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 64C77C433F5 for ; Thu, 21 Apr 2022 06:26:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1384819AbiDUG3k (ORCPT ); Thu, 21 Apr 2022 02:29:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34822 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1384813AbiDUG3h (ORCPT ); Thu, 21 Apr 2022 02:29:37 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 8E7B513F26 for ; Wed, 20 Apr 2022 23:26:48 -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 E71BB1477; Wed, 20 Apr 2022 23:26:47 -0700 (PDT) Received: from [192.168.33.4] (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 8A9A93F73B; Wed, 20 Apr 2022 23:26:46 -0700 (PDT) Message-ID: <57119511-471e-8700-959b-4094e6bd1a76@arm.com> Date: Thu, 21 Apr 2022 07:26:36 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.7.0 Subject: Re: [PATCH] arch_topology: Trace the update thermal pressure Content-Language: en-US To: Steven Rostedt Cc: linux-kernel@vger.kernel.org, sudeep.holla@arm.com, dietmar.eggemann@arm.com, vincent.guittot@linaro.org, gregkh@linuxfoundation.org, rafael@kernel.org, mingo@redhat.com References: <20220419164801.29078-1-lukasz.luba@arm.com> <20220420194451.6b9661a0@gandalf.local.home> From: Lukasz Luba In-Reply-To: <20220420194451.6b9661a0@gandalf.local.home> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 4/21/22 00:44, Steven Rostedt wrote: > On Tue, 19 Apr 2022 17:48:01 +0100 > Lukasz Luba wrote: > >> diff --git a/drivers/base/arch_topology.c b/drivers/base/arch_topology.c >> index 1d6636ebaac5..4f0392de3081 100644 >> --- a/drivers/base/arch_topology.c >> +++ b/drivers/base/arch_topology.c >> @@ -19,6 +19,8 @@ >> #include >> #include >> >> +#include >> + >> static DEFINE_PER_CPU(struct scale_freq_data __rcu *, sft_data); >> static struct cpumask scale_freq_counters_mask; >> static bool scale_freq_invariant; >> @@ -195,6 +197,8 @@ void topology_update_thermal_pressure(const struct cpumask *cpus, >> >> th_pressure = max_capacity - capacity; >> >> + trace_thermal_pressure_update(cpu, th_pressure); >> + >> for_each_cpu(cpu, cpus) >> WRITE_ONCE(per_cpu(thermal_pressure, cpu), th_pressure); >> } >> diff --git a/include/trace/events/thermal.h b/include/trace/events/thermal.h >> index 8a5f04888abd..1bf08ee1a25b 100644 >> --- a/include/trace/events/thermal.h >> +++ b/include/trace/events/thermal.h >> @@ -65,6 +65,25 @@ TRACE_EVENT(cdev_update, >> TP_printk("type=%s target=%lu", __get_str(type), __entry->target) >> ); >> >> +TRACE_EVENT(thermal_pressure_update, >> + >> + TP_PROTO(int cpu, unsigned long thermal_pressure), >> + >> + TP_ARGS(cpu, thermal_pressure), >> + >> + TP_STRUCT__entry( >> + __field(int, cpu) >> + __field(unsigned long, thermal_pressure) > > Note, it is always best to place the bigger object before the smaller one > (when not properly aligned), as that will help to prevent structure > "holes". That is: > > __field(unsigned long, thermal_pressure) > __field(int, cpu) > > > Otherwise, you are pretty much guaranteed to have a 4 byte hole between cpu > and thermal_pressure on 64 bit machines. > > Also, for the warning you got from the test robot, if you are using this in > a module and defining it in the core kernel, you need to add: > > EXPORT_TRACEPOINT_SYMBOL_GPL(thermal_pressure_update); > > Somewhere in the C file that includes this file and defines > CREATE_TRACE_POINTS. > > -- Steve > > Thank you Steve, I'll swap those fields and add the needed export. I have to go through those older trace events in that file and understand if they are correct, since I just followed the pattern in 'cdev_update'. Regards, Lukasz