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From:   Josh Don <joshdon@google.com>
Date:   Fri, 8 Oct 2021 14:04:00 -0700
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Subject: Re: [PATCH] sched/core: forced idle accounting
To:     Ingo Molnar <mingo@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Juri Lelli <juri.lelli@redhat.com>,
        Vincent Guittot <vincent.guittot@linaro.org>
Cc:     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>,
        Joel Fernandes <joel@joelfernandes.org>,
        Vineeth Pillai <vineethrp@gmail.com>,
        Hao Luo <haoluo@google.com>,
        linux-kernel <linux-kernel@vger.kernel.org>
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On Thu, Oct 7, 2021 at 5:08 PM Josh Don <joshdon@google.com> wrote:
>
> @@ -6051,6 +6071,13 @@ static void sched_core_cpu_deactivate(unsigned int cpu)
>         core_rq->core_forceidle     = rq->core_forceidle;
>         core_rq->core_forceidle_seq = rq->core_forceidle_seq;
>
> +       /*
> +        * Accounting edge for forced idle is handled in pick_next_task().
> +        * Don't need another one here, since the hotplug thread shouldn't
> +        * have a cookie.
> +        */
> +       core_rq->core_forceidle_start = 0;
> +
>         /* install new leader */
>         for_each_cpu(t, smt_mask) {
>                 rq = cpu_rq(t);

Realized there needs to be a similar edge in sched_core_flip(). I'll
include that in a v2, after seeing if there are any other comments on
this patch.