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 5492FC433EF for ; Tue, 11 Jan 2022 17:32:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344775AbiAKRcC (ORCPT ); Tue, 11 Jan 2022 12:32:02 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42902 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344429AbiAKRbX (ORCPT ); Tue, 11 Jan 2022 12:31:23 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BB195C061212; Tue, 11 Jan 2022 09:31:20 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 7A2BEB81C53; Tue, 11 Jan 2022 17:31:19 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 35839C36AEB; Tue, 11 Jan 2022 17:31:19 +0000 (UTC) Received: from rostedt by gandalf.local.home with local (Exim 4.95) (envelope-from ) id 1n7KzO-0032JW-Cu; Tue, 11 Jan 2022 12:31:18 -0500 Message-ID: <20220111173118.234471647@goodmis.org> User-Agent: quilt/0.66 Date: Tue, 11 Jan 2022 12:30:58 -0500 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Ingo Molnar , Andrew Morton , Tao Zhou , Ingo Molnar , Tom Zanussi , Masami Hiramatsu , Juri Lelli , Clark Williams , John Kacur , Peter Zijlstra , Thomas Gleixner , Sebastian Andrzej Siewior , Daniel Bristot de Oliveira , linux-rt-users@vger.kernel.org, linux-trace-devel@vger.kernel.org Subject: [for-next][PATCH 27/31] rtla: Add rtla timerlat documentation References: <20220111173030.999527342@goodmis.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Daniel Bristot de Oliveira Man page for rtla timerlat tool. Link: https://lkml.kernel.org/r/644599d0041c53a2d0646ca72eaa783100dc32a2.1638182284.git.bristot@kernel.org Cc: Tao Zhou 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 Signed-off-by: Steven Rostedt --- .../rtla/common_timerlat_description.rst | 10 ++++ Documentation/tools/rtla/rtla-timerlat.rst | 57 +++++++++++++++++++ 2 files changed, 67 insertions(+) create mode 100644 Documentation/tools/rtla/common_timerlat_description.rst create mode 100644 Documentation/tools/rtla/rtla-timerlat.rst diff --git a/Documentation/tools/rtla/common_timerlat_description.rst b/Documentation/tools/rtla/common_timerlat_description.rst new file mode 100644 index 000000000000..321201cb8597 --- /dev/null +++ b/Documentation/tools/rtla/common_timerlat_description.rst @@ -0,0 +1,10 @@ +The **rtla timerlat** 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 enable the trace of the most relevant information via +**osnoise:** tracepoints. diff --git a/Documentation/tools/rtla/rtla-timerlat.rst b/Documentation/tools/rtla/rtla-timerlat.rst new file mode 100644 index 000000000000..44a49e6f302b --- /dev/null +++ b/Documentation/tools/rtla/rtla-timerlat.rst @@ -0,0 +1,57 @@ +================ +rtla-timerlat +================ +------------------------------------------- +Measures the operating system timer latency +------------------------------------------- + +:Manual section: 1 + +SYNOPSIS +======== +**rtla timerlat** [*MODE*] ... + +DESCRIPTION +=========== + +.. include:: common_timerlat_description.rst + +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** mode displays a summary of the periodic output +from the *timerlat* tracer. The **rtla hist hist** 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 + +.. include:: common_appendix.rst -- 2.33.0