Disk cache: Remove all non essential synchronization from the cache destructor.

net/disk_cache/backend_impl.h

-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Copyright (c) 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.
 
 // See net/disk_cache/disk_cache.h for the public interface of the cache.
 
 #ifndef NET_DISK_CACHE_BACKEND_IMPL_H_
 #define NET_DISK_CACHE_BACKEND_IMPL_H_
 #pragma once
 
 #include "base/file_path.h"
@@ skipping 37 matching lines @@
   BackendImpl(const FilePath& path, uint32 mask,
               base::MessageLoopProxy* cache_thread, net::NetLog* net_log);
   virtual ~BackendImpl();
 
   // Returns a new backend with the desired flags. See the declaration of
   // CreateCacheBackend().
   static int CreateBackend(const FilePath& full_path, bool force,
                            int max_bytes, net::CacheType type,
                            uint32 flags, base::MessageLoopProxy* thread,
                            net::NetLog* net_log, Backend** backend,
-                           const net::CompletionCallback& callback);
+                           const CompletionCallback& callback);
 
   // Performs general initialization for this current instance of the cache.
-  int Init(const net::CompletionCallback& callback);
+  int Init(const CompletionCallback& callback);
 
   // Performs the actual initialization and final cleanup on destruction.
   int SyncInit();
   void CleanupCache();
 
   // Same behavior as OpenNextEntry but walks the list from back to front.
   int OpenPrevEntry(void** iter, Entry** prev_entry,
-                    const net::CompletionCallback& callback);
+                    const CompletionCallback& callback);
 
   // Synchronous implementation of the asynchronous interface.
   int SyncOpenEntry(const std::string& key, Entry** entry);
   int SyncCreateEntry(const std::string& key, Entry** entry);
   int SyncDoomEntry(const std::string& key);
   int SyncDoomAllEntries();
   int SyncDoomEntriesBetween(const base::Time initial_time,
                              const base::Time end_time);
   int SyncDoomEntriesSince(const base::Time initial_time);
   int SyncOpenNextEntry(void** iter, Entry** next_entry);
@@ skipping 12 matching lines @@
 
   // Sets the cache type for this backend.
   void SetType(net::CacheType type);
 
   // Returns the full name for an external storage file.
   FilePath GetFileName(Addr address) const;
 
   // Returns the actual file used to store a given (non-external) address.
   MappedFile* File(Addr address);
 
-  InFlightBackendIO* background_queue() {
-    return &background_queue_;
-  }
+  // Returns a weak pointer to the background queue.
+  base::WeakPtr<InFlightBackendIO> GetBackgroundQueue();
 
   // Creates an external storage file.
   bool CreateExternalFile(Addr* address);
 
   // Creates a new storage block of size block_count.
   bool CreateBlock(FileType block_type, int block_count,
                    Addr* block_address);
 
   // Deletes a given storage block. deep set to true can be used to zero-fill
   // the related storage in addition of releasing the related block.
@@ skipping 115 matching lines @@
   // Sets the eviction algorithm to version 2.
   void SetNewEviction();
 
   // Sets an explicit set of BackendFlags.
   void SetFlags(uint32 flags);
 
   // Clears the counter of references to test handling of corruptions.
   void ClearRefCountForTest();
 
   // Sends a dummy operation through the operation queue, for unit tests.
-  int FlushQueueForTest(const net::CompletionCallback& callback);
+  int FlushQueueForTest(const CompletionCallback& callback);
 
   // Runs the provided task on the cache thread. The task will be automatically
   // deleted after it runs.
   int RunTaskForTest(const base::Closure& task,
-                     const net::CompletionCallback& callback);
+                     const CompletionCallback& callback);
 
   // Trims an entry (all if |empty| is true) from the list of deleted
   // entries. This method should be called directly on the cache thread.
   void TrimForTest(bool empty);
 
   // Trims an entry (all if |empty| is true) from the list of deleted
   // entries. This method should be called directly on the cache thread.
   void TrimDeletedListForTest(bool empty);
 
   // Performs a simple self-check, and returns the number of dirty items
   // or an error code (negative value).
   int SelfCheck();
 
   // Backend implementation.
   virtual int32 GetEntryCount() const OVERRIDE;
   virtual int OpenEntry(const std::string& key, Entry** entry,
-                        const net::CompletionCallback& callback) OVERRIDE;
+                        const CompletionCallback& callback) OVERRIDE;
   virtual int CreateEntry(const std::string& key, Entry** entry,
-                          const net::CompletionCallback& callback) OVERRIDE;
+                          const CompletionCallback& callback) OVERRIDE;
   virtual int DoomEntry(const std::string& key,
-                        const net::CompletionCallback& callback) OVERRIDE;
-  virtual int DoomAllEntries(const net::CompletionCallback& callback) OVERRIDE;
-  virtual int DoomEntriesBetween(
-      const base::Time initial_time,
-      const base::Time end_time,
-      const net::CompletionCallback& callback) OVERRIDE;
-  virtual int DoomEntriesSince(
-      const base::Time initial_time,
-      const net::CompletionCallback& callback) OVERRIDE;
+                        const CompletionCallback& callback) OVERRIDE;
+  virtual int DoomAllEntries(const CompletionCallback& callback) OVERRIDE;
+  virtual int DoomEntriesBetween(const base::Time initial_time,
+                                 const base::Time end_time,
+                                 const CompletionCallback& callback) OVERRIDE;
+  virtual int DoomEntriesSince(const base::Time initial_time,
+                               const CompletionCallback& callback) OVERRIDE;
   virtual int OpenNextEntry(void** iter, Entry** next_entry,
-                            const net::CompletionCallback& callback) OVERRIDE;
+                            const CompletionCallback& callback) OVERRIDE;
   virtual void EndEnumeration(void** iter) OVERRIDE;
   virtual void GetStats(StatsItems* stats) OVERRIDE;
   virtual void OnExternalCacheHit(const std::string& key) OVERRIDE;
 
  private:
   typedef base::hash_map<CacheAddr, EntryImpl*> EntriesMap;
 
   // Creates a new backing file for the cache index.
   bool CreateBackingStore(disk_cache::File* file);
   bool InitBackingStore(bool* file_created);
@@ skipping 105 matching lines @@
 
   DISALLOW_COPY_AND_ASSIGN(BackendImpl);
 };
 
 // Returns the preferred max cache size given the available disk space.
 NET_EXPORT_PRIVATE int PreferedCacheSize(int64 available);
 
 }  // namespace disk_cache
 
 #endif  // NET_DISK_CACHE_BACKEND_IMPL_H_