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 29AB4C433EF for ; Tue, 12 Jul 2022 12:57:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232442AbiGLM5n (ORCPT ); Tue, 12 Jul 2022 08:57:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44402 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232270AbiGLM5k (ORCPT ); Tue, 12 Jul 2022 08:57:40 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C4344AC071; Tue, 12 Jul 2022 05:57:39 -0700 (PDT) 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 7ED44B81868; Tue, 12 Jul 2022 12:57:38 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E70A8C341CD; Tue, 12 Jul 2022 12:57:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1657630657; bh=cW1C3A28y7M0Wa7SoYZtf30sJKBFXl9X73+ZlF8Vvt8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=sUTSW/a1JicHdPlFQb9l3h71/9LnyigR59l49n/v7oBw2LeaxBY2ck+TU73EjTcsN pIDqblBd2L2CT2/ESo9U06JvrbnQ3VSrbu7sRMchdmQJHbabKRG3sRhv0x0IsOHJ8r yV/0n4mH4rwH0q0AjQxMSQYWG6EmM41NQ/StJpX41vizngigb6gjzLGULuzBn6I5Vg A5mNZYxpLG+HpnIfguVS2HWXDnALEcFE8TRH9TAF23mh/yDrw+vQxSGJ2nAjEUdEQ9 wbZQWSpb0mZtAaAoEw0EOBoxiTLUf94PYLpDeWn9HJaqcigAefcHZ6RKzSn6eyfnXy 95z5EU8Nh5g4Q== Received: by quaco.ghostprotocols.net (Postfix, from userid 1000) id 3B13E40374; Tue, 12 Jul 2022 09:57:34 -0300 (-03) Date: Tue, 12 Jul 2022 09:57:34 -0300 From: Arnaldo Carvalho de Melo To: Namhyung Kim Cc: Jiri Olsa , Ingo Molnar , Peter Zijlstra , LKML , Ian Rogers , linux-perf-users@vger.kernel.org, Will Deacon , Waiman Long , Boqun Feng , Davidlohr Bueso Subject: Re: [PATCHSET 0/7] perf lock: New lock contention tracepoints support (v4) Message-ID: References: <20220615163222.1275500-1-namhyung@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220615163222.1275500-1-namhyung@kernel.org> X-Url: http://acmel.wordpress.com Precedence: bulk List-ID: X-Mailing-List: linux-perf-users@vger.kernel.org Em Wed, Jun 15, 2022 at 09:32:15AM -0700, Namhyung Kim escreveu: > Hello, > > Kernel v5.19 will have a new set of tracepoints to track lock > contentions for various lock types. Unlike tracepoints in LOCKDEP and > LOCK_STAT, it's hit only for contended locks and lock names are not > available. So it needs to collect stack traces and display the caller > function instead. Applied to tmp.perf/core, performing some further tests and then will push to perf/core. Thanks for you work on this! - Arnaldo > Changes in v4) > * add Acked-by from Ian > * more comments on trace_lock_handler > * don't create stats in the contention_end handler > > Changes in v3) > * fix build error > * support data from different kernels/machines > * skip bad stat unless there's actual bad ones > > Changes in v2) > * add Acked-by from Ian > * print time with a unit for compact output > * add some comments (Ian) > * remove already applied patch > > This patchset merely adds support for the new tracepoints to the > existing perf lock commands. So there's no change to the user. Later > I'll add new a sub-command dedicated to the tracepoints to make use of > the additional information. > > Example output: > > $ sudo perf lock record -a sleep 3 > > $ perf lock report -F acquired,contended,avg_wait,wait_total > > Name acquired contended avg wait total wait > > update_blocked_a... 40 40 3.61 us 144.45 us > kernfs_fop_open+... 5 5 3.64 us 18.18 us > _nohz_idle_balance 3 3 2.65 us 7.95 us > tick_do_update_j... 1 1 6.04 us 6.04 us > ep_scan_ready_list 1 1 3.93 us 3.93 us > ... > > You can find the code in the 'perf/lock-contention-v4' branch at > > git://git.kernel.org/pub/scm/linux/kernel/git/namhyung/linux-perf.git > > Thanks, > Namhyung > > > Namhyung Kim (7): > perf lock: Print wait times with unit > perf lock: Allow to use different kernel symbols > perf lock: Skip print_bad_events() if nothing bad > perf lock: Add lock contention tracepoints record support > perf lock: Handle lock contention tracepoints > perf record: Allow to specify max stack depth of fp callchain > perf lock: Look up callchain for the contended locks > > tools/perf/Documentation/perf-lock.txt | 7 + > tools/perf/Documentation/perf-record.txt | 5 + > tools/perf/builtin-lock.c | 426 ++++++++++++++++++++++- > tools/perf/util/callchain.c | 18 +- > 4 files changed, 434 insertions(+), 22 deletions(-) > > > base-commit: 9886142c7a2226439c1e3f7d9b69f9c7094c3ef6 > -- > 2.36.1.476.g0c4daa206d-goog -- - Arnaldo