tools/profile_chrome/chrome_startup_controller.py

   1 # Copyright 2015 The Chromium Authors. All rights reserved.
   2 # Use of this source code is governed by a BSD-style license that can be
   3 # found in the LICENSE file.
   4
   5 import os
   6 import re
   7 import time
   8
   9 from pylib import flag_changer
  10 from pylib.perf import cache_control
  11
  12 from profile_chrome import controllers
  13
  14 class ChromeStartupTracingController(controllers.BaseController):
  15   def __init__(self, device, package_info, cold, url):
  16     self._device = device
  17     self._package_info = package_info
  18     self._cold = cold
  19     self._url = url
  20     self._trace_file = None
  21     self._trace_finish_re = re.compile(r' Completed startup tracing to (.*)')
  22     self._device.old_interface.StartMonitoringLogcat(clear=False)
  23
  24   def __repr__(self):
  25     return 'Browser Startup Trace'
  26
  27   def _SetupTracing(self):
  28     # TODO(lizeb): Figure out how to clean up the command-line file when
  29     # _TearDownTracing() is not executed in StopTracing().
  30     changer = flag_changer.FlagChanger(
  31         self._device, self._package_info.cmdline_file)
  32     changer.AddFlags(['--trace-startup'])
  33     self._device.old_interface.CloseApplication(self._package_info.package)
  34     if self._cold:
  35       self._device.old_interface.EnableAdbRoot()
  36       cache_control.CacheControl(self._device).DropRamCaches()
  37     self._device.old_interface.StartActivity(
  38         package=self._package_info.package,
  39         activity=self._package_info.activity,
  40         data=self._url,
  41         extras={'create_new_tab' : True})
  42
  43   def _TearDownTracing(self):
  44     changer = flag_changer.FlagChanger(
  45         self._device, self._package_info.cmdline_file)
  46     changer.RemoveFlags(['--trace-startup'])
  47
  48   def StartTracing(self, interval):
  49     self._SetupTracing()
  50     self._device.old_interface.SyncLogCat()
  51
  52   def StopTracing(self):
  53     try:
  54       self._trace_file = self._device.old_interface.WaitForLogMatch(
  55           self._trace_finish_re, None, timeout=10).group(1)
  56     finally:
  57       self._TearDownTracing()
  58
  59   def PullTrace(self):
  60     # Wait a bit for the browser to finish writing the trace file.
  61     time.sleep(3)
  62     trace_file = self._trace_file.replace('/storage/emulated/0/', '/sdcard/')
  63     host_file = os.path.join(os.path.curdir, os.path.basename(trace_file))
  64     self._device.PullFile(trace_file, host_file)
  65     return host_file