gpu: Thread-safe command buffer state lookup.

gpu/command_buffer/client/context_support.h

 // Copyright 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.
 
 #ifndef GPU_COMMAND_BUFFER_CLIENT_CONTEXT_SUPPORT_H_
 #define GPU_COMMAND_BUFFER_CLIENT_CONTEXT_SUPPORT_H_
 
 #include <stdint.h>
 
 #include "base/callback.h"
 #include "ui/gfx/overlay_transform.h"
 
 namespace gfx {
 class Rect;
 class RectF;
 }
 
 namespace gpu {
 
 struct SyncToken;
 
 class ContextSupport {
  public:
   // Runs |callback| when a sync token is signalled.
   virtual void SignalSyncToken(const SyncToken& sync_token,
                                const base::Closure& callback) = 0;
 
+  // Returns true if the given fence sync has been released (executed) by the
+  // command buffer. This may be called from any thread.
+  virtual bool IsFenceSyncReleased(uint64_t release_count) = 0;
+
   // Runs |callback| when a query created via glCreateQueryEXT() has cleared
   // passed the glEndQueryEXT() point.
   virtual void SignalQuery(uint32_t query, const base::Closure& callback) = 0;
 
   // Indicates whether the context should aggressively free allocated resources.
   // If set to true, the context will purge all temporary resources when
   // flushed.
   virtual void SetAggressivelyFreeResources(
       bool aggressively_free_resources) = 0;
 
@@ skipping 20 matching lines @@
       const base::Callback<void(const char*, int32_t)>& callback) = 0;
 
  protected:
   ContextSupport() {}
   virtual ~ContextSupport() {}
 };
 
 }
 
 #endif  // GPU_COMMAND_BUFFER_CLIENT_CONTEXT_SUPPORT_H_