cc: Add RasterWorkerPool class.

cc/raster_worker.h

+// Copyright 2012 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 CC_RASTER_WORKER_H_
+#define CC_RASTER_WORKER_H_
+
+#include <string>
+
+#include "base/callback.h"
+#include "base/threading/thread.h"
+#include "cc/rendering_stats.h"
+#include "cc/scoped_ptr_vector.h"
+#include "ui/gfx/rect.h"
+
+namespace skia {
+class LazyPixelRef;
+}
+
+namespace cc {
+class PicturePileImpl;
+
+class RasterWorker {

[nduca, 2012/12/19 04:46:50]

RasterThreadPool? Worker implies that it is only one thread.

[reveman, 2012/12/27 15:26:58]

Right. I made it RasterWorkerPool in latest patch, which is somewhat consistent
with base::SequencedWorkerPool.

+ public:
+  explicit RasterWorker(size_t num_raster_threads);
+  virtual ~RasterWorker();
+
+  static scoped_ptr<RasterWorker> Create(size_t num_raster_threads) {
+    return make_scoped_ptr(new RasterWorker(num_raster_threads));
+  }
+
+  bool IsBusy();
+
+  void PostRasterTaskAndReply(PicturePileImpl* picture_pile,
+                              uint8_t* buffer,
+                              const gfx::Rect& rect,
+                              float contents_scale,
+                              const base::Closure& reply);
+  void PostImageDecodingTaskAndReply(skia::LazyPixelRef* pixel_ref,
+                                     const base::Closure& reply);
+
+  void GetRenderingStats(RenderingStats* stats);
+
+ private:
+  class Thread : public base::Thread {
+   public:
+    Thread(const std::string name);
+    virtual ~Thread();
+
+    int num_pending_tasks() const { return num_pending_tasks_; }
+
+   private:
+    friend class RasterWorker;
+
+    int num_pending_tasks_;
+
+    DISALLOW_COPY_AND_ASSIGN(Thread);
+  };
+
+  class PendingTaskComparator {
+   public:
+    bool operator() (const Thread* a, const Thread* b) const {
+      return a->num_pending_tasks() < b->num_pending_tasks();
+    }
+  };
+
+  typedef base::Callback<void(RenderingStats* stats)> TaskCallback;
+
+  void PostTaskAndReply(const TaskCallback& task, const base::Closure& reply);
+  void RunTaskOnRasterThread(const TaskCallback& task, RenderingStats* stats);
+  void OnTaskCompleted(Thread* thread,
+                       RenderingStats* stats,
+                       const base::Closure& reply);
+
+  typedef ScopedPtrVector<Thread> ThreadVector;
+  ThreadVector raster_threads_;
+
+  RenderingStats rendering_stats_;
+
+  DISALLOW_COPY_AND_ASSIGN(RasterWorker);
+};
+
+}  // namespace cc
+
+#endif  // CC_RASTER_WORKER_H_