cc/resources/tile_task_runner.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 CC_RESOURCES_TILE_TASK_RUNNER_H_
   6 #define CC_RESOURCES_TILE_TASK_RUNNER_H_
   7
   8 #include <bitset>
   9 #include <vector>
  10
  11 #include "base/callback.h"
  12 #include "cc/resources/resource_format.h"
  13 #include "cc/resources/task_graph_runner.h"
  14
  15 namespace cc {
  16 class ImageDecodeTask;
  17 class RasterTask;
  18 class Resource;
  19 class RasterBuffer;
  20
  21 class CC_EXPORT TileTaskClient {
  22  public:
  23   virtual scoped_ptr<RasterBuffer> AcquireBufferForRaster(
  24       const Resource* resource) = 0;
  25   virtual void ReleaseBufferForRaster(scoped_ptr<RasterBuffer> buffer) = 0;
  26
  27  protected:
  28   virtual ~TileTaskClient() {}
  29 };
  30
  31 class CC_EXPORT TileTask : public Task {
  32  public:
  33   typedef std::vector<scoped_refptr<TileTask>> Vector;
  34
  35   virtual void ScheduleOnOriginThread(TileTaskClient* client) = 0;
  36   virtual void CompleteOnOriginThread(TileTaskClient* client) = 0;
  37   virtual void RunReplyOnOriginThread() = 0;
  38
  39   // Type-checking downcast routines.
  40   virtual ImageDecodeTask* AsImageDecodeTask();
  41   virtual RasterTask* AsRasterTask();
  42
  43   void WillSchedule();
  44   void DidSchedule();
  45   bool HasBeenScheduled() const;
  46
  47   void WillComplete();
  48   void DidComplete();
  49   bool HasCompleted() const;
  50
  51  protected:
  52   TileTask();
  53   ~TileTask() override;
  54
  55   bool did_schedule_;
  56   bool did_complete_;
  57 };
  58
  59 class CC_EXPORT ImageDecodeTask : public TileTask {
  60  public:
  61   typedef std::vector<scoped_refptr<ImageDecodeTask>> Vector;
  62
  63   // Overridden from TileTask:
  64   ImageDecodeTask* AsImageDecodeTask() override;
  65
  66  protected:
  67   ImageDecodeTask();
  68   ~ImageDecodeTask() override;
  69 };
  70
  71 class CC_EXPORT RasterTask : public TileTask {
  72  public:
  73   typedef std::vector<scoped_refptr<RasterTask>> Vector;
  74
  75   // Overridden from TileTask:
  76   RasterTask* AsRasterTask() override;
  77
  78   const Resource* resource() const { return resource_; }
  79   const ImageDecodeTask::Vector& dependencies() const { return dependencies_; }
  80
  81  protected:
  82   RasterTask(const Resource* resource, ImageDecodeTask::Vector* dependencies);
  83   ~RasterTask() override;
  84
  85  private:
  86   const Resource* resource_;
  87   ImageDecodeTask::Vector dependencies_;
  88 };
  89
  90 // kNumberOfTaskSets must be greater or equal to the number of values in
  91 // TileManager::NamedTaskSet.
  92 // TODO(reveman): Use template specialization to make it easy for client code to
  93 // check at compile time that the number of supported task sets is correct.
  94 static const size_t kNumberOfTaskSets = 3;
  95 typedef size_t TaskSet;
  96 typedef std::bitset<kNumberOfTaskSets> TaskSetCollection;
  97
  98 class CC_EXPORT TileTaskRunnerClient {
  99  public:
 100   virtual void DidFinishRunningTileTasks(TaskSet task_set) = 0;
 101   virtual TaskSetCollection TasksThatShouldBeForcedToComplete() const = 0;
 102
 103  protected:
 104   virtual ~TileTaskRunnerClient() {}
 105 };
 106
 107 struct CC_EXPORT TileTaskQueue {
 108   struct CC_EXPORT Item {
 109     class TaskComparator {
 110      public:
 111       explicit TaskComparator(const RasterTask* task) : task_(task) {}
 112
 113       bool operator()(const Item& item) const { return item.task == task_; }
 114
 115      private:
 116       const RasterTask* task_;
 117     };
 118
 119     typedef std::vector<Item> Vector;
 120
 121     Item(RasterTask* task, const TaskSetCollection& task_sets);
 122     ~Item();
 123
 124     RasterTask* task;
 125     TaskSetCollection task_sets;
 126   };
 127
 128   TileTaskQueue();
 129   ~TileTaskQueue();
 130
 131   void Swap(TileTaskQueue* other);
 132   void Reset();
 133
 134   Item::Vector items;
 135 };
 136
 137 // This interface can be used to schedule and run tile tasks. The client will
 138 // be notified asynchronously when the set of tasks marked as "required for
 139 // activation" have finished running, when tasks marked "required for draw"
 140 // have finished running, and when all scheduled tasks have finished running.
 141 // The client can call CheckForCompletedTasks() at any time to dispatch
 142 // pending completion callbacks for all tasks that have finished running.
 143 class CC_EXPORT TileTaskRunner {
 144  public:
 145   // Set the client instance to be notified when finished running tasks.
 146   virtual void SetClient(TileTaskRunnerClient* client) = 0;
 147
 148   // Tells the worker pool to shutdown after canceling all previously scheduled
 149   // tasks. Reply callbacks are still guaranteed to run when
 150   // CheckForCompletedTasks() is called.
 151   virtual void Shutdown() = 0;
 152
 153   // Schedule running of tile tasks in |queue| and all dependencies.
 154   // Previously scheduled tasks that are not in |queue| will be canceled unless
 155   // already running. Once scheduled, reply callbacks are guaranteed to run for
 156   // all tasks even if they later get canceled by another call to
 157   // ScheduleTasks().
 158   virtual void ScheduleTasks(TileTaskQueue* queue) = 0;
 159
 160   // Check for completed tasks and dispatch reply callbacks.
 161   virtual void CheckForCompletedTasks() = 0;
 162
 163   // Returns the format to use for the tiles.
 164   virtual ResourceFormat GetResourceFormat() = 0;
 165
 166  protected:
 167   virtual ~TileTaskRunner() {}
 168 };
 169
 170 }  // namespace cc
 171
 172 #endif  // CC_RESOURCES_TILE_TASK_RUNNER_H_