cc: Add mailbox support to ResourceProvider write locks.

cc/raster/gpu_raster_buffer_provider.cc

Index: cc/raster/gpu_raster_buffer_provider.cc
diff --git a/cc/raster/gpu_raster_buffer_provider.cc b/cc/raster/gpu_raster_buffer_provider.cc
index 51d8898283651d8113effad512a9f4766316691f..fd3026821b99061e9080fb0a8ae0e7c66b68e581 100644
--- a/cc/raster/gpu_raster_buffer_provider.cc
+++ b/cc/raster/gpu_raster_buffer_provider.cc
@@ -26,15 +26,12 @@ namespace {
 
 class RasterBufferImpl : public RasterBuffer {
  public:
-  RasterBufferImpl(GpuRasterizer* rasterizer,
-                   const Resource* resource,
-                   uint64_t resource_content_id,
-                   uint64_t previous_content_id)
-      : rasterizer_(rasterizer),
-        lock_(rasterizer->resource_provider(), resource->id()),
-        resource_has_previous_content_(
-            resource_content_id && resource_content_id == previous_content_id) {
-  }
+  RasterBufferImpl(GpuRasterBufferProvider* client,
+                   std::unique_ptr<ResourceProvider::ScopedWriteLockGr> lock,
+                   bool resource_has_previous_content)
+      : client_(client),
+        lock_(std::move(lock)),
+        resource_has_previous_content_(resource_has_previous_content) {}
 
   // Overridden from RasterBuffer:
   void Playback(
@@ -45,42 +42,15 @@ class RasterBufferImpl : public RasterBuffer {
       float scale,
       const RasterSource::PlaybackSettings& playback_settings) override {
     TRACE_EVENT0("cc", "RasterBufferImpl::Playback");
-    // GPU raster doesn't do low res tiles, so should always include images.
-    DCHECK(!playback_settings.skip_images);
-    ContextProvider* context_provider = rasterizer_->resource_provider()
-                                            ->output_surface()
-                                            ->worker_context_provider();
-    DCHECK(context_provider);
-
-    ContextProvider::ScopedContextLock scoped_context(context_provider);
-
-    gfx::Rect playback_rect = raster_full_rect;
-    if (resource_has_previous_content_) {
-      playback_rect.Intersect(raster_dirty_rect);
-    }
-    DCHECK(!playback_rect.IsEmpty())
-        << "Why are we rastering a tile that's not dirty?";
-
-    // TODO(danakj): Implement partial raster with raster_dirty_rect.
-    // Rasterize source into resource.
-    rasterizer_->RasterizeSource(&lock_, raster_source, raster_full_rect,
-                                 playback_rect, scale, playback_settings);
-
-    gpu::gles2::GLES2Interface* gl = scoped_context.ContextGL();
-    const uint64_t fence_sync = gl->InsertFenceSyncCHROMIUM();
-
-    // Barrier to sync worker context output to cc context.
-    gl->OrderingBarrierCHROMIUM();
-
-    // Generate sync token after the barrier for cross context synchronization.
-    gpu::SyncToken sync_token;
-    gl->GenUnverifiedSyncTokenCHROMIUM(fence_sync, sync_token.GetData());
-    lock_.UpdateResourceSyncToken(sync_token);
+    client_->PlaybackOnWorkerThread(lock_.get(), resource_has_previous_content_,
+                                    raster_source, raster_full_rect,
+                                    raster_dirty_rect, new_content_id, scale,
+                                    playback_settings);
   }
 
  private:
-  GpuRasterizer* rasterizer_;
-  ResourceProvider::ScopedWriteLockGr lock_;
+  GpuRasterBufferProvider* client_;
+  std::unique_ptr<ResourceProvider::ScopedWriteLockGr> lock_;
   bool resource_has_previous_content_;
 
   DISALLOW_COPY_AND_ASSIGN(RasterBufferImpl);
@@ -93,21 +63,24 @@ std::unique_ptr<RasterBufferProvider> GpuRasterBufferProvider::Create(
     ContextProvider* context_provider,
     ResourceProvider* resource_provider,
     bool use_distance_field_text,
-    int gpu_rasterization_msaa_sample_count) {
+    int gpu_rasterization_msaa_sample_count,
+    bool async_worker_context_enabled) {
   return base::WrapUnique<RasterBufferProvider>(new GpuRasterBufferProvider(
       context_provider, resource_provider, use_distance_field_text,
-      gpu_rasterization_msaa_sample_count));
+      gpu_rasterization_msaa_sample_count, async_worker_context_enabled));
 }
 
