From patchwork Thu Oct 28 21:29:32 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniel Bristot de Oliveira X-Patchwork-Id: 12591205 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 D0BC2C433EF for ; Thu, 28 Oct 2021 21:31:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B6B27610D2 for ; Thu, 28 Oct 2021 21:31:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231460AbhJ1Vdi convert rfc822-to-8bit (ORCPT ); Thu, 28 Oct 2021 17:33:38 -0400 Received: from us-smtp-delivery-44.mimecast.com ([205.139.111.44]:35415 "EHLO us-smtp-delivery-44.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231448AbhJ1Vdh (ORCPT ); Thu, 28 Oct 2021 17:33:37 -0400 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-462-dTAERRdPN7a2PwWPTdbjzQ-1; Thu, 28 Oct 2021 17:31:04 -0400 X-MC-Unique: dTAERRdPN7a2PwWPTdbjzQ-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 8D6981006AA3; Thu, 28 Oct 2021 21:31:02 +0000 (UTC) Received: from x1.com (unknown [10.22.32.36]) by smtp.corp.redhat.com (Postfix) with ESMTP id ED3C2100EBBE; Thu, 28 Oct 2021 21:30:58 +0000 (UTC) From: Daniel Bristot de Oliveira To: Steven Rostedt Cc: Daniel Bristot de Oliveira , 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 Subject: [PATCH V7 4/9] trace/osnoise: Use start/stop_per_cpu_kthreads() on osnoise_cpus_write() Date: Thu, 28 Oct 2021 23:29:32 +0200 Message-Id: <397b91c88953c079ba8e61aa040fe415fc0c91bc.1635452903.git.bristot@kernel.org> In-Reply-To: References: MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=bristot@kernel.org X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-trace-devel@vger.kernel.org When writing a new CPU mask via osnoise/cpus, if the tracer is running, the workload is restarted to follow the new cpumask. The restart is currently done using osnoise_workload_start/stop(), which disables the workload *and* the instrumentation. However, disabling the instrumentation is not necessary. Calling start/stop_per_cpu_kthreads() is enough to apply the new osnoise/cpus config. 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 | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/kernel/trace/trace_osnoise.c b/kernel/trace/trace_osnoise.c index 4381a06af916..7453b96c548b 100644 --- a/kernel/trace/trace_osnoise.c +++ b/kernel/trace/trace_osnoise.c @@ -1677,9 +1677,6 @@ osnoise_cpus_read(struct file *filp, char __user *ubuf, size_t count, return count; } -static int osnoise_workload_start(void); -static void osnoise_workload_stop(void); - /* * osnoise_cpus_write - Write function for "cpus" entry * @filp: The active open file structure @@ -1724,7 +1721,7 @@ osnoise_cpus_write(struct file *filp, const char __user *ubuf, size_t count, mutex_lock(&trace_types_lock); running = osnoise_busy; if (running) - osnoise_workload_stop(); + stop_per_cpu_kthreads(); mutex_lock(&interface_lock); /* @@ -1738,7 +1735,7 @@ osnoise_cpus_write(struct file *filp, const char __user *ubuf, size_t count, mutex_unlock(&interface_lock); if (running) - osnoise_workload_start(); + start_per_cpu_kthreads(); mutex_unlock(&trace_types_lock); free_cpumask_var(osnoise_cpumask_new);