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Date:   Sun, 19 Jun 2022 01:54:25 +0800
From:   Huichun Feng <foxhoundsk.tw@gmail.com>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     Ingo Molnar <mingo@redhat.com>, Juri Lelli <juri.lelli@redhat.com>,
        Vincent Guittot <vincent.guittot@linaro.org>,
        Dietmar Eggemann <dietmar.eggemann@arm.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        Ben Segall <bsegall@google.com>, Mel Gorman <mgorman@suse.de>,
        Daniel Bristot de Oliveira <bristot@redhat.com>,
        Valentin Schneider <vschneid@redhat.com>,
        "open list:SCHEDULER" <linux-kernel@vger.kernel.org>,
        jserv@ccns.ncku.edu.tw, Chin-En Lin <shiyn.lin@gmail.com>
Subject: Re: [PATCH v2] sched/fair: avoid redundant hrtimer check
Message-ID: <20220618175425.GE10867@thinkpad>
References: <20220606122612.2580930-1-foxhoundsk.tw@gmail.com>
 <YqHnr8SA2gbf45ok@worktop.programming.kicks-ass.net>
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The check is required iff HRTICK is enabled and DOUBLE_TICK is disabled,
don't do that then.

Signed-off-by: Huichun Feng <foxhoundsk.tw@gmail.com>
---

Changes since v1:
- Refine commit message

 kernel/sched/fair.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 77b2048a9..80cc1a924 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -4668,7 +4668,7 @@ entity_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr, int queued)
        /*
         * don't let the period tick interfere with the hrtick preemption
         */
-       if (!sched_feat(DOUBLE_TICK) &&
+       if (sched_feat(HRTICK) && !sched_feat(DOUBLE_TICK) &&
                        hrtimer_active(&rq_of(cfs_rq)->hrtick_timer))
                return;
 #endif
-- 
2.36.1