From nobody Mon May 25 04:34:00 2026 Received: from mail-dl1-f74.google.com (mail-dl1-f74.google.com [74.125.82.74]) (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 875083AC0E7 for ; Mon, 18 May 2026 22:22:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.82.74 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779142955; cv=none; b=l5thwH8GJwPRlbXxHWLJUqOveha8i5mp4ubXa/8FudIe60qTv6YM6zSkV6HDti7npTL3Z34zncJ1G0mRKMQDLJ5xIgJfNUHCul35r0OFzaLUsLynTVHVIbzwUfXbAltsidITbXSh9Dt6QrYKXyIy/rXSyL4o/kaEcL7Cj/5iVEE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779142955; c=relaxed/simple; bh=Dm1dRXMcj8LHggSUomlhbdBytPSZTwFogeXZK3/CgVE=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Content-Type; b=AR02WLrPp3/NgeVM2FUMwosSLR1k9FmWnNRtv2HDO44Mv4knAuq3626YRUXa16OAvGT1iaAkTqLu4H3hp7MldVm4q4mLoyxRUnsW+USlbdJ16Ug3hVR5Y7SQp0j7HmxHCo+qEEJUItjiEuNPx6zN3+SsttgpRZqK6qSMH5BVKoY= 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=aLNstwaF; arc=none smtp.client-ip=74.125.82.74 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="aLNstwaF" Received: by mail-dl1-f74.google.com with SMTP id a92af1059eb24-1353ac304f3so5143425c88.0 for ; Mon, 18 May 2026 15:22:34 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1779142954; x=1779747754; darn=vger.kernel.org; h=to:from:subject:message-id:references:mime-version:in-reply-to:date :from:to:cc:subject:date:message-id:reply-to; bh=rpNAlzgW5SSa1ZsBC1HKHkIDD3KLaNZAgkWCJbzVU4w=; b=aLNstwaF7hfN/VrUghmetjjL4iu0RB0HRppQN7ceM1wztPcn1rXHhlnJ6+6B1xz0mA zqvGUkjJm2kNn10efiacY4q/jfsaFuNX09wsHPcjm1rkVnbZDtPga84puiudWDaciDO/ 2fl6wibUSZxhnkKcAhhQgBR21kRE27svxTo78ig6k8vwWgcnfv6UvEOEvhCjyMgn5LKE ja0VUgkLEV3fEprHOOezY0x5GLBfxEXA5OVAivKaaEHsNzM1crti0PeqjU1E2HEI/Zr/ 19+hVr7zhSudbVbs0Hwm3dQpsQI18DyKrlMWgG0NPPooYk1SK/c6BCJMwqQitBVagWBq E0aw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1779142954; x=1779747754; h=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=oQAOVj4j+XF2A4mHzVjTzb2h6TN+rqhRy1+xxgDtfjafREBhCg5wOD8FfoMpvzZX79 ppFrSKLhmCiCvq3C6l7PRJeZJjQo4oaoBBCwnCiax0VgC2ySd1QukJtQkNXs+DmV4Rmj UXkoiQwWamSTJkM6ErbvMKqvwPlSCvoAUaCIoKGNI3g6UL3NSPFy+qbFmAWp0+MyumAU 17cONXGhsWcgM1gwfovePP8pi+X6OqsRxjxdor+gB8wHAAkFjQRIUS5gwSSs7zi7DF+3 7wW6OzDIVv/wuw/C3oMHO7okFfrDS8IcUAvEpQCyEgXZSUEK7Ys7MSwXgmxRF7L9Amqd 156Q== X-Forwarded-Encrypted: i=1; AFNElJ/zFWdas43SMe67PXS6njXyUd6T9Z1TKqIDXVyIxZrFf6TPVuKrWWSMn3GEm9ZCgLl0Vw94Qx2SZzbx+8o=@vger.kernel.org X-Gm-Message-State: AOJu0YzOchx0WRedLEhaRBWffEarUCMYeO6wCs3dRXbsW/DjQE01t+yr 1CaM5VGCG/BRPwjnzSTcUjlFPXKU9r6ycYN9P1ea6BHHupPaweauW4m4+yIkoDF672eMehiLMo2 Zi+sXdqMtAA== X-Received: from dlan21-n2.prod.google.com ([2002:a05:7022:eb55:20b0:132:8d92:4d72]) (user=irogers job=prod-delivery.src-stubby-dispatcher) by 2002:a05:7022:2586:b0:12c:856:ddcc with SMTP id a92af1059eb24-1350474133dmr7772190c88.27.1779142953579; Mon, 18 May 2026 15:22:33 -0700 (PDT) Date: Mon, 18 May 2026 15:22:27 -0700 In-Reply-To: <20260518222228.3027004-1-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> X-Mailer: git-send-email 2.54.0.631.ge1b05301d1-goog Message-ID: <20260518222228.3027004-2-irogers@google.com> Subject: [PATCH v1 1/2] perf stat: Propagate supported flag to follower cgroup BPF events From: Ian Rogers To: skanev@google.com, Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Namhyung Kim , Jiri Olsa , Ian Rogers , Adrian Hunter , James Clark , linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org 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-dl1-f73.google.com (mail-dl1-f73.google.com [74.125.82.73]) (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 AE8E33AA4E9 