From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754879Ab0CXHH0 (ORCPT ); Wed, 24 Mar 2010 03:07:26 -0400 Received: from mailout2.zih.tu-dresden.de ([141.30.67.73]:49388 "EHLO mailout2.zih.tu-dresden.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752668Ab0CXHHY convert rfc822-to-8bit (ORCPT ); Wed, 24 Mar 2010 03:07:24 -0400 Subject: Re: [PATCH] trace power_frequency events on the correct cpu (for Intel x86 CPUs) From: Robert =?ISO-8859-1?Q?Sch=F6ne?= To: Arjan van de Ven Cc: Thomas Renninger , Dave Jones , Thomas Gleixner , Ingo Molnar , linux-kernel , cpufreq , x86@kernel.org In-Reply-To: <4BA8F34C.9040401@linux.intel.com> References: <1268399863.3407.15.camel@localhost> <4BA7773A.5080206@linux.intel.com> <1269361716.3475.1.camel@localhost> <201003231757.51259.trenn@suse.de> <4BA8F34C.9040401@linux.intel.com> Content-Type: text/plain; charset="UTF-8" Date: Wed, 24 Mar 2010 08:07:17 +0100 Message-ID: <1269414437.3355.6.camel@localhost> Mime-Version: 1.0 X-Mailer: Evolution 2.28.1 Content-Transfer-Encoding: 8BIT X-TUD-Virus-Scanned: mailout2.zih.tu-dresden.de Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Am Dienstag, den 23.03.2010, 09:58 -0700 schrieb Arjan van de Ven: > On 3/23/2010 9:57, Thomas Renninger wrote: > > On Tuesday 23 March 2010 17:28:36 Robert Schöne wrote: > >> Am Montag, den 22.03.2010, 06:57 -0700 schrieb Arjan van de Ven: > >>> On 3/22/2010 0:04, Robert Schöne wrote: > >>>> Am Sonntag, den 21.03.2010, 17:42 -0700 schrieb Arjan van de Ven: > >>>>> On 3/20/2010 14:37, Thomas Renninger wrote: > >>>>> > >>>>>> It also seem to be (hopefully) a minor feature for timechart, so this should > >>>>>> not hurt that much (yet). > >>>>> > >>>>> It's actually a major feature for timechart, and one of the key things I and a bunch of others > >>>>> inside Intel use timechart for. > >>>>> > >>>> It's a major feature for us too. > >>>> I suppose, the cpufreq_notify_transition calls are correct (meaning > >>>> being called for all related cpus) for every driver. So there's still > >>>> the option to include it in the POST_CHANGE section of this function. > >>>> Could this be okay for the both of you? > >>> > >>> post change would work... that gets frequency afaik.. > >> Are you ok with this too, Thomas? > > You mean hooking it into cpufreq_stat_notifier_trans() in > > drivers/cpufreq/cpufreq_stats.c? > > no > > > hooking into the post frequency change callback that gets done.. > which is guaranteed to be on the right cpu afaics. > I don't see where this would be guaranteed. So I'd be fine with a) adding it to cpufreq.c/cpufreq_notify_transition/cpufreq_notify_transition b) adding an item to the cpufreq_transition_notifier_list c) adding it to cpufreq_stats.c/cpufreq_stat_notifier_trans which would imply the usage of smp_call_function_single(...)