From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.6 required=3.0 tests=DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,T_DKIM_INVALID autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A627EC5CFC1 for ; Tue, 19 Jun 2018 12:26:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4B2F120836 for ; Tue, 19 Jun 2018 12:26:57 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="qWZ0vyrA" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4B2F120836 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965953AbeFSM04 (ORCPT ); Tue, 19 Jun 2018 08:26:56 -0400 Received: from merlin.infradead.org ([205.233.59.134]:41534 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964997AbeFSM0y (ORCPT ); Tue, 19 Jun 2018 08:26:54 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=merlin.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=2t6iHGlO4Kxxws9kBydDEMiZ99HbO5lrqA94nOVFCac=; b=qWZ0vyrAA+p8jhGc2Ht0uj6nl T4e0UpSlLzaUCrzK7qWkeJQBQ8DwX9B2gN2pUkStLIrIAOoQT8U9jYlZtJjMNgZrBGKmUHemRJN1y jWi5ha7nTAhLN2pXWNNJp7iuMHI4m4R7dECIq8Cmn4Og/fBJVXjYev7vU2fcoe8hCu6mX/sR8ERaP xp4bgpPHeD0TD4+j2CFcBYnhO/50e43WuTY7IhAE10a4nPJ7Opc6ARb2iVHGL1fvSInEcmeQXrQS0 1ggmEaJasKfM+NTftXDbM7l6F4/BKxrBsC8tuB4CpqEFH1PVQ1V7uUXUJo0XU6t0V4p6nr89R0XoE 5VfRBS6TQ==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=hirez.programming.kicks-ass.net) by merlin.infradead.org with esmtpsa (Exim 4.90_1 #2 (Red Hat Linux)) id 1fVFiU-0000Zw-HK; Tue, 19 Jun 2018 12:26:35 +0000 Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 7BDD92029FA0E; Tue, 19 Jun 2018 14:26:32 +0200 (CEST) Date: Tue, 19 Jun 2018 14:26:32 +0200 From: Peter Zijlstra To: Quentin Perret Cc: rjw@rjwysocki.net, gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.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, joelaf@google.com, 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 Subject: Re: [RFC PATCH v3 05/10] sched/topology: Reference the Energy Model of CPUs when available Message-ID: <20180619122632.GS2458@hirez.programming.kicks-ass.net> References: <20180521142505.6522-1-quentin.perret@arm.com> <20180521142505.6522-6-quentin.perret@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180521142505.6522-6-quentin.perret@arm.com> User-Agent: Mutt/1.10.0 (2018-05-17) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, May 21, 2018 at 03:25:00PM +0100, Quentin Perret wrote: > In order to use EAS, the task scheduler has to know about the Energy > Model (EM) of the platform. This commit extends the scheduler topology > code to take references on the frequency domains objects of the EM > framework for all online CPUs. Hence, the availability of the EM for > those CPUs is guaranteed to the scheduler at runtime without further > checks in latency sensitive code paths (i.e. task wake-up). I'm confused by this patch,... what does it do? Why is em_cpu_get() (after you fix it) not sufficient?