From nobody Mon May 25 04:34:00 2026 Received: from mail-dy1-f201.google.com (mail-dy1-f201.google.com [74.125.82.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 44BB32FB97B for ; Tue, 19 May 2026 01:51:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.82.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779155476; cv=none; b=ZhbUmz/dnf+KnQXu2GMmlzdpNTxuhp9J+ryMzlLXIHVcPOcJDzxU9YPxtL0sGY24pkPXVXYkHfbml1Q/QMQOgAENM3lLmI36HK9AfZwQLki7OgzFokQadQavBpZb6f4mKOeTVPkafbV2zuFwoZQkx4nBAG5fxo2clBiD1aHbFEE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779155476; c=relaxed/simple; bh=Dm1dRXMcj8LHggSUomlhbdBytPSZTwFogeXZK3/CgVE=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=g/bQc79jSkNCpzqU+ZZ9m+SJOWa/RbwtR6l2m1rYqYB2qP5+99UnOHZ+t89RPzjRh4Xou6sJ14TDK2uaqd9FYAWxd9o3h4NwpuPWYDkGU3sJ+y3zM1HyMCuglmLiPYRBTCbtB/uyF4qV4kXgEBzpibzi0DI6WFf4ze7cTOHgPoM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--irogers.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=bFFZOLnV; arc=none smtp.client-ip=74.125.82.201 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--irogers.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="bFFZOLnV" Received: by mail-dy1-f201.google.com with SMTP id 5a478bee46e88-2f2d983d109so12881194eec.0 for ; Mon, 18 May 2026 18:51:15 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1779155474; x=1779760274; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=rpNAlzgW5SSa1ZsBC1HKHkIDD3KLaNZAgkWCJbzVU4w=; b=bFFZOLnVxizylZqufuCgIvFuHO28bcWCxDm9rKhNfDm3MqAF0OH1oSoFs6oPT4VtNw NnJNhYPY6tbQgnawkeEm5t7T8YLj5zsGxSBWWc4gfSMIprhy2mJ+UtIGvsre5TS0KDPJ jVZ5hHSjHRSNkEIqAEJcthzlej0Dp++2KDnkz6XXLv0VsvX+sP8jREp0T44lwyhkwo0U e+YBxSV15dTxvX9aV9C0IVoGIr6IHCJNeC1vYhfxSg1hCkEPCv4zeyeYx6P8IzD9DZk+ KqKLfDzSkkG9TFSOiGRLKdCkwLN6Nj5NnbITD6lYBlKyOMO/gfgnKERYYd02FbHXpRGB 9B4A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1779155474; x=1779760274; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=rpNAlzgW5SSa1ZsBC1HKHkIDD3KLaNZAgkWCJbzVU4w=; b=UuzaHlz3eTK2i80hd0dSUuy01Qp43BFgXmEkcm+p//8fBRBqgH2zSbRleF4QCtzlZs DhCcTFck6WZ8PPf2mOtKx3PCfCiXJVEECnBjkzLkxCX5K7lueBM0QSpKQVwU2qhx9+EG BtErntQMF/8aAVCAJOmCN65ztcyLWlkApkLJA2n/QqAPMD5QoyWp7E7ZkuJIzGthQmeL XArCUAWhy1wr78/YB8rzx6B3FZWsk/OPt5o47B63yDYr5bB1T3HBIFp+Eh5/LNAaJv0M swgaKRhFf/vRPIjytWQy2ox1RLSEE9bLGcVfUEE3w1c3VRPElEvSwDk+WkU4JeFP7up+ 2PIw== X-Forwarded-Encrypted: i=1; AFNElJ+UBIWga7xUAs5i7qP5zuTM0ajj5aZgdBAfJCg1oFi1V7rPylcqHB/lE0353LkJ8krkKvHplcN2vBjWGIo=@vger.kernel.org X-Gm-Message-State: AOJu0YwA744SgyH/fnuFxjl0N+qe91G85lKlrOUV2dNoP/Icjpi3W3h0 qYyfhlC4bW+w5dvdK+S4zCLhjOfLgNG/ALiDmtTdq5w1wU5vKmi58aL9zIF9rmgweiA7ogdZ4j3 gaB8v8xXU6g== X-Received: from dybqf6.prod.google.com ([2002:a05:7301:6486:b0:2f2:3f95:c586]) (user=irogers job=prod-delivery.src-stubby-dispatcher) by 2002:a05:7301:6447:b0:2ed:6f94:9d9d with SMTP id 5a478bee46e88-3039816bacemr8358806eec.8.1779155474195; Mon, 18 May 2026 18:51:14 -0700 (PDT) Date: Mon, 18 May 2026 18:51:07 -0700 In-Reply-To: <20260519015108.3094513-1-irogers@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260518222228.3027004-1-irogers@google.com> <20260519015108.3094513-1-irogers@google.com> X-Mailer: git-send-email 2.54.0.631.ge1b05301d1-goog Message-ID: <20260519015108.3094513-2-irogers@google.com> Subject: [PATCH v2 1/2] perf stat: Propagate supported flag to follower cgroup BPF events From: Ian Rogers To: irogers@google.com, acme@kernel.org, namhyung@kernel.org Cc: adrian.hunter@intel.com, james.clark@linaro.org, jolsa@kernel.org, linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, skanev@google.com Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" When using BPF counters with cgroups, follower events (for cgroups other than the first one) are not opened. Because they are not opened, their `supported` flag was left as `false`. During metric calculation, `prepare_metric` checks if the event is supported. If it is not supported (like the follower events), it explicitly sets the value to `NAN`, which eventually causes the metric to be reported as `nan %`. Fix this by propagating the `supported` flag from the "leader" events (the ones opened for the first cgroup) to the "follower" events. Reported-by: Svilen Kanev Assisted-by: Antigravity:gemini-3-flash Signed-off-by: Ian Rogers --- tools/perf/util/bpf_counter_cgroup.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/tools/perf/util/bpf_counter_cgroup.c b/tools/perf/util/bpf_cou= nter_cgroup.c index 519fee3dc3d0..dd1851634087 100644 --- a/tools/perf/util/bpf_counter_cgroup.c +++ b/tools/perf/util/bpf_counter_cgroup.c @@ -186,6 +186,21 @@ static int bperf_load_program(struct evlist *evlist) i++; } =20 + /* + * Propagate supported flag from leaders to followers. Follower events + * are not opened, so their supported flag remains false. + */ + { + struct evsel *leader; + int num_events =3D evlist->core.nr_entries / nr_cgroups; + + evlist__for_each_entry(evlist, evsel) { + leader =3D evlist__find_evsel(evlist, evsel->core.idx % num_events); + if (leader) + evsel->supported =3D leader->supported; + } + } + /* * bperf uses BPF_PROG_TEST_RUN to get accurate reading. Check * whether the kernel support it --=20 2.54.0.631.ge1b05301d1-goog From nobody Mon May 25 04:34:00 2026 Received: from mail-dy1-f202.google.com (mail-dy1-f202.google.com [74.125.82.202]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3F655307AF0 for ; Tue, 19 May 2026 01:51:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.82.202 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779155478; cv=none; b=dNqP0MkHvmcF5qJHRYEBNxhNut2b8gtzSg/8PAOWDYKv6bUALyI4fy//5feyecRCjeSu9el7NEiFXtvzr+hZpQWtse8yAYmtG7ts4u1eEs5MCoWJD/JQ2gVgXhmqn0P8ccnfuOJwx8EgK9YKcBqrGkOgUu8gdUvqImUcUDu1kSQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779155478; c=relaxed/simple; bh=frpKGqBbCZCqt0hWhzPxF2kYt7qbNOhThme+iYf42KY=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=DcaB8J9Lu8NCJe95TkLVnuNkCcIqDVfJps2rIVwier4bqYpMuHpjLIIYKULNhpckt82XUaEuld+Kv1t8lrqpQ8Pr4Jbl1P5D0iANL4v8o2WInA96mVW8XL5zKhml9ILnJpTAX7hiB0tTnkBqXFvJIjao1Et8j/lWyV1u6jruESM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--irogers.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=TKDppBEo; arc=none smtp.client-ip=74.125.82.202 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--irogers.