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=-7.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_2 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 F0C83C352AA for ; Wed, 2 Oct 2019 12:20:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CD93121920 for ; Wed, 2 Oct 2019 12:20:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727321AbfJBMU1 (ORCPT ); Wed, 2 Oct 2019 08:20:27 -0400 Received: from mx2.suse.de ([195.135.220.15]:54036 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727121AbfJBMUZ (ORCPT ); Wed, 2 Oct 2019 08:20:25 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id E6591AD09; Wed, 2 Oct 2019 12:20:22 +0000 (UTC) Message-ID: <1570019152.22393.0.camel@suse.cz> Subject: Re: [PATCH 1/2] x86,sched: Add support for frequency invariance From: Giovanni Gherdovich To: Peter Zijlstra Cc: srinivas.pandruvada@linux.intel.com, tglx@linutronix.de, mingo@redhat.com, bp@suse.de, lenb@kernel.org, rjw@rjwysocki.net, x86@kernel.org, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, mgorman@techsingularity.net, matt@codeblueprint.co.uk, viresh.kumar@linaro.org, juri.lelli@redhat.com, pjt@google.com, vincent.guittot@linaro.org, qperret@qperret.net, dietmar.eggemann@arm.com Date: Wed, 02 Oct 2019 14:25:52 +0200 In-Reply-To: <20190924163053.GA4519@hirez.programming.kicks-ass.net> References: <20190909024216.5942-1-ggherdovich@suse.cz> <20190909024216.5942-2-ggherdovich@suse.cz> <20190924163053.GA4519@hirez.programming.kicks-ass.net> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.26.6 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello Peter, late replies as I wasn't in the office last week. On Tue, 2019-09-24 at 18:30 +0200, Peter Zijlstra wrote: > On Mon, Sep 09, 2019 at 04:42:15AM +0200, Giovanni Gherdovich wrote: > > +static const struct x86_cpu_id has_turbo_ratio_group_limits[] = { > > + ICPU(INTEL_FAM6_ATOM_GOLDMONT), > > + ICPU(INTEL_FAM6_ATOM_GOLDMONT_X), > > That's GOLDMONT_D in recent tip kernels. Right, I saw that now. > > > + ICPU(INTEL_FAM6_ATOM_GOLDMONT_PLUS), > > + ICPU(INTEL_FAM6_SKYLAKE_X), > > What about KABYLAKE_X and ICELAKE_X ? KABYLAKE_X: does it exist? I couldn't find it in arch/x86/include/asm/intel-family.h (the tip tree), I only see KABYLAKE_L and KABYLAKE. ICELAKE_X: well, I don't know really. Does this model have the same semantic for MSR_TURBO_RATIO_LIMIT as SKYLAKE_X (which is family = 0x6, model = 0x55)? This is for Len B. and Srinivas P. (in CC). The latest Software Developer's Manual (SDM) from May 2019 (volume 4, section 2.17.3, "MSRs Specific to Intel Xeon Processor Scalable Family") mentions only "CPUID DisplayFamily_DisplayModel = 06_55H", which is SKYLAKE_X, as having the semantic I'm looking for here (in addition to Atom Goldmont's). The semantic I'm referring to is that MSR_TURBO_RATIO_LIMIT doesn't contain turbo levels for the fixed group sizes 1-2-3-4-... cores, the group sizes are specified in a different MSR (and could be 2-4-8-12-... for example). If the SDM is outdated and ICELAKE_X is also in that category, then the turbostat source code is outdated too as it has this function to detect this feature: int has_turbo_ratio_group_limits(int family, int model) { if (!genuine_intel) return 0; switch (model) { case INTEL_FAM6_ATOM_GOLDMONT: case INTEL_FAM6_SKYLAKE_X: case INTEL_FAM6_ATOM_GOLDMONT_X: return 1; } return 0; } (from the tree lenb/linux.git, branch "turbostat", turbostat version 19.08.31 not yet merged into mainline) Giovanni