From patchwork Fri Sep 17 15:44:00 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: 12502693 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=-14.0 required=3.0 tests=BAYES_00,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 2D28CC433EF for ; Fri, 17 Sep 2021 15:47:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 178896124B for ; Fri, 17 Sep 2021 15:47:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344264AbhIQPst convert rfc822-to-8bit (ORCPT ); Fri, 17 Sep 2021 11:48:49 -0400 Received: from us-smtp-delivery-44.mimecast.com ([205.139.111.44]:25743 "EHLO us-smtp-delivery-44.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344007AbhIQPsK (ORCPT ); Fri, 17 Sep 2021 11:48:10 -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-400-XfPfTbYgPV6f6UjE3dFVLg-1; Fri, 17 Sep 2021 11:46:45 -0400 X-MC-Unique: XfPfTbYgPV6f6UjE3dFVLg-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 5D663101AFA7; Fri, 17 Sep 2021 15:46:43 +0000 (UTC) Received: from x1.bristot.me.homenet.telecomitalia.it (unknown [10.22.17.200]) by smtp.corp.redhat.com (Postfix) with ESMTP id 959995D9C6; Fri, 17 Sep 2021 15:46:40 +0000 (UTC) From: Daniel Bristot de Oliveira To: Steven Rostedt Cc: Jonathan Corbet , Kate Carcia , Daniel Bristot de Oliveira , Ingo Molnar , Tom Zanussi , Masami Hiramatsu , Juri Lelli , Clark Williams , 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: [RFC 17/19] rtla: Add rtla timerlat documentation Date: Fri, 17 Sep 2021 17:44:00 +0200 Message-Id: <73e807efe17b1fb736c6771bbfc3881c11c4dadd.1631889858.git.bristot@kernel.org> In-Reply-To: References: MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 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 Man page for rtla timerlat tool. Cc: Steven Rostedt Cc: Ingo Molnar Cc: Tom Zanussi Cc: Masami Hiramatsu Cc: Juri Lelli Cc: Clark Williams 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 --- .../rtla/Documentation/rtla-timerlat.txt | 65 +++++++++++++++++++ 1 file changed, 65 insertions(+) create mode 100644 tools/tracing/rtla/Documentation/rtla-timerlat.txt diff --git a/tools/tracing/rtla/Documentation/rtla-timerlat.txt b/tools/tracing/rtla/Documentation/rtla-timerlat.txt new file mode 100644 index 000000000000..2b5ef9a9d6b0 --- /dev/null +++ b/tools/tracing/rtla/Documentation/rtla-timerlat.txt @@ -0,0 +1,65 @@ +rtla-timerlat(1) +================ + +NAME +---- +rtla-timerlat - Measures the operating system timer latency + +SYNOPSIS +-------- +*rtla timerlat* [MODE] ... + +DESCRIPTION +----------- +The rtla-timerlat(1) tool is an interface for the timerlat tracer. The +timerlat tracer dispatches a kernel thread per-cpu. These threads set +a periodic timer to wake themselves up and go back to sleep. After the +wakeup, they collect and generate useful information for the debugging +of operating system timer latency. + +The timerlat tracer outputs information in two ways. It periodically +prints the timer latency at the timer 'IRQ' handler and the 'Thread' handler. +It also provides information for each noise via the osnoise tracepoints. +The rtla-timerlat-top(1) mode displays a summary of the periodic output +from the timerlat tracer. The rtla-hist-hist(1) mode displays a histogram of +each tracer event occurrence. For further details, please refer to the +respective man page. + +MODES +----- +*top*:: + Prints the summary from timerlat tracer. +*hist*:: + Prints a histogram of timerlat samples. + +If no MODE is given, the top mode is called, passing the arguments. + +OPTIONS +------- +*-h*, *--help*:: + Display the help text. + +For other options, see the man page for the corresponding mode. + +SEE ALSO +-------- +_rtla-timerlat-top(1)_, _rtla-timerlat-hist(1)_ + +Timerlat tracer documentation: + +AUTHOR +------ +Written by Daniel Bristot de Oliveira + +REPORTING BUGS +-------------- +Report bugs to + +LICENSE +------- +rtla is Free Software licensed under the GNU GPLv2 + +COPYING +------- +Copyright \(C) 2021 Red Hat, Inc. Free use of this software is granted under +the terms of the GNU Public License (GPL).