Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752071Ab2KQOuh (ORCPT ); Sat, 17 Nov 2012 09:50:37 -0500 Received: from mail.skyhub.de ([78.46.96.112]:53638 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751850Ab2KQOub (ORCPT ); Sat, 17 Nov 2012 09:50:31 -0500 Date: Sat, 17 Nov 2012 15:50:48 +0100 From: Borislav Petkov To: Mark Langsdorf Cc: "linux-kernel@vger.kernel.org" , "cpufreq@vger.kernel.org" , "linux-pm@vger.kernel.org" , MyungJoo Ham Subject: Re: [PATCH 3/6 v4] cpufreq: tolerate inexact values when collecting stats Message-ID: <20121117145048.GI16441@x1.osrc.amd.com> Mail-Followup-To: Borislav Petkov , Mark Langsdorf , "linux-kernel@vger.kernel.org" , "cpufreq@vger.kernel.org" , "linux-pm@vger.kernel.org" , MyungJoo Ham References: <1351631056-25938-1-git-send-email-mark.langsdorf@calxeda.com> <1352313166-28980-1-git-send-email-mark.langsdorf@calxeda.com> <1352313166-28980-4-git-send-email-mark.langsdorf@calxeda.com> <20121111163821.GA21635@x1.osrc.amd.com> <50A12565.4070701@calxeda.com> <20121113162449.GE9327@x1.osrc.amd.com> <50A2766D.6040008@calxeda.com> <21672683C5A3814BB4DB938EBE482DE426EA988080@IAD2MBX09.mex02.mlsrvr.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <21672683C5A3814BB4DB938EBE482DE426EA988080@IAD2MBX09.mex02.mlsrvr.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1185 Lines: 29 On Tue, Nov 13, 2012 at 02:13:38PM -0500, Mark Langsdorf wrote: > Although cpufreq_driver has a flag field, no part of cpufreq_driver > is directly passed to the cpufreq_stat code. Only cpufreq_policy > is. It's cleaner to do passes of the while loop than to copy the > cpufreq_driver.flag field into cpufreq_policy and then store it again > in cpufreq_stats. That maybe so but this newly added loop which is only Calxeda-relevant is called in cpufreq_stat_notifier_trans, which is the frequency change notifier call, AFAICT. So each cpufreq driver will be paying that small and needless penalty now for nothing and on each frequency change. Which adds to the kernel-wide bloat and we absolutely don't want that. So you probably need to find a slick way of detecting calxeda hw somewhere along the init path of cpufreq_stats_init and set a hw-specific flag instead of adding that cost to each driver. Thanks. -- Regards/Gruss, Boris. -- 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/