Tab Switching Benchmark for ChromeOS

tools/perf/contrib/cros_benchmarks/cros_utils.py

+# Copyright 2017 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 json
+import logging
+import os
+import subprocess
+import time
+
+import py_utils
+
+from telemetry.core import exceptions
+from telemetry.value import histogram_util
+
+def RunRemoteCommand(dut_ip, cmd):
+  os.system('ssh root@%s %s' % (dut_ip, cmd))
+
+def GetTabSwitchHistogram(tab):
+  histogram_name = 'MPArch.RWH_TabSwitchPaintDuration'
+  histogram_type = histogram_util.BROWSER_HISTOGRAM
+  return histogram_util.GetHistogram(
+      histogram_type, histogram_name, tab)
+
+def GetTabSwitchHistogramRetry(browser):
+  """Retry GetHistogram() as it may fail when a context was discarded."""
+  while True:
+    try:
+      # Any tab can be used to get the TabSwitchPaintDuration histogram.
+      # At each retry, try to get valid context again.
+      return GetTabSwitchHistogram(browser.tabs[-1])
+    except exceptions.DevtoolsTargetCrashException:
+      logging.info('GetHistogram: devtools context lost')
+    except KeyError:
+      logging.info('GetHistogram: devtools context lost')
+    except Exception as e:
+      logging.warning('GetHistogram: exception')
+      logging.warning(e)
+    time.sleep(0.5)
+
+def WaitTabSwitching(browser, prev_histogram):
+  """Checking the histogram to wait for tab switching completion."""
+  def _IsDone():
+    cur_histogram = GetTabSwitchHistogramRetry(browser)
+
+    diff_histogram = histogram_util.SubtractHistogram(cur_histogram,
+                            prev_histogram)
+    diff_histogram_count = json.loads(diff_histogram).get('count', 0)
+    return diff_histogram_count > 0
+
+  try:
+    py_utils.WaitFor(_IsDone, 10)
+  except py_utils.TimeoutException:
+    logging.warning('wait for histogram timed out')
+
+class KeyboardEmulator(object):
+  def __init__(self, dut_ip):
+    self._dut_ip = dut_ip
+    self._process = None
+    self._key_device_name = None
+
+  def _SetupKeyDispatch(self, device_name):
+    """Uploading the script to send key to switch tabs."""
+    cur_dir = os.path.dirname(os.path.abspath(__file__))
+    send_key_filename = cur_dir + '/data/send_key_tab_switch'
+    log_key_filename = cur_dir + '/data/log_key_tab_switch'
+
+    send_key_content = '#!/bin/bash\n'
+    send_key_content += ('evemu-play --insert-slot0 ' + device_name +
+                       ' < /home/root/log_key_tab_switch')
+    with open(send_key_filename, 'w') as f:
+      f.write(send_key_content)
+    os.chmod(send_key_filename, 0774)
+
+    os.system('scp -q %s root@%s:/usr/local/tmp/' %
+              (log_key_filename, self._dut_ip))
+    os.system('scp -q %s root@%s:/usr/local/tmp/' %
+              (send_key_filename, self._dut_ip))
+
+  def __enter__(self):
+    cmd =  ['ssh', 'root@' + self._dut_ip, 'evemu-device',
+            '/usr/local/autotest/cros/input_playback/keyboard.prop']

[cywang, 2017/05/23 02:56:57]

LGTM in keyboard emulation, please make sure if the property file exists in case
there is any refactor in autotest repo.

[vovoy, 2017/05/23 03:24:09]

Done. Added checks to through exception if the property file doesn't exist.

+    self._process = subprocess.Popen(cmd, stdout=subprocess.PIPE)
+
+    # The evemu-device output format:
+    # Emulated Keyboard: /dev/input/event10
+    output = self._process.stdout.readline()
+    self._key_device_name = output.split()[2]
+    self._SetupKeyDispatch(self._key_device_name)
+    return self
+
+  def SwitchTab(self):
+    """Sending Ctrl-tab key to trigger tab switching."""
+    RunRemoteCommand(self._dut_ip, '/usr/local/tmp/send_key_tab_switch')
+
+  def __exit__(self, exc_type, exc_value, traceback):
+    # The remote process would live when the ssh process was terminated.
+    # Need to kill it explicitly.
+    self._process.kill()
+    RunRemoteCommand(self._dut_ip, 'pkill evemu-device')
+
+
+def NoScreenOff(dut_ip):
+  """Set screen off and dim timer to 1 hour."""
+  RunRemoteCommand(dut_ip, 'set_power_policy --ac_screen_off_delay=3600')
+  RunRemoteCommand(dut_ip, 'set_power_policy --ac_screen_dim_delay=3600')