_clock(rq) + pi_of(dl_se)->dl_deadline;
- dl_se->runtime = pi_of(dl_se)->dl_runtime;
+ replenish_dl_new_period(dl_se, rq);
}

if (dl_se->dl_yielded)
@@ -1024,8 +1028,7 @@ static void update_dl_entity(struct sched_dl_entity *dl_se)
return;
}

- dl_se->deadline = rq_clock(rq) + pi_of(dl_se)->dl_deadline;
- dl_se->runtime = pi_of(dl_se)->dl_runtime;
+ replenish_dl_new_period(dl_se, rq);
}
}

--
2.17.1


Subject: Re: [PATCH -next v2] sched/deadline: Add replenish_dl_new_period helper

On 8/26/22 12:00, Shang XiaoJing wrote:
> Wrap repeated code in helper function replenish_dl_new_period, which set
> the deadline and runtime of input dl_se based on pi_of(dl_se). Note that
> setup_new_dl_entity originally set the deadline and runtime base on
> dl_se, which should equals to pi_of(dl_se) for non-boosted task.
>
> Signed-off-by: Shang XiaoJing <[email protected]>

Reviewed-by: Daniel Bristot de Oliveira <[email protected]>

-- Daniel

Subject: [tip: sched/core] sched/deadline: Add replenish_dl_new_period helper

The following commit has been merged into the sched/core branch of tip:

Commit-ID: 96458e7f7dc5ad14bd7577cbf1638e1504ad79dd
Gitweb: https://git.kernel.org/tip/96458e7f7dc5ad14bd7577cbf1638e1504ad79dd
Author: Shang XiaoJing <[email protected]>
AuthorDate: Fri, 26 Aug 2022 18:00:37 +08:00
Committer: Peter Zijlstra <[email protected]>
CommitterDate: Thu, 01 Sep 2022 11:19:54 +02:00

sched/deadline: Add replenish_dl_new_period helper

Wrap repeated code in helper function replenish_dl_new_period, which set
the deadline and runtime of input dl_se based on pi_of(dl_se). Note that
setup_new_dl_entity originally set the deadline and runtime base on
dl_se, which should equals to pi_of(dl_se) for non-boosted task.

Signed-off-by: Shang XiaoJing <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Reviewed-by: Daniel Bristot de Oliveira <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
---
kernel/sched/deadline.c | 23 +++++++++++++----------
1 file changed, 13 insertions(+), 10 deletions(-)

diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index 34271af..3bf4b12 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -770,6 +770,14 @@ static void enqueue_task_dl(struct rq *rq, struct task_struct *p, int flags);
static void __dequeue_task_dl(struct rq *rq, struct task_struct *p, int flags);
static void check_preempt_curr_dl(struct rq *rq, struct task_struct *p, int flags);

+static inline void replenish_dl_new_period(struct sched_dl_entity *dl_se,
+ struct rq *rq)
+{
+ /* for non-boosted task, pi_of(dl_se) == dl_se */
+ dl_se->deadline = rq_clock(rq) + pi_of(dl_se)->dl_deadline;
+ dl_se->runtime = pi_of(dl_se)->dl_runtime;
+}
+
/*
* We are being explicitly informed that a new instance is starting,
* and this means that:
@@ -803,8 +811,7 @@ 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;
+ replenish_dl_new_period(dl_se, rq);
}

/*
@@ -836,10 +843,8 @@ static void replenish_dl_entity(struct sched_dl_entity *dl_se)
* 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_of(dl_se)->dl_deadline;
- dl_se->runtime = pi_of(dl_se)->dl_runtime;
- }
+ if (dl_se->dl_deadline == 0)
+ replenish_dl_new_period(dl_se, rq);

if (dl_se->dl_yielded && dl_se->runtime > 0)
dl_se->runtime = 0;
@@ -866,8 +871,7 @@ static void replenish_dl_entity(struct sched_dl_entity *dl_se)
*/
if (dl_time_before(dl_se->deadline, rq_clock(rq))) {
printk_deferred_once("sched: DL replenish lagged too much\n");
- dl_se->deadline = rq_clock(rq) + pi_of(dl_se)->dl_deadline;
- dl_se->runtime = pi_of(dl_se)->dl_runtime;
+ replenish_dl_new_period(dl_se, rq);
}

if (dl_se->dl_yielded)
@@ -1024,8 +1028,7 @@ static void update_dl_entity(struct sched_dl_entity *dl_se)
return;
}

- dl_se->deadline = rq_clock(rq) + pi_of(dl_se)->dl_deadline;
- dl_se->runtime = pi_of(dl_se)->dl_runtime;
+ replenish_dl_new_period(dl_se, rq);
}
}