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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT 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 E8226C2D0E7 for ; Wed, 1 Apr 2020 10:18:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BABCC2077D for ; Wed, 1 Apr 2020 10:18:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732318AbgDAKSL (ORCPT ); Wed, 1 Apr 2020 06:18:11 -0400 Received: from mga01.intel.com ([192.55.52.88]:34152 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732299AbgDAKSE (ORCPT ); Wed, 1 Apr 2020 06:18:04 -0400 IronPort-SDR: NfvXKn7HxQzMvqEo2nF/2pDtqgGo50V6HQ74S7Ar/J1V+tVTsgkMsMiQRY8aqA1b9q9F8Y08k5 3lY/RvI6ciOw== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga004.jf.intel.com ([10.7.209.38]) by fmsmga101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 01 Apr 2020 03:18:02 -0700 IronPort-SDR: KOxMh6BDZWhdEvjG0+98QrgCQxbrdI2uVjN99WL2peT+0AbE1R2ng6vk+rYq6H5mZL74HmLT6c sOv2cFLgjQcw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.72,331,1580803200"; d="scan'208";a="395925635" Received: from ahunter-desktop.fi.intel.com ([10.237.72.87]) by orsmga004.jf.intel.com with ESMTP; 01 Apr 2020 03:18:02 -0700 From: Adrian Hunter To: Arnaldo Carvalho de Melo Cc: Jiri Olsa , Andi Kleen , linux-kernel@vger.kernel.org, Adrian Hunter Subject: [PATCH 16/16] perf tools: Add support for leader-sampling with AUX area events Date: Wed, 1 Apr 2020 13:16:13 +0300 Message-Id: <20200401101613.6201-17-adrian.hunter@intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200401101613.6201-1-adrian.hunter@intel.com> References: <20200401101613.6201-1-adrian.hunter@intel.com> Organization: Intel Finland Oy, Registered Address: PL 281, 00181 Helsinki, Business Identity Code: 0357606 - 4, Domiciled in Helsinki Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When AUX area events are used in sampling mode, they must be the group leader, but the group leader is also used for leader-sampling. However, it is not desirable to use an AUX area event as the leader for leader-sampling, because it doesn't have any samples of its own. To support leader-sampling with AUX area events, use the 2nd event of the group as the "leader" for the purposes of leader-sampling. Example: # perf record --kcore --aux-sample -e '{intel_pt//,cycles,instructions}:S' -c 10000 uname [ perf record: Woken up 3 times to write data ] [ perf record: Captured and wrote 0.786 MB perf.data ] # perf report Samples: 380 of events 'anon group { cycles, instructions }', Event count (approx.): 3026164 Children Self Command Shared Object Symbol + 38.76% 42.65% 0.00% 0.00% uname [kernel.kallsyms] [k] __x86_indirect_thunk_rax + 35.82% 31.33% 0.00% 0.00% uname ld-2.28.so [.] _dl_start_user + 34.29% 29.74% 0.55% 0.47% uname ld-2.28.so [.] _dl_start + 33.73% 28.62% 1.60% 0.97% uname ld-2.28.so [.] dl_main + 33.19% 29.04% 0.52% 0.32% uname ld-2.28.so [.] _dl_sysdep_start + 27.83% 33.74% 0.00% 0.00% uname [kernel.kallsyms] [k] do_syscall_64 + 26.76% 33.29% 0.00% 0.00% uname [kernel.kallsyms] [k] entry_SYSCALL_64_after_hwframe + 23.78% 20.33% 5.97% 5.25% uname [kernel.kallsyms] [k] page_fault + 23.18% 24.60% 0.00% 0.00% uname libc-2.28.so [.] __libc_start_main + 22.64% 24.37% 0.00% 0.00% uname uname [.] _start + 21.04% 23.27% 0.00% 0.00% uname uname [.] main + 19.48% 18.08% 3.72% 3.64% uname ld-2.28.so [.] _dl_relocate_object + 19.47% 21.81% 0.00% 0.00% uname libc-2.28.so [.] setlocale + 19.44% 21.56% 0.52% 0.61% uname libc-2.28.so [.] _nl_find_locale + 17.87% 19.66% 0.00% 0.00% uname libc-2.28.so [.] _nl_load_locale_from_archive + 15.71% 13.73% 0.53% 0.52% uname [kernel.kallsyms] [k] do_page_fault + 15.18% 13.21% 1.03% 0.68% uname [kernel.kallsyms] [k] handle_mm_fault + 14.15% 12.53% 1.01% 1.12% uname [kernel.kallsyms] [k] __handle_mm_fault + 12.03% 9.67% 0.54% 0.32% uname ld-2.28.so [.] _dl_map_object + 10.55% 8.48% 0.00% 0.00% uname ld-2.28.so [.] openaux + 10.55% 20.20% 0.52% 0.61% uname libc-2.28.so [.] __run_exit_handlers Signed-off-by: Adrian Hunter --- tools/perf/Documentation/perf-list.txt | 3 ++ tools/perf/util/record.c | 43 +++++++++++++++++++++++--- 2 files changed, 41 insertions(+), 5 deletions(-) diff --git a/tools/perf/Documentation/perf-list.txt b/tools/perf/Documentation/perf-list.txt index 6345db33c533..cb23667531ab 100644 --- a/tools/perf/Documentation/perf-list.txt +++ b/tools/perf/Documentation/perf-list.txt @@ -258,6 +258,9 @@ Normally all events in an event group sample, but with :S only the first event (the leader) samples, and it only reads the values of the other events in the group. +However, in the case AUX area events (e.g. Intel PT or CoreSight), the AUX +area event must be the leader, so then the second event samples, not the first. + OPTIONS ------- diff --git a/tools/perf/util/record.c b/tools/perf/util/record.c index 924c58b3fc36..6d3e3df6e2a1 100644 --- a/tools/perf/util/record.c +++ b/tools/perf/util/record.c @@ -167,17 +167,46 @@ bool perf_can_aux_sample(void) return true; } -static void perf_evsel__config_leader_sampling(struct evsel *evsel) +/* + * perf_evsel__config_leader_sampling() uses special rules for leader sampling. + * However, if the leader is an AUX area event, then assume the event to sample + * is the next event. + */ +static struct evsel *perf_evsel__read_sampler(struct evsel *evsel, + struct evlist *evlist) +{ + struct evsel *leader = evsel->leader; + + if (perf_evsel__is_aux_event(leader)) { + evlist__for_each_entry(evlist, evsel) { + if (evsel->leader == leader && evsel != evsel->leader) + return evsel; + } + } + + return leader; +} + +static void perf_evsel__config_leader_sampling(struct evsel *evsel, + struct evlist *evlist) { struct perf_event_attr *attr = &evsel->core.attr; struct evsel *leader = evsel->leader; + struct evsel *read_sampler; + + if (!leader->sample_read) + return; + + read_sampler = perf_evsel__read_sampler(evsel, evlist); - if (leader == evsel || !leader->sample_read) + if (evsel == read_sampler) return; /* - * Disable sampling for all group members other - * than leader in case leader 'leads' the sampling. + * 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. */ attr->freq = 0; attr->sample_freq = 0; @@ -188,8 +217,12 @@ static void perf_evsel__config_leader_sampling(struct evsel *evsel) * We don't get a sample for slave events, we make them when delivering * the group leader sample. Set the slave event to follow the master * sample_type to ease up reporting. + * An AUX area event also has sample_type requirements, so also include + * the sample type bits from the leader's sample_type to cover that + * case. */ - attr->sample_type = leader->core.attr.sample_type; + attr->sample_type = read_sampler->core.attr.sample_type | + leader->core.attr.sample_type; } void perf_evlist__config(struct evlist *evlist, struct record_opts *opts, -- 2.17.1