Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757582AbdCUPC3 (ORCPT ); Tue, 21 Mar 2017 11:02:29 -0400 Received: from bombadil.infradead.org ([65.50.211.133]:46367 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757522AbdCUPC0 (ORCPT ); Tue, 21 Mar 2017 11:02:26 -0400 Date: Tue, 21 Mar 2017 16:02:10 +0100 From: Peter Zijlstra To: "Rafael J. Wysocki" Cc: Vincent Guittot , Linux PM , LKML , Srinivas Pandruvada , Viresh Kumar , Juri Lelli , Patrick Bellasi , Joel Fernandes , Morten Rasmussen , Ingo Molnar Subject: Re: [RFC][PATCH v2 2/2] cpufreq: schedutil: Avoid decreasing frequency of busy CPUs Message-ID: <20170321150210.GT3093@worktop> References: <4366682.tsferJN35u@aspire.rjw.lan> <20170321132253.vjp7f72qkubpttmf@hirez.programming.kicks-ass.net> <3429350.K2FUBgvcIK@aspire.rjw.lan> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <3429350.K2FUBgvcIK@aspire.rjw.lan> User-Agent: Mutt/1.5.22.1 (2013-10-16) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 399 Lines: 8 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.