From mboxrd@z Thu Jan 1 00:00:00 1970 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 1434A37B023 for ; Tue, 16 Jun 2026 01:16:34 +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=1781572596; cv=none; b=pt1UBawqrVR+GhOH6dTY5nk/7zi00HunDge9KA6IrYM6WlJL/xNSh6xZz45yfGK/fODhIvnbV2YCH1e+vL22qMwmS4TiAJyui30XLRMEcAoe9yWXe1sjNU7wGd/n44mu+/sIu+dQXr9aFPyys7+USJRDa0ryfUd/qP6/2jUI79g= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781572596; c=relaxed/simple; bh=4dLo4HpbrybbnBf8shD12wCKP55rLDF16HiWGceZngg=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=aWayZtVn3IM7CtXEh+z0mkcrCIadMRAS7Q5bm88pvdPm89kmCfdJQUPN9Yqyqa4QeMumv4lwgMFft+9O29/gHu9f72OvkxIdaryfxT9r3vpvgyLUwSHQukuu+I5tGc9sGScC6KaXlD6VhAY47B91IpCNyFMaUL3N66pB/qh8BSA= 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=iTAKdicw; 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="iTAKdicw" Received: by mail-dl1-f74.google.com with SMTP id a92af1059eb24-137fc6f8e9fso4081542c88.1 for ; Mon, 15 Jun 2026 18:16:34 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1781572594; x=1782177394; 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=4JIEJjPFYpgehV0e0DCUgUFbnCz0JdtZUpoEiWCHJq8=; b=iTAKdicwEdA7xOpk2ocimCtGyvvR2k9vjEtpvyXR02d/1KC8jDPcTjFGYnq2Rtry19 RuACQWb2zHpKyrx66qPbUB8S5SQZQ7BuZ0nPRAqIwerHITfKoNiUAXFWb0wtH6Zv4CwB xiADUTjOAoZJTj5iOZXIylxzfC5W+PU3qz/OSX3s6J66kHGqpqP+kFCgx5M8uVzyYn5D oS/gVbKi8H//wX/0JU/8Lbk2V7hQJPV4pozi+bxfTwE7PS4U2rtDtPYu7/3wuVuZzGrH gtDbF3yCeUWh6T/QRBp3axIcoSBbBiOzmy/QTRFkv2t5gcXGi8Ev+X6lWMITPtv7ufmI n5Fw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1781572594; x=1782177394; 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=4JIEJjPFYpgehV0e0DCUgUFbnCz0JdtZUpoEiWCHJq8=; b=JpSV4nYOIdYm7DrBu+s4xNoD2pZKak8YETaHEMVHpLl5sALQ/WjPBuMZvNl+/Sf9aj DSGCx1MmEEk+viN/98PFcDEqm2GRZXPRvbs23qKTtzUDe4hkqPkYO3LRkY8UAZXTyuEk p/gzbOK6qt3BYKsTZ4QloNs61z++9Gprisi76Epmfsu73w5NpYc9SK+wX+mprMycftBB HfTQ5hD5RDeEqbEs2TPSAg9EbAKQgbXiXSOCqmIr+gr5CTmoloRM10IrZCWeDBTu9fpu XYpK8J1u2+vbP4yzofIpz3faa/TBdqCCCs6m16Idy4jZR4ecMncnyFI9fehJEdT2QNJO 3fhg== X-Forwarded-Encrypted: i=1; AFNElJ8Oev9PdA6azHvjmSEU5QP6P6MTdEcb8JV0myhK1TYhLQktIIMFCGAwgcIu1edPHL5zUxNrIPLXyQRd7jQ=@vger.kernel.org X-Gm-Message-State: AOJu0Yyuo3RLSE9jxrKuM2H1wPHQ+aGZC/1xIlZdGNOLH3j2TL1vYaUX 4+Vb+PKN81CTvG/RuB+21pLln+aJ5qkxxD0psp0OxKvL3xatkiydGmLealAACbFF30T/4YuajoD pm/WzgMSl+A== X-Received: from dybff20.prod.google.com ([2002:a05:7300:bf14:b0:304:5761:e0e7]) (user=irogers job=prod-delivery.src-stubby-dispatcher) by 2002:a05:7022:991:b0:136:9ebf:3bf4 with SMTP id a92af1059eb24-13985f3338amr568239c88.26.1781572593938; Mon, 15 Jun 2026 18:16:33 -0700 (PDT) Date: Mon, 15 Jun 2026 18:15:43 -0700 In-Reply-To: <20260616011543.4037138-1-irogers@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260615223011.3873955-1-irogers@google.com> <20260616011543.4037138-1-irogers@google.com> X-Mailer: git-send-email 2.54.0.1136.gdb2ca164c4-goog Message-ID: <20260616011543.4037138-22-irogers@google.com> Subject: [PATCH v21 21/21] perf python: Add LiveSession helper From: Ian Rogers To: irogers@google.com, acme@kernel.org, namhyung@kernel.org Cc: adrian.hunter@intel.com, alice.mei.rogers@gmail.com, dapeng1.mi@linux.intel.com, james.clark@linaro.org, leo.yan@linux.dev, linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tmricht@linux.ibm.com Content-Type: text/plain; charset="UTF-8" Add LiveSession class in tools/perf/python/perf_live.py to support live event collection using perf.evlist and perf.parse_events, avoiding the need to fork a separate perf record process. Signed-off-by: Ian Rogers Assisted-by: Gemini:gemini-3.1-pro-preview --- tools/perf/python/perf_live.py | 59 ++++++++++++++++++++++ tools/perf/tests/shell/lib/setup_python.sh | 13 +++++ 2 files changed, 72 insertions(+) create mode 100755 tools/perf/python/perf_live.py diff --git a/tools/perf/python/perf_live.py b/tools/perf/python/perf_live.py new file mode 100755 index 000000000000..616b5f657463 --- /dev/null +++ b/tools/perf/python/perf_live.py @@ -0,0 +1,59 @@ +# SPDX-License-Identifier: GPL-2.0 +""" +Live event session helper using perf.evlist. + +This module provides a LiveSession class that allows running a callback +for each event collected live from the system, similar to perf.session +but without requiring a perf.data file. +""" + +import perf + + +class LiveSession: + """Represents a live event collection session.""" + + def __init__(self, event_string: str, sample_callback): + self.event_string = event_string + self.sample_callback = sample_callback + # Create a cpu map for all online CPUs + self.cpus = perf.cpu_map() + # Parse events and set maps + self.evlist = perf.parse_events(self.event_string, self.cpus) + self.evlist.config() + + def run(self): + """Run the live session.""" + try: + self.evlist.open() + self.evlist.mmap() + self.evlist.enable() + + while True: + # Poll for events with 100ms timeout + try: + self.evlist.poll(100) + except InterruptedError: + continue + for cpu in self.cpus: + for _ in range(1000): # Limit to 1000 events per CPU per poll to prevent starvation + try: + event = self.evlist.read_on_cpu(cpu) + except TypeError as e: + if "Unknown CPU" in str(e): + # CPU might be unmapped or offline, wait for mmap event + break + if "Unexpected header type" in str(e): + # Ignore valid but unsupported event types + continue + raise + + if event is None: + break + + if event.type == perf.RECORD_SAMPLE: + self.sample_callback(event) + except KeyboardInterrupt: + pass + finally: + self.evlist.close() diff --git a/tools/perf/tests/shell/lib/setup_python.sh b/tools/perf/tests/shell/lib/setup_python.sh index a58e5536f2ed..2173215a0517 100644 --- a/tools/perf/tests/shell/lib/setup_python.sh +++ b/tools/perf/tests/shell/lib/setup_python.sh @@ -14,3 +14,16 @@ then echo Skipping test, python not detected please set environment variable PYTHON. exit 2 fi + +# Set PYTHONPATH to find the in-tree built perf.so first, avoiding system-wide perf.so +if [ -n "$PERF_EXEC_PATH" ] && [ -d "$PERF_EXEC_PATH/python" ]; then + PYTHONPATH_DIR="$PERF_EXEC_PATH/python" +elif [ -d "$(dirname "$0")/../../python" ]; then + PYTHONPATH_DIR="$(dirname "$0")/../../python" +elif [ -d "$(dirname "$0")/../python" ]; then + PYTHONPATH_DIR="$(dirname "$0")/../python" +fi + +if [ -n "$PYTHONPATH_DIR" ]; then + export PYTHONPATH="$PYTHONPATH_DIR${PYTHONPATH:+:$PYTHONPATH}" +fi -- 2.54.0.1136.gdb2ca164c4-goog