cc: Refactor OneCopyTileTaskWorkerPool.

cc/raster/staging_buffer_pool.h

Index: cc/raster/staging_buffer_pool.h
diff --git a/cc/raster/staging_buffer_pool.h b/cc/raster/staging_buffer_pool.h
new file mode 100644
index 0000000000000000000000000000000000000000..1b3f04604e23b7b6794ffe2f3580c8f3e4025c65
--- /dev/null
+++ b/cc/raster/staging_buffer_pool.h
@@ -0,0 +1,117 @@
+// Copyright 2016 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_STAGING_BUFFER_POOL_H_
+#define CC_RASTER_STAGING_BUFFER_POOL_H_
+
+#include <stdint.h>
+
+#include <deque>
+#include <set>
+
+#include "base/macros.h"
+#include "base/memory/weak_ptr.h"
+#include "base/synchronization/lock.h"
+#include "base/time/time.h"
+#include "base/trace_event/memory_dump_provider.h"
+#include "cc/output/context_provider.h"
+#include "cc/resources/resource_provider.h"
+
+namespace gpu {
+namespace gles2 {
+class GLES2Interface;
+}
+}
+
+namespace cc {
+class Resource;
+class RasterSource;
+class ResourcePool;
+
+struct StagingBuffer {
+  StagingBuffer(const gfx::Size& size, ResourceFormat format);
+  ~StagingBuffer();
+
+  void DestroyGLResources(gpu::gles2::GLES2Interface* gl);
+  void OnMemoryDump(base::trace_event::ProcessMemoryDump* pmd,
+                    ResourceFormat format,
+                    bool is_free) const;
+
+  const gfx::Size size;
+  const ResourceFormat format;
+  scoped_ptr<gfx::GpuMemoryBuffer> gpu_memory_buffer;
+  base::TimeTicks last_usage;
+  unsigned texture_id;
+  unsigned image_id;
+  unsigned query_id;
+  uint64_t content_id;
+};
+
+class CC_EXPORT StagingBufferPool
+    : public base::trace_event::MemoryDumpProvider {
+ public:
+  ~StagingBufferPool() final;
+
+  static scoped_ptr<StagingBufferPool> Create(
+      base::SequencedTaskRunner* task_runner,
+      ResourceProvider* resource_provider,
+      bool use_partial_raster,
+      int max_staging_buffer_usage_in_bytes);
+  void Shutdown();
+
+  // Overridden from base::trace_event::MemoryDumpProvider:
+  bool OnMemoryDump(const base::trace_event::MemoryDumpArgs& args,
+                    base::trace_event::ProcessMemoryDump* pmd) override;
+
+  scoped_ptr<StagingBuffer> AcquireStagingBuffer(const Resource* resource,
+                                                 uint64_t previous_content_id);
+  void ReleaseStagingBuffer(scoped_ptr<StagingBuffer> staging_buffer);
+
+ private:
+  StagingBufferPool(base::SequencedTaskRunner* task_runner,
+                    ResourceProvider* resource_provider,
+                    bool use_partial_raster,
+                    int max_staging_buffer_usage_in_bytes);
+
+  void AddStagingBuffer(const StagingBuffer* staging_buffer,
+                        ResourceFormat format);
+  void RemoveStagingBuffer(const StagingBuffer* staging_buffer);
+  void MarkStagingBufferAsFree(const StagingBuffer* staging_buffer);
+  void MarkStagingBufferAsBusy(const StagingBuffer* staging_buffer);
+
+  base::TimeTicks GetUsageTimeForLRUBuffer();
+  void ScheduleReduceMemoryUsage();
+  void ReduceMemoryUsage();
+  void ReleaseBuffersNotUsedSince(base::TimeTicks time);
+
+  scoped_ptr<base::trace_event::ConvertableToTraceFormat> StateAsValue() const;
+  void StagingStateAsValueInto(
+      base::trace_event::TracedValue* staging_state) const;
+
+  scoped_refptr<base::SequencedTaskRunner> task_runner_;
+  ResourceProvider* const resource_provider_;
+  const bool use_partial_raster_;
+
+  mutable base::Lock lock_;
+  // |lock_| must be acquired when accessing the following members.
+  using StagingBufferSet = std::set<const StagingBuffer*>;
+  StagingBufferSet buffers_;
+  using StagingBufferDeque = std::deque<scoped_ptr<StagingBuffer>>;
+  StagingBufferDeque free_buffers_;
+  StagingBufferDeque busy_buffers_;
+  const int max_staging_buffer_usage_in_bytes_;
+  int staging_buffer_usage_in_bytes_;
+  int free_staging_buffer_usage_in_bytes_;
+  const base::TimeDelta staging_buffer_expiration_delay_;
+  bool reduce_memory_usage_pending_;
+  base::Closure reduce_memory_usage_callback_;
+
+  base::WeakPtrFactory<StagingBufferPool> weak_ptr_factory_;
+
+  DISALLOW_COPY_AND_ASSIGN(StagingBufferPool);
+};
+
+}  // namespace cc
+
+#endif  // CC_RASTER_STAGING_BUFFER_POOL_H_