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 B8506C25B48 for ; Thu, 26 Oct 2023 18:29:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232356AbjJZS3K (ORCPT ); Thu, 26 Oct 2023 14:29:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51046 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230143AbjJZS3J (ORCPT ); Thu, 26 Oct 2023 14:29:09 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.65]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2DC071B9 for ; Thu, 26 Oct 2023 11:29:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1698344944; x=1729880944; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=+pl4vKRGKy6O4Zjlj2CzoICXCXfxh9aAW36MHBCkKNU=; b=fBbr7uC2OTeTMp/Lns0Z6/w+5ca9Ognde9+dd1zsQ2Yw53Wze/Es9dH1 KJUywYTOFlJfxOIIzFL/39VaoZrklMr4JhgjswEpqIh3i+99NQ65bptd/ B58khVusXok1TxCcIMmMRV79ZZajB/y2wnd94/1lBfQVykjuYYGevqGrI EJY9AdbNdTO8T1DswK/zsrkPkdGhjuBN0GK2rahHRbJYM52OPKcWnSGGE nHgK9O8J205ydcTZg1oW86pMsm07UsAeiKpvfoXMWlJonI6hshOPDD/WV OEs0AbSvFeGt8NLCWlSizG/tDMiATd3zY4paFfeaxpYhn/SDBiKJ6NHs9 Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10875"; a="391495755" X-IronPort-AV: E=Sophos;i="6.03,254,1694761200"; d="scan'208";a="391495755" Received: from fmviesa002.fm.intel.com ([10.60.135.142]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Oct 2023 11:29:02 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.03,254,1694761200"; d="scan'208";a="576899" Received: from linux.intel.com ([10.54.29.200]) by fmviesa002.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Oct 2023 11:28:51 -0700 Received: from [10.209.128.139] (kliang2-mobl1.ccr.corp.intel.com [10.209.128.139]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by linux.intel.com (Postfix) with ESMTPS id 2CFBB580E30; Thu, 26 Oct 2023 11:29:00 -0700 (PDT) Message-ID: Date: Thu, 26 Oct 2023 14:28:59 -0400 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH V5 8/8] perf tools: Add branch counter knob Content-Language: en-US To: Ian Rogers Cc: peterz@infradead.org, mingo@redhat.com, acme@kernel.org, linux-kernel@vger.kernel.org, mark.rutland@arm.com, alexander.shishkin@linux.intel.com, jolsa@kernel.org, namhyung@kernel.org, adrian.hunter@intel.com, ak@linux.intel.com, eranian@google.com, alexey.v.bayduraev@linux.intel.com, tinghao.zhang@intel.com References: <20231025201626.3000228-1-kan.liang@linux.intel.com> <20231025201626.3000228-8-kan.liang@linux.intel.com> From: "Liang, Kan" In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2023-10-25 10:12 p.m., Ian Rogers wrote: > On Wed, Oct 25, 2023 at 1:16 PM wrote: >> >> From: Kan Liang >> >> Add a new branch filter, "counter", for the branch counter option. It is >> used to mark the events which should be logged in the branch. If it is >> applied with the -j option, the counters of all the events should be >> logged in the branch. If the legacy kernel doesn't support the new >> branch sample type, switching off the branch counter filter. >> >> The stored counter values in each branch are displayed right after the >> regular branch stack information via perf report -D. >> >> Usage examples: >> >> perf record -e "{branch-instructions,branch-misses}:S" -j any,counter >> >> Only the first event, branch-instructions, collect the LBR. Both >> branch-instructions and branch-misses are marked as logged events. >> The occurrences information of them can be found in the branch stack >> extension space of each branch. >> >> perf record -e "{cpu/branch-instructions,branch_type=any/, >> cpu/branch-misses,branch_type=counter/}" >> >> Only the first event, branch-instructions, collect the LBR. Only the >> branch-misses event is marked as a logged event. >> >> Signed-off-by: Kan Liang > > Reviewed-by: Ian Rogers Thanks Ian for the review. > > Perhaps add a test somewhere