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From:   Dietmar Eggemann <dietmar.eggemann@arm.com>
Subject: Re: [PATCH v2 3/9] sched: Remove checks against SD_LOAD_BALANCE
To:     Valentin Schneider <valentin.schneider@arm.com>,
        linux-kernel@vger.kernel.org
Cc:     mingo@kernel.org, peterz@infradead.org, vincent.guittot@linaro.org
References: <20200311181601.18314-1-valentin.schneider@arm.com>
 <20200311181601.18314-4-valentin.schneider@arm.com>
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Date:   Thu, 19 Mar 2020 11:28:37 +0100
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On 11.03.20 19:15, Valentin Schneider wrote:
> Potential users of that flag could have been cpusets and isolcpus.
> 
> cpusets don't need it because they define exclusive (i.e. non-overlapping)
> domain spans, see cpuset.cpu_exclusive and cpuset.sched_load_balance.
> If such a cpuset contains a single CPU, it will have the NULL domain
> attached to it. If it contains several CPUs, none of their domains will
> extend beyond the span of the cpuset.

There are also non-exclusive cpusets but I assume the statement is the same.

CPUs which are only used in cpusets with cpuset.sched_load_balance=0 are
attached to the NULL sched-domain.

There seems to be no code which alters the SD_LOAD_BALANCE flag.

[...]