min_vruntime update when a task is sleeping/migrating

From: Pavan Kondeti
Date: Thu Feb 23 2017 - 01:15:56 EST

Hi Peter,

The comment and the code around 2nd update_min_vruntime() call in
dequeue_entity() are not matching. If I understand commit b60205c7c558
("sched/fair: Fix min_vruntime tracking") correctly, the check is
inverted there. We want to update min_vruntime when a task is
sleeping/migrating. is my understanding right?

static void
dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int flags)

* Now advance min_vruntime if @se was the entity holding it back,
* except when: DEQUEUE_SAVE && !DEQUEUE_MOVE, in this case we'll be
* put back on, and if we advance min_vruntime, we'll be placed back
* further than we started -- ie. we'll be penalized.


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