sdk/platform-tools/systrace/catapult/telemetry/telemetry/internal/platform/profiler/sample_profiler.py

   1 # Copyright 2013 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 signal
   6 import subprocess
   7 import sys
   8 import tempfile
   9
  10 from telemetry.core import exceptions
  11 from telemetry.internal.platform import profiler
  12
  13 import py_utils
  14
  15
  16 class _SingleProcessSampleProfiler(object):
  17   """An internal class for using iprofiler for a given process."""
  18   def __init__(self, pid, output_path):
  19     self._output_path = output_path
  20     self._tmp_output_file = tempfile.NamedTemporaryFile('w', 0)
  21     self._proc = subprocess.Popen(
  22         ['sample', str(pid), '-mayDie', '-file', self._output_path],
  23         stdout=self._tmp_output_file, stderr=subprocess.STDOUT)
  24     def IsStarted():
  25       stdout = self._GetStdOut()
  26       if 'sample cannot examine process' in stdout:
  27         raise exceptions.ProfilingException(
  28             'Failed to start sample for process %s\n' %
  29             self._output_path.split('.')[1])
  30       return 'Sampling process' in stdout
  31     py_utils.WaitFor(IsStarted, 120)
  32
  33   def CollectProfile(self):
  34     self._proc.send_signal(signal.SIGINT)
  35     exit_code = self._proc.wait()
  36     try:
  37       if exit_code:
  38         raise Exception(
  39             'sample failed with exit code %d. Output:\n%s' % (
  40             exit_code, self._GetStdOut()))
  41     finally:
  42       self._proc = None
  43       self._tmp_output_file.close()
  44
  45     print 'To view the profile, run:'
  46     print '  open -a TextEdit %s' % self._output_path
  47
  48     return self._output_path
  49
  50   def _GetStdOut(self):
  51     self._tmp_output_file.flush()
  52     try:
  53       with open(self._tmp_output_file.name) as f:
  54         return f.read()
  55     except IOError:
  56       return ''
  57
  58
  59 class SampleProfiler(profiler.Profiler):
  60
  61   def __init__(self, browser_backend, platform_backend, output_path, state):
  62     super(SampleProfiler, self).__init__(
  63         browser_backend, platform_backend, output_path, state)
  64     process_output_file_map = self._GetProcessOutputFileMap()
  65     self._process_profilers = []
  66     for pid, output_file in process_output_file_map.iteritems():
  67       if '.utility' in output_file:
  68         # The utility process may not have been started by Telemetry.
  69         # So we won't have permissing to profile it
  70         continue
  71       self._process_profilers.append(
  72           _SingleProcessSampleProfiler(pid, output_file))
  73
  74   @classmethod
  75   def name(cls):
  76     return 'sample'
  77
  78   @classmethod
  79   def is_supported(cls, browser_type):
  80     if sys.platform != 'darwin':
  81       return False
  82     if browser_type == 'any':
  83       return True
  84     return (not browser_type.startswith('android') and
  85             not browser_type.startswith('cros'))
  86
  87   def CollectProfile(self):
  88     output_paths = []
  89     for single_process in self._process_profilers:
  90       output_paths.append(single_process.CollectProfile())
  91     return output_paths