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=-11.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 C10F5C433E0 for ; Tue, 16 Jun 2020 12:22:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A4FA321501 for ; Tue, 16 Jun 2020 12:22:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729192AbgFPMWm (ORCPT ); Tue, 16 Jun 2020 08:22:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42736 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728982AbgFPMWK (ORCPT ); Tue, 16 Jun 2020 08:22:10 -0400 Received: from Galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C82C2C08C5C3; Tue, 16 Jun 2020 05:22:09 -0700 (PDT) Received: from [5.158.153.53] (helo=tip-bot2.lab.linutronix.de) by Galois.linutronix.de with esmtpsa (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1jlAbL-0004kF-OK; Tue, 16 Jun 2020 14:22:03 +0200 Received: from [127.0.1.1] (localhost [IPv6:::1]) by tip-bot2.lab.linutronix.de (Postfix) with ESMTP id E65ED1C0095; Tue, 16 Jun 2020 14:21:54 +0200 (CEST) Date: Tue, 16 Jun 2020 12:21:54 -0000 From: "tip-bot2 for Giovanni Gherdovich" Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: sched/core] x86, sched: Bail out of frequency invariance if turbo frequency is unknown Cc: Ricardo Neri , Giovanni Gherdovich , "Peter Zijlstra (Intel)" , "Rafael J. Wysocki" , x86 , LKML In-Reply-To: <20200531182453.15254-3-ggherdovich@suse.cz> References: <20200531182453.15254-3-ggherdovich@suse.cz> MIME-Version: 1.0 Message-ID: <159231011472.16989.10542283129872543886.tip-bot2@tip-bot2> X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following commit has been merged into the sched/core branch of tip: Commit-ID: 51beea8862a3095559862df39554f05042e1195b Gitweb: https://git.kernel.org/tip/51beea8862a3095559862df39554f05042e1195b Author: Giovanni Gherdovich AuthorDate: Sun, 31 May 2020 20:24:52 +02:00 Committer: Peter Zijlstra CommitterDate: Mon, 15 Jun 2020 14:10:02 +02:00 x86, sched: Bail out of frequency invariance if turbo frequency is unknown There may be CPUs that support turbo boost but don't declare any turbo ratio, i.e. their MSR_TURBO_RATIO_LIMIT is all zeroes. In that condition scale-invariant calculations can't be performed. Fixes: 1567c3e3467c ("x86, sched: Add support for frequency invariance") Suggested-by: Ricardo Neri Signed-off-by: Giovanni Gherdovich Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Rafael J. Wysocki Tested-by: Ricardo Neri Link: https://lkml.kernel.org/r/20200531182453.15254-3-ggherdovich@suse.cz --- arch/x86/kernel/smpboot.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c index 18d292f..20e1cea 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -2002,9 +2002,11 @@ out: /* * Some hypervisors advertise X86_FEATURE_APERFMPERF * but then fill all MSR's with zeroes. + * Some CPUs have turbo boost but don't declare any turbo ratio + * in MSR_TURBO_RATIO_LIMIT. */ - if (!base_freq) { - pr_debug("Couldn't determine cpu base frequency, necessary for scale-invariant accounting.\n"); + if (!base_freq || !turbo_freq) { + pr_debug("Couldn't determine cpu base or turbo frequency, necessary for scale-invariant accounting.\n"); return false; }