linux-kernel - [RFC 13/60] sched: Remove useless checks for root task-group

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Message-Id: <20180907214047.26914-14-jschoenh@amazon.de>
Date:   Fri,  7 Sep 2018 23:40:00 +0200
From:   Jan H. Schönherr <jschoenh@...zon.de>
To:     Ingo Molnar <mingo@...hat.com>,
        Peter Zijlstra <peterz@...radead.org>
Cc:     Jan H. Schönherr <jschoenh@...zon.de>,
        linux-kernel@...r.kernel.org
Subject: [RFC 13/60] sched: Remove useless checks for root task-group

The functions sync_throttle() and unregister_fair_sched_group() are
called during the creation and destruction of cgroups. They are never
called for the root task-group. Remove checks that always yield the
same result when operating on non-root task groups.

Signed-off-by: Jan H. Schönherr <jschoenh@...zon.de>
---
 kernel/sched/fair.c | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 5d6225aedbfe..5cad364e3a88 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -4716,9 +4716,6 @@ static void sync_throttle(struct task_group *tg, int cpu)
 	if (!cfs_bandwidth_used())
 		return;
 
-	if (!tg->parent)
-		return;
-
 	cfs_rq = tg->cfs_rq[cpu];
 	pcfs_rq = tg->parent->cfs_rq[cpu];
 
@@ -9881,8 +9878,7 @@ void unregister_fair_sched_group(struct task_group *tg)
 	int cpu;
 
 	for_each_possible_cpu(cpu) {
-		if (tg->cfs_rq[cpu]->my_se)
-			remove_entity_load_avg(tg->cfs_rq[cpu]->my_se);
+		remove_entity_load_avg(tg->cfs_rq[cpu]->my_se);
 
 		/*
 		 * Only empty task groups can be destroyed; so we can speculatively
-- 
2.9.3.1.gcba166c.dirty