content/renderer/gpu/frame_swap_message_queue.h

   1 // Copyright 2014 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 CONTENT_RENDERER_GPU_FRAME_SWAP_MESSAGE_QUEUE_H_
   6 #define CONTENT_RENDERER_GPU_FRAME_SWAP_MESSAGE_QUEUE_H_
   7
   8 #include <map>
   9 #include <vector>
  10
  11 #include "base/auto_reset.h"
  12 #include "base/memory/ref_counted.h"
  13 #include "base/memory/scoped_ptr.h"
  14 #include "base/memory/scoped_vector.h"
  15 #include "base/synchronization/lock.h"
  16 #include "cc/output/swap_promise.h"
  17 #include "content/common/content_export.h"
  18 #include "content/renderer/message_delivery_policy.h"
  19
  20 namespace IPC {
  21 class Message;
  22 };
  23
  24 namespace content {
  25
  26 class FrameSwapMessageSubQueue;
  27
  28 // Queue used to keep track of which IPC::Messages should be sent along with a
  29 // particular compositor frame swap.
  30 class CONTENT_EXPORT FrameSwapMessageQueue
  31     : public base::RefCountedThreadSafe<FrameSwapMessageQueue> {
  32  public:
  33   class CONTENT_EXPORT SendMessageScope {
  34    public:
  35     virtual ~SendMessageScope() {}
  36   };
  37
  38   FrameSwapMessageQueue();
  39
  40   // Queues message to be returned on a matching DrainMessages call.
  41   //
  42   // |policy| determines how messages are matched with DrainMessages calls.
  43   // |source_frame_number| frame number to queue |msg| for.
  44   // |msg| - message to queue. The method takes ownership of |msg|.
  45   // |is_first| - output parameter. Set to true if this was the first message
  46   //              enqueued for the given source_frame_number.
  47   void QueueMessageForFrame(MessageDeliveryPolicy policy,
  48                             int source_frame_number,
  49                             scoped_ptr<IPC::Message> msg,
  50                             bool* is_first);
  51
  52   // Returns true if there are no messages in the queue.
  53   bool Empty() const;
  54
  55   // Should be called when a successful swap occurs. The messages for that swap
  56   // can be obtained by calling DrainMessages.
  57   //
  58   // |source_frame_number| frame number for which the swap occurred.
  59   void DidSwap(int source_frame_number);
  60
  61   // Should be called when we know a swap will not occur. This also means we
  62   // won't be expecting a DrainMessages call.
  63   //
  64   // |source_frame_number| frame number for which the swap will not occur.
  65   // |reason| reason for the which the swap will not occur.
  66   // |messages| depending on |reason| it may make sense to deliver certain
  67   //            messages asynchronously. This vector will contain those
  68   //            messages.
  69   void DidNotSwap(int source_frame_number,
  70                   cc::SwapPromise::DidNotSwapReason reason,
  71                   ScopedVector<IPC::Message>* messages);
  72
  73   // A SendMessageScope object must be held by the caller when this method is
  74   // called.
  75   //
  76   // |messages| vector to store messages, it's not cleared, only appended to.
  77   //            The method will append messages queued for frame numbers lower
  78   //            or equal to |source_frame_number|
  79   void DrainMessages(ScopedVector<IPC::Message>* messages);
  80
  81   // SendMessageScope is used to make sure that messages sent from different
  82   // threads (impl/main) are scheduled in the right order on the IO threads.
  83   //
  84   // Returns an object that must be kept in scope till an IPC message containing
  85   // |messages| is sent.
  86   scoped_ptr<SendMessageScope> AcquireSendMessageScope();
  87
  88   static void TransferMessages(ScopedVector<IPC::Message>& source,
  89                                std::vector<IPC::Message>* dest);
  90
  91  private:
  92   friend class base::RefCountedThreadSafe<FrameSwapMessageQueue>;
  93
  94   FrameSwapMessageSubQueue* GetSubQueue(MessageDeliveryPolicy policy);
  95
  96   ~FrameSwapMessageQueue();
  97
  98   mutable base::Lock lock_;
  99   scoped_ptr<FrameSwapMessageSubQueue> visual_state_queue_;
 100   scoped_ptr<FrameSwapMessageSubQueue> swap_queue_;
 101   ScopedVector<IPC::Message> next_drain_messages_;
 102
 103   DISALLOW_COPY_AND_ASSIGN(FrameSwapMessageQueue);
 104 };
 105
 106 }  // namespace content
 107
 108 #endif  // CONTENT_RENDERER_GPU_FRAME_SWAP_MESSAGE_QUEUE_H_