From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-dl1-f69.google.com (mail-dl1-f69.google.com [74.125.82.69]) (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 8A23242FCAC for ; Tue, 29 Sep 2026 06:29:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.82.69 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790663393; cv=none; b=WKQo7OvPtu2tHatTYF9t1N0icDa7s8Y5m5dhW9TJiXW+XcrMLJf5NzKYeLMedpJ2ZC/P6OqBPQuZ8leb0FXTXJ0MxhoI0K70M+BeRczj5FvROZH2mFrpDoSpa5FZtlVm/KLbvqUfcPXpTS6EgqO5Ny7IpDHdgGfl2u9Z2yarAPc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790663393; c=relaxed/simple; bh=9dnCnm0obUdo2EqOcPv85Krg2CWY6/1fPUxNbupSKAU=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=mhaxv/FXWfA+24yg3i3SL0SrN84tdC3zMbnG+S/lgvkwNRP5BY2PRmN9RvECUNPd5hrgnB0qrxrg1ihWENF42jwtS97HoS4umNCRNs57mYSw45MN1vQfsH7lHaiU5HLN5i4iWLUX5GMwiNnmA8HSN1wn3h740QjMsIQLPLo7HkM= 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=K/uZ5Kzb; arc=none smtp.client-ip=74.125.82.69 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="K/uZ5Kzb" Received: by mail-dl1-f69.google.com with SMTP id a92af1059eb24-1384427c3efso5846425c88.0 for ; Mon, 28 Sep 2026 23:29:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1790663390; x=1791268190; 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=dnibIJ+lZBQ1CeVh0g9DN0YYOUBh+70fdfgpvSaop2o=; b=K/uZ5KzbV/jq0+d8Pjzng9cSPShP+6vy/hmT2kHBFdsD97P3ZxmyjKmQejnBlzhcz3 1r+N/IKSR5ssyIL/HbbEQn2F+A5k+qXhkCoL0I6eqKZhFE7mFhdXc71BNv7waGu4tpv3 teZD7yaCbjfotlV/OH+jySeMKuOf7DfBu97xUxwm/jHHdYd9kUOtTSSjG6QvvUvsPXfH 8VRW8DAJelq4DcbyxQW98jDfDTBMQnjuE5S7OQQNXZgpsIMo9xe79epNZLxNDjzFGipN F/XN3w8lgzckj5qhoTv05OvXtIXqSgWy4fGo0hX2+iQl6tBAhnACVLVAKXcuiIqwPyHN faGQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1790663390; x=1791268190; 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=dnibIJ+lZBQ1CeVh0g9DN0YYOUBh+70fdfgpvSaop2o=; b=upil6Xmxf237rMOEnZVKz5UaHR8fpgKKEgaP+lOSJp9zt9gbciVtdAtkSBkqrjG+1W ut4LbtjzKYSM0kdOdQH1jOzwkmD0cPoP2dmQZjvbNkIh9sQiE8phpczvD9gltU4K1r7I 7vttVyAJPMVB+YTsbQi3jpMaib+p/TyV6XtPYdLvx2yUUibq2NsEl6awzCz6iaASmav9 LcK5QB7udpf+UGMzbSElXYXyXf5fl//mSRlEEJ9plF+bgBDwZMmBGCA7Pgf+7fUmHinJ SgD211r1fgXt6Y08uqBaNmf73wUtgXm6qlIeEvT1t4521G9/PrEEQrDaefIue0ALzCg0 45TA== X-Forwarded-Encrypted: i=1; AKwUvBym/S6rLds0rlGKQ+bn/a9Jpf3xlALVyjW1tmuHhmqVM2jyzm40/QY4DJUfGlYq4fK6qIsTxYpA040OYODc/kzK@vger.kernel.org X-Gm-Message-State: AFuF++nZIPVeIUaJrZ9uJQ8Kh6gDuHbFR1NdqLZqVMlRIHYhVQE5c9dH ZZbuPil4I6VFTzZ3nZc+8GRrYMqyqu5mDUPQsm5Y+qkA1HEr91dHWTcL3+YSTpJdJop2LYV2LZy Lcae7PIuR4g== X-Received: from dlbox1.prod.google.com ([2002:a05:7022:1201:b0:144:bba4:7daa]) (user=irogers job=prod-delivery.src-stubby-dispatcher) by 2002:a05:7022:b044:10b0:147:9ad0:cf32 with SMTP id a92af1059eb24-1479ad0d333mr11842878c88.31.1790663389876; Mon, 28 Sep 2026 23:29:49 -0700 (PDT) Date: Mon, 28 Sep 2026 23:29:31 -0700 In-Reply-To: <20260929062937.374137-1-irogers@google.com> Precedence: bulk X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260929021913.56010-1-irogers@google.com> <20260929062937.374137-1-irogers@google.com> X-Mailer: git-send-email 2.56.0.rc1.315.gc6ed9934b7-goog Message-ID: <20260929062937.374137-4-irogers@google.com> Subject: [PATCH v2 3/9] perf python stat-cpi: Fix live mode signal races and test flakiness 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 Content-Type: text/plain; charset="UTF-8" In test_stat_cpi_python.sh, 'perf test -w noploop &' defaults to a 1-second duration and can exit under heavy parallel load before 'perf stat -p' and 