From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-dl1-f72.google.com (mail-dl1-f72.google.com [74.125.82.72]) (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 A077536A34F for ; Tue, 29 Sep 2026 02:19:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.82.72 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790648382; cv=none; b=BpIulRy9zUR5p8lB8jsmpzXQ8dNUP0Gqgy1IPwWg5xj6tnbkhOi+JQI3sE2rugUEqLHK0ozP0+9cfhjqZgf3Hr7t488Kf8LHQ4+CDWdOXdWtJ97nBq6tMCKLchWe6II+uN7o03gPjSkJda7sJjBs9UWpZWQ0DzRC6PMDAnESwow= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790648382; c=relaxed/simple; bh=MpATh6DLU98HScpCbcjE6wdxFQKiVZzWiibe6PodilY=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=P5z4o0kR9a+WooOlLekKRi27thzNsNCssbxynrlhiRkiY9LxbH6zZctmBpG77+eX4C/mjPF0p4j7Si3KbzGmIoX+fmcEsU9jm737dFSSiaKOINahfgMTpiWlzKX07ZipTwUSBLwv/6z9RidE57QpPovn+JXuojKTqA43ppqhBMI= 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=veg8JJrh; arc=none smtp.client-ip=74.125.82.72 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="veg8JJrh" Received: by mail-dl1-f72.google.com with SMTP id a92af1059eb24-147be78cd56so1605944c88.1 for ; Mon, 28 Sep 2026 19:19:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1790648380; x=1791253180; darn=vger.kernel.org; h=content-type:cc:to:from:subject:message-id:references:mime-version :in-reply-to:date:from:to:cc:subject:date:message-id:reply-to :content-type; bh=uYp7K70TA5ymSa0NZecpwuKiUmoP6HQAUKW4+jlj9sg=; b=veg8JJrhjXgkMgDql4rhW/79OuzPrrXbPF3XcLO1KwJTTybunGYh8Ek31/2vREdk9U kIXRzBq2nWu9+wGR1TtRves2UOYR1BGKxwDgUkJaKzS4blCJ6zJVXs/5u9LaJbI5jS3K iGGbva1gfbmZlLWSvV4Aj0KJtpqjuapxEoPssTO5W+3r6FtfIBpDGGE1HlAjt7W8M5OY zzhllm3i7fk8zDJVF9UasBwpHPE0WrimjCsc3YA3WhD9bJjq1rtJKViUU/8KJhpJH73k FahcsBmwzH7/usbt8Ww1EbBqmSKUJQcn3doKk2uTaRat3F1PGOMhRug3VahmS65J+paq eFxA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1790648380; x=1791253180; h=content-type: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:content-type; bh=uYp7K70TA5ymSa0NZecpwuKiUmoP6HQAUKW4+jlj9sg=; b=ls9Nj7UTaIKtdEvn2oUgixMMy9QUkbZ3qxjOdkLvh2K8Nje0T7NqAle6wQjda8ktz0 4WiRzMdS0HM4a4GCULr3nZd0aPysyPo02Juaskj+awkpBvEYIzEDyAPwoLMGZOkQfLPs 5DBwQRg3fiqpfs+uuI8V7gKMJD+d/UHjPSRMkSGVQugH9IR5Nur3yESjJDhgm1PeER4j rrxw4UfpTDvVbRszOGpfh2XU+JiQUvbXZgwMFuYZtOa+xa8EnAPSKgTvJck89SQZgCOh rqM75iwvxkc4AAOA8IWXOV5lcI7gHu/LP4FJRgFearGgBV/EkkZSu++WOh+OuYfFKAmv xngA== X-Forwarded-Encrypted: i=1; AKwUvByLToHCtFCj8bwoorM9rSpdt7c7NfZJbqQREKeEgzevcgTzwf1f00bhPC3/Aq+swWOI3+sqS+GrSGyldaA=@vger.kernel.org X-Gm-Message-State: AFuF++m+C5kNrxWadUJr6Q0eZyLWUEQlwiNVwyYelWLtQPDCGXpENPWG fQoRnrcp0s6oo7XsO11QLdoquCoSoaI6tBcsFJcQbGRlMD7mF0duGqFk38jDDIL70ohlONO9v3x 3KAOOGjGrpQ== X-Received: from dlbsv14.prod.google.com ([2002:a05:7022:3a0e:b0:144:fbc3:1059]) (user=irogers job=prod-delivery.src-stubby-dispatcher) by 2002:a05:701b:21db:b0:149:f2b3:ef78 with SMTP id a92af1059eb24-149f2b3f52dmr5684415c88.32.1790648379319; Mon, 28 Sep 2026 19:19:39 -0700 (PDT) Date: Mon, 28 Sep 2026 19:19:09 -0700 In-Reply-To: <20260929021913.56010-1-irogers@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260929021913.56010-1-irogers@google.com> X-Mailer: git-send-email 2.56.0.rc1.315.gc6ed9934b7-goog Message-ID: <20260929021913.56010-6-irogers@google.com> Subject: [PATCH v1 5/9] perf test: Deflake failed-syscalls Python shell tests under load From: Ian Rogers To: Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Namhyung Kim Cc: Jiri Olsa , Ian Rogers , Adrian Hunter , James Clark , linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" When running 'perf test' in parallel under heavy system load, a one-shot 'perf record -e ... -- ls /does_not_exist' without '-B -N --no-bpf-event' can exit in under 300 microseconds before 'ls's PERF_RECORD_COMM and ENOENT sys_exit events are captured, while also contending on ~/.debug build-id caching and BPF event synthesis. Pass '-B -N --no-bpf-event' to 'perf record', sleep 0.05s in a subshell after 'ls' so its events are flushed before the parent subshell exits, and wrap the record and check steps in a bounded retry loop (up to 5 attempts). Fixes: b76c43d09b06 ("perf python: Port failed-syscalls-by-pid to perf module") Fixes: 4e3fe6987cba ("perf python: Port failed-syscalls from Perl to perf module") Assisted-by: Antigravity:gemini-3.1-pro Signed-off-by: Ian Rogers --- .../test_failed_syscalls_by_pid_python.sh | 68 +++++++++++-------- .../shell/test_failed_syscalls_python.sh | 44 +++++++----- 2 files changed, 67 insertions(+), 45 deletions(-) diff --git a/tools/perf/tests/shell/test_failed_syscalls_by_pid_python.sh b/tools/perf/tests/shell/test_failed_syscalls_by_pid_python.sh index 215372d4e1c5..070a7ef6b8ad 100755 --- a/tools/perf/tests/shell/test_failed_syscalls_by_pid_python.sh +++ b/tools/perf/tests/shell/test_failed_syscalls_by_pid_python.sh @@ -41,8 +41,10 @@ test_file_mode() { echo "Testing failed-syscalls-by-pid.py..." # Check if syscalls:sys_exit is supported/readable - if ! perf record -e syscalls:sys_exit -o /dev/null -- true >/dev/null 2>&1; then - if ! perf record -e raw_syscalls:sys_exit -o /dev/null -- true >/dev/null 2>&1; then + if ! perf record -B -N --no-bpf-event -e syscalls:sys_exit \ + -o /dev/null -- true >/dev/null 2>&1; then + if ! perf record -B -N --no-bpf-event -e raw_syscalls:sys_exit \ + -o /dev/null -- true >/dev/null 2>&1; then echo "Skipping test, no syscalls:sys_exit or raw_syscalls:sys_exit event" exit 2 else @@ -52,41 +54,49 @@ test_file_mode() { EVENT="syscalls:sys_exit" fi - # Generate some events by running a command that should fail at least some syscall - # (e.g. failing stat on non-existent file). - # Using '|| true' because 'perf record' returns the exit code of 'ls', - # which fails with ENOENT - perf record -e "${EVENT}" -o "${temp_data}" -- ls /does_not_exist >/dev/null 2>&1 || true + # Generate some events by running a command that fails a syscall + # (e.g. failing stat on non-existent file), sleeping briefly in the + # subshell so ls's PERF_RECORD_COMM and sys_exit events are flushed. + passed=0 + for _ in 1 2 3 4 5; do + rm -f "${temp_data}" "${temp_out}" "${temp_out}.comm" "${temp_out}.pid" + perf record -B -N --no-bpf-event -e "${EVENT}" -o "${temp_data}" \ + -- sh -c "ls /does_not_exist 2>/dev/null; sleep 0.05 || true" \ + >/dev/null 2>&1 || true + if [ ! -s "${temp_data}" ]; then + continue + fi + + if perf script failed-syscalls-by-pid -i "${temp_data}" > "${temp_out}" && \ + grep -n -q "err = ENOENT" "${temp_out}" && \ + perf script failed-syscalls-by-pid -i "${temp_data}" \ + "ls" > "${temp_out}.comm" && \ + grep -q "err = ENOENT" "${temp_out}.comm"; then + ls_pid=$(sed -n 's/^ls \[\([0-9][0-9]*\)\].*/\1/p' \ + "${temp_out}.comm" | head -n 1) + if [ -n "${ls_pid}" ] && \ + perf script failed-syscalls-by-pid -i "${temp_data}" \ + "${ls_pid}" > "${temp_out}.pid" && \ + grep -q "err = ENOENT" "${temp_out}.pid"; then + passed=1 + break + fi + fi + done + if [ ! -s "${temp_data}" ]; then echo "Skipping test, perf record failed to create data" exit 2 fi - # Run the script and check output - if ! perf script failed-syscalls-by-pid -i "${temp_data}" > "${temp_out}"; then + if [ "$passed" -eq 0 ]; then echo "failed-syscalls-by-pid test failed." - err=1 - elif ! grep -n -q "err = ENOENT" "${temp_out}"; then - echo "Failed to find expected failed syscalls" - cat "${temp_out}" - err=1 - elif ! perf script failed-syscalls-by-pid -i "${temp_data}" "ls" > "${temp_out}.comm" || \ - ! grep -q "err = ENOENT" "${temp_out}.comm"; then - echo "failed-syscalls-by-pid comm filter test failed." - cat "${temp_out}.comm" + cat "${temp_out}" 2>/dev/null || true + cat "${temp_out}.comm" 2>/dev/null || true + cat "${temp_out}.pid" 2>/dev/null || true err=1 else - ls_pid=$(sed -n 's/^ls \[\([0-9][0-9]*\)\].