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=-7.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,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 8E6D8C433DF for ; Tue, 19 May 2020 01:50:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 740992065F for ; Tue, 19 May 2020 01:50:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726425AbgESBuL (ORCPT ); Mon, 18 May 2020 21:50:11 -0400 Received: from szxga07-in.huawei.com ([45.249.212.35]:49988 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726285AbgESBuL (ORCPT ); Mon, 18 May 2020 21:50:11 -0400 Received: from DGGEMS408-HUB.china.huawei.com (unknown [172.30.72.59]) by Forcepoint Email with ESMTP id 8ECD523AA1AC6E274294; Tue, 19 May 2020 09:50:08 +0800 (CST) Received: from [127.0.0.1] (10.166.215.101) by DGGEMS408-HUB.china.huawei.com (10.3.19.208) with Microsoft SMTP Server id 14.3.487.0; Tue, 19 May 2020 09:50:04 +0800 Subject: Re: [PATCH v2 20/20] cpufreq: Return zero on success in boost sw setting To: "Rafael J. Wysocki" , Serge Semin CC: Serge Semin , "Rafael J. Wysocki" , Viresh Kumar , "Rafael J. Wysocki" , Thomas Bogendoerfer , Ulf Hansson , "Matthias Kaehlcke" , Alexey Malahov , Paul Burton , Ralf Baechle , Arnd Bergmann , "Rob Herring" , , "devicetree@vger.kernel.org" , Stable , Frederic Weisbecker , "Ingo Molnar" , Yue Hu , Linux PM , Linux Kernel Mailing List References: <20200306124807.3596F80307C2@mail.baikalelectronics.ru> <20200518102415.k4c5qglodij5ac6h@vireshk-i7> <20200518103102.t3a3g4uxeeuwsnix@mobilestation> <5284478.EF2IWm2iUs@kreacher> <20200518104602.mjh2p5iltf2x4wmq@mobilestation> <20200518105649.gcv22l253lsuje7y@mobilestation> From: Xiongfeng Wang Message-ID: Date: Tue, 19 May 2020 09:50:03 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.4.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.166.215.101] X-CFilter-Loop: Reflected Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org Hi Rafael, On 2020/5/18 19:05, Rafael J. Wysocki wrote: > On Mon, May 18, 2020 at 12:56 PM Serge Semin > wrote: >> >> On Mon, May 18, 2020 at 12:51:15PM +0200, Rafael J. Wysocki wrote: >>> On Mon, May 18, 2020 at 12:46 PM Serge Semin >>> wrote: >>>> >>>> On Mon, May 18, 2020 at 12:41:19PM +0200, Rafael J. Wysocki wrote: >>>>> On Monday, May 18, 2020 12:31:02 PM CEST Serge Semin wrote: >>>>>> On Mon, May 18, 2020 at 03:54:15PM +0530, Viresh Kumar wrote: >>>>>>> On 18-05-20, 12:22, Rafael J. Wysocki wrote: >>>>>>>> On Monday, May 18, 2020 12:11:09 PM CEST Viresh Kumar wrote: >>>>>>>>> On 18-05-20, 11:53, Rafael J. Wysocki wrote: >>>>>>>>>> That said if you really only want it to return 0 on success, you may as well >>>>>>>>>> add a ret = 0; statement (with a comment explaining why it is needed) after >>>>>>>>>> the last break in the loop. >>>>>>>>> >>>>>>>>> That can be done as well, but will be a bit less efficient as the loop >>>>>>>>> will execute once for each policy, and so the statement will run >>>>>>>>> multiple times. Though it isn't going to add any significant latency >>>>>>>>> in the code. >>>>>>>> >>>>>>>> Right. >>>>>>>> >>>>>>>> However, the logic in this entire function looks somewhat less than >>>>>>>> straightforward to me, because it looks like it should return an >>>>>>>> error on the first policy without a frequency table (having a frequency >>>>>>>> table depends on the driver and that is the same for all policies, so it >>>>>>>> is pointless to iterate any further in that case). >>>>>>>> >>>>>>>> Also, the error should not be -EINVAL, because that means "invalid >>>>>>>> argument" which would be the state value. >>>>>>>> >>>>>>>> So I would do something like this: >>>>>>>> >>>>>>>> --- >>>>>>>> drivers/cpufreq/cpufreq.c | 11 ++++++----- >>>>>>>> 1 file changed, 6 insertions(+), 5 deletions(-) >>>>>>>> >>>>>>>> Index: linux-pm/drivers/cpufreq/cpufreq.c >>>>>>>> =================================================================== >>>>>>>> --- linux-pm.orig/drivers/cpufreq/cpufreq.c >>>>>>>> +++ linux-pm/drivers/cpufreq/cpufreq.c >>>>>>>> @@ -2535,26 +2535,27 @@ EXPORT_SYMBOL_GPL(cpufreq_update_limits) >>>>>>>> static int cpufreq_boost_set_sw(int state) >>>>>>>> { >>>>>>>> struct cpufreq_policy *policy; >>>>>>>> - int ret = -EINVAL; >>>>>>>> >>>>>>>> for_each_active_policy(policy) { >>>>>>>> + int ret; >>>>>>>> + >>>>>>>> if (!policy->freq_table) >>>>>>>> - continue; >>>>>>>> + return -ENXIO; >>>>>>>> >>>>>>>> ret = cpufreq_frequency_table_cpuinfo(policy, >>>>>>>> policy->freq_table); >>>>>>>> if (ret) { >>>>>>>> pr_err("%s: Policy frequency update failed\n", >>>>>>>> __func__); >>>>>>>> - break; >>>>>>>> + return ret; >>>>>>>> } >>>>>>>> >>>>>>>> ret = freq_qos_update_request(policy->max_freq_req, policy->max); >>>>>>>> if (ret < 0) >>>>>>>> - break; >>>>>>>> + return ret; >>>>>>>> } >>>>>>>> >>>>>>>> - return ret; >>>>>>>> + return 0; >>>>>>>> } >>>>>>>> >>>>>>>> int cpufreq_boost_trigger_state(int state) >>>>>>> >>>>>>> Acked-by: Viresh Kumar >>>>>> >>>>>> Ok. Thanks for the comments. Shall I resend the patch with update Rafael >>>>>> suggests or you'll merge the Rafael's fix in yourself? >>>>> >>>>> I'll apply the fix directly, thanks! >>>> >>>> Great. Is it going to be available in the repo: >>>> https://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm.git/ >>>> ? >>> >>> Yes, it is. Please see the bleeding-edge branch in there, thanks! Thanks for CCing me. I will write my next version based on this branch. Thanks, Xiongfeng >> >> No credits with at least Reported-by tag? That's sad.( > > OK, done now, but you are not the only reported of it, so I've added > the other reporter too. > > Thanks! > > . >