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="TKDppBEo" Received: by mail-dy1-f202.google.com with SMTP id 5a478bee46e88-2ee5b73c5f2so1656239eec.0 for ; Mon, 18 May 2026 18:51:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1779155476; x=1779760276; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=zVGDXUHhQDO1HqSBMoZiDiTOql87LxWaPwxH6I36Yng=; b=TKDppBEoU/Er++WEu1J+dOW1+coXr6Uf3nJ3j21ZUvAfc9K1JIXO7GmfA8DPFX9QFs Vs1nao5oUwpF2ehcfgyCBsuZqeDHu1L5IUIB0Px4O+/fV3P2yXL+huQCpW6tivzzeIpC 1d2v2+hJzbBA7jw4wqVfEWKZ8MVQk6ITnrqpmll3xUPcHyprtsK3ECxDRlGqBlzwF8tN piYR84gRJ3+kxHOegK1do5k4m5KJOMTqeTblij8WIYeaJvRD96k/tjZnVFinEqcOMzfY N02eR4+hQNIZvl+jXQK2tXPILjiPoLKcfELzJyRBeCH+01tv5AJQBsSF/e/yLopSCh9M 8OSA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1779155476; x=1779760276; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=zVGDXUHhQDO1HqSBMoZiDiTOql87LxWaPwxH6I36Yng=; b=Hd4HbfDbY9enrYaNZbnT9u41/LRiYKwKSqWkiOWLJemFLCUixIVFkKKDUB9qhh+KaD m3c4Yu2H5v4N30opTxWUPEij74M116HMXh0ANrWqdmnjOfqmU3MD8fLVFG8TETP3UxEk i4X7VUm5gpGzmJt0gSLNUKdovjppp+zO1EroSXaoCKem3bw9QgppF8c/+IiVaJKFVAft 95euT2lGHDs+2hGk8IYltrxaF4p2n3/PUNyoNpfinl2xZwEsSoalHvlu6jUbUAEQloV/ 3+gpokCPuNJ7jbXqcCdl5OdsFm44biYbZVN7KBMxWWk2cqSNAHHpfLgpsvRouupTQoHU XDOw== X-Forwarded-Encrypted: i=1; AFNElJ8kK9zMZRxeJxWVHWM1Div4G/HB2S1MZe1ihclJBX3i5QAsI+1sGDaBebNXDhzMmPws4e57Dd8935x2rM0=@vger.kernel.org X-Gm-Message-State: AOJu0YzyRgO3JZafikbVsqIAp62oz+fx/G2CuK691Y7L16UzolUf7NE8 8t8hE7H5bUXZ3nfve6Wh4rZgnf3kVDLtugm0eQQgMU62X1YT2Eus6eLgVhEI09cMBpKjsrFsYNG qP8H4sNsSYQ== X-Received: from dybrp22.prod.google.com ([2002:a05:7301:4616:b0:2e2:488c:4eba]) (user=irogers job=prod-delivery.src-stubby-dispatcher) by 2002:a05:7300:ec11:b0:2c5:b23e:48a6 with SMTP id 5a478bee46e88-303986a0862mr7736899eec.23.1779155476160; Mon, 18 May 2026 18:51:16 -0700 (PDT) Date: Mon, 18 May 2026 18:51:08 -0700 In-Reply-To: <20260519015108.3094513-1-irogers@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260518222228.3027004-1-irogers@google.com> <20260519015108.3094513-1-irogers@google.com> X-Mailer: git-send-email 2.54.0.631.ge1b05301d1-goog Message-ID: <20260519015108.3094513-3-irogers@google.com> Subject: [PATCH v2 2/2] perf test: Add stat metrics --for-each-cgroup test From: Ian Rogers To: irogers@google.com, acme@kernel.org, namhyung@kernel.org Cc: adrian.hunter@intel.com, james.clark@linaro.org, jolsa@kernel.org, linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, skanev@google.com Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Add a new shell test `stat_metrics_cgrp.sh` to verify metric reporting with `--for-each-cgroup`, both with and without `--bpf-counters`. The test: - Checks if system-wide monitoring is supported (skips if not). - Finds cgroups to test. - Runs `perf stat` with `insn_per_cycle` metric and verifies that the metric is reported for each cgroup and does not contain invalid values (like `nan` or `nested`) or empty values when counts are present. - Tests both standard mode and BPF counters mode (if supported). Assisted-by: Antigravity:gemini-3-flash Signed-off-by: Ian Rogers Reported-by: Svilen Kanev --- tools/perf/tests/shell/stat_metrics_cgrp.sh | 123 ++++++++++++++++++++ 1 file changed, 123 insertions(+) create mode 100755 tools/perf/tests/shell/stat_metrics_cgrp.sh diff --git a/tools/perf/tests/shell/stat_metrics_cgrp.sh b/tools/perf/tests= /shell/stat_metrics_cgrp.sh new file mode 100755 index 000000000000..2f74bd9e3f2e --- /dev/null +++ b/tools/perf/tests/shell/stat_metrics_cgrp.sh @@ -0,0 +1,123 @@ +#!