# Copyright (c) 2011 The Chromium OS Authors. All rights reserved. # Use of this source code is governed by a BSD-style license that can be # found in the LICENSE file. """ This is a profiler class for the perf profiler in ChromeOS. It differs from the existing perf profiler in autotset by directly substituting the options passed to the initialize function into the "perf" command line. It allows one to specify which perf command to run and thus what type of profile to collect (e.g. "perf record" or "perf stat"). It also does not produce a perf report on the client (where there are no debug symbols) but instead copies the perf.data file back to the server for analysis. """ import os, signal, subprocess import threading, time import shutil import logging from autotest_lib.client.bin import profiler from autotest_lib.client.common_lib import error class cros_perf(profiler.profiler): """ Profiler for running perf """ version = 1 def initialize(self, interval=120, duration=10, profile_type='record'): """Initializes the cros perf profiler. Args: interval (int): How often to start the profiler duration (int): How long the profiler will run per interval. Set to None to run for the full duration of the test. profile_type (str): Profile type to run. Valid options: record, and stat. """ self.interval = interval self.duration = duration self.profile_type = profile_type if self.profile_type not in ['record', 'stat']: raise error.AutotestError( 'Unknown profile type: %s' % (profile_type)) def start(self, test): # KASLR makes looking up the symbols from the binary impossible, save # the running symbols. shutil.copy('/proc/kallsyms', test.profdir) self.thread = MonitorThread( interval=self.interval, duration=self.duration, profile_type=self.profile_type, test=test) self.thread.start() def stop(self, test): self.thread.stop() class MonitorThread(threading.Thread): """ Thread that runs perf at the specified interval and duration """ def __init__(self, interval, duration, profile_type, test): threading.Thread.__init__(self) self.stopped = threading.Event() self.interval = interval self.duration = duration self.profile_type = profile_type self.test = test def _get_command(self, timestamp): file_name = 'perf-%s.data' % (int(timestamp)) path = os.path.join(self.test.profdir, file_name) if self.profile_type == 'record': return ['perf', 'record', '-e', 'cycles', '-g', '--output', path] elif self.profile_type == 'stat': return ['perf', 'stat', 'record', '-a', '--output', path] else: raise error.AutotestError( 'Unknown profile type: %s' % (self.profile_type)) def run(self): logging.info("perf thread starting") sleep_time = 0 while not self.stopped.wait(sleep_time): start_time = time.time() cmd = self._get_command(start_time) logging.info("Running perf: %s", cmd) process = subprocess.Popen(cmd, close_fds=True) logging.info("Sleeping for %ss", self.duration) self.stopped.wait(self.duration) ret_code = process.poll() if ret_code is None: logging.info("Stopping perf") process.send_signal(signal.SIGINT) process.wait() else: logging.info( 'perf terminated early with return code: %d. ' 'Please check your logs.', ret_code) end_time = time.time() sleep_time = self.interval - (end_time - start_time) if sleep_time < 0: sleep_time = 0 def stop(self): """ Stops the thread """ logging.info("Stopping perf thread") self.stopped.set() self.join() logging.info("perf thread stopped")