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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 40EBEEB64D8 for ; Tue, 20 Jun 2023 18:08:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229813AbjFTSID (ORCPT ); Tue, 20 Jun 2023 14:08:03 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49680 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229618AbjFTSIB (ORCPT ); Tue, 20 Jun 2023 14:08:01 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id C39DB198; Tue, 20 Jun 2023 11:07:59 -0700 (PDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 540291063; Tue, 20 Jun 2023 11:08:43 -0700 (PDT) Received: from [10.57.24.104] (unknown [10.57.24.104]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 983373F64C; Tue, 20 Jun 2023 11:07:55 -0700 (PDT) Message-ID: Date: Tue, 20 Jun 2023 19:08:12 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.11.0 Subject: Re: [RESEND][PATCH v2 3/3] schedutil: trace: Add tracing to capture filter out requests Content-Language: en-US To: "Rafael J. Wysocki" Cc: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-pm@vger.kernel.org, rostedt@goodmis.org, mhiramat@kernel.org, mingo@redhat.com, peterz@infradead.org, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, bsegall@google.com, mgorman@suse.de, bristot@redhat.com, vschneid@redhat.com, delyank@fb.com, qyousef@google.com, qyousef@layalina.io, kernel test robot References: <20230522145702.2419654-1-lukasz.luba@arm.com> <20230522145702.2419654-4-lukasz.luba@arm.com> From: Lukasz Luba In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Rafael, On 6/20/23 18:40, Rafael J. Wysocki wrote: > On Mon, May 22, 2023 at 4:57 PM Lukasz Luba wrote: >> >> Some of the frequency update requests coming form the task scheduler >> might be filter out. It can happen when the previous request was served >> not that long ago (in a period smaller than provided by the cpufreq driver >> as minimum for frequency update). In such case, we want to know if some of >> the frequency updates cannot make through. >> Export the new tracepoint as well. That would allow to handle it by a >> toolkit for trace analyzes. >> >> Reported-by: kernel test robot # solved tricky build >> Signed-off-by: Lukasz Luba >> --- >> include/trace/events/sched.h | 4 ++++ >> kernel/sched/cpufreq_schedutil.c | 10 ++++++++-- >> 2 files changed, 12 insertions(+), 2 deletions(-) >> >> diff --git a/include/trace/events/sched.h b/include/trace/events/sched.h >> index dbfb30809f15..e34b7cd5de73 100644 >> --- a/include/trace/events/sched.h >> +++ b/include/trace/events/sched.h >> @@ -739,6 +739,10 @@ DECLARE_TRACE(uclamp_update_tsk_tp, >> TP_PROTO(struct task_struct *tsk, int uclamp_id, unsigned int value), >> TP_ARGS(tsk, uclamp_id, value)); >> >> +DECLARE_TRACE(schedutil_update_filtered_tp, >> + TP_PROTO(int cpu), >> + TP_ARGS(cpu)); >> + >> #endif /* _TRACE_SCHED_H */ >> >> /* This part must be outside protection */ >> diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c >> index f462496e5c07..4f9daf258a65 100644 >> --- a/kernel/sched/cpufreq_schedutil.c >> +++ b/kernel/sched/cpufreq_schedutil.c >> @@ -6,6 +6,8 @@ >> * Author: Rafael J. Wysocki >> */ >> >> +EXPORT_TRACEPOINT_SYMBOL_GPL(schedutil_update_filtered_tp); >> + >> #define IOWAIT_BOOST_MIN (SCHED_CAPACITY_SCALE / 8) >> >> struct sugov_tunables { >> @@ -318,8 +320,10 @@ static inline bool sugov_update_single_common(struct sugov_cpu *sg_cpu, >> >> ignore_dl_rate_limit(sg_cpu); >> >> - if (!sugov_should_update_freq(sg_cpu->sg_policy, time)) >> + if (!sugov_should_update_freq(sg_cpu->sg_policy, time)) { >> + trace_schedutil_update_filtered_tp(sg_cpu->cpu); > > It looks like the tracepoint can be added to > sugov_should_update_freq() for less code duplication. > Make sense. I will move that trace there. In such case, of movement that trace call... Based on your comment for patch 2/3 I got impression that you still want it. For me it looks more 'aligned' w/ that patch 2/3. The two functions code flows: sugov_update_shared() and sugov_update_single_common() - how they call and interpret result from sugov_should_update_freq() - is more clear IMO. So I will keep that patch 2/3 in the next version. Although, if you don't like it - please tell me and I will drop it. Thanks for the review! Lukasz