tools/perf/measurements/smooth_gesture_util.py

   1 # Copyright 2014 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 import copy
   5
   6 from telemetry.web_perf import timeline_interaction_record as tir_module
   7
   8
   9 def GetAdjustedInteractionIfContainGesture(timeline, interaction_record):
  10   """ Returns a new interaction record if interaction_record contains geture
  11   whose time range that overlaps with interaction_record's range. If not,
  12   returns a clone of original interaction_record.
  13   The synthetic gesture controller inserts a trace marker to precisely
  14   demarcate when the gesture was running. We check for overlap, not inclusion,
  15   because gesture_actions can start/end slightly outside the telemetry markers
  16   on Windows. This problem is probably caused by a race condition between
  17   the browser and renderer process submitting the trace events for the
  18   markers.
  19   """
  20   # Only adjust the range for gestures.
  21   if not interaction_record.label.startswith('Gesture_'):
  22     return copy.copy(interaction_record)
  23   gesture_events = [
  24     ev for ev
  25     in timeline.IterAllAsyncSlicesOfName('SyntheticGestureController::running')
  26     if ev.parent_slice is None and
  27     ev.start <= interaction_record.end and
  28     ev.end >= interaction_record.start]
  29   if len(gesture_events) == 0:
  30     return copy.copy(interaction_record)
  31   if len(gesture_events) > 1:
  32     raise Exception('More than one possible synthetic gesture marker found in '
  33                     'interaction_record %s.' % interaction_record.label)
  34   return tir_module.TimelineInteractionRecord(
  35     interaction_record.label, gesture_events[0].start,
  36     gesture_events[0].end, gesture_events[0],
  37     interaction_record._flags)  # pylint: disable=W0212