Revert "sched: fair: Add strict skip buddy support"

This reverts commit 6f58caae21.

It's not present in newer CAF kernels and Google removed it on their
4.14 devices as well.

Change-Id: I3675cbfe4a37ae9ed31bf3659a545965a0d59c6f
Signed-off-by: Alexander Winkowski <dereference23@outlook.com>

kernel/sched/fair.c

@@ -4255,7 +4255,6 @@ pick_next_entity(struct cfs_rq *cfs_rq, struct sched_entity *curr)
 {
 	struct sched_entity *left = __pick_first_entity(cfs_rq);
 	struct sched_entity *se;
-	bool strict_skip = false;
 
 	/*
 	 * If curr is set we have to see if its left of the leftmost entity
@@ -4275,16 +4274,13 @@ pick_next_entity(struct cfs_rq *cfs_rq, struct sched_entity *curr)
 
 		if (se == curr) {
 			second = __pick_first_entity(cfs_rq);
-			if (sched_feat(STRICT_SKIP_BUDDY))
-				strict_skip = true;
 		} else {
 			second = __pick_next_entity(se);
 			if (!second || (curr && entity_before(curr, second)))
 				second = curr;
 		}
 
-		if (second && (strict_skip ||
-		    wakeup_preempt_entity(second, left) < 1))
+		if (second && wakeup_preempt_entity(second, left) < 1)
 			se = second;
 	}
 

kernel/sched/features.h

@@ -26,12 +26,6 @@ SCHED_FEAT(NEXT_BUDDY, false)
  */
 SCHED_FEAT(LAST_BUDDY, true)
 
-/*
- * skip buddy i.e task called yield() is always skipped and the
- * next entity is selected to run irrespective of the vruntime
- */
-SCHED_FEAT(STRICT_SKIP_BUDDY, true)
-
 /*
  * Consider buddies to be cache hot, decreases the likelyness of a
  * cache buddy being migrated away, increases cache locality.