Commit 7d148be6 authored May 13, 2020 by Vincent Guittot Committed by Peter Zijlstra May 19, 2020

sched/fair: Optimize enqueue_task_fair()

enqueue_task_fair jumps to enqueue_throttle label when cfs_rq_of(se) is
throttled which means that se can't be NULL in such case and we can move
the label after the if (!se) statement. Futhermore, the latter can be
removed because se is always NULL when reaching this point.

Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Phil Auld <pauld@redhat.com>
Link: https://lkml.kernel.org/r/20200513135502.4672-1-vincent.guittot@linaro.org

parent 9013196a

kernel/sched/fair.c

+19 −20

Original line number	Diff line number	Diff line
		@@ -5512,9 +5512,9 @@ enqueue_task_fair(struct rq rq, struct task_struct p, int flags)
		list_add_leaf_cfs_rq(cfs_rq);
		}

		enqueue_throttle:
		if (!se) {
		/* At this point se is NULL and we are at root level*/
		add_nr_running(rq, 1);

		/*
		* Since new tasks are assigned an initial util_avg equal to
		* half of the spare capacity of their CPU, tiny tasks have the
		@@ -5532,8 +5532,7 @@ enqueue_throttle:
		if (flags & ENQUEUE_WAKEUP)
		update_overutilized_status(rq);

		}

		enqueue_throttle:
		if (cfs_bandwidth_used()) {
		/*
		* When bandwidth control is enabled; the cfs_rq_throttled()