cc: Add initial GPU-to-GPU copy rasterizer implementation.

cc/trees/layer_tree_host_impl.cc

Index: cc/trees/layer_tree_host_impl.cc
diff --git a/cc/trees/layer_tree_host_impl.cc b/cc/trees/layer_tree_host_impl.cc
index 9fac00412bd0ef3329952610fa3236e14b7e03a7..79fb41a8ae4797eeeb0dd5dc9f75f124eb209060 100644
--- a/cc/trees/layer_tree_host_impl.cc
+++ b/cc/trees/layer_tree_host_impl.cc
@@ -44,6 +44,7 @@
 #include "cc/quads/solid_color_draw_quad.h"
 #include "cc/quads/texture_draw_quad.h"
 #include "cc/resources/direct_raster_worker_pool.h"
+#include "cc/resources/image_copy_raster_worker_pool.h"
 #include "cc/resources/image_raster_worker_pool.h"
 #include "cc/resources/memory_history.h"
 #include "cc/resources/picture_layer_tiling.h"
@@ -69,6 +70,10 @@
 
 namespace {
 
+const int kStagingPoolMemoryLimitWhenVisible = 32 * 1024 * 1024;

[vmpstr, 2014/04/23 17:25:46]

Can you put a TODO here to maybe move this into global_state or something like
that? Similar to our other memory limits. My concern is that this will be hard
to tune per platform.

[reveman, 2014/04/24 19:20:43]

Latest patch uses GetMaxTransferBufferUsageBytes instead, which is our current
way of tuning the amount of memory used for pending uploads. That limit might
not be perfect in this case but I think it's what we should be using long term.

+const int kStagingPoolUnusedMemoryLimit = kStagingPoolMemoryLimitWhenVisible;
+const int kStagingPoolResourceCountLimit = 48;
+
 void DidVisibilityChange(cc::LayerTreeHostImpl* id, bool visible) {
   if (visible) {
     TRACE_EVENT_ASYNC_BEGIN1("webkit",
@@ -122,6 +127,16 @@ unsigned GetMapImageTextureTarget(cc::ContextProvider* context_provider) {
   return GL_TEXTURE_2D;
 }
 
+unsigned GetCopyImageTextureTarget(cc::ContextProvider* context_provider) {
+  if (!context_provider)
+    return GL_TEXTURE_2D;
+
+  if (context_provider->ContextCapabilities().gpu.egl_image_external)
+    return GL_TEXTURE_EXTERNAL_OES;
+
+  return GL_TEXTURE_2D;
+}
+
 }  // namespace
 
 namespace cc {
@@ -310,6 +325,7 @@ LayerTreeHostImpl::~LayerTreeHostImpl() {
   resource_pool_.reset();
   raster_worker_pool_.reset();
   direct_raster_worker_pool_.reset();
+  staging_resource_pool_.reset();
 }
 
 void LayerTreeHostImpl::BeginMainFrameAborted(bool did_handle) {
@@ -1200,6 +1216,15 @@ void LayerTreeHostImpl::UpdateTileManagerMemoryPolicy(
       global_tile_state_.unused_memory_limit_in_bytes,
       global_tile_state_.num_resources_limit);
 
+  // We currently use hard-coded limits for staging pool limits.
+  if (staging_resource_pool_) {
+    staging_resource_pool_->CheckBusyResources();
+    staging_resource_pool_->SetResourceUsageLimits(
+        visible_ ? kStagingPoolMemoryLimitWhenVisible : 0,
+        kStagingPoolUnusedMemoryLimit,
+        kStagingPoolResourceCountLimit);
+  }
+
   DidModifyTilePriorities();
 }
 
@@ -1806,20 +1831,43 @@ void LayerTreeHostImpl::CreateAndSetTileManager(
     ResourceProvider* resource_provider,
     ContextProvider* context_provider,
     bool using_map_image,
+    bool use_zero_copy,
     bool allow_rasterize_on_demand) {
   DCHECK(settings_.impl_side_painting);
   DCHECK(resource_provider);
   DCHECK(proxy_->ImplThreadTaskRunner());
 
   if (using_map_image) {
-    raster_worker_pool_ =
-        ImageRasterWorkerPool::Create(proxy_->ImplThreadTaskRunner(),
-                                      RasterWorkerPool::GetTaskGraphRunner(),
-                                      resource_provider);
-    resource_pool_ =
-        ResourcePool::Create(resource_provider,
-                             GetMapImageTextureTarget(context_provider),
-                             resource_provider->best_texture_format());
+    // We need to create a staging resource pool unless we're using
+    // ImageRasterWorkerPool that implements zero-copy.
+    if (use_zero_copy || !resource_provider_->use_sync_query()) {
+      resource_pool_ =
+          ResourcePool::Create(resource_provider,
+                               GetMapImageTextureTarget(context_provider),
+                               resource_provider->best_texture_format());
+      raster_worker_pool_ =
+          ImageRasterWorkerPool::Create(proxy_->ImplThreadTaskRunner(),
+                                        RasterWorkerPool::GetTaskGraphRunner(),
+                                        resource_provider);
+    } else {
+      // TODO(reveman): Use GetMapImageTextureTarget instead of
+      // GetCopyImageTextureTarget when GL_TEXTURE_RECTANGLE_ARB support has
+      // been added to CHROMIUM_copy_texture.
+      staging_resource_pool_ =
+          ResourcePool::Create(resource_provider,
+                               GetCopyImageTextureTarget(context_provider),
+                               resource_provider->best_texture_format());
+      resource_pool_ =
+          ResourcePool::Create(resource_provider,
+                               GL_TEXTURE_2D,
+                               resource_provider->best_texture_format());
+
+      raster_worker_pool_ = ImageCopyRasterWorkerPool::Create(
+          proxy_->ImplThreadTaskRunner(),
+          RasterWorkerPool::GetTaskGraphRunner(),
+          resource_provider,
+          staging_resource_pool_.get());
+    }
   } else {
     raster_worker_pool_ = PixelBufferRasterWorkerPool::Create(
         proxy_->ImplThreadTaskRunner(),
@@ -1865,6 +1913,7 @@ bool LayerTreeHostImpl::InitializeRenderer(
   renderer_.reset();
   tile_manager_.reset();
   resource_pool_.reset();
+  staging_resource_pool_.reset();
   raster_worker_pool_.reset();
   direct_raster_worker_pool_.reset();
   resource_provider_.reset();
@@ -1897,6 +1946,7 @@ bool LayerTreeHostImpl::InitializeRenderer(
         resource_provider.get(),
         output_surface->context_provider().get(),
         GetRendererCapabilities().using_map_image,
+        settings_.use_zero_copy,
         GetRendererCapabilities().allow_rasterize_on_demand);
   }
 
@@ -1997,6 +2047,7 @@ void LayerTreeHostImpl::ReleaseGL() {
   resource_pool_.reset();
   raster_worker_pool_.reset();
   direct_raster_worker_pool_.reset();
+  staging_resource_pool_.reset();
   resource_provider_->InitializeSoftware();
 
   bool skip_gl_renderer = true;
@@ -2008,6 +2059,7 @@ void LayerTreeHostImpl::ReleaseGL() {
   CreateAndSetTileManager(resource_provider_.get(),
                           NULL,
                           GetRendererCapabilities().using_map_image,
+                          settings_.use_zero_copy,
                           GetRendererCapabilities().allow_rasterize_on_demand);
   DCHECK(tile_manager_);