tracing: add dump provider for malloc heap profiler

base/trace_event/malloc_dump_provider.h

 // Copyright 2015 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_TRACE_EVENT_MALLOC_DUMP_PROVIDER_H_
 #define BASE_TRACE_EVENT_MALLOC_DUMP_PROVIDER_H_
 
 #include <istream>
 
 #include "base/macros.h"
+#include "base/memory/scoped_ptr.h"
 #include "base/memory/singleton.h"
+#include "base/synchronization/lock.h"
+#include "base/threading/platform_thread.h"
 #include "base/trace_event/memory_dump_provider.h"
 #include "build/build_config.h"
 
 #if defined(OS_LINUX) || defined(OS_ANDROID) || \
     (defined(OS_MACOSX) && !defined(OS_IOS))
 #define MALLOC_MEMORY_TRACING_SUPPORTED
 #endif
 
 namespace base {
 namespace trace_event {
 
+class AllocationRegister;
+
 // Dump provider which collects process-wide memory stats.
 class BASE_EXPORT MallocDumpProvider : public MemoryDumpProvider {
  public:
   // Name of the allocated_objects dump. Use this to declare suballocator dumps
   // from other dump providers.
   static const char kAllocatedObjects[];
 
   static MallocDumpProvider* GetInstance();
 
   // MemoryDumpProvider implementation.
   bool OnMemoryDump(const MemoryDumpArgs& args,
                     ProcessMemoryDump* pmd) override;
 
+  void OnHeapProfilingEnabled(bool enabled) override;
+
+  // For heap profiling.
+  void InsertAllocation(void* address, size_t size);
+  void RemoveAllocation(void* address);
+
  private:
   friend struct DefaultSingletonTraits<MallocDumpProvider>;
 
   MallocDumpProvider();
   ~MallocDumpProvider() override;
 
+  // For heap profiling.
+  bool heap_profiler_enabled_;
+  scoped_ptr<AllocationRegister> allocation_register_;
+  Lock allocation_register_lock_;
+
+  // When in OnMemoryDump(), this contains the current thread ID.
+  // This is to prevent re-entrancy in the heap profiler when the heap dump
+  // generation is malloc/new-ing for its own bookeeping data structures.
+  PlatformThreadId tid_dumping_heap_;
+
   DISALLOW_COPY_AND_ASSIGN(MallocDumpProvider);
 };
 
 }  // namespace trace_event
 }  // namespace base
 
 #endif  // BASE_TRACE_EVENT_MALLOC_DUMP_PROVIDER_H_