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=-4.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED autolearn=no 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 3B81BC4363A for ; Mon, 5 Oct 2020 13:25:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EE02C207BC for ; Mon, 5 Oct 2020 13:25:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601904347; bh=47wn8D+fQC0Zg3ZtDB63fXO/tKbB4+/zklOIxCald7U=; h=References:In-Reply-To:From:Date:Subject:To:Cc:List-ID:From; b=hR3KoC+hbaXEeSot8y08cSr+myTtNeph8wprMHtezWXRtTTUcTZHnDXA0ol33Xg+P YnduPgAwa8P7zdrGTMVyRTjszKCxW8yr9Ijv3bRX7XFjruMDOKa9seO1UA2z08eCdJ cREA6IaVvzOtxyF1q/IsQJz60+jgMDCxJiApLYAE= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725931AbgJENZm (ORCPT ); Mon, 5 Oct 2020 09:25:42 -0400 Received: from mail-ot1-f68.google.com ([209.85.210.68]:36225 "EHLO mail-ot1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725914AbgJENZm (ORCPT ); Mon, 5 Oct 2020 09:25:42 -0400 Received: by mail-ot1-f68.google.com with SMTP id 60so8564019otw.3; Mon, 05 Oct 2020 06:25:40 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=VSm7gLjvoXVPW4MRbVep3VxyatFylcoxKzzruY+rFmA=; b=InZFc1lYgCZygfhHYk2b4a3MLtsjfM/Kj6YzSOPfbBArMSXZ3yAV/CZ3yH87Amlj29 9frevE4Yn+Qmx5ldJq1EXqajAaHGNioDWg23yirns3JRk7jCse+ix9S//CwAj8kEFN+Q /5nZfSaD8nkQrf+CuY9TabrfbOGHCYVpWBrU2PUYc4ewODK1Mk/lu9C5OzuTWJ0fww2r 8BR7fMBjWeoz11Z+cfB/SruBkKF+bS+ji+szgp9BFvrNMEDvVnAO90+xYle8Bqkbe8Bi JBeJeKnCncCQExaR441NUNrQ/WrrKuF92R8EDnIyuqQ48sjzLtdX9LESwBb4Ifqlsip5 oYqA== X-Gm-Message-State: AOAM5329Fia7b/0RdgHWfoKbh+Me13zr47U03PnuHxHPq4VhGJAXCiku Kb/pfhP1SbLgzNk4mvM2I6PyGuaobxnfXITkyj0= X-Google-Smtp-Source: ABdhPJzAhOvM/7gBRkLIamiQt5pp03piG1poAEdBabDBErML+QILbGXZKNRPjGnxftmzHcZgGjAR9Ak294uciO60TmU= X-Received: by 2002:a9d:734f:: with SMTP id l15mr5055320otk.260.1601904339903; Mon, 05 Oct 2020 06:25:39 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: From: "Rafael J. Wysocki" Date: Mon, 5 Oct 2020 15:25:28 +0200 Message-ID: Subject: Re: [PATCH V3 0/5] cpufreq: Record stats with fast-switching To: Viresh Kumar Cc: Rafael Wysocki , Ben Segall , Dietmar Eggemann , Ingo Molnar , Juri Lelli , Mel Gorman , Peter Zijlstra , Steven Rostedt , Vincent Guittot , Linux PM , Lukasz Luba , cristian.marussi@arm.com, Sudeep Holla , Linux Kernel Mailing List Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org On Mon, Oct 5, 2020 at 9:56 AM Viresh Kumar wrote: > > Hi, > > We disabled recording cpufreq stats when fast switching was introduced > to the cpufreq core as the cpufreq stats required to take a spinlock and > that can't be allowed (for performance reasons) on scheduler's hot path. > > Here is an attempt to get rid of the lock and bring back the support. > > V2->V3: > - Use READ/WRITE_ONCE() for reset-time as well. > - Use unlikely for few conditionals in the hot path. > - Better changelogs. > - Rebase changes. > > V1-V2: > - Use READ_ONCE/WRITE_ONCE instead of atomic in the first patch. > > -- > Viresh > > Viresh Kumar (5): > cpufreq: stats: Defer stats update to > cpufreq_stats_record_transition() > cpufreq: stats: Remove locking > cpufreq: stats: Mark few conditionals with unlikely() > cpufreq: stats: Enable stats for fast-switch as well > cpufreq: Move traces and update to policy->cur to cpufreq core > > drivers/cpufreq/cpufreq.c | 11 ++++ > drivers/cpufreq/cpufreq_stats.c | 89 ++++++++++++++++++++------------ > kernel/sched/cpufreq_schedutil.c | 12 +---- > 3 files changed, 69 insertions(+), 43 deletions(-) > > -- The entire series applied as 5.10 material with some minor changelog edits in patch [1/5], thanks!