*/\1/p' "${temp_out}.comm" | head -n 1) - if [ -z "${ls_pid}" ] || \ - ! perf script failed-syscalls-by-pid -i "${temp_data}" \ - "${ls_pid}" > "${temp_out}.pid" || \ - ! grep -q "err = ENOENT" "${temp_out}.pid"; then - echo "failed-syscalls-by-pid PID filter test failed." - cat "${temp_out}.pid" 2>/dev/null || true - err=1 - else - echo "failed-syscalls-by-pid test passed." - fi + echo "failed-syscalls-by-pid test passed." fi rm -f "${temp_out}" "${temp_out}.comm" "${temp_out}.pid" } diff --git a/tools/perf/tests/shell/test_failed_syscalls_python.sh b/tools/perf/tests/shell/test_failed_syscalls_python.sh index 861c2ba71c0a..88a42e3de4f3 100755 --- a/tools/perf/tests/shell/test_failed_syscalls_python.sh +++ b/tools/perf/tests/shell/test_failed_syscalls_python.sh @@ -41,8 +41,10 @@ temp_out=$(mktemp /tmp/perf.out.XXXXXX) echo "Testing failed-syscalls.py..." # Check if sys_exit event can be recorded -if ! perf record -e raw_syscalls:sys_exit -o /dev/null -- true >/dev/null 2>&1; then - if ! perf record -e syscalls:sys_exit -o /dev/null -- true >/dev/null 2>&1; then +if ! perf record -B -N --no-bpf-event -e raw_syscalls:sys_exit \ + -o /dev/null -- true >/dev/null 2>&1; then + if ! perf record -B -N --no-bpf-event -e syscalls:sys_exit \ + -o /dev/null -- true >/dev/null 2>&1; then echo "Skipping test, no permission or support for sys_exit event" exit 2 else @@ -52,28 +54,38 @@ else EVENT="raw_syscalls:sys_exit" fi -# Run perf record with a command that fails a syscall (ls non-existent file). -# ls exits with non-zero, so perf record returns non-zero exit code of the workload. -perf record -e "${EVENT}" -o "${temp_data}" \ - -- ls /nonexistent_file_for_test >/dev/null 2>&1 || true +# Run perf record with a command that fails a syscall (ls non-existent file), +# sleeping briefly in the subshell so ls's PERF_RECORD_COMM and sys_exit events are flushed. +passed=0 +for _ in 1 2 3 4 5; do + rm -f "${temp_data}" "${temp_out}" + perf record -B -N --no-bpf-event -e "${EVENT}" -o "${temp_data}" \ + -- sh -c "ls /nonexistent_file_for_test 2>/dev/null; sleep 0.05 || true" \ + >/dev/null 2>&1 || true + + if [ ! -s "${temp_data}" ]; then + continue + fi + + # Check that the script executes + if perf script failed-syscalls -i "${temp_data}" > "${temp_out}" && \ + grep -q "failed syscalls by comm" "${temp_out}" && \ + grep -Eq '^ls[[:space:]]+[0-9]+' "${temp_out}"; then + passed=1 + break + fi +done if [ ! -s "${temp_data}" ]; then echo "Skipping test, perf record failed to create data" exit 2 fi -# Check that the script executes -if ! perf script failed-syscalls -i "${temp_data}" > "${temp_out}"; then - echo "failed-syscalls.py test failed" +if [ "$passed" -eq 0 ]; then + echo "Failed to find the metrics table header or expected error" err=1 else - if ! grep -q "failed syscalls by comm" "${temp_out}" || \ - ! grep -Eq '^ls[[:space:]]+[0-9]+' "${temp_out}"; then - echo "Failed to find the metrics table header or expected error" - err=1 - else - echo "failed-syscalls test passed." - fi + echo "failed-syscalls test passed." fi rm -f "${temp_out}" -- 2.56.0.rc1.315.gc6ed9934b7-goog