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=-5.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, 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 5227BC433DF for ; Fri, 22 May 2020 07:31:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 322B5206DD for ; Fri, 22 May 2020 07:31:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728959AbgEVHbY (ORCPT ); Fri, 22 May 2020 03:31:24 -0400 Received: from elvis.franken.de ([193.175.24.41]:34185 "EHLO elvis.franken.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728801AbgEVHbL (ORCPT ); Fri, 22 May 2020 03:31:11 -0400 Received: from uucp (helo=alpha) by elvis.franken.de with local-bsmtp (Exim 3.36 #1) id 1jc28x-0003HE-07; Fri, 22 May 2020 09:30:59 +0200 Received: by alpha.franken.de (Postfix, from userid 1000) id 29B17C015D; Fri, 22 May 2020 09:29:57 +0200 (CEST) Date: Fri, 22 May 2020 09:29:57 +0200 From: Thomas Bogendoerfer To: Serge Semin Cc: Serge Semin , Alexey Malahov , Paul Burton , Ralf Baechle , Greg Kroah-Hartman , Arnd Bergmann , Rob Herring , devicetree@vger.kernel.org, Jiaxun Yang , Alexander Lobakin , Huacai Chen , Vincenzo Frascino , Thomas Gleixner , linux-mips@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v4 12/13] mips: csrc-r4k: Mark R4K timer as unstable if CPU freq changes Message-ID: <20200522072957.GH7331@alpha.franken.de> References: <20200521140725.29571-1-Sergey.Semin@baikalelectronics.ru> <20200521140725.29571-13-Sergey.Semin@baikalelectronics.ru> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200521140725.29571-13-Sergey.Semin@baikalelectronics.ru> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-mips-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org On Thu, May 21, 2020 at 05:07:23PM +0300, Serge Semin wrote: > 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 > with care. As soon as CPU frequency changes the clocksource framework > should be notified about this by marking the R4K timer being unstable > (which it really is, since the ticks rate has been changed synchronously > with the CPU frequency). > > 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: devicetree@vger.kernel.org > --- > arch/mips/Kconfig | 1 + > arch/mips/kernel/csrc-r4k.c | 40 +++++++++++++++++++++++++++++++++++++ > 2 files changed, 41 insertions(+) applied to mips-next. Thomas. -- Crap can work. Given enough thrust pigs will fly, but it's not necessarily a good idea. [ RFC1925, 2.3 ]