Reland "Add new latency_info for tracking browser composite time."

content/browser/renderer_host/render_widget_host_impl.cc

 // Copyright (c) 2012 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 "content/browser/renderer_host/render_widget_host_impl.h"
 
 #include <math.h>
 #include <set>
 #include <utility>
 
@@ skipping 73 matching lines @@
 using blink::WebKeyboardEvent;
 using blink::WebMouseEvent;
 using blink::WebMouseWheelEvent;
 using blink::WebTextDirection;
 
 namespace content {
 namespace {
 
 bool g_check_for_pending_resize_ack = true;
 
+const size_t kBrowserCompositeLatencyHistorySize = 60;
+const double kBrowserCompositeLatencyEstimationPercentile = 90.0;
+const double kBrowserCompositeLatencyEstimationSlack = 1.1;
+
 typedef std::pair<int32, int32> RenderWidgetHostID;
 typedef base::hash_map<RenderWidgetHostID, RenderWidgetHostImpl*>
     RoutingIDWidgetMap;
 base::LazyInstance<RoutingIDWidgetMap> g_routing_id_widget_map =
     LAZY_INSTANCE_INITIALIZER;
 
 int GetInputRouterViewFlagsFromCompositorFrameMetadata(
     const cc::CompositorFrameMetadata metadata) {
   int view_flags = InputRouter::VIEW_FLAGS_NONE;
 
@@ skipping 73 matching lines @@
       ignore_input_events_(false),
       input_method_active_(false),
       text_direction_updated_(false),
       text_direction_(blink::WebTextDirectionLeftToRight),
       text_direction_canceled_(false),
       suppress_next_char_events_(false),
       pending_mouse_lock_request_(false),
       allow_privileged_mouse_lock_(false),
       has_touch_handler_(false),
       next_browser_snapshot_id_(1),
+      browser_composite_latency_history_(kBrowserCompositeLatencyHistorySize),
       weak_factory_(this) {
   CHECK(delegate_);
   if (routing_id_ == MSG_ROUTING_NONE) {
     routing_id_ = process_->GetNextRoutingID();
     surface_id_ = GpuSurfaceTracker::Get()->AddSurfaceForRenderer(
         process_->GetID(),
         routing_id_);
   } else {
     // TODO(piman): This is a O(N) lookup, where we could forward the
     // information from the RenderWidgetHelper. The problem is that doing so
@@ skipping 1234 matching lines @@
   uint32 output_surface_id = get<0>(param);
   get<1>(param).AssignTo(frame.get());
   std::vector<IPC::Message> messages_to_deliver_with_frame;
   messages_to_deliver_with_frame.swap(get<2>(param));
 
   latency_tracker_.OnSwapCompositorFrame(&frame->metadata.latency_info);
 
   input_router_->OnViewUpdated(
       GetInputRouterViewFlagsFromCompositorFrameMetadata(frame->metadata));
 
+  for (auto& latency : frame->metadata.latency_info)
+    latency.AddLatencyNumber(ui::INPUT_EVENT_BROWSER_COMPOSITE_COMPONENT, 0, 0);
+
   if (view_) {
     view_->OnSwapCompositorFrame(output_surface_id, frame.Pass());
     view_->DidReceiveRendererFrame();
   } else {
     cc::CompositorFrameAck ack;
     if (frame->gl_frame_data) {
       ack.gl_frame_data = frame->gl_frame_data.Pass();
       ack.gl_frame_data->sync_point = 0;
     } else if (frame->delegated_frame_data) {
       cc::TransferableResource::ReturnResources(
@@ skipping 553 matching lines @@
         base::Bind(&RenderWidgetHostImpl::WindowSnapshotReachedScreen,
                    weak_factory_.GetWeakPtr(),
                    sequence_number),
         base::TimeDelta::FromSecondsD(1. / 6));
 #else
     WindowSnapshotReachedScreen(sequence_number);
 #endif
   }
 
   latency_tracker_.OnFrameSwapped(latency_info);
+
+  ui::LatencyInfo::LatencyComponent gpu_swap_component;
+  if (!latency_info.FindLatency(
+          ui::INPUT_EVENT_GPU_SWAP_BUFFER_COMPONENT, 0, &gpu_swap_component)) {
+    return;
+  }
+
+  ui::LatencyInfo::LatencyComponent composite_component;
+  if (latency_info.FindLatency(ui::INPUT_EVENT_BROWSER_COMPOSITE_COMPONENT,
+                               0,
+                               &composite_component)) {
+    base::TimeDelta delta =
+        gpu_swap_component.event_time - composite_component.event_time;
+    browser_composite_latency_history_.InsertSample(delta);
+  }
 }
 
 void RenderWidgetHostImpl::DidReceiveRendererFrame() {
   view_->DidReceiveRendererFrame();
 }
 
 void RenderWidgetHostImpl::WindowSnapshotAsyncCallback(
     int routing_id,
     int snapshot_id,
     gfx::Size snapshot_size,
@@ skipping 126 matching lines @@
     RenderWidgetHostImpl::GetRootBrowserAccessibilityManager() {
   return delegate_ ? delegate_->GetRootBrowserAccessibilityManager() : NULL;
 }
 
 BrowserAccessibilityManager*
     RenderWidgetHostImpl::GetOrCreateRootBrowserAccessibilityManager() {
   return delegate_ ?
       delegate_->GetOrCreateRootBrowserAccessibilityManager() : NULL;
 }
 
+base::TimeDelta RenderWidgetHostImpl::GetEstimatedBrowserCompositeTime() {
+  // TODO(brianderson): Remove lower bound on estimate once we're sure it won't
+  // cause regressions.
+  return std::max(
+      browser_composite_latency_history_.Percentile(
+          kBrowserCompositeLatencyEstimationPercentile) *
+          kBrowserCompositeLatencyEstimationSlack,
+      base::TimeDelta::FromMicroseconds(
+          (1.0f * base::Time::kMicrosecondsPerSecond) / (3.0f * 60)));
+}
+
 #if defined(OS_WIN)
 gfx::NativeViewAccessible
     RenderWidgetHostImpl::GetParentNativeViewAccessible() {
   return delegate_ ? delegate_->GetParentNativeViewAccessible() : NULL;
 }
 #endif
 
 SkColorType RenderWidgetHostImpl::PreferredReadbackFormat() {
   if (view_)
     return view_->PreferredReadbackFormat();
   return kN32_SkColorType;
 }
 
 }  // namespace content