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 8A716C4332F for ; Tue, 13 Dec 2022 14:44:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235771AbiLMOoK (ORCPT ); Tue, 13 Dec 2022 09:44:10 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60104 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235837AbiLMOoJ (ORCPT ); Tue, 13 Dec 2022 09:44:09 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9B33E2FE; Tue, 13 Dec 2022 06:44:08 -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 4645FB811D8; Tue, 13 Dec 2022 14:44:07 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9C77CC433EF; Tue, 13 Dec 2022 14:44:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1670942645; bh=ITWlJPRHLiVkjAwuGTarFPRTpQtiWPKN8YZPZTB5+Ec=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=LXofy+aMduC6B9MfC3WZE0lQqiRZBaj4sij5umxyw1Uegbs2Vo3Izg8hmPsHhvG9E VW6KtuJIkHFlM89Vs492/2iFBynyyt4LVYkmuEBshZ9NQcKQy350yuXpjSESxJCdPm dlNo1FBOlWDYQ3Mo381eWPkQCacFhrHFoPZJ02sF6D+I76tyyQ95g7+6ODXx5eSdQw QI9vO44PGn27xc34uZOuKfp8fitewFc1svBivOFQUPaBS5HzsjIVwK6504OAj6TRvP mdCWkvRBTpUeX+ESxjeSE+NthSodHBl+EkaVu5mnOc4hDpw0Wu2NeZoLdldrHssazq U0SSJXbEVtM7g== Received: by quaco.ghostprotocols.net (Postfix, from userid 1000) id 8D06E40367; Tue, 13 Dec 2022 11:44:02 -0300 (-03) Date: Tue, 13 Dec 2022 11:44:02 -0300 From: Arnaldo Carvalho de Melo To: James Clark Cc: =?iso-8859-1?Q?Adri=E1n?= Herrera Arcila , linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, leo.yan@linaro.org, songliubraving@fb.com, peterz@infradead.org, mingo@redhat.com, mark.rutland@arm.com, alexander.shishkin@linux.intel.com, jolsa@kernel.org, namhyung@kernel.org Subject: Re: [PATCH 2/2] perf stat: fix unexpected delay behaviour Message-ID: References: <20220729161244.10522-1-adrian.herrera@arm.com> <20220729161244.10522-2-adrian.herrera@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-Url: http://acmel.wordpress.com Precedence: bulk List-ID: X-Mailing-List: linux-perf-users@vger.kernel.org Em Mon, Aug 01, 2022 at 09:20:37AM +0100, James Clark escreveu: > > > On 29/07/2022 17:12, Adrián Herrera Arcila wrote: > > The described --delay behaviour is to delay the enablement of events, but > > not the execution of the command, if one is passed, which is incorrectly > > the current behaviour. > > > > This patch decouples the enablement from the delay, and enables events > > before or after launching the workload dependent on the options passed > > by the user. This code structure is inspired by that in perf-record, and > > tries to be consistent with it. > > > > Link: https://lore.kernel.org/linux-perf-users/7BFD066E-B0A8-49D4-B635-379328F0CF4C@fb.com > > Fixes: d0a0a511493d ("perf stat: Fix forked applications enablement of counters") > > Signed-off-by: Adrián Herrera Arcila > > --- > > tools/perf/builtin-stat.c | 56 ++++++++++++++++++++++----------------- > > 1 file changed, 32 insertions(+), 24 deletions(-) > > Looks good to me. Fixes the counter delay issue and the code is pretty > similar to perf record now. Although I would wait for Leo's or Song's > comment as well because they were involved. I think I didn't notice Leo's ack, it still applies, so I'm doing it now. - Arnaldo > Reviewed-by: James Clark > > > > > diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c > > index 318ffd119dad..f98c823b16dd 100644 > > --- a/tools/perf/builtin-stat.c > > +++ b/tools/perf/builtin-stat.c > > @@ -559,7 +559,7 @@ static bool handle_interval(unsigned int interval, int *times) > > return false; > > } > > > > -static int enable_counters(void) > > +static int enable_bpf_counters(void) > > { > > struct evsel *evsel; > > int err; > > @@ -572,28 +572,6 @@ static int enable_counters(void) > > if (err) > > return err; > > } > > - > > - if (stat_config.initial_delay < 0) { > > - pr_info(EVLIST_DISABLED_MSG); > > - return 0; > > - } > > - > > - if (stat_config.initial_delay > 0) { > > - pr_info(EVLIST_DISABLED_MSG); > > - usleep(stat_config.initial_delay * USEC_PER_MSEC); > > - } > > - > > - /* > > - * We need to enable counters only if: > > - * - we don't have tracee (attaching to task or cpu) > > - * - we have initial delay configured > > - */ > > - if (!target__none(&target) || stat_config.initial_delay) { > > - if (!all_counters_use_bpf) > > - evlist__enable(evsel_list); > > - if (stat_config.initial_delay > 0) > > - pr_info(EVLIST_ENABLED_MSG); > > - } > > return 0; > > } > > > > @@ -966,10 +944,24 @@ static int __run_perf_stat(int argc, const char **argv, int run_idx) > > return err; > > } > > > > - err = enable_counters(); > > + err = enable_bpf_counters(); > > if (err) > > return -1; > > > > + /* > > + * Enable events manually here if perf-stat is run: > > + * 1. with a target (any of --all-cpus, --cpu, --pid or --tid) > > + * 2. without measurement delay (no --delay) > > + * 3. without all events associated to BPF > > + * > > + * This is because if run with a target, events are not enabled > > + * on exec if a workload is passed, and because there is no delay > > + * we ensure to enable them before the workload starts > > + */ > > + if (!target__none(&target) && !stat_config.initial_delay && > > + !all_counters_use_bpf) > > + evlist__enable(evsel_list); > > + > > /* Exec the command, if any */ > > if (forks) > > evlist__start_workload(evsel_list); > > @@ -977,6 +969,22 @@ static int __run_perf_stat(int argc, const char **argv, int run_idx) > > t0 = rdclock(); > > clock_gettime(CLOCK_MONOTONIC, &ref_time); > > > > + /* > > + * If a measurement delay was specified, start it, and if positive, > > + * enable events manually after. We respect the delay even if all > > + * events are associated to BPF > > + */ > > + if (stat_config.initial_delay) { > > + /* At this point, events are guaranteed disabled */ > > + pr_info(EVLIST_DISABLED_MSG); > > + if (stat_config.initial_delay > 0) { > > + usleep(stat_config.initial_delay * USEC_PER_MSEC); > > + if (!all_counters_use_bpf) > > + evlist__enable(evsel_list); > > + pr_info(EVLIST_ENABLED_MSG); > > + } > > + } > > + > > if (forks) { > > if (interval || timeout || evlist__ctlfd_initialized(evsel_list)) > > status = dispatch_events(forks, timeout, interval, ×); -- - Arnaldo