From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753608AbcAVQ0Z (ORCPT ); Fri, 22 Jan 2016 11:26:25 -0500 Received: from mx1.redhat.com ([209.132.183.28]:52026 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751091AbcAVQ0V (ORCPT ); Fri, 22 Jan 2016 11:26:21 -0500 Message-ID: <56A25829.7000200@redhat.com> Date: Fri, 22 Jan 2016 11:26:17 -0500 From: Prarit Bhargava User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.7.0 MIME-Version: 1.0 To: Seiichi Ikarashi , linux-kernel@vger.kernel.org CC: "Rafael J. Wysocki" , Radivoje Jovanovic , Mathias Krause , Ajay Thomas Subject: Re: [PATCH 1/3] powercap, intel_rapl, implement get_max_time_window References: <1453392910-9549-1-git-send-email-prarit@redhat.com> <1453392910-9549-2-git-send-email-prarit@redhat.com> <56A1777F.6070809@jp.fujitsu.com> In-Reply-To: <56A1777F.6070809@jp.fujitsu.com> Content-Type: text/plain; charset=iso-2022-jp Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/21/2016 07:27 PM, Seiichi Ikarashi wrote: > On 2016-01-22 01:15, Prarit Bhargava wrote: >> The MSR_PKG_POWER_INFO register (Intel ASDM, section 14.9.3 >> "Package RAPL Domain") provides a maximum time window which the >> system can support. This window is read-only and is currently >> not examined when setting the time windows for the package. >> >> This patch implements get_max_time_window_us() and checks the window when >> a user attempts to set power capping for the package. >> >> Before the patch it was possible to set the window to, for example, 10000 >> micro seconds: >> >> [root@intel-chiefriver-03 rhel7]# echo 10000 > >> /sys/devices/virtual/powercap/intel-rapl/intel-rapl\:0/constraint_0_time_window_us; >> egrep ^ /sys/devices/virtual/powercap/intel-rapl/intel-rapl\:0/constraint_0_time_window_us >> >> /sys/devices/virtual/powercap/intel-rapl/intel-rapl:0/constraint_0_time_window_us:1:9765 >> >> but from 'turbostat -d', the package is limited to 976us: >> >> cpu0: MSR_PKG_POWER_INFO: 0x01200168 (45 W TDP, RAPL 36 - 0 W, 0.000977 sec.) >> >> (Note, there appears to be a rounding issue in turbostat which needs to >> also be fixed. Looking at the values in the register it is clear the >> value is 1/1024 = 976us.) >> >> After the patch we are limited by the maximum time window: >> >> [root@intel-chiefriver-03 rhel7]# echo 10000 > >> /sys/devices/virtual/powercap/intel-rapl/intel-rapl\:0/constraint_0_time_window_us; >> egrep ^ /sys/devices/virtual/powercap/intel-rapl/intel-rapl\:0/constraint_0_time_window_us >> >> -bash: echo: write error: Invalid argument >> /sys/devices/virtual/powercap/intel-rapl/intel-rapl:0/constraint_0_time_window_us:1:976 >> >> Cc: "Rafael J. Wysocki" >> Cc: Prarit Bhargava >> Cc: Radivoje Jovanovic >> Cc: Seiichi Ikarashi >> Cc: Mathias Krause >> Cc: Ajay Thomas >> Signed-off-by: Prarit Bhargava >> --- >> drivers/powercap/intel_rapl.c | 31 +++++++++++++++++++++++++++++++ >> drivers/powercap/powercap_sys.c | 6 ++++-- >> 2 files changed, 35 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/powercap/intel_rapl.c b/drivers/powercap/intel_rapl.c >> index cc97f08..f765b2c 100644 >> --- a/drivers/powercap/intel_rapl.c >> +++ b/drivers/powercap/intel_rapl.c >> @@ -493,13 +493,42 @@ static int get_current_power_limit(struct powercap_zone *power_zone, int id, >> return ret; >> } >> >> +static int get_max_time_window(struct powercap_zone *power_zone, int id, >> + u64 *data) > > The 2nd arg "id" is not necessary. It is required by the powercap_sys code. If I remove this then I have to create separate sysfs store and show files and I think it isn't worth it to do so. P. > > -- > Seiichi >