Split image decode cache limits into "working set" vs "cache" limits

cc/tiles/gpu_image_decode_cache.h

 // 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_TILES_GPU_IMAGE_DECODE_CACHE_H_
 #define CC_TILES_GPU_IMAGE_DECODE_CACHE_H_
 
 #include <memory>
 #include <unordered_map>
 #include <vector>
@@ skipping 85 matching lines @@
 //
 class CC_EXPORT GpuImageDecodeCache
     : public ImageDecodeCache,
       public base::trace_event::MemoryDumpProvider,
       public base::MemoryCoordinatorClient {
  public:
   enum class DecodeTaskType { PART_OF_UPLOAD_TASK, STAND_ALONE_DECODE_TASK };
 
   explicit GpuImageDecodeCache(ContextProvider* context,
                                ResourceFormat decode_format,
-                               size_t max_gpu_image_bytes);
+                               size_t max_working_set_bytes,
+                               size_t max_cache_bytes);
   ~GpuImageDecodeCache() override;
 
   // ImageDecodeCache overrides.
 
   // Finds the existing uploaded image for the provided DrawImage. Creates an
   // upload task to upload the image if an exsiting image does not exist.
   bool GetTaskForImageAndRef(const DrawImage& image,
                              const TracingInfo& tracing_info,
                              scoped_refptr<TileTask>* task) override;
   bool GetOutOfRasterDecodeTaskForImageAndRef(
@@ skipping 18 matching lines @@
   // Called by Decode / Upload tasks.
   void DecodeImage(const DrawImage& image);
   void UploadImage(const DrawImage& image);
 
   // Called by Decode / Upload tasks when tasks are finished.
   void OnImageDecodeTaskCompleted(const DrawImage& image,
                                   DecodeTaskType task_type);
   void OnImageUploadTaskCompleted(const DrawImage& image);
 
   // For testing only.
-  void SetCachedBytesLimitForTesting(size_t limit) {
+  void SetAllByteLimitsForTesting(size_t limit) {
     cached_bytes_limit_ = limit;
+    max_working_set_bytes_ = limit;
   }
   size_t GetBytesUsedForTesting() const { return bytes_used_; }
   size_t GetNumCacheEntriesForTesting() const {
     return persistent_cache_.size();
   }
   size_t GetDrawImageSizeForTesting(const DrawImage& image);
   void SetImageDecodingFailedForTesting(const DrawImage& image);
   bool DiscardableIsLockedForTesting(const DrawImage& image);
   bool IsInInUseCacheForTesting(const DrawImage& image) const;
 
@@ skipping 128 matching lines @@
 
   void RefImageDecode(const DrawImage& draw_image);
   void UnrefImageDecode(const DrawImage& draw_image);
   void RefImage(const DrawImage& draw_image);
   void UnrefImageInternal(const DrawImage& draw_image);
 
   // Called any time the ownership of an object changed. This includes changes
   // to ref-count or to orphaned status.
   void OwnershipChanged(const DrawImage& draw_image, ImageData* image_data);
 
-  // Ensures that the cache can hold an element of |required_size|, freeing
-  // unreferenced cache entries if necessary to make room.
+  // Ensures that the working set can hold an element of |required_size|,
+  // freeing unreferenced cache entries to make room.
   bool EnsureCapacity(size_t required_size);
-  bool CanFitSize(size_t size) const;
+  bool CanFitInWorkingSet(size_t size) const;
+  bool CanFitInCache(size_t size) const;
   bool ExceedsPreferredCount() const;
 
   void DecodeImageIfNecessary(const DrawImage& draw_image,
                               ImageData* image_data);
 
   scoped_refptr<GpuImageDecodeCache::ImageData> CreateImageData(
       const DrawImage& image);
   SkImageInfo CreateImageInfoForDrawImage(const DrawImage& draw_image,
                                           int upload_scale_mip_level) const;
 
@@ skipping 21 matching lines @@
   // |persistent_cache_| represents the long-lived cache, keeping a certain
   // budget of ImageDatas alive even when their ref count reaches zero.
   using PersistentCache = base::MRUCache<uint32_t, scoped_refptr<ImageData>>;
   PersistentCache persistent_cache_;
 
   // |in_use_cache_| represents the in-use (short-lived) cache. Entries are
   // cleaned up as soon as their ref count reaches zero.
   using InUseCache = std::unordered_map<InUseCacheKey, InUseCacheEntry>;
   InUseCache in_use_cache_;
 
-  const size_t normal_max_gpu_image_bytes_;
-  size_t cached_bytes_limit_ = normal_max_gpu_image_bytes_;
+  size_t max_working_set_bytes_;
+  const size_t normal_max_cache_bytes_;
+  size_t cached_bytes_limit_ = normal_max_cache_bytes_;
   size_t bytes_used_ = 0;
   base::MemoryState memory_state_ = base::MemoryState::NORMAL;
 
   // We can't release GPU backed SkImages without holding the context lock,
   // so we add them to this list and defer deletion until the next time the lock
   // is held.
   std::vector<sk_sp<SkImage>> images_pending_deletion_;
 };
 
 }  // namespace cc
 
 #endif  // CC_TILES_GPU_IMAGE_DECODE_CACHE_H_