Make GPU back-pressure work with remote CALayers

content/browser/compositor/browser_compositor_view_mac.mm

 // 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.
 
 #include "content/browser/compositor/browser_compositor_view_mac.h"
 
 #include "base/debug/trace_event.h"
 #include "base/lazy_instance.h"
+#include "content/browser/gpu/gpu_process_host_ui_shim.h"
 #include "content/browser/compositor/browser_compositor_view_private_mac.h"
+#include "content/common/gpu/gpu_messages.h"
 
 ////////////////////////////////////////////////////////////////////////////////
 // BrowserCompositorViewMac
 
 namespace content {
 namespace {
 
 // The number of placeholder objects allocated. If this reaches zero, then
 // the BrowserCompositorViewMacInternal being held on to for recycling,
 // |g_recyclable_internal_view|, will be freed.
@@ skipping 49 matching lines @@
 void BrowserCompositorViewMac::EndPumpingFrames() {
   if (internal_view_)
     internal_view_->EndPumpingFrames();
 }
 
 // static
 void BrowserCompositorViewMac::GotAcceleratedFrame(
     gfx::AcceleratedWidget widget,
     uint64 surface_handle, int surface_id,
     const std::vector<ui::LatencyInfo>& latency_info,
-    gfx::Size pixel_size, float scale_factor) {
+    gfx::Size pixel_size, float scale_factor,
+    int gpu_host_id, int gpu_route_id) {
   BrowserCompositorViewMacInternal* internal_view =
       BrowserCompositorViewMacInternal::FromAcceleratedWidget(widget);
+  int renderer_id = 0;
   if (internal_view) {
     internal_view->GotAcceleratedFrame(
         surface_handle, surface_id, latency_info, pixel_size, scale_factor);
+    renderer_id = internal_view->GetRendererID();
+  }
+
+  // Acknowledge the swap, now that it has been processed.
+  AcceleratedSurfaceMsg_BufferPresented_Params ack_params;
+  ack_params.sync_point = 0;
+  ack_params.renderer_id = renderer_id;
+  GpuProcessHostUIShim* ui_shim = GpuProcessHostUIShim::FromID(gpu_host_id);
+  if (ui_shim) {
+    ui_shim->Send(new AcceleratedSurfaceMsg_BufferPresented(
+        gpu_route_id, ack_params));
   }
 }
 
 // static
 void BrowserCompositorViewMac::GotSoftwareFrame(
     gfx::AcceleratedWidget widget,
     cc::SoftwareFrameData* frame_data, float scale_factor, SkCanvas* canvas) {
   BrowserCompositorViewMacInternal* internal_view =
       BrowserCompositorViewMacInternal::FromAcceleratedWidget(widget);
   if (internal_view)
@@ skipping 11 matching lines @@
   DCHECK_GT(g_placeholder_count, 0u);
   g_placeholder_count -= 1;
 
   // If there are no placeholders allocated, destroy the recyclable
   // BrowserCompositorViewMacInternal.
   if (!g_placeholder_count)
     g_recyclable_internal_view.Get().reset();
 }
 
 }  // namespace content