 GpuRasterBufferProvider::GpuRasterBufferProvider(
     ContextProvider* context_provider,
     ResourceProvider* resource_provider,
     bool use_distance_field_text,
-    int gpu_rasterization_msaa_sample_count)
+    int gpu_rasterization_msaa_sample_count,
+    bool async_worker_context_enabled)
     : rasterizer_(new GpuRasterizer(context_provider,
                                     resource_provider,
                                     use_distance_field_text,
-                                    gpu_rasterization_msaa_sample_count)) {}
+                                    gpu_rasterization_msaa_sample_count)),
+      async_worker_context_enabled_(async_worker_context_enabled) {}
 
 GpuRasterBufferProvider::~GpuRasterBufferProvider() {}
 
@@ -115,8 +88,13 @@ std::unique_ptr<RasterBuffer> GpuRasterBufferProvider::AcquireBufferForRaster(
     const Resource* resource,
     uint64_t resource_content_id,
     uint64_t previous_content_id) {
+  bool resource_has_previous_content =
+      resource_content_id && resource_content_id == previous_content_id;
   return std::unique_ptr<RasterBuffer>(new RasterBufferImpl(
-      rasterizer_.get(), resource, resource_content_id, previous_content_id));
+      this, base::WrapUnique(new ResourceProvider::ScopedWriteLockGr(
+                rasterizer_->resource_provider(), resource->id(),
+                async_worker_context_enabled_)),
+      resource_has_previous_content));
 }
 
 void GpuRasterBufferProvider::ReleaseBufferForRaster(
@@ -127,11 +105,15 @@ void GpuRasterBufferProvider::ReleaseBufferForRaster(
 void GpuRasterBufferProvider::OrderingBarrier() {
   TRACE_EVENT0("cc", "GpuRasterBufferProvider::OrderingBarrier");
 
-  rasterizer_->resource_provider()
-      ->output_surface()
-      ->context_provider()
-      ->ContextGL()
-      ->OrderingBarrierCHROMIUM();
+  gpu::gles2::GLES2Interface* gl = rasterizer_->resource_provider()
+                                       ->output_surface()
+                                       ->context_provider()
+                                       ->ContextGL();
+
+  // Synchronize with compositor.
+  GLuint64 fence = gl->InsertFenceSyncCHROMIUM();
+  gl->OrderingBarrierCHROMIUM();
+  gl->GenUnverifiedSyncTokenCHROMIUM(fence, sync_token_.GetData());
 }
 
 ResourceFormat GpuRasterBufferProvider::GetResourceFormat(
@@ -147,4 +129,50 @@ bool GpuRasterBufferProvider::GetResourceRequiresSwizzle(
 
 void GpuRasterBufferProvider::Shutdown() {}
 
+void GpuRasterBufferProvider::PlaybackOnWorkerThread(
+    ResourceProvider::ScopedWriteLockGr* lock,
+    bool resource_has_previous_content,
+    const RasterSource* raster_source,
+    const gfx::Rect& raster_full_rect,
+    const gfx::Rect& raster_dirty_rect,
+    uint64_t new_content_id,
+    float scale,
+    const RasterSource::PlaybackSettings& playback_settings) {
+  // GPU raster doesn't do low res tiles, so should always include images.
+  DCHECK(!playback_settings.skip_images);
+  ContextProvider* context_provider = rasterizer_->resource_provider()
+                                          ->output_surface()
+                                          ->worker_context_provider();
+  DCHECK(context_provider);
+
+  ContextProvider::ScopedContextLock scoped_context(context_provider);
+  gpu::gles2::GLES2Interface* gl = scoped_context.ContextGL();
+
+  gfx::Rect playback_rect = raster_full_rect;
+  if (resource_has_previous_content) {
+    playback_rect.Intersect(raster_dirty_rect);
+  }
+  DCHECK(!playback_rect.IsEmpty())
+      << "Why are we rastering a tile that's not dirty?";
+
+  // Synchronize with compositor if worker context is async.
+  DCHECK(sync_token_.HasData());
+  gl->WaitSyncTokenCHROMIUM(sync_token_.GetData());
+
+  // TODO(danakj): Implement partial raster with raster_dirty_rect.
+  // Rasterize source into resource.
+  rasterizer_->RasterizeSource(lock, raster_source, raster_full_rect,
+                               playback_rect, scale, playback_settings);
+
+  const uint64_t fence_sync = gl->InsertFenceSyncCHROMIUM();
+
+  // Barrier to sync worker context output to cc context.
+  gl->OrderingBarrierCHROMIUM();
+
+  // Generate sync token after the barrier for cross context synchronization.
+  gpu::SyncToken sync_token;
+  gl->GenUnverifiedSyncTokenCHROMIUM(fence_sync, sync_token.GetData());
+  lock->UpdateResourceSyncToken(sync_token);
+}
+
 }  // namespace cc