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 X-Spam-Level: X-Spam-Status: No, score=-17.6 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_IN_DEF_DKIM_WL 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 009F6C433E0 for ; Tue, 4 Aug 2020 13:34:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D429C206DA for ; Tue, 4 Aug 2020 13:34:02 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="g2//3kmY" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726533AbgHDNeB (ORCPT ); Tue, 4 Aug 2020 09:34:01 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48808 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725921AbgHDNeB (ORCPT ); Tue, 4 Aug 2020 09:34:01 -0400 Received: from mail-wm1-x342.google.com (mail-wm1-x342.google.com [IPv6:2a00:1450:4864:20::342]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F1C3FC061756 for ; Tue, 4 Aug 2020 06:34:00 -0700 (PDT) Received: by mail-wm1-x342.google.com with SMTP id d190so2691744wmd.4 for ; Tue, 04 Aug 2020 06:34:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=J1/mYzIP2hMyjkq4qwIx7vKFLfGV8E9+xnljo9oNBug=; b=g2//3kmYqQevKfe9SCxyV6EZhOfaU+P+Cy9nDkqvNsV+5/24wqAVcu/5670F9bItAF kZ+KpSx8MmOK7MWb1gK9gTffVBJKT3jM2ZYsXwG+DAgcDPTTCOWQuj/I5vNUXZthINh0 xHNQzGNUPZHfw/KK7oFFwG2obkokd6owf3M6AJiffKH4bsQYpX+DpisRtrdhYpxeR84P QDR1ZTwEsRgQ+EGJmjqhRRBjqaSsk7rK9/1z0oYSCbxox9ByTlQKYcyRhu4/RhiRuV4T btE6hTKn6Qd1gaziphYJ3e1eH3H7jANcKyBQJXIDcnYdDcwxDRPdrxcXVA8bcUYL69l/ VVSA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=J1/mYzIP2hMyjkq4qwIx7vKFLfGV8E9+xnljo9oNBug=; b=L9LhrFp6X5YEJlYDd8iSyNmNwh3jL+ZtO5KbjSVUeXfgvZi7LAA8Y9BJaCJa5betmv 8U4LNZFO2Meizy1pD2wECinXfIJ8tqQYryp7EpPjvtdPEtGA9GTE0nW8NNlW/qL53TNi +ABlGtokPrjGGwFC4iMZVoseQNNLlg8FGwqwrSQBrwG1+kkUW/nOmwYIZgFZxjO/wlP8 bwSe2EKRBQYl37QWJn8c7DIbAzYCZRBvtIQpNSODw4/u8kxGnD9/LG/3Fxc6BGfgkbBP iR8yeQKX1xiiwFMQte6LsJMMn4tpHFegMmzpuLUUMo5liEx9xu2ehh6m1BUkW7kuLO09 tbvA== X-Gm-Message-State: AOAM533Rh8frBwRiew7x/IsVw1nZ2WPsx3qSekSuqDUuroVLBXwwuULZ vu/4WQF0/BrJyUTxSvwUSHCjjiy8hlbB7VkC5ezd7g== X-Google-Smtp-Source: ABdhPJxAjw5E9Gzy3aeP53ZI+pqeCPa5gfx7N9vxRRtQkTi2sm8CbIjAo67QAvYWwoPiNQ7r1jW389h/z4hP4PYpkxw= X-Received: by 2002:a1c:e0c2:: with SMTP id x185mr4073668wmg.124.1596548039304; Tue, 04 Aug 2020 06:33:59 -0700 (PDT) MIME-Version: 1.0 References: <20200728085734.609930-1-irogers@google.com> <20200728085734.609930-5-irogers@google.com> <969ef797-59ea-69d0-24b9-33bcdff106a1@intel.com> In-Reply-To: <969ef797-59ea-69d0-24b9-33bcdff106a1@intel.com> From: Ian Rogers Date: Tue, 4 Aug 2020 06:33:47 -0700 Message-ID: Subject: Re: [PATCH v2 4/5] perf record: Don't clear event's period if set by a term To: Adrian Hunter Cc: Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , Alexei Starovoitov , Daniel Borkmann , Martin KaFai Lau , Song Liu , Yonghong Song , Andrii Nakryiko , John Fastabend , KP Singh , Andi Kleen , Athira Rajeev , LKML , Networking , bpf , Stephane Eranian Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Aug 4, 2020 at 3:08 AM Adrian Hunter wrote: > > On 28/07/20 11:57 am, Ian Rogers wrote: > > If events in a group explicitly set a frequency or period with leader > > sampling, don't disable the samples on those events. > > > > Prior to 5.8: > > perf record -e '{cycles/period=12345000/,instructions/period=6789000/}:S' > > Might be worth explaining this use-case some more. > Perhaps add it to the leader