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Date:   Mon, 7 Dec 2020 16:50:15 +0100
From:   Peter Zijlstra <peterz@infradead.org>
To:     Aubrey Li <aubrey.li@linux.intel.com>
Cc:     mingo@redhat.com, juri.lelli@redhat.com,
        vincent.guittot@linaro.org, mgorman@techsingularity.net,
        valentin.schneider@arm.com, qais.yousef@arm.com,
        dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com,
        tim.c.chen@linux.intel.com, linux-kernel@vger.kernel.org,
        Mel Gorman <mgorman@suse.de>, Jiang Biao <benbjiang@gmail.com>
Subject: Re: [RFC PATCH v5] sched/fair: select idle cpu from idle cpumask for
 task wakeup
Message-ID: <20201207155015.GQ3040@hirez.programming.kicks-ass.net>
References: <20201118043113.53128-1-aubrey.li@linux.intel.com>
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On Wed, Nov 18, 2020 at 12:31:13PM +0800, Aubrey Li wrote:
> Add idle cpumask to track idle cpus in sched domain. When a CPU
> enters idle, if the idle driver indicates to stop tick, this CPU
> is set in the idle cpumask to be a wakeup target. And if the CPU
> is not in idle, the CPU is cleared in idle cpumask during scheduler
> tick to ratelimit idle cpumask update.

So this will only have SIS consider CPUs that have the tick stopped?
That might affect the facebook tail-latency workloads quite a bit.