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From:   Vincent Guittot <vincent.guittot@linaro.org>
Date:   Mon, 4 Dec 2023 10:54:28 +0100
Message-ID: <CAKfTPtBcF=sL6O17Vq-zCwqp48LNN46oTG=Drs5=MEh=gbuxPw@mail.gmail.com>
Subject: Re: [PATCH v2 2/2] sched/fair: Simplify util_est
To:     Qais Yousef <qyousef@layalina.io>
Cc:     mingo@redhat.com, peterz@infradead.org, juri.lelli@redhat.com,
        dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com,
        mgorman@suse.de, bristot@redhat.com, vschneid@redhat.com,
        corbet@lwn.net, alexs@kernel.org, siyanteng@loongson.cn,
        linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org,
        lukasz.luba@arm.com, hongyan.xia2@arm.com, yizhou.tang@shopee.com
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On Sun, 3 Dec 2023 at 00:38, Qais Yousef <qyousef@layalina.io> wrote:
>
> On 12/01/23 17:16, Vincent Guittot wrote:
>
> >  /*
> >   * The load/runnable/util_avg accumulates an infinite geometric series
> >   * (see __update_load_avg_cfs_rq() in kernel/sched/pelt.c).
> > @@ -505,9 +469,20 @@ struct sched_avg {
> >       unsigned long                   load_avg;
> >       unsigned long                   runnable_avg;
> >       unsigned long                   util_avg;
> > -     struct util_est                 util_est;
> > +     unsigned int                    util_est;
> >  } ____cacheline_aligned;
>
> unsigned long would be better?

I thought about changing it to unsigned long but I prefered to keep
using the same type as before for the ewma as we don't need to extend
it