Telemetry: Set scaling governor on all cpus (on all devices)

build/android/pylib/perf/perf_control_unittest.py

 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import os
 import sys
 import unittest
 
 sys.path.append(os.path.join(os.path.dirname(__file__), os.pardir, os.pardir))
 
 from pylib import android_commands
 from pylib.device import device_utils
 from pylib.perf import perf_control
 
-
 class TestPerfControl(unittest.TestCase):
   def setUp(self):
     if not os.getenv('BUILDTYPE'):
       os.environ['BUILDTYPE'] = 'Debug'
 
     devices = android_commands.GetAttachedDevices()
     self.assertGreater(len(devices), 0, 'No device attached!')
     self._device = device_utils.DeviceUtils(
         android_commands.AndroidCommands(device=devices[0]))
 
-  def testForceAllCpusOnline(self):
+  def testHighPerfMode(self):
     perf = perf_control.PerfControl(self._device)
-    cpu_online_files = self._device.RunShellCommand(
-        'ls -d /sys/devices/system/cpu/cpu[0-9]*/online')
     try:
-      perf.ForceAllCpusOnline(True)
-      for path in cpu_online_files:
+      perf.ForceHighPerfMode()

[pasko, 2014/06/19 17:48:32]

It was like that before, but this does not really look like a unittest if it
changes the state of the whole system.

ideally we would use something like telemetry.unittest.simple_mock to mock out
self._device.old_interface, but it can take some time.

Up to you.

[Sami, 2014/06/19 18:12:43]

Cue age old debate about integration vs. unit tests :) My opinion is that in
this case we actually want to frob the state of the device and make sure it
actually responded. This way we can catch problems with new devices that work
differently.

(BTW, AFAICT these tests aren't actually running on any bots -- probably should
fix that too :)

+      for cpu in range(perf.NumCpuCores()):
+        path = perf.CpuOnlineFormat() % cpu
         self.assertEquals('1',
                           self._device.old_interface.GetFileContents(path)[0])
-        mode = self._device.RunShellCommand('ls -l %s' % path)[0]
-        self.assertEquals('-r--r--r--', mode[:10])
+        path = perf.ScalingGovernorFormat() % cpu
+        self.assertEquals('performance',
+                          self._device.old_interface.GetFileContents(path)[0])
     finally:
-      perf.ForceAllCpusOnline(False)
-
-    for path in cpu_online_files:
-      mode = self._device.RunShellCommand('ls -l %s' % path)[0]
-      self.assertEquals('-rw-r--r--', mode[:10])
-
+      perf.SetDefaultPerfMode()
 
 if __name__ == '__main__':
   unittest.main()