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From:   Josh Don <joshdon@google.com>
Date:   Tue, 9 Nov 2021 14:59:00 -0800
Message-ID: <CABk29NucnFxyPQ==n8-v=_hti2THkybrEkxruqJ_v8rvW4yacg@mail.gmail.com>
Subject: Re: [PATCH v2] sched/core: forced idle accounting
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>,
        Joel Fernandes <joel@joelfernandes.org>,
        Vineeth Pillai <vineethrp@gmail.com>,
        Hao Luo <haoluo@google.com>, Tao Zhou <tao.zhou@linux.dev>,
        linux-kernel@vger.kernel.org
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On Tue, Nov 9, 2021 at 3:15 AM Peter Zijlstra <peterz@infradead.org> wrote:
>
> On Mon, Oct 18, 2021 at 01:34:28PM -0700, Josh Don wrote:
> > @@ -5804,6 +5830,12 @@ pick_next_task(struct rq *rq, struct task_struct *prev, struct rq_flags *rf)
> >               }
> >       }
> >
> > +     if (rq->core->core_forceidle_count) {
>
> Does this want to be something like:
>
>         if (schedstat_enabled() && .. ) ?
>
> afaict without schedstat on this is dead code.
>

Makes sense to me, and similarly we can bail out of sched_core_tick()
early in the disabled case.