sched: wakeup preemption fix

wakeup preemption fix: do not make it dependent on p->prio.
Preemption purely depends on ->vruntime.

This improves preemption in mixed-nice-level workloads.

Signed-off-by: Ingo Molnar <[e-mail]>

kernel/sched_fair.c

···
 		if (unlikely(se->load.weight != NICE_0_LOAD))
 			gran = calc_delta_fair(gran, &se->load);
 
-		if (delta > gran) {
-			if (p->prio < curr->prio)
-				resched_task(curr);
-		}
+		if (delta > gran)
+			resched_task(curr);
 	}
 }