Trigger deadline immediately after an aborted main thread commit

cc/scheduler/scheduler_state_machine.cc

 // Copyright 2011 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.
 
 #include "cc/scheduler/scheduler_state_machine.h"
 
 #include "base/format_macros.h"
 #include "base/logging.h"
 #include "base/strings/stringprintf.h"
 #include "base/values.h"
@@ skipping 863 matching lines @@
   begin_frame_state_ = BEGIN_FRAME_STATE_IDLE;
 }
 
 bool SchedulerStateMachine::ShouldTriggerBeginFrameDeadlineEarly() const {
   // If we are in the middle of the readback, we won't swap, so there is
   // no reason to trigger the deadline early.
   if (readback_state_ != READBACK_STATE_IDLE)
     return false;
 
   // TODO(brianderson): This should take into account multiple commit sources.
-  return begin_frame_state_ == BEGIN_FRAME_STATE_INSIDE_BEGIN_FRAME &&
-         active_tree_needs_first_draw_;
+  if (begin_frame_state_ == BEGIN_FRAME_STATE_INSIDE_BEGIN_FRAME &&
+      active_tree_needs_first_draw_)
+    return true;

[brianderson, 2013/10/15 15:02:32]

Sorry, I meant to split this into two conditions:

if (begin_frame_state_ != BEGIN_FRAME_STATE_INSIDE_BEGIN_FRAME)
  return false;

if (active_tree_needs_first_draw_)
  return true;

That way, the whole method will not return true if there isn't a deadline
already pending.

[Sami, 2013/10/15 15:12:51]

Done.

+
+  // This is used to prioritize impl-thread draws when the main thread isn't
+  // producing anything, e.g., after an aborted commit. We also check that we
+  // don't have a pending tree -- otherwise we should give it a chance to
+  // activate.
+  // TODO(skyostil): Revisit this when we have more accurate deadline estimates.
+  if (commit_state_ == COMMIT_STATE_IDLE && needs_redraw_ && !has_pending_tree_)
+    return true;
+
+  return false;
 }
 
 void SchedulerStateMachine::DidEnterPollForAnticipatedDrawTriggers() {
   current_frame_number_++;
   inside_poll_for_anticipated_draw_triggers_ = true;
 }
 
 void SchedulerStateMachine::DidLeavePollForAnticipatedDrawTriggers() {
   inside_poll_for_anticipated_draw_triggers_ = false;
 }
@@ skipping 107 matching lines @@
     case OUTPUT_SURFACE_ACTIVE:
     case OUTPUT_SURFACE_WAITING_FOR_FIRST_COMMIT:
     case OUTPUT_SURFACE_WAITING_FOR_FIRST_ACTIVATION:
       return true;
   }
   NOTREACHED();
   return false;
 }
 
 }  // namespace cc