[PATCH] sched: make vruntime_normalized() cleaner

[Byungchul Park]

in both TASK_ON_RQ_QUEUED case and TASK_ON_RQ_MIGRATING case, the
target task have a normalized vruntime by dequeue_entity(.flags=0).
so we don't need to check this separately with a different condition
statement.

Signed-off-by: Byungchul Park <byungchul.park@xxxxxxx>
---
 kernel/sched/fair.c |   16 ++++------------
 1 file changed, 4 insertions(+), 12 deletions(-)

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 53d0e30..dfe8754 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -7920,14 +7920,14 @@ prio_changed_fair(struct rq *rq, struct task_struct *p, int oldprio)
 
 static inline bool vruntime_normalized(struct task_struct *p)
 {
-	int queued = task_on_rq_queued(p);
 	struct sched_entity *se = &p->se;
 
 	/*
-	 * If it's queued, then the dequeue_entity(.flags=0) will already
-	 * have normalized the vruntime.
+	 * In both TASK_ON_RQ_QUEUED case and TASK_ON_RQ_MIGRATING case,
+	 * the dequeue_entity(.flags=0) will already have normalized the
+	 * vruntime.
 	 */
-	if (queued)
+	if (p->on_rq)
 		return true;
 
 	/*
@@ -7942,14 +7942,6 @@ static inline bool vruntime_normalized(struct task_struct *p)
 	if (!se->sum_exec_runtime || p->state == TASK_WAKING)
 		return true;
 
-	/*
-	 * If it's !queued, then only when the task is sleeping it has a
-	 * non-normalized vruntime, that is, when the task is being migrated
-	 * it has a normailized vruntime.
-	 */
-	if (p->state == TASK_RUNNING)
-		return true;
-
 	return false;
 }
 
-- 
1.7.9.5

> 
> And the problem with tracking the vruntime state is that while it helps
> detach_task_cfs_rq(), attach_task_cfs_rq() is still left wondering what
> it should return to.
> 
> So we do indeed need something to determine, based on the current state,
> if vruntime should be normalized.
> 
> /me ponders moar
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