Make ReflectorImpl use mailboxes

content/browser/compositor/reflector_impl.h

 // 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.
 
 #ifndef CONTENT_BROWSER_COMPOSITOR_REFLECTOR_IMPL_H_
 #define CONTENT_BROWSER_COMPOSITOR_REFLECTOR_IMPL_H_
 
 #include "base/id_map.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "base/synchronization/lock.h"
 #include "content/browser/compositor/image_transport_factory.h"
+#include "gpu/command_buffer/common/mailbox_holder.h"
 #include "ui/compositor/reflector.h"
 #include "ui/gfx/size.h"
 
 namespace base { class MessageLoopProxy; }
 
 namespace gfx { class Rect; }
 
 namespace ui {
 class Compositor;
 class Layer;
 }
 
 namespace content {
 
+class OwnedMailbox;
 class BrowserCompositorOutputSurface;
 
 // A reflector implementation that copies the framebuffer content
 // to the texture, then draw it onto the mirroring compositor.
-class ReflectorImpl : public ImageTransportFactoryObserver,
-                      public base::SupportsWeakPtr<ReflectorImpl>,
+class ReflectorImpl : public base::SupportsWeakPtr<ReflectorImpl>,
                       public ui::Reflector {
  public:
   ReflectorImpl(
       ui::Compositor* mirrored_compositor,
       ui::Layer* mirroring_layer,
       IDMap<BrowserCompositorOutputSurface>* output_surface_map,
       int surface_id);
 
   ui::Compositor* mirrored_compositor() {
     return mirrored_compositor_;
   }
 
-  void InitOnImplThread();
+  void InitOnImplThread(const gpu::MailboxHolder& mailbox_holder);
   void Shutdown();
   void ShutdownOnImplThread();
 
   // Post a task to attach the reflector to the output surface onto ImplThread.
   void ReattachToOutputSurfaceFromMainThread(
       BrowserCompositorOutputSurface* surface);
 
   // ui::Reflector implementation.
   virtual void OnMirroringCompositorResized() OVERRIDE;
 
-  // ImageTransportFactoryObsever implementation.
-  virtual void OnLostResources() OVERRIDE;
-
-  // Called when the output surface's size has changed.
-  // This must be called on ImplThread.
-  void OnReshape(gfx::Size size);
-
   // Called in |BrowserCompositorOutputSurface::SwapBuffers| to copy
   // the full screen image to the |texture_id_|. This must be called
   // on ImplThread.
   void OnSwapBuffers();
 
   // Called in |BrowserCompositorOutputSurface::PostSubBuffer| copy
   // the sub image given by |rect| to the texture.This must be called
   // on ImplThread.
   void OnPostSubBuffer(gfx::Rect rect);
 
   // Create a shared texture that will be used to copy the content of
   // mirrored compositor to the mirroring compositor.  This should
   // be posted to the main thread when the output is attached in
   // impl thread.
   void CreateSharedTextureOnMainThread(gfx::Size size);
 
   // Called when the source surface is bound and available. This must
   // be called on ImplThread.
-  void OnSourceSurfaceReady(int surface_id);
+  void OnSourceSurfaceReady(BrowserCompositorOutputSurface* surface);
+
+  void DetachFromOutputSurface();
 
  private:
   virtual ~ReflectorImpl();
 
   void AttachToOutputSurfaceOnImplThread(
+      const gpu::MailboxHolder& mailbox_holder,
       BrowserCompositorOutputSurface* surface);
 
   void UpdateTextureSizeOnMainThread(gfx::Size size);
 
   // Request full redraw on mirroring compositor.
   void FullRedrawOnMainThread(gfx::Size size);
 
   void UpdateSubBufferOnMainThread(gfx::Size size, gfx::Rect rect);
 
   // Request full redraw on mirrored compositor so that
   // the full content will be copied to mirroring compositor.
   void FullRedrawContentOnMainThread();
 
   // This exists just to hold a reference to a ReflectorImpl in a post task,
   // so the ReflectorImpl gets deleted when the function returns.
   static void DeleteOnMainThread(scoped_refptr<ReflectorImpl> reflector) {}
 
-  // These variables are initialized on MainThread before
-  // the reflector is attached to the output surface. Once
-  // attached, they must be accessed only on ImplThraed unless
-  // the context is lost. When the context is lost, these
-  // will be re-ininitiailzed when the new output-surface
-  // is created on MainThread.
-  int texture_id_;
-  base::Lock texture_lock_;
+  // Must be accessed only on ImplThread.

[danakj, 2014/04/08 16:08:01]

This starts to remind me of cc::ThreadProxy. Consider putting these into a impl
and main structs, and DCHECKing the access to the struct via impl() and main()
accessors to them? Possibly as another CL?

[piman, 2014/04/08 23:17:46]

Done.

+  IDMap<BrowserCompositorOutputSurface>* output_surface_map_;
+  BrowserCompositorOutputSurface* output_surface_;
+  scoped_ptr<GLHelper> gl_helper_;
+  unsigned impl_thread_texture_id_;
+  gpu::MailboxHolder impl_thread_mailbox_holder_;
   gfx::Size texture_size_;
 
-  // Must be accessed only on ImplThread.
-  IDMap<BrowserCompositorOutputSurface>* output_surface_map_;
-  scoped_ptr<GLHelper> gl_helper_;
-
   // Must be accessed only on MainThread.
+  scoped_refptr<OwnedMailbox> main_thread_mailbox_;
+  bool needs_set_mailbox_;
   ui::Compositor* mirrored_compositor_;
-  ui::Compositor* mirroring_compositor_;
   ui::Layer* mirroring_layer_;
-  scoped_refptr<ui::Texture> shared_texture_;
   scoped_refptr<base::MessageLoopProxy> impl_message_loop_;
   scoped_refptr<base::MessageLoopProxy> main_message_loop_;

[danakj, 2014/04/08 16:08:01]

Can this only be accessed on MainThread also? Maybe the grouping here is a bit
off, or an extra comment is needed?

[piman, 2014/04/08 23:17:46]

Done.

   int surface_id_;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_COMPOSITOR_REFLECTOR_IMPL_H_