From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754846AbdFXMDo (ORCPT ); Sat, 24 Jun 2017 08:03:44 -0400 Received: from mail-it0-f68.google.com ([209.85.214.68]:32814 "EHLO mail-it0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751276AbdFXMDm (ORCPT ); Sat, 24 Jun 2017 08:03:42 -0400 MIME-Version: 1.0 In-Reply-To: References: <1498281114-3868-1-git-send-email-lenb@kernel.org> <7c8784a63cdab6ff5ff7756060be6a77f5fe5915.1498280509.git.len.brown@intel.com> From: "Rafael J. Wysocki" Date: Sat, 24 Jun 2017 14:03:41 +0200 X-Google-Sender-Auth: cidJJrQ40lh96NL7Vzf6oa-nI4U Message-ID: Subject: Re: [PATCH 2/4 v2] x86: use common aperfmperf_khz_on_cpu() to calculate KHz using APERF/MPERF To: Thomas Gleixner Cc: Len Brown , "Rafael J. Wysocki" , "the arch/x86 maintainers" , Srinivas Pandruvada , Peter Zijlstra , Linux PM , Linux Kernel Mailing List , Len Brown Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Jun 24, 2017 at 10:56 AM, Thomas Gleixner wrote: > On Fri, 23 Jun 2017, Len Brown wrote: >> This x86 native method to calculate MHz returns a meaningful result >> no matter if P-states are controlled by hardware or firmware >> and/or if the Linux cpufreq sub-system is or is-not installed. >> >> When this routine is invoked more frequently, the measurement >> interval becomes shorter. However, the code limits re-computation >> to 10ms intervals so that average frequency remains meaningful. >> >> Discerning users are encouraged to take advantage of >> the turbostat(8) utility, which can gracefully handle >> concurrent measurement intervals of arbitrary length. >> >> Signed-off-by: Len Brown > > Reviewed-by: Thomas Gleixner > > Raphael, please take the whole lot through the cpufreq tree. I will, thanks! Rafael