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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B46B2C433EF for ; Mon, 25 Oct 2021 07:49:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 98ED860F22 for ; Mon, 25 Oct 2021 07:49:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231971AbhJYHwQ (ORCPT ); Mon, 25 Oct 2021 03:52:16 -0400 Received: from gateway31.websitewelcome.com ([192.185.144.97]:47603 "EHLO gateway31.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229723AbhJYHwO (ORCPT ); Mon, 25 Oct 2021 03:52:14 -0400 X-Greylist: delayed 1406 seconds by postgrey-1.27 at vger.kernel.org; Mon, 25 Oct 2021 03:52:14 EDT Received: from cm10.websitewelcome.com (cm10.websitewelcome.com [100.42.49.4]) by gateway31.websitewelcome.com (Postfix) with ESMTP id 9ADAC39432 for ; Mon, 25 Oct 2021 02:26:25 -0500 (CDT) Received: from gator4132.hostgator.com ([192.185.4.144]) by cmsmtp with SMTP id euNFmSkJ36dDyeuNFm3n15; Mon, 25 Oct 2021 02:26:25 -0500 X-Authority-Reason: nr=8 Received: from host-79-18-63-114.retail.telecomitalia.it ([79.18.63.114]:60726 helo=[10.0.0.35]) by gator4132.hostgator.com with esmtpsa (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (Exim 4.94.2) (envelope-from ) id 1meuNE-003kSD-Cc; Mon, 25 Oct 2021 02:26:24 -0500 Message-ID: Date: Mon, 25 Oct 2021 09:26:18 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.2.0 Subject: Re: [PATCH V4 01/19] trace/osnoise: Do not follow tracing_cpumask Content-Language: en-US To: Steven Rostedt Cc: Ingo Molnar , Tom Zanussi , Masami Hiramatsu , Juri Lelli , Clark Williams , John Kacur , Peter Zijlstra , Thomas Gleixner , Sebastian Andrzej Siewior , linux-rt-users@vger.kernel.org, linux-trace-devel@vger.kernel.org, linux-kernel@vger.kernel.org References: <20211022222301.32c2d869@rorschach.local.home> From: Daniel Bristot de Oliveira In-Reply-To: <20211022222301.32c2d869@rorschach.local.home> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - gator4132.hostgator.com X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - kernel.org X-BWhitelist: no X-Source-IP: 79.18.63.114 X-Source-L: No X-Exim-ID: 1meuNE-003kSD-Cc X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: host-79-18-63-114.retail.telecomitalia.it ([10.0.0.35]) [79.18.63.114]:60726 X-Source-Auth: kernel@bristot.me X-Email-Count: 1 X-Source-Cap: YnJpc3RvdG1lO2JyaXN0b3RtZTtnYXRvcjQxMzIuaG9zdGdhdG9yLmNvbQ== X-Local-Domain: no Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/23/21 04:23, Steven Rostedt wrote: > On Thu, 21 Oct 2021 14:56:39 +0200 > Daniel Bristot de Oliveira wrote: > >> In preparation to support multiple instances, decople the > > "decouple" > >> osnoise/timelat workload from instance specific tracing_cpumask. >> >> Different instances can have conflicing cpumasks, making osnoise > > "conflicting" > > May I suggest a spell check for your commit logs? ;-) Ooops, I will fix them. I use Grammarly on most of my texts, but sometimes I forget to re-check. >> workload management needlessly complex. Osnoise already have its >> global cpu mask. >> >> I also thought about using the first instance mask, but the >> "first" instance could be removed before the others. >> >> This also fixes the problem that changing the tracing_mask was not >> re-starting the trace. >> >> Cc: Steven Rostedt >> Cc: Ingo Molnar >> Cc: Tom Zanussi >> Cc: Masami Hiramatsu >> Cc: Juri Lelli >> Cc: Clark Williams >> Cc: John Kacur >> Cc: Peter Zijlstra >> Cc: Thomas Gleixner >> Cc: Sebastian Andrzej Siewior >> Cc: Daniel Bristot de Oliveira >> Cc: linux-rt-users@vger.kernel.org >> Cc: linux-trace-devel@vger.kernel.org >> Cc: linux-kernel@vger.kernel.org >> Signed-off-by: Daniel Bristot de Oliveira >> --- >> kernel/trace/trace_osnoise.c | 25 +++++++------------------ >> 1 file changed, 7 insertions(+), 18 deletions(-) >> >> diff --git a/kernel/trace/trace_osnoise.c b/kernel/trace/trace_osnoise.c >> index ce053619f289..7b1f8187764c 100644 >> --- a/kernel/trace/trace_osnoise.c >> +++ b/kernel/trace/trace_osnoise.c >> @@ -1553,13 +1553,10 @@ static int start_per_cpu_kthreads(struct trace_array *tr) >> >> cpus_read_lock(); >> /* >> - * Run only on CPUs in which trace and osnoise are allowed to run. >> + * Run only on online CPUs in which trace and osnoise are allowed to > > which trace and osnise? I thought we were removing "trace"? You are correct, I will remove the trace from the comment. Thanks! -- Daniel > -- Steve > >> + * run. >> */ >> - cpumask_and(current_mask, tr->tracing_cpumask, &osnoise_cpumask); >> - /* >> - * And the CPU is online. >> - */ >> - cpumask_and(current_mask, cpu_online_mask, current_mask); >> + cpumask_and(current_mask, cpu_online_mask, &osnoise_cpumask); >> >> for_each_possible_cpu(cpu) >> per_cpu(per_cpu_osnoise_var, cpu).kthread = NULL; >> @@ -1580,10 +1577,8 @@ static int start_per_cpu_kthreads(struct trace_array *tr) >> #ifdef CONFIG_HOTPLUG_CPU >> static void osnoise_hotplug_workfn(struct work_struct *dummy) >> { >> - struct trace_array *tr = osnoise_trace; >> unsigned int cpu = smp_processor_id(); >> >> - >> mutex_lock(&trace_types_lock); >> >> if (!osnoise_busy) >> @@ -1595,9 +1590,6 @@ static void osnoise_hotplug_workfn(struct work_struct *dummy) >> if (!cpumask_test_cpu(cpu, &osnoise_cpumask)) >> goto out_unlock; >> >> - if (!cpumask_test_cpu(cpu, tr->tracing_cpumask)) >> - goto out_unlock; >> - >> start_kthread(cpu); >> >> out_unlock: >> @@ -1700,13 +1692,10 @@ static void osnoise_tracer_stop(struct trace_array *tr); >> * interface to the osnoise trace. By default, it lists all CPUs, >> * in this way, allowing osnoise threads to run on any online CPU >> * of the system. It serves to restrict the execution of osnoise to the >> - * set of CPUs writing via this interface. Note that osnoise also >> - * respects the "tracing_cpumask." Hence, osnoise threads will run only >> - * on the set of CPUs allowed here AND on "tracing_cpumask." Why not >> - * have just "tracing_cpumask?" Because the user might be interested >> - * in tracing what is running on other CPUs. For instance, one might >> - * run osnoise in one HT CPU while observing what is running on the >> - * sibling HT CPU. >> + * set of CPUs writing via this interface. Why not use "tracing_cpumask"? >> + * Because the user might be interested in tracing what is running on >> + * other CPUs. For instance, one might run osnoise in one HT CPU >> + * while observing what is running on the sibling HT CPU. >> */ >> static ssize_t >> osnoise_cpus_write(struct file *filp, const char __user *ubuf, size_t count, >