content: Partial copy workaround for devices with known upload performance problems.

content/renderer/gpu/render_widget_compositor.cc

 // Copyright (c) 2013 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/renderer/gpu/render_widget_compositor.h"
 
 #include <limits>
 #include <string>
 
 #include "base/command_line.h"
@@ skipping 32 matching lines @@
 #include "third_party/WebKit/public/platform/WebLayoutAndPaintAsyncCallback.h"
 #include "third_party/WebKit/public/platform/WebSize.h"
 #include "third_party/WebKit/public/web/WebKit.h"
 #include "third_party/WebKit/public/web/WebRuntimeFeatures.h"
 #include "third_party/WebKit/public/web/WebSelection.h"
 #include "third_party/WebKit/public/web/WebWidget.h"
 #include "ui/gl/gl_switches.h"
 #include "ui/native_theme/native_theme_switches.h"
 
 #if defined(OS_ANDROID)
+#include "base/android/build_info.h"
 #include "content/renderer/android/synchronous_compositor_factory.h"
 #include "ui/gfx/android/device_display_info.h"
 #endif
 
 namespace base {
 class Value;
 }
 
 namespace cc {
 class Layer;
@@ skipping 108 matching lines @@
   }
 #elif defined(OS_CHROMEOS)
   // Use 512 for high DPI (dsf=2.0f) devices.
   if (widget->screen_info().deviceScaleFactor >= 2.0f)
     default_tile_size = 512;
 #endif
 
   return gfx::Size(default_tile_size, default_tile_size);
 }
 
-int GetMaxBytesPerCopyOperation() {
-  const int kMegabyte = 1024 * 1024;
-
-  // 4MiB is the size of 4 512x512 tiles, which has proven to be a good
-  // default batch size for copy operations.
-  return kMegabyte * 4;
-}
-
 // Check cc::TopControlsState, and blink::WebTopControlsState
 // are kept in sync.
 static_assert(int(blink::WebTopControlsBoth) == int(cc::BOTH),
               "mismatching enums: BOTH");
 static_assert(int(blink::WebTopControlsHidden) == int(cc::HIDDEN),
               "mismatching enums: HIDDEN");
 static_assert(int(blink::WebTopControlsShown) == int(cc::SHOWN),
               "mismatching enums: SHOWN");
 
 static cc::TopControlsState ConvertTopControlsState(
@@ skipping 261 matching lines @@
     settings.create_low_res_tiling = false;
   if (cmd->HasSwitch(cc::switches::kEnableBeginFrameScheduling))
     settings.use_external_begin_frame_source = true;
 
   if (widget_->for_oopif()) {
     // TODO(simonhong): Apply BeginFrame scheduling for OOPIF.
     // See crbug.com/471411.
     settings.use_external_begin_frame_source = false;
   }
 
-  settings.max_bytes_per_copy_operation = GetMaxBytesPerCopyOperation();
-
   scoped_refptr<base::SingleThreadTaskRunner> compositor_thread_task_runner =
       compositor_deps_->GetCompositorImplThreadTaskRunner();
   scoped_refptr<base::SingleThreadTaskRunner>
       main_thread_compositor_task_runner =
           compositor_deps_->GetCompositorMainThreadTaskRunner();
   cc::SharedBitmapManager* shared_bitmap_manager =
       compositor_deps_->GetSharedBitmapManager();
   gpu::GpuMemoryBufferManager* gpu_memory_buffer_manager =
       compositor_deps_->GetGpuMemoryBufferManager();
   cc::TaskGraphRunner* task_graph_runner =
@@ skipping 528 matching lines @@
     return;
   provider->ContextGL()->RateLimitOffscreenContextCHROMIUM();
 }
 
 void RenderWidgetCompositor::SetSurfaceIdNamespace(
     uint32_t surface_id_namespace) {
   layer_tree_host_->set_surface_id_namespace(surface_id_namespace);
 }
 
 }  // namespace content