Remove gpu side LatencyInfo merging

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 1448 matching lines @@
 void RenderWidgetHostImpl::OnPaintAtSizeAck(int tag, const gfx::Size& size) {
   std::pair<int, gfx::Size> details = std::make_pair(tag, size);
   NotificationService::current()->Notify(
       NOTIFICATION_RENDER_WIDGET_HOST_DID_RECEIVE_PAINT_AT_SIZE_ACK,
       Source<RenderWidgetHost>(this),
       Details<std::pair<int, gfx::Size> >(&details));
 }
 
 #if defined(OS_MACOSX)
 void RenderWidgetHostImpl::OnCompositorSurfaceBuffersSwapped(
       const ViewHostMsg_CompositorSurfaceBuffersSwapped_Params& params) {

[jln (very slow on Chromium), 2014/01/09 23:13:27]

Could you add a check of latency_info.size() for something "reasonable"?

We're trying to remove / prevent cases where renderers can populate large
structures into the memory of the browser.

You also would need to add such a check in render_process_host_impl.cc.

[Yufeng Shen (Slow to review), 2014/01/10 01:14:01]

I noticed that ViewHostMsg_CompositorSurfaceBuffersSwapped is generated in
GpuProcessHost::OnAcceleratedSurfaceBuffersSwapped().

So I put a guard there if the latency_info.size() is too big, then
end the LatencyInfo there (adding special component to the LatencyInfo so it
will be captured during telemetry test) and clear the latency_info list. So no
big msg will be sent to browser.

   TRACE_EVENT0("renderer_host",
                "RenderWidgetHostImpl::OnCompositorSurfaceBuffersSwapped");
   if (!view_) {
     AcceleratedSurfaceMsg_BufferPresented_Params ack_params;
     ack_params.sync_point = 0;
     RenderWidgetHostImpl::AcknowledgeBufferPresent(params.route_id,
                                                    params.gpu_process_host_id,
                                                    ack_params);
     return;
   }
@@ skipping 963 matching lines @@
       return;
     }
   }
 
   Send(new ViewMsg_WindowSnapshotCompleted(
       GetRoutingID(), snapshot_id, gfx::Size(), png));
 }
 
 // static
 void RenderWidgetHostImpl::CompositorFrameDrawn(
-    const ui::LatencyInfo& latency_info) {
-  std::set<RenderWidgetHostImpl*> rwhi_set;
-
-  for (ui::LatencyInfo::LatencyMap::const_iterator b =
-           latency_info.latency_components.begin();
-       b != latency_info.latency_components.end();
-       ++b) {
-    if (b->first.first == ui::INPUT_EVENT_LATENCY_BEGIN_RWH_COMPONENT ||
-        b->first.first == ui::WINDOW_SNAPSHOT_FRAME_NUMBER_COMPONENT) {
-      // Matches with GetLatencyComponentId
-      int routing_id = b->first.second & 0xffffffff;
-      int process_id = (b->first.second >> 32) & 0xffffffff;
-      RenderWidgetHost* rwh =
-          RenderWidgetHost::FromID(process_id, routing_id);
-      if (!rwh) {
-        continue;
+    const std::vector<ui::LatencyInfo>& latency_info) {
+  for (size_t i = 0; i < latency_info.size(); i++) {
+    std::set<RenderWidgetHostImpl*> rwhi_set;
+    for (ui::LatencyInfo::LatencyMap::const_iterator b =
+             latency_info[i].latency_components.begin();
+         b != latency_info[i].latency_components.end();
+         ++b) {
+      if (b->first.first == ui::INPUT_EVENT_LATENCY_BEGIN_RWH_COMPONENT ||
+          b->first.first == ui::WINDOW_SNAPSHOT_FRAME_NUMBER_COMPONENT) {
+        // Matches with GetLatencyComponentId
+        int routing_id = b->first.second & 0xffffffff;
+        int process_id = (b->first.second >> 32) & 0xffffffff;
+        RenderWidgetHost* rwh =
+            RenderWidgetHost::FromID(process_id, routing_id);
+        if (!rwh) {
+          continue;
+        }
+        RenderWidgetHostImpl* rwhi = RenderWidgetHostImpl::From(rwh);
+        if (rwhi_set.insert(rwhi).second)
+          rwhi->FrameSwapped(latency_info[i]);
       }
-      RenderWidgetHostImpl* rwhi = RenderWidgetHostImpl::From(rwh);
-      if (rwhi_set.insert(rwhi).second)
-        rwhi->FrameSwapped(latency_info);
     }
   }
 }
 
 }  // namespace content