From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Zijlstra Subject: Re: [RFC PATCH v4 09/12] sched/fair: Introduce an energy estimation helper function Date: Fri, 6 Jul 2018 17:50:56 +0200 Message-ID: <20180706155056.GP2494@hirez.programming.kicks-ass.net> References: <20180628114043.24724-1-quentin.perret@arm.com> <20180628114043.24724-10-quentin.perret@arm.com> <20180706131243.GV2458@hirez.programming.kicks-ass.net> <20180706151212.GD17577@e108498-lin.cambridge.arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20180706151212.GD17577@e108498-lin.cambridge.arm.com> Sender: linux-kernel-owner@vger.kernel.org To: Quentin Perret Cc: rjw@rjwysocki.net, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, gregkh@linuxfoundation.org, mingo@redhat.com, dietmar.eggemann@arm.com, morten.rasmussen@arm.com, chris.redpath@arm.com, patrick.bellasi@arm.com, valentin.schneider@arm.com, vincent.guittot@linaro.org, thara.gopinath@linaro.org, viresh.kumar@linaro.org, tkjos@google.com, joel@joelfernandes.org, smuckle@google.com, adharmap@quicinc.com, skannan@quicinc.com, pkondeti@codeaurora.org, juri.lelli@redhat.com, edubezval@gmail.com, srinivas.pandruvada@linux.intel.com, currojerez@riseup.net, javi.merino@kernel.org List-Id: linux-pm@vger.kernel.org On Fri, Jul 06, 2018 at 04:12:12PM +0100, Quentin Perret wrote: > I guess it is also worth mentioning that in the case mentioned above the > scheduling decisions made inside one root domain can indirectly be > impacted by the scheduling decisions made in another root domain. Some > CPUs inside one root domain might look expensive to use simply because > they run at a high OPP because of other CPUs of the same FD being > over-used in another root domain. That's simply how it is. There's nothing you can do about it, they share a clock, teh end.