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
5import logging
6
7from telemetry.timeline import importer
8from telemetry.timeline import trace_data as trace_data_module
9
10class TraceBufferOverflowException(Exception):
11  pass
12
13
14class TabIdImporter(importer.TimelineImporter):
15  def __init__(self, model, trace_data):
16    # Needs to run after all other importers so overflow events have been
17    # created on the model.
18    super(TabIdImporter, self).__init__(
19        model,
20        trace_data,
21        import_order=999)
22    self._trace_data = trace_data
23
24  @staticmethod
25  def GetSupportedPart():
26    return trace_data_module.TAB_ID_PART
27
28  def ImportEvents(self):
29    pass
30
31  def FinalizeImport(self):
32    self._CheckTraceBufferOverflow()
33    self._CreateTabIdsToThreadsMap()
34
35  def _CheckTraceBufferOverflow(self):
36    # Since _CreateTabIdsToThreadsMap() relies on markers output on timeline
37    # tracing data, it may not work in case we have trace events dropped due to
38    # trace buffer overflow.
39    for process in self._model.GetAllProcesses():
40      if process.trace_buffer_did_overflow:
41        raise TraceBufferOverflowException(
42            'Trace buffer of process with pid=%d overflowed at timestamp %d. '
43            'Raw trace data:\n%s' %
44            (process.pid, process.trace_buffer_overflow_event.start,
45             repr(self._trace_data)))
46
47  def _CreateTabIdsToThreadsMap(self):
48    tab_id_events = self._trace_data.GetEventsFor(
49        trace_data_module.TAB_ID_PART)
50
51    for tab_id in tab_id_events:
52      try:
53        timeline_markers = self._model.FindTimelineMarkers(tab_id)
54      # If timeline_markers with name equals |tab_id| can't be found, it's
55      # non-fatal.
56      except Exception:
57        logging.warning('Cannot find timeline marker for tab with id=%s' %
58                        tab_id)
59        continue
60      assert len(timeline_markers) == 1
61      assert timeline_markers[0].start_thread == timeline_markers[0].end_thread
62      self._model.AddMappingFromTabIdToRendererThread(
63          tab_id, timeline_markers[0].start_thread)
64