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Date:   Mon, 3 Jul 2023 14:10:09 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Phil Auld <pauld@redhat.com>
Cc:     linux-kernel@vger.kernel.org, Juri Lelli <juri.lelli@redhat.com>,
        Ingo Molnar <mingo@redhat.com>,
        Daniel Bristot de Oliveira <bristot@redhat.com>,
        Vincent Guittot <vincent.guittot@linaro.org>,
        Dietmar Eggemann <dietmar.eggemann@arm.com>,
        Valentin Schneider <vschneid@redhat.com>,
        Ben Segall <bsegall@google.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        Mel Gorman <mgorman@suse.de>,
        Frederic Weisbecker <frederic@kernel.org>
Subject: Re: [PATCH v4] Sched/fair: Block nohz tick_stop when cfs bandwidth
 in use
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On Fri, Jun 30, 2023 at 12:29:10PM -0400, Phil Auld wrote:

> I think you are agreeing that I need the pick next code but need to remove
> the hierarchy walks, right?

Yeah, the dequeue case makes we have to care about pick, not sure we
then also need to care about sched_update_tick_dependency() though.
There is indeed a window where these two will 'race', but afaict it is
benign.