[PATCH -next] sched/deadline: Add start_new_instance helper

[Shang XiaoJing]

Wrap repeated code in helper function start_new_instance, which set
the deadline and runtiem 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 <shangxiaojing@xxxxxxxxxx>
---
 kernel/sched/deadline.c | 22 ++++++++++++----------
 1 file changed, 12 insertions(+), 10 deletions(-)

diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index 4a40a462717c..5e9c28847610 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -770,6 +770,13 @@ 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 start_new_instance(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 +810,7 @@ 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;
+	start_new_instance(dl_se, rq);
 }
 
 /*
@@ -836,10 +842,8 @@ 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)
+		start_new_instance(dl_se, rq);
 
 	if (dl_se->dl_yielded && dl_se->runtime > 0)
 		dl_se->runtime = 0;
@@ -866,8 +870,7 @@ 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;
+		start_new_instance(dl_se, rq);
 	}
 
 	if (dl_se->dl_yielded)
@@ -1024,8 +1027,7 @@ 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;
+		start_new_instance(dl_se, rq);
 	}
 }
 
-- 
2.17.1