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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