sampling documentation for perf-list. > > > would clear the attributes then apply the config terms. In commit > > 5f34278867b7 leader sampling configuration was moved to after applying the > > config terms, in the example, making the instructions' event have its period > > cleared. > > This change makes it so that sampling is only disabled if configuration > > terms aren't present. > > > > Fixes: 5f34278867b7 ("perf evlist: Move leader-sampling configuration") > > Signed-off-by: Ian Rogers > > --- > > tools/perf/util/record.c | 28 ++++++++++++++++++++-------- > > 1 file changed, 20 insertions(+), 8 deletions(-) > > > > diff --git a/tools/perf/util/record.c b/tools/perf/util/record.c > > index a4cc11592f6b..01d1c6c613f7 100644 > > --- a/tools/perf/util/record.c > > +++ b/tools/perf/util/record.c > > @@ -2,6 +2,7 @@ > > #include "debug.h" > > #include "evlist.h" > > #include "evsel.h" > > +#include "evsel_config.h" > > #include "parse-events.h" > > #include > > #include > > @@ -38,6 +39,9 @@ static void evsel__config_leader_sampling(struct evsel *evsel, struct evlist *ev > > struct perf_event_attr *attr = &evsel->core.attr; > > struct evsel *leader = evsel->leader; > > struct evsel *read_sampler; > > + struct evsel_config_term *term; > > + struct list_head *config_terms = &evsel->config_terms; > > + int term_types, freq_mask; > > > > if (!leader->sample_read) > > return; > > @@ -47,16 +51,24 @@ static void evsel__config_leader_sampling(struct evsel *evsel, struct evlist *ev > > if (evsel == read_sampler) > > return; > > > > + /* Determine the evsel's config term types. */ > > + term_types = 0; > > + list_for_each_entry(term, config_terms, list) { > > + term_types |= 1 << term->type; > > + } > > /* > > - * Disable sampling for all group members other than the leader in > > - * case the leader 'leads' the sampling, except when the leader is an > > - * AUX area event, in which case the 2nd event in the group is the one > > - * that 'leads' the sampling. > > + * Disable sampling for all group members except those with explicit > > + * config terms or the leader. In the case of an AUX area event, the 2nd > > + * event in the group is the one that 'leads' the sampling. > > */ > > - attr->freq = 0; > > - attr->sample_freq = 0; > > - attr->sample_period = 0; > > - attr->write_backward = 0; > > + freq_mask = (1 << EVSEL__CONFIG_TERM_FREQ) | (1 << EVSEL__CONFIG_TERM_PERIOD); > > + if ((term_types & freq_mask) == 0) { > > It would be nicer to have a helper e.g. > > if (!evsel__have_config_term(evsel, FREQ) && > !evsel__have_config_term(evsel, PERIOD)) { Sure. The point of doing it this way was to avoid repeatedly iterating over the config term list. > > + attr->freq = 0; > > + attr->sample_freq = 0; > > + attr->sample_period = 0; > > If we are not sampling, then maybe we should also put here: > > attr->write_backward = 0; > > > + } > > Then, if we are sampling this evsel shouldn't the backward setting > match the leader? e.g. > > if (attr->sample_freq) > attr->write_backward = leader->core.attr.write_backward; Perhaps that should be a follow up change? This change is trying to make the behavior match the previous behavior. Thanks, Ian > > + if ((term_types & (1 << EVSEL__CONFIG_TERM_OVERWRITE)) == 0) > > + attr->write_backward = 0; > > > > /* > > * We don't get a sample for slave events, we make them when delivering > > >