'perf script stat-cpi' finish starting up. In addition, the fixed 'sleep 0.5' before sending SIGINT can fire before Python finishes importing the perf module, opening the live evlist, and flushing the first interval. In stat-cpi.py, register SIGINT and SIGTERM handlers before calling _open_live_evlist() and pass flush=True when printing live output so redirected stdout is flushed immediately after each interval. In test_stat_cpi_python.sh, run 'perf test -w noploop 60 &' so the target workload stays alive until killed, and poll the output file for 'cpi' (up to 5 seconds) before sending SIGINT. Fixes: 4425182d426b ("perf python: Port stat-cpi to perf module") Assisted-by: Antigravity:gemini-3.1-pro Signed-off-by: Ian Rogers --- tools/perf/python/stat-cpi.py | 19 ++++++++++--------- .../perf/tests/shell/test_stat_cpi_python.sh | 12 +++++++++--- 2 files changed, 19 insertions(+), 12 deletions(-) diff --git a/tools/perf/python/stat-cpi.py b/tools/perf/python/stat-cpi.py index 0b7d76876a6c..da92cf560067 100755 --- a/tools/perf/python/stat-cpi.py +++ b/tools/perf/python/stat-cpi.py @@ -106,7 +106,8 @@ class StatCpiAnalyzer: if ins != 0: cpi = cyc / float(ins) t_sec = timestamp / 1000000000.0 - print(f"{t_sec:15f}: cpu {cpu}, thread {thread} -> cpi {cpi:f} ({cyc:.0f}/{ins:.0f})") + print(f"{t_sec:15f}: cpu {cpu}, thread {thread} -> cpi {cpi:f} ({cyc:.0f}/{ins:.0f})", + flush=True) def read_counters(self, evlist: Any) -> None: """Read counters live.""" @@ -173,19 +174,19 @@ class StatCpiAnalyzer: def run_live(self) -> None: """Read counters live.""" - try: - evlist = self._open_live_evlist() - except OSError as e: - print(f"Failed to open events: {e}", file=sys.stderr) - sys.exit(1) - def handle_signal(_signum: int, _frame: Any) -> None: raise KeyboardInterrupt signal.signal(signal.SIGINT, signal.default_int_handler) signal.signal(signal.SIGTERM, handle_signal) - print("Live mode started. Press Ctrl+C to stop.") + try: + evlist = self._open_live_evlist() + except OSError as e: + print(f"Failed to open events: {e}", file=sys.stderr) + sys.exit(1) + + print("Live mode started. Press Ctrl+C to stop.", flush=True) try: while True: time.sleep(self.args.interval) @@ -195,7 +196,7 @@ class StatCpiAnalyzer: self.data.clear() self.recorded_pairs.clear() except KeyboardInterrupt: - print("\nStopped.") + print("\nStopped.", flush=True) finally: evlist.close() diff --git a/tools/perf/tests/shell/test_stat_cpi_python.sh b/tools/perf/tests/shell/test_stat_cpi_python.sh index fe7562307634..6cb376c92e2f 100755 --- a/tools/perf/tests/shell/test_stat_cpi_python.sh +++ b/tools/perf/tests/shell/test_stat_cpi_python.sh @@ -50,7 +50,7 @@ test_live_mode() { echo "perf stat failed (permissions?), skipping live mode test." return 0 fi - perf test -w noploop & + perf test -w noploop 60 & workload_pid=$! if ! perf stat -e cycles,instructions -p "$workload_pid" -- sleep 0.05 2>/dev/null && \ ! perf stat -e cycles:u,instructions:u -p "$workload_pid" -- sleep 0.05 2>/dev/null; then @@ -61,10 +61,16 @@ test_live_mode() { fi ran=1 - # Run live mode for 1 interval in the background, give it a tiny sleep, then interrupt + # Run live mode in the background, wait until at least one interval is + # printed, then interrupt. perf script stat-cpi -I 0.1 -p "$workload_pid" > "${temp_out}" & pid=$! - sleep 0.5 + for _ in $(seq 1 50); do + if grep -q "cpi" "${temp_out}"; then + break + fi + sleep 0.1 + done kill -INT "$pid" 2>/dev/null || true set +e wait "$pid" -- 2.56.0.rc1.315.gc6ed9934b7-goog