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From:   Odin Ugedal <odin@uged.al>
Date:   Wed, 23 Jun 2021 14:37:14 +0200
Message-ID: <CAFpoUr3bHzrwvumw6R=2JVbKa_wmtT9cMf-mdDHxY0Png-N9Jw@mail.gmail.com>
Subject: Re: [powerpc][next-20210621] WARNING at kernel/sched/fair.c:3277
 during boot
To:     Vincent Guittot <vincent.guittot@linaro.org>
Cc:     Odin Ugedal <odin@uged.al>,
        Sachin Sant <sachinp@linux.vnet.ibm.com>,
        Linux Next Mailing List <linux-next@vger.kernel.org>,
        linuxppc-dev@lists.ozlabs.org,
        open list <linux-kernel@vger.kernel.org>
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ons. 23. jun. 2021 kl. 14:22 skrev Vincent Guittot <vincent.guittot@linaro.org>:
>
> In theory it should not because _sum should be always larger or equal
> to _avg * divider. Otherwise, it means that we have something wrong
> somewhere else

Yeah, that might be the case. Still trying to wrap my head around
this. I might be wrong, but isn't there a possibility
that avg->period_contrib is increasing in PELTs accumulate_sum,
without _sum is increasing. This makes the pelt divider increase,
making the statement "_sum should be always larger or equal to _avg *"
false? Or am I missing something obvious here?

Still unable to reproduce what Sachin is reporting tho.

Odin