/bin/bash +# perf stat metrics --for-each-cgroup test +# SPDX-License-Identifier: GPL-2.0 + +set -e + +test_cgroups=3D + +log_verbose() { + echo "$1" +} + +# skip if system-wide is not supported +check_system_wide() +{ + log_verbose "Checking system-wide..." + if ! perf stat -a -e instructions sleep 0.01 > /dev/null 2>&1 + then + log_verbose "Skipping: system-wide monitoring not supported" + exit 2 + fi +} + +# find two cgroups to measure +find_cgroups() +{ + log_verbose "Finding cgroups..." + # try usual systemd slices first + if [ -d /sys/fs/cgroup/system.slice ] && [ -d /sys/fs/cgroup/user.slice ] + then + test_cgroups=3D"system.slice,user.slice" + log_verbose "Found cgroups: ${test_cgroups}" + return + fi + + # try root and self cgroups + find_cgroups_self_cgrp=3D$(grep perf_event /proc/self/cgroup | cut -d: -f= 3) + if [ -z "${find_cgroups_self_cgrp}" ] + then + # cgroup v2 doesn't specify perf_event + find_cgroups_self_cgrp=3D$(grep ^0: /proc/self/cgroup | cut -d: -f3) + fi + + if [ -z "${find_cgroups_self_cgrp}" ] + then + test_cgroups=3D"/" + else + test_cgroups=3D"/,${find_cgroups_self_cgrp}" + fi + log_verbose "Found cgroups: ${test_cgroups}" +} + +# Check if metric is reported for each cgroup +# $1: extra options (e.g. --bpf-counters) +check_metric_reported() +{ + local opts=3D"$1" + local output + + log_verbose "Running check_metric_reported with opts '${opts}'..." + # Run perf stat + if ! output=3D$(perf stat -a ${opts} \ + --metrics=3Dinsn_per_cycle \ + --for-each-cgroup "${test_cgroups}" \ + -x, sleep 0.1 2>&1) + then + echo "FAIL: perf stat failed with exit code $?" + echo "Output: ${output}" + exit 1 + fi + + log_verbose "perf stat output:" + log_verbose "${output}" + + # Split test_cgroups by comma + IFS=3D',' read -r -a cgrps <<< "${test_cgroups}" + + for cgrp in "${cgrps[@]}"; do + # Find lines for this cgroup and metric + local cgrp_lines + cgrp_lines=3D$(echo "${output}" | grep -F "${cgrp}" | grep "insn_per_cyc= le" || true) + + if [ -z "${cgrp_lines}" ] + then + echo "FAIL: No metric lines found for cgroup '${cgrp}'" + exit 1 + fi + + # Check for nan or nested + if echo "${cgrp_lines}" | grep -q -i -E ",nan,|,nested," + then + echo "FAIL: Invalid metric value (nan/nested) for cgroup '${cgrp}'" + echo "Line: ${cgrp_lines}" + exit 1 + fi + # Check for empty metric value + if echo "${cgrp_lines}" | grep -q -E ",,[[:space:]]*[^,]*insn_per_cycle" + then + echo "FAIL: Empty metric value for cgroup '${cgrp}'" + echo "Line: ${cgrp_lines}" + exit 1 + fi + done + log_verbose "check_metric_reported passed for opts '${opts}'" +} + +check_system_wide +find_cgroups + +# Test 1: Without BPF counters +check_metric_reported "" + +# Test 2: With BPF counters (if supported) +log_verbose "Checking BPF support..." +if perf stat -a --bpf-counters --for-each-cgroup / true > /dev/null 2>&1 +then + log_verbose "BPF supported, running Test 2..." + check_metric_reported "--bpf-counters" +else + log_verbose "BPF not supported, skipping Test 2" +fi + +exit 0 --=20 2.54.0.631.ge1b05301d1-goog