gpu/command_buffer/service/command_buffer_service.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef GPU_COMMAND_BUFFER_SERVICE_COMMAND_BUFFER_SERVICE_H_
   6 #define GPU_COMMAND_BUFFER_SERVICE_COMMAND_BUFFER_SERVICE_H_
   7
   8 #include "base/callback.h"
   9 #include "base/memory/shared_memory.h"
  10 #include "gpu/command_buffer/common/command_buffer.h"
  11 #include "gpu/command_buffer/common/command_buffer_shared.h"
  12
  13 namespace gpu {
  14
  15 class TransferBufferManagerInterface;
  16
  17 class GPU_EXPORT CommandBufferServiceBase : public CommandBuffer {
  18  public:
  19   // Sets the current get offset. This can be called from any thread.
  20   virtual void SetGetOffset(int32 get_offset) = 0;
  21
  22   // Get the transfer buffer associated with an ID. Returns a null buffer for
  23   // ID 0.
  24   virtual scoped_refptr<gpu::Buffer> GetTransferBuffer(int32 id) = 0;
  25
  26   // Allows the reader to update the current token value.
  27   virtual void SetToken(int32 token) = 0;
  28
  29   // Allows the reader to set the current parse error.
  30   virtual void SetParseError(error::Error) = 0;
  31
  32   // Allows the reader to set the current context lost reason.
  33   // NOTE: if calling this in conjunction with SetParseError,
  34   // call this first.
  35   virtual void SetContextLostReason(error::ContextLostReason) = 0;
  36 };
  37
  38 // An object that implements a shared memory command buffer and a synchronous
  39 // API to manage the put and get pointers.
  40 class GPU_EXPORT CommandBufferService : public CommandBufferServiceBase {
  41  public:
  42   typedef base::Callback<bool(int32)> GetBufferChangedCallback;
  43   explicit CommandBufferService(
  44       TransferBufferManagerInterface* transfer_buffer_manager);
  45   virtual ~CommandBufferService();
  46
  47   // CommandBuffer implementation:
  48   virtual bool Initialize() OVERRIDE;
  49   virtual State GetLastState() OVERRIDE;
  50   virtual int32 GetLastToken() OVERRIDE;
  51   virtual void Flush(int32 put_offset) OVERRIDE;
  52   virtual void WaitForTokenInRange(int32 start, int32 end) OVERRIDE;
  53   virtual void WaitForGetOffsetInRange(int32 start, int32 end) OVERRIDE;
  54   virtual void SetGetBuffer(int32 transfer_buffer_id) OVERRIDE;
  55   virtual scoped_refptr<Buffer> CreateTransferBuffer(size_t size,
  56                                                      int32* id) OVERRIDE;
  57   virtual void DestroyTransferBuffer(int32 id) OVERRIDE;
  58
  59   // CommandBufferServiceBase implementation:
  60   virtual void SetGetOffset(int32 get_offset) OVERRIDE;
  61   virtual scoped_refptr<Buffer> GetTransferBuffer(int32 id) OVERRIDE;
  62   virtual void SetToken(int32 token) OVERRIDE;
  63   virtual void SetParseError(error::Error error) OVERRIDE;
  64   virtual void SetContextLostReason(error::ContextLostReason) OVERRIDE;
  65
  66   // Sets a callback that is called whenever the put offset is changed. When
  67   // called with sync==true, the callback must not return until some progress
  68   // has been made (unless the command buffer is empty), i.e. the get offset
  69   // must have changed. It need not process the entire command buffer though.
  70   // This allows concurrency between the writer and the reader while giving the
  71   // writer a means of waiting for the reader to make some progress before
  72   // attempting to write more to the command buffer. Takes ownership of
  73   // callback.
  74   virtual void SetPutOffsetChangeCallback(const base::Closure& callback);
  75   // Sets a callback that is called whenever the get buffer is changed.
  76   virtual void SetGetBufferChangeCallback(
  77       const GetBufferChangedCallback& callback);
  78   virtual void SetParseErrorCallback(const base::Closure& callback);
  79
  80   // Setup the shared memory that shared state should be copied into.
  81   void SetSharedStateBuffer(scoped_ptr<BufferBacking> shared_state_buffer);
  82
  83   // Copy the current state into the shared state transfer buffer.
  84   void UpdateState();
  85
  86   // Registers an existing shared memory object and get an ID that can be used
  87   // to identify it in the command buffer.
  88   bool RegisterTransferBuffer(int32 id, scoped_ptr<BufferBacking> buffer);
  89
  90  private:
  91   int32 ring_buffer_id_;
  92   scoped_refptr<Buffer> ring_buffer_;
  93   scoped_ptr<BufferBacking> shared_state_buffer_;
  94   CommandBufferSharedState* shared_state_;
  95   int32 num_entries_;
  96   int32 get_offset_;
  97   int32 put_offset_;
  98   base::Closure put_offset_change_callback_;
  99   GetBufferChangedCallback get_buffer_change_callback_;
 100   base::Closure parse_error_callback_;
 101   TransferBufferManagerInterface* transfer_buffer_manager_;
 102   int32 token_;
 103   uint32 generation_;
 104   error::Error error_;
 105   error::ContextLostReason context_lost_reason_;
 106
 107   DISALLOW_COPY_AND_ASSIGN(CommandBufferService);
 108 };
 109
 110 }  // namespace gpu
 111
 112 #endif  // GPU_COMMAND_BUFFER_SERVICE_COMMAND_BUFFER_SERVICE_H_