Date: Tue, 21 Mar 2017 16:02:10 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Vincent Guittot <vincent.guittot@linaro.org>,
        Linux PM <linux-pm@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>,
        Viresh Kumar <viresh.kumar@linaro.org>,
        Juri Lelli <juri.lelli@arm.com>,
        Patrick Bellasi <patrick.bellasi@arm.com>,
        Joel Fernandes <joelaf@google.com>,
        Morten Rasmussen <morten.rasmussen@arm.com>,
        Ingo Molnar <mingo@redhat.com>
Subject: Re: [RFC][PATCH v2 2/2] cpufreq: schedutil: Avoid decreasing
 frequency of busy CPUs
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On Tue, Mar 21, 2017 at 03:26:06PM +0100, Rafael J. Wysocki wrote:
> +	if ((flags & SCHED_CPUFREQ_RT_DL) || this_rq()->rd->overload) {
>  		next_f = policy->cpuinfo.max_freq;

So this I think is wrong; rd->overload is set if _any_ of the CPUs in the
root domain is overloaded. And given the root domain is typically the
_entire_ machine, this would have a tendency to run at max_freq far too
often.