Use LatencyInfoSwapPromise to track LatencyInfo through compositor

cc/trees/layer_tree_impl.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/trees/layer_tree_impl.h"
 
 #include "base/debug/trace_event.h"
 #include "cc/animation/keyframed_animation_curve.h"
 #include "cc/animation/scrollbar_animation_controller.h"
 #include "cc/base/math_util.h"
@@ skipping 102 matching lines @@
 
 void LayerTreeImpl::PushPropertiesTo(LayerTreeImpl* target_tree) {
   // The request queue should have been processed and does not require a push.
   DCHECK_EQ(ui_resource_request_queue_.size(), 0u);
 
   if (next_activation_forces_redraw_) {
     layer_tree_host_impl_->SetFullRootLayerDamage();
     next_activation_forces_redraw_ = false;
   }
 
-  target_tree->SetLatencyInfo(latency_info_);
-  latency_info_.Clear();
-
   target_tree->PassSwapPromises(&swap_promise_list_);
 
   target_tree->SetPageScaleFactorAndLimits(
       page_scale_factor(), min_page_scale_factor(), max_page_scale_factor());
   target_tree->SetPageScaleDelta(
       target_tree->page_scale_delta() / target_tree->sent_page_scale_delta());
   target_tree->set_sent_page_scale_delta(1);
 
   if (settings().use_pinch_virtual_viewport) {
     target_tree->SetViewportLayersFromIds(
@@ skipping 321 matching lines @@
 
 void LayerTreeImpl::UnregisterLayer(LayerImpl* layer) {
   DCHECK(LayerById(layer->id()));
   layer_id_map_.erase(layer->id());
 }
 
 void LayerTreeImpl::PushPersistedState(LayerTreeImpl* pending_tree) {
   pending_tree->SetCurrentlyScrollingLayer(
       LayerTreeHostCommon::FindLayerInSubtree(pending_tree->root_layer(),
           currently_scrolling_layer_ ? currently_scrolling_layer_->id() : 0));
-  pending_tree->SetLatencyInfo(latency_info_);
-  latency_info_.Clear();
 }
 
 static void DidBecomeActiveRecursive(LayerImpl* layer) {
   layer->DidBecomeActive();
   for (size_t i = 0; i < layer->children().size(); ++i)
     DidBecomeActiveRecursive(layer->children()[i]);
 }
 
 void LayerTreeImpl::DidBecomeActive() {
   if (!root_layer())
@@ skipping 213 matching lines @@
 
   gfx::Vector2dF original_viewport_size =
       gfx::RectF(root_container->bounds()).bottom_right() -
       gfx::PointF();
   original_viewport_size.Scale(1 / page_scale_factor());
 
   root_scroll->SetFixedContainerSizeDelta(
       scrollable_viewport_size - original_viewport_size);
 }
 
-void LayerTreeImpl::SetLatencyInfo(const ui::LatencyInfo& latency_info) {
-  latency_info_.MergeWith(latency_info);
-}
-
-const ui::LatencyInfo& LayerTreeImpl::GetLatencyInfo() {
-  return latency_info_;
-}
-
-void LayerTreeImpl::ClearLatencyInfo() {
-  latency_info_.Clear();
+// TODO(miletus): The merge here is a temporary hack. Should change the
+// function to be
+// TakeLatencyInfo(std::vector<ui::LatencyInfo>* latency_info)
+// Once we remove the LatencyInfo merge in the gpu side.
+void LayerTreeImpl::TakeLatencyInfo(ui::LatencyInfo* latency_info) {

[danakj, 2013/11/26 19:17:53]

Why isn't this going through the DidSwap() method? We shouldn't be using the
CompositorFrame for plumbing this info at all anymore should we?

[Yufeng Shen (Slow to review), 2013/11/27 20:05:33]

Removed.

Changed the DidSwap() signature to be
virtual void DidSwap(CompositorFrameMetadata* metadata)

so that LatencyInfoSwapPromise::DidSwap(CompositorFrameMetadata* metadata)
will merge its latencyinfo into metadata.

+  ScopedPtrVector<SwapPromise>::iterator it = swap_promise_list_.begin();
+  for (; it != swap_promise_list_.end(); it++) {
+    if ((*it) && ((*it)->type() == SwapPromise::SWAP_PROMISE_LATENCY_INFO)) {
+      latency_info->MergeWith(
+          (static_cast<LatencyInfoSwapPromise*>(*it))->GetLatencyInfo());
+    }
+  }
 }
 
 void LayerTreeImpl::QueueSwapPromise(scoped_ptr<SwapPromise> swap_promise) {
   if (swap_promise_list_.size() > kMaxQueuedSwapPromiseNumber)
     BreakSwapPromises(SwapPromise::SWAP_PROMISE_LIST_OVERFLOW);
   swap_promise_list_.push_back(swap_promise.Pass());
 }
 
 void LayerTreeImpl::PassSwapPromises(
     ScopedPtrVector<SwapPromise>* new_swap_promise) {
@@ skipping 87 matching lines @@
 const std::vector<LayerImpl*> LayerTreeImpl::LayersWithCopyOutputRequest()
     const {
   // Only the active tree needs to know about layers with copy requests, as
   // they are aborted if not serviced during draw.
   DCHECK(IsActiveTree());
 
   return layers_with_copy_output_request_;
 }
 
 }  // namespace cc