Force events to be non blocking if main thread is unresponsive.

third_party/WebKit/Source/platform/scheduler/renderer/renderer_scheduler_impl.h

 // 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.
 
 #ifndef THIRD_PARTY_WEBKIT_SOURCE_PLATFORM_SCHEDULER_RENDERER_RENDERER_SCHEDULER_IMPL_H_
 #define THIRD_PARTY_WEBKIT_SOURCE_PLATFORM_SCHEDULER_RENDERER_RENDERER_SCHEDULER_IMPL_H_
 
 #include "base/atomicops.h"
 #include "base/macros.h"
 #include "base/synchronization/lock.h"
+#include "device/base/synchronization/shared_memory_seqlock_buffer.h"
 #include "platform/scheduler/base/pollable_thread_safe_flag.h"
 #include "platform/scheduler/base/queueing_time_estimator.h"
 #include "platform/scheduler/base/thread_load_tracker.h"
 #include "platform/scheduler/child/idle_helper.h"
 #include "platform/scheduler/child/scheduler_helper.h"
 #include "platform/scheduler/renderer/deadline_task_runner.h"
 #include "platform/scheduler/renderer/idle_time_estimator.h"
 #include "platform/scheduler/renderer/render_widget_signals.h"
 #include "platform/scheduler/renderer/task_cost_estimator.h"
 #include "platform/scheduler/renderer/user_model.h"
@@ skipping 94 matching lines @@
   void AddTaskObserver(base::MessageLoop::TaskObserver* task_observer) override;
   void RemoveTaskObserver(
       base::MessageLoop::TaskObserver* task_observer) override;
   void Shutdown() override;
   void SuspendTimerQueue() override;
   void ResumeTimerQueue() override;
   void SetTimerQueueSuspensionWhenBackgroundedEnabled(bool enabled) override;
   void SetTopLevelBlameContext(
       base::trace_event::BlameContext* blame_context) override;
   void SetRAILModeObserver(RAILModeObserver* observer) override;
+  bool ShouldForceEventsNonBlockingForUnresponsiveMainThread() const override;
 
   // RenderWidgetSignals::Observer implementation:
   void SetAllRenderWidgetsHidden(bool hidden) override;
   void SetHasVisibleRenderWidgetWithTouchHandler(
       bool has_visible_render_widget_with_touch_handler) override;
 
   // SchedulerHelper::Observer implementation:
   void OnUnregisterTaskQueue(const scoped_refptr<TaskQueue>& queue) override;
   void OnTriedToExecuteBlockedTask(const TaskQueue& queue,
                                    const base::PendingTask& task) override;
 
   // TaskTimeObserver implementation:
-  void ReportTaskTime(TaskQueue* task_queue,
-                      double start_time,
-                      double end_time) override;
+  void ReportTaskStartTime(double start_time) override;
+  void ReportTaskEndTime(TaskQueue* task_queue,
+                         double start_time,
+                         double end_time) override;
 
   // QueueingTimeEstimator::Client implementation:
   void OnQueueingTimeForWindowEstimated(base::TimeDelta queueing_time) override;
 
   // Returns a task runner where tasks run at the highest possible priority.
   scoped_refptr<TaskQueue> ControlTaskRunner();
 
   void RegisterTimeDomain(TimeDomain* time_domain);
   void UnregisterTimeDomain(TimeDomain* time_domain);
 
@@ skipping 211 matching lines @@
   scoped_refptr<TaskQueue> default_timer_task_runner_;
 
   // Note |virtual_time_domain_| is lazily created.
   std::unique_ptr<AutoAdvancingVirtualTimeDomain> virtual_time_domain_;
 
   base::Closure update_policy_closure_;
   DeadlineTaskRunner delayed_update_policy_runner_;
   CancelableClosureHolder end_renderer_hidden_idle_period_closure_;
   CancelableClosureHolder suspend_timers_when_backgrounded_closure_;
 
+  using SeqLockQueueingTimeEstimator =
+      device::SharedMemorySeqLockBuffer<QueueingTimeEstimator>;
+
+  SeqLockQueueingTimeEstimator seqlock_queueing_time_estimator_;
+
   // We have decided to improve thread safety at the cost of some boilerplate
   // (the accessors) for the following data members.
 
   struct MainThreadOnly {
     MainThreadOnly(RendererSchedulerImpl* renderer_scheduler_impl,
                    const scoped_refptr<TaskQueue>& compositor_task_runner,
                    base::TickClock* time_source,
                    base::TimeTicks now);
     ~MainThreadOnly();
 
     TaskCostEstimator loading_task_cost_estimator;
     TaskCostEstimator timer_task_cost_estimator;
-    QueueingTimeEstimator queueing_time_estimator;
+    //    QueueingTimeEstimator queueing_time_estimator; // TODO
     IdleTimeEstimator idle_time_estimator;
     ThreadLoadTracker background_main_thread_load_tracker;
     ThreadLoadTracker foreground_main_thread_load_tracker;
     UseCase current_use_case;
     Policy current_policy;
     base::TimeTicks current_policy_expiration_time;
     base::TimeTicks estimated_next_frame_begin;
+    base::TimeTicks current_task_start_time;
     base::TimeDelta compositor_frame_interval;
     base::TimeDelta longest_jank_free_task_duration;
     int timer_queue_suspend_count;  // TIMER_TASK_QUEUE suspended if non-zero.
     int navigation_task_expected_count;
     ExpensiveTaskPolicy expensive_task_policy;
     bool renderer_hidden;
     bool renderer_backgrounded;
     bool renderer_suspended;
     bool timer_queue_suspension_when_backgrounded_enabled;
     bool timer_queue_suspended_when_backgrounded;
     bool was_shutdown;
     bool loading_tasks_seem_expensive;
     bool timer_tasks_seem_expensive;
     bool touchstart_expected_soon;
     bool have_seen_a_begin_main_frame;
     bool have_reported_blocking_intervention_in_current_policy;
     bool have_reported_blocking_intervention_since_navigation;
     bool has_visible_render_widget_with_touch_handler;
     bool begin_frame_not_expected_soon;
     bool in_idle_period_for_testing;
     bool use_virtual_time;
     std::set<WebViewSchedulerImpl*> web_view_schedulers;  // Not owned.
     RAILModeObserver* rail_mode_observer;                 // Not owned.
   };
 
   struct AnyThread {
-    AnyThread();
+    AnyThread(RendererSchedulerImpl* renderer_scheduler_impl);
     ~AnyThread();
 
     base::TimeTicks last_idle_period_end_time;
     base::TimeTicks rails_loading_priority_deadline;
     base::TimeTicks fling_compositor_escalation_deadline;
     UserModel user_model;
     bool awaiting_touch_start_response;
     bool in_idle_period;
     bool begin_main_frame_on_critical_path;
     bool last_gesture_was_compositor_driven;
@@ skipping 52 matching lines @@
   PollableThreadSafeFlag policy_may_need_update_;
   base::WeakPtrFactory<RendererSchedulerImpl> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(RendererSchedulerImpl);
 };
 
 }  // namespace scheduler
 }  // namespace blink
 
 #endif  // THIRD_PARTY_WEBKIT_SOURCE_PLATFORM_SCHEDULER_RENDERER_RENDERER_SCHEDULER_IMPL_H_