Report memory retained by memory allocator internals.

base/allocator/allocator_extension.h

 // 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.
 
 #ifndef BASE_ALLOCATOR_ALLOCATOR_EXTENSION_H
 #define BASE_ALLOCATOR_ALLOCATOR_EXTENSION_H
 
 #include <stddef.h> // for size_t
 
 #include "base/allocator/allocator_extension_thunks.h"
 #include "base/base_export.h"
 #include "build/build_config.h"
 
 namespace base {
 namespace allocator {
 
-// Request the allocator to report value of its internal state variable.
+// Request the allocator to report value of its waste memory size.
+// Waste size corresponds to memory that has been allocated from the OS but
+// not passed up to the application. It e.g. includes memory retained by free
+// lists, internal data, chunks padding, etc.
 //
-// |name| name of the variable
-// |value| pointer to the returned value, must be not NULL.
-// Returns true if the value has been returned, false if a variable with such
-// name does not exist.
-BASE_EXPORT bool GetProperty(const char* name, size_t* value);
+// |size| pointer to the returned value, must be not NULL.
+// Returns true if the value has been returned, false otherwise.
+BASE_EXPORT bool GetAllocatorWasteSize(size_t* size);
 
 // Request that the allocator print a human-readable description of the current
 // state of the allocator into a null-terminated string in the memory segment
 // buffer[0,buffer_length-1].
 //
 // |buffer| must point to a valid piece of memory
 // |buffer_length| must be > 0.
 BASE_EXPORT void GetStats(char* buffer, int buffer_length);
 
 // Request that the allocator release any free memory it knows about to the
 // system.
 BASE_EXPORT void ReleaseFreeMemory();
 
 
 // These settings allow specifying a callback used to implement the allocator
 // extension functions.  These are optional, but if set they must only be set
 // once.  These will typically called in an allocator-specific initialization
 // routine.
 //
 // No threading promises are made.  The caller is responsible for making sure
 // these pointers are set before any other threads attempt to call the above
 // functions.
-BASE_EXPORT void SetGetPropertyFunction(
-    thunks::GetPropertyFunction get_property_function);
+BASE_EXPORT void SetGetAllocatorWasteSizeFunction(
+    thunks::GetAllocatorWasteSizeFunction get_allocator_waste_size_function);
 
 BASE_EXPORT void SetGetStatsFunction(
     thunks::GetStatsFunction get_stats_function);
 
 BASE_EXPORT void SetReleaseFreeMemoryFunction(
     thunks::ReleaseFreeMemoryFunction release_free_memory_function);
 
 }  // namespace allocator
 }  // namespace base
 
 #endif