From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D8074C38A2A for ; Fri, 8 May 2020 15:42:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B927121974 for ; Fri, 8 May 2020 15:42:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728365AbgEHPm1 (ORCPT ); Fri, 8 May 2020 11:42:27 -0400 Received: from elvis.franken.de ([193.175.24.41]:44985 "EHLO elvis.franken.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728282AbgEHPmZ (ORCPT ); Fri, 8 May 2020 11:42:25 -0400 Received: from uucp (helo=alpha) by elvis.franken.de with local-bsmtp (Exim 3.36 #1) id 1jX58n-0005J7-01; Fri, 08 May 2020 17:42:21 +0200 Received: by alpha.franken.de (Postfix, from userid 1000) id 65A77C043A; Fri, 8 May 2020 17:41:50 +0200 (CEST) Date: Fri, 8 May 2020 17:41:50 +0200 From: Thomas Bogendoerfer To: Sergey.Semin@baikalelectronics.ru Cc: Serge Semin , Alexey Malahov , Paul Burton , Ralf Baechle , Greg Kroah-Hartman , Arnd Bergmann , Rob Herring , linux-pm@vger.kernel.org, devicetree@vger.kernel.org, Vincenzo Frascino , Thomas Gleixner , linux-mips@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 18/20] mips: csrc-r4k: Decrease r4k-clocksource rating if CPU_FREQ enabled Message-ID: <20200508154150.GB22247@alpha.franken.de> References: <20200306124807.3596F80307C2@mail.baikalelectronics.ru> <20200506174238.15385-1-Sergey.Semin@baikalelectronics.ru> <20200506174238.15385-19-Sergey.Semin@baikalelectronics.ru> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200506174238.15385-19-Sergey.Semin@baikalelectronics.ru> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org On Wed, May 06, 2020 at 08:42:36PM +0300, Sergey.Semin@baikalelectronics.ru wrote: > From: Serge Semin > > Commit 07d69579e7fe ("MIPS: Don't register r4k sched clock when > CPUFREQ enabled") disabled the r4k-clock usage for scheduler ticks > counting due to the scheduler being non-tolerant for unstable > clocks sources. For the same reason the clock should be used > in the system clocksource framework only as a last resort if CPU > frequency may change. > > Signed-off-by: Serge Semin > Cc: Alexey Malahov > Cc: Thomas Bogendoerfer > Cc: Paul Burton > Cc: Ralf Baechle > Cc: Greg Kroah-Hartman > Cc: Arnd Bergmann > Cc: Rob Herring > Cc: linux-pm@vger.kernel.org > Cc: devicetree@vger.kernel.org > --- > arch/mips/kernel/csrc-r4k.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/arch/mips/kernel/csrc-r4k.c b/arch/mips/kernel/csrc-r4k.c > index 437dda64fd7a..d81fb374f477 100644 > --- a/arch/mips/kernel/csrc-r4k.c > +++ b/arch/mips/kernel/csrc-r4k.c > @@ -71,7 +71,11 @@ int __init init_r4k_clocksource(void) > return -ENXIO; > > /* Calculate a somewhat reasonable rating value */ > +#ifndef CONFIG_CPU_FREQ > clocksource_mips.rating = 200 + mips_hpt_frequency / 10000000; > +#else > + clocksource_mips.rating = 99; > +#endif I dislike this patch. Assuming you have an other clocksource, why not simply disable csrc-r4k, if CPU_FREQ is enabled ? Thomas. -- Crap can work. Given enough thrust pigs will fly, but it's not necessarily a good idea. [ RFC1925, 2.3 ]