for ; Mon, 18 May 2026 22:22:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.82.73 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779142961; cv=none; b=RYEGMhqIsowti/DXL/KPerl7zQX++ZU1gthG44V3qLoxiUEw7AJ3FMMF+XXvIlB/eENWn1yMEQPwx9rRJnp2u+iN6E5Fvbv3+yGrPaQyWmT1YV8B63HJhfCPeupD7WPapQTpH1Fs7CoCvT8aMKFXk/YVtE4BMp2I2wSRTjK+M4I= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779142961; c=relaxed/simple; bh=o/Jnu6wD+9qxT0NVaY9TI9AByxz6RG/zhvND9invDHM=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Content-Type; b=SP0TFd8JpKibi0NiwBX4mLQw4YhUsMWwAOf2rFcxtxN0gL4M21ckscWIQB0QUaeKvzIZM/4M7th6ngkZv/pgZff80fB9MT/kIzRkgeJRQuXF/6lL0jrpBkaCT2MHdE+4PgJZobvbQhqyCMjfBJLJu51EMrDqsY6AtP61VsZ+fsU= 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=rx3vgZaZ; arc=none smtp.client-ip=74.125.82.73 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="rx3vgZaZ" Received: by mail-dl1-f73.google.com with SMTP id a92af1059eb24-130aab78a09so2791007c88.0 for ; Mon, 18 May 2026 15:22:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1779142956; x=1779747756; darn=vger.kernel.org; h=to:from:subject:message-id:references:mime-version:in-reply-to:date :from:to:cc:subject:date:message-id:reply-to; bh=cW1CzrqNtSbwXTcsUNpM10Pzm2IU0DaU1vPbneAeFro=; b=rx3vgZaZoI3xFvN3E0a+vaVtJXNH0CDeFv2d8VuiKylnZxXFLMGsOkwNc6nz4GEFMR ortcJsxL6SjI4Sul/xdqMgPdYo/lfi08BorInXyqkMiwyjeonnweoNFGdAxk3tk6oU6e d9rlvT+urnmoB5iXfnltzyLtXON827u5YjnRi53hmbPjRIo9AQJjCNpNTpf+aYyr8/bt 6DrE1TFIWrkQFVA8+WeRdxEz0P66U8zPBzmx/H+Cw6Ni0w5M5EP/0vF26csBTNFEwtxS /UTOXEM+hn+PnraDGcqqRAa6GtDS3J7Oy1tORKg77/tUdkzwIvJViY2812eW8cKqzkU+ o55Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1779142956; x=1779747756; h=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=cW1CzrqNtSbwXTcsUNpM10Pzm2IU0DaU1vPbneAeFro=; b=Zm7MeeIKeZt0bgqtR/yzKPj2d7pw8diVUdDPNpqAxg52RMvNMMr/7CsxFKAke5uGVK JRYOJvE2Qg+x4eagGnP1BnrJkVxJ6eT1zYN1jvhiZDbPxX4Eyf57vl55dllN9jC0POiC YGSejGkeIfBzohbm5B13/WoA70d3VWNEnsztQ1w0Bh6+lXT1Ic88C4Z/1RboxwAiqjgK JnGicTbwq24i6H10gbP9ln4w5Qhpt71PUeQoAITJTEPpnVVf8+I2M/EsraISU70GTKby V7c6fZhL6o2GsIkbKQnrPBOLFT2LcT8WeIPakvXw6T1RMBApxwBrYTqVFGO2MPxkyyWU MwKA== X-Forwarded-Encrypted: i=1; AFNElJ8MU/5XnPK11v+8qc6yVomTQ4CuFLVbDJ57SNBgivTgzQ2/Tu1MrK59gqMy5cuSxH26fp3P4JlbfiHe088=@vger.kernel.org X-Gm-Message-State: AOJu0YxABZKyJY5puIWbDNHB/XL0Z2/CNpnnJ5RymS3kZvFk+f9O7PMk dCSsROBWFeAezPjMQKZjWLcAzgw2QlbbC3wm3ySaye9TP0bvXQY1IzXufC38ukeyPnnG403rZsW oGsGDoYPadA== X-Received: from dled20-n1.prod.google.com ([2002:a05:701b:42d4:10b0:134:b6e7:5d22]) (user=irogers job=prod-delivery.src-stubby-dispatcher) by 2002:a05:7022:790:b0:133:598c:2b1a with SMTP id a92af1059eb24-13504a4fc9bmr8451628c88.41.1779142955614; Mon, 18 May 2026 15:22:35 -0700 (PDT) Date: Mon, 18 May 2026 15:22:28 -0700 In-Reply-To: <20260518222228.3027004-1-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> X-Mailer: git-send-email 2.54.0.631.ge1b05301d1-goog Message-ID: <20260518222228.3027004-3-irogers@google.com> Subject: [PATCH v1 2/2] perf test: Add stat metrics --for-each-cgroup test From: Ian Rogers To: skanev@google.com, Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Namhyung Kim , Jiri Olsa , Ian Rogers , Adrian Hunter , James Clark , linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org 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). - Checks if `insn_per_cycle` metric 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..4a29eb9a9067 --- /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 "${cgrp}" | grep "insn_per_cycle"= || true) + + if [ -z "${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