Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754482AbbEKPk2 (ORCPT ); Mon, 11 May 2015 11:40:28 -0400 Received: from mx1.redhat.com ([209.132.183.28]:34279 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752725AbbEKPkY (ORCPT ); Mon, 11 May 2015 11:40:24 -0400 Date: Mon, 11 May 2015 12:40:22 -0300 From: "Herton R. Krzesinski" To: Thomas Renninger Cc: "Rafael J. Wysocki" , linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] cpupower: mperf monitor: fix output in MAX_FREQ_SYSFS mode Message-ID: <20150511154022.GA3390@localhost.localdomain> References: <1431354935-7538-1-git-send-email-herton@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1431354935-7538-1-git-send-email-herton@redhat.com> User-Agent: Mutt/1.5.23.1-rc1 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3879 Lines: 84 On Mon, May 11, 2015 at 11:35:35AM -0300, Herton R. Krzesinski wrote: > There is clearly wrong output when mperf monitor runs in MAX_FREQ_SYSFS mode: > average frequency shows in kHz unit (despite the intended output to be in MHz), > and percentages for C state information are all wrong (including high/negative > values shown). > > The problem is that the max_frequency read on initialization isn't used where it > should have been used on mperf_get_count_percent (to estimate the number of > ticks in the given time period), and the value we read from sysfs is in kHz, so > we must divide it to get the MHz value to use in current calculations. > > While at it, also I fixed another small issues in the debug output of > max_frequency value in mperf_get_count_freq. > > Signed-off-by: Herton R. Krzesinski > --- > tools/power/cpupower/utils/idle_monitor/mperf_monitor.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) Actually please consider v2 patch below, just a minor change in the debug output, which isn't a percentage... From: "Herton R. Krzesinski" Date: Mon, 11 May 2015 11:18:14 -0300 Subject: [PATCH v2] cpupower: mperf monitor: fix output in MAX_FREQ_SYSFS mode There is clearly wrong output when mperf monitor runs in MAX_FREQ_SYSFS mode: average frequency shows in kHz unit (despite the intended output to be in MHz), and percentages for C state information are all wrong (including high/negative values shown). The problem is that the max_frequency read on initialization isn't used where it should have been used on mperf_get_count_percent (to estimate the number of ticks in the given time period), and the value we read from sysfs is in kHz, so we must divide it to get the MHz value to use in current calculations. While at it, also I fixed another small issues in the debug output of max_frequency value in mperf_get_count_freq. Signed-off-by: Herton R. Krzesinski --- tools/power/cpupower/utils/idle_monitor/mperf_monitor.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) v2: remove percent from debug output fix diff --git a/tools/power/cpupower/utils/idle_monitor/mperf_monitor.c b/tools/power/cpupower/utils/idle_monitor/mperf_monitor.c index 90a8c4f..c83f160 100644 --- a/tools/power/cpupower/utils/idle_monitor/mperf_monitor.c +++ b/tools/power/cpupower/utils/idle_monitor/mperf_monitor.c @@ -135,7 +135,7 @@ static int mperf_get_count_percent(unsigned int id, double *percent, dprint("%s: TSC Ref - mperf_diff: %llu, tsc_diff: %llu\n", mperf_cstates[id].name, mperf_diff, tsc_diff); } else if (max_freq_mode == MAX_FREQ_SYSFS) { - timediff = timespec_diff_us(time_start, time_end); + timediff = max_frequency * timespec_diff_us(time_start, time_end); *percent = 100.0 * mperf_diff / timediff; dprint("%s: MAXFREQ - mperf_diff: %llu, time_diff: %llu\n", mperf_cstates[id].name, mperf_diff, timediff); @@ -176,7 +176,7 @@ static int mperf_get_count_freq(unsigned int id, unsigned long long *count, dprint("%s: Average freq based on %s maximum frequency:\n", mperf_cstates[id].name, (max_freq_mode == MAX_FREQ_TSC_REF) ? "TSC calculated" : "sysfs read"); - dprint("%max_frequency: %lu", max_frequency); + dprint("max_frequency: %lu\n", max_frequency); dprint("aperf_diff: %llu\n", aperf_diff); dprint("mperf_diff: %llu\n", mperf_diff); dprint("avg freq: %llu\n", *count); @@ -279,6 +279,7 @@ use_sysfs: return -1; } max_freq_mode = MAX_FREQ_SYSFS; + max_frequency /= 1000; /* Default automatically to MHz value */ return 0; } -- 2.1.0 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/