gpu: Mailbox emulation with EGLImage

gpu/command_buffer/service/texture_definition.h

+// Copyright (c) 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 GPU_COMMAND_BUFFER_SERVICE_TEXTURE_DEFINITION_H_
+#define GPU_COMMAND_BUFFER_SERVICE_TEXTURE_DEFINITION_H_
+
+#include <list>
+#include <vector>
+
+#include "base/callback.h"
+#include "base/memory/linked_ptr.h"
+#include "base/memory/ref_counted.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/synchronization/lock.h"
+#include "gpu/command_buffer/service/gl_utils.h"
+#include "ui/gl/gl_fence.h"
+
+namespace gfx {
+class GLFence;
+class GLImage;
+}
+
+namespace gpu {
+namespace gles2 {
+
+class Texture;
+
+class NativeImageBuffer : public base::RefCountedThreadSafe<NativeImageBuffer> {
+ public:
+  static NativeImageBuffer* Create(GLuint texture_id);
+  virtual void BindToTexture(GLenum target) = 0;
+
+  void AddClient(gfx::GLImage* client);
+  void RemoveClient(gfx::GLImage* client);
+  bool IsClient(gfx::GLImage* client);
+
+  void WillRead(gfx::GLImage* client);
+  void WillWrite(gfx::GLImage* client);
+  void DidRead(gfx::GLImage* client);
+  void DidWrite(gfx::GLImage* client);
+
+ protected:
+  friend class base::RefCountedThreadSafe<NativeImageBuffer>;
+  NativeImageBuffer();
+  virtual ~NativeImageBuffer();
+
+  base::Lock lock_;
+
+  struct ClientInfo {
+    ClientInfo(gfx::GLImage* client);
+    ~ClientInfo();
+
+    gfx::GLImage* client;
+    bool needs_wait_before_read;
+    linked_ptr<gfx::GLFence> read_fence;
+  };
+  std::list<ClientInfo> client_infos_;
+  scoped_ptr<gfx::GLFence> write_fence_;
+  gfx::GLImage* write_client_;
+
+  DISALLOW_COPY_AND_ASSIGN(NativeImageBuffer);
+};
+
+// An immutable description that can be used to create a texture that shares
+// the underlying image buffer(s).
+class TextureDefinition {
+ public:
+  TextureDefinition(GLenum target,
+                    Texture* texture,
+                    unsigned int version,
+                    NativeImageBuffer* image);
+  virtual ~TextureDefinition();
+
+  Texture* CreateTexture() const;
+  void UpdateTexture(Texture* texture) const;
+
+  unsigned int version() const { return version_; }
+  bool IsNewerThan(unsigned int version) const {
+    return (int)(version_ - version) > 0;

[piman, 2014/03/13 04:41:58]

int overflow = undefined. I'm afraid the compiler can legally treat this as
version_ != version.
How about version_ - version < 0x80000000 ?

[no sievers, 2014/03/13 20:50:15]

Done. Inverted, since you pointed out that 'equal' can skip (not for Pull
though).

[piman, 2014/03/13 23:29:06]

Why can't we skip for Pull?

+  }
+  bool Matches(const Texture* texture) const;
+
+  scoped_refptr<NativeImageBuffer> image() { return image_; }
+
+ private:
+  struct LevelInfo {
+    LevelInfo(GLenum target,
+              GLenum internal_format,
+              GLsizei width,
+              GLsizei height,
+              GLsizei depth,
+              GLint border,
+              GLenum format,
+              GLenum type,
+              bool cleared);
+    ~LevelInfo();
+
+    GLenum target;
+    GLenum internal_format;
+    GLsizei width;
+    GLsizei height;
+    GLsizei depth;
+    GLint border;
+    GLenum format;
+    GLenum type;
+    bool cleared;
+  };
+
+  typedef std::vector<std::vector<LevelInfo> > LevelInfos;
+
+  unsigned int version_;
+  GLenum target_;
+  scoped_refptr<NativeImageBuffer> image_;

[piman, 2014/03/13 04:41:58]

nit: image_buffer_ maybe? The callsites are confusing, you expect image_ to be a
GLImage.

[no sievers, 2014/03/13 20:50:15]

Done.

+  GLenum min_filter_;
+  GLenum mag_filter_;
+  GLenum wrap_s_;
+  GLenum wrap_t_;
+  GLenum usage_;
+  bool immutable_;
+  LevelInfos level_infos_;
+};
+
+}  // namespage gles2
+}  // namespace gpu
+
+#endif  // GPU_COMMAND_BUFFER_SERVICE_TEXTURE_DEFINITION_H_