like: > https://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools-next.git/tree/tools/perf/tests/shell/record.sh > for coverage when hardware supports the feature. Sure, I will add a test when posting the perf tool patches. Thanks, Kan > > Thanks, > Ian > >> --- >> >> No changes since V4 >> >> tools/perf/Documentation/perf-record.txt | 4 +++ >> tools/perf/util/evsel.c | 31 ++++++++++++++++++++++- >> tools/perf/util/evsel.h | 1 + >> tools/perf/util/parse-branch-options.c | 1 + >> tools/perf/util/perf_event_attr_fprintf.c | 1 + >> tools/perf/util/sample.h | 1 + >> tools/perf/util/session.c | 15 +++++++++-- >> 7 files changed, 51 insertions(+), 3 deletions(-) >> >> diff --git a/tools/perf/Documentation/perf-record.txt b/tools/perf/Documentation/perf-record.txt >> index d5217be012d7..b6afe7cc948d 100644 >> --- a/tools/perf/Documentation/perf-record.txt >> +++ b/tools/perf/Documentation/perf-record.txt >> @@ -442,6 +442,10 @@ following filters are defined: >> 4th-Gen Xeon+ server), the save branch type is unconditionally enabled >> when the taken branch stack sampling is enabled. >> - priv: save privilege state during sampling in case binary is not available later >> + - counter: save occurrences of the event since the last branch entry. Currently, the >> + feature is only supported by a newer CPU, e.g., Intel Sierra Forest and >> + later platforms. An error out is expected if it's used on the unsupported >> + kernel or CPUs. >> >> + >> The option requires at least one branch type among any, any_call, any_ret, ind_call, cond. >> diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c >> index a8a5ff87cc1f..58a9b8c82790 100644 >> --- a/tools/perf/util/evsel.c >> +++ b/tools/perf/util/evsel.c >> @@ -1831,6 +1831,8 @@ static int __evsel__prepare_open(struct evsel *evsel, struct perf_cpu_map *cpus, >> >> static void evsel__disable_missing_features(struct evsel *evsel) >> { >> + if (perf_missing_features.branch_counters) >> + evsel->core.attr.branch_sample_type &= ~PERF_SAMPLE_BRANCH_COUNTERS; >> if (perf_missing_features.read_lost) >> evsel->core.attr.read_format &= ~PERF_FORMAT_LOST; >> if (perf_missing_features.weight_struct) { >> @@ -1884,7 +1886,12 @@ bool evsel__detect_missing_features(struct evsel *evsel) >> * Must probe features in the order they were added to the >> * perf_event_attr interface. >> */ >> - if (!perf_missing_features.read_lost && >> + if (!perf_missing_features.branch_counters && >> + (evsel->core.attr.branch_sample_type & PERF_SAMPLE_BRANCH_COUNTERS)) { >> + perf_missing_features.branch_counters = true; >> + pr_debug2("switching off branch counters support\n"); >> + return true; >> + } else if (!perf_missing_features.read_lost && >> (evsel->core.attr.read_format & PERF_FORMAT_LOST)) { >> perf_missing_features.read_lost = true; >> pr_debug2("switching off PERF_FORMAT_LOST support\n"); >> @@ -2344,6 +2351,18 @@ u64 evsel__bitfield_swap_branch_flags(u64 value) >> return new_val; >> } >> >> +static inline bool evsel__has_branch_counters(const struct evsel *evsel) >> +{ >> + struct evsel *cur, *leader = evsel__leader(evsel); >> + >> + evlist__for_each_entry(evsel->evlist, cur) { >> + if ((leader == evsel__leader(cur)) && >> + (cur->core.attr.branch_sample_type & PERF_SAMPLE_BRANCH_COUNTERS)) >> + return true; >> + } >> + return false; >> +} >> + >> int evsel__parse_sample(struct evsel *evsel, union perf_event *event, >> struct perf_sample *data) >> { >> @@ -2577,6 +2596,16 @@ int evsel__parse_sample(struct evsel *evsel, union perf_event *event, >> >> OVERFLOW_CHECK(array, sz, max_size); >> array = (void *)array + sz; >> + >> + if (evsel__has_branch_counters(evsel)) { >> + OVERFLOW_CHECK_u64(array); >> + >> + data->branch_stack_cntr = (u64 *)array; >> + sz = data->branch_stack->nr * sizeof(u64); >> + >> + OVERFLOW_CHECK(array, sz, max_size); >> + array = (void *)array + sz; >> + } >> } >> >> if (type & PERF_SAMPLE_REGS_USER) { >> diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h >> index 848534ec74fa..85f24c986392 100644 >> --- a/tools/perf/util/evsel.h >> +++ b/tools/perf/util/evsel.h >> @@ -191,6 +191,7 @@ struct perf_missing_features { >> bool code_page_size; >> bool weight_struct; >> bool read_lost; >> + bool branch_counters; >> }; >> >> extern struct perf_missing_features perf_missing_features; >> diff --git a/tools/perf/util/parse-branch-options.c b/tools/perf/util/parse-branch-options.c >> index fd67d204d720..f7f7aff3d85a 100644 >> --- a/tools/perf/util/parse-branch-options.c >> +++ b/tools/perf/util/parse-branch-options.c >> @@ -36,6 +36,7 @@ static const struct branch_mode branch_modes[] = { >> BRANCH_OPT("stack", PERF_SAMPLE_BRANCH_CALL_STACK), >> BRANCH_OPT("hw_index", PERF_SAMPLE_BRANCH_HW_INDEX), >> BRANCH_OPT("priv", PERF_SAMPLE_BRANCH_PRIV_SAVE), >> + BRANCH_OPT("counter", PERF_SAMPLE_BRANCH_COUNTERS), >> BRANCH_END >> }; >> >> diff --git a/tools/perf/util/perf_event_attr_fprintf.c b/tools/perf/util/perf_event_attr_fprintf.c >> index 2247991451f3..8f04d3b7f3ec 100644 >> --- a/tools/perf/util/perf_event_attr_fprintf.c >> +++ b/tools/perf/util/perf_event_attr_fprintf.c >> @@ -55,6 +55,7 @@ static void __p_branch_sample_type(char *buf, size_t size, u64 value) >> bit_name(COND), bit_name(CALL_STACK), bit_name(IND_JUMP), >> bit_name(CALL), bit_name(NO_FLAGS), bit_name(NO_CYCLES), >> bit_name(TYPE_SAVE), bit_name(HW_INDEX), bit_name(PRIV_SAVE), >> + bit_name(COUNTERS), >> { .name = NULL, } >> }; >> #undef bit_name >> diff --git a/tools/perf/util/sample.h b/tools/perf/util/sample.h >> index c92ad0f51ecd..70b2c3135555 100644 >> --- a/tools/perf/util/sample.h >> +++ b/tools/perf/util/sample.h >> @@ -113,6 +113,7 @@ struct perf_sample { >> void *raw_data; >> struct ip_callchain *callchain; >> struct branch_stack *branch_stack; >> + u64 *branch_stack_cntr; >> struct regs_dump user_regs; >> struct regs_dump intr_regs; >> struct stack_dump user_stack; >> diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c >> index 1e9aa8ed15b6..4a094ab0362b 100644 >> --- a/tools/perf/util/session.c >> +++ b/tools/perf/util/session.c >> @@ -1150,9 +1150,13 @@ static void callchain__printf(struct evsel *evsel, >> i, callchain->ips[i]); >> } >> >> -static void branch_stack__printf(struct perf_sample *sample, bool callstack) >> +static void branch_stack__printf(struct perf_sample *sample, >> + struct evsel *evsel) >> { >> struct branch_entry *entries = perf_sample__branch_entries(sample); >> + bool callstack = evsel__has_branch_callstack(evsel); >> + u64 *branch_stack_cntr = sample->branch_stack_cntr; >> + struct perf_env *env = evsel__env(evsel); >> uint64_t i; >> >> if (!callstack) { >> @@ -1194,6 +1198,13 @@ static void branch_stack__printf(struct perf_sample *sample, bool callstack) >> } >> } >> } >> + >> + if (branch_stack_cntr) { >> + printf("... branch stack counters: nr:%" PRIu64 " (counter width: %u max counter nr:%u)\n", >> + sample->branch_stack->nr, env->br_cntr_width, env->br_cntr_nr); >> + for (i = 0; i < sample->branch_stack->nr; i++) >> + printf("..... %2"PRIu64": %016" PRIx64 "\n", i, branch_stack_cntr[i]); >> + } >> } >> >> static void regs_dump__printf(u64 mask, u64 *regs, const char *arch) >> @@ -1355,7 +1366,7 @@ static void dump_sample(struct evsel *evsel, union perf_event *event, >> callchain__printf(evsel, sample); >> >> if (evsel__has_br_stack(evsel)) >> - branch_stack__printf(sample, evsel__has_branch_callstack(evsel)); >> + branch_stack__printf(sample, evsel); >> >> if (sample_type & PERF_SAMPLE_REGS_USER) >> regs_user__printf(sample, arch); >> -- >> 2.35.1 >>