Type profiler by intercepting 'new' and 'delete' expressions.

third_party/tcmalloc/chromium/src/type_profiler_map.cc

Index: third_party/tcmalloc/chromium/src/type_profiler_map.cc
diff --git a/third_party/tcmalloc/chromium/src/type_profiler_map.cc b/third_party/tcmalloc/chromium/src/type_profiler_map.cc
new file mode 100644
index 0000000000000000000000000000000000000000..9827b748e94479c56c6f111fce0e753e475bbe52
--- /dev/null
+++ b/third_party/tcmalloc/chromium/src/type_profiler_map.cc
@@ -0,0 +1,113 @@
+// Copyright 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.
+
+#include <config.h>
+
+#include <new>
+#include <typeinfo>
+

[Ryan Sleevi, 2012/09/13 09:13:25]

missing stddef.h (<new> only pulls in std::size_t)

[Dai Mikurube (NOT FULLTIME), 2012/09/13 10:45:05]

Done.

+#include <gperftools/type_profiler_map.h>
+
+#include "addressmap-inl.h"
+#include "base/logging.h"
+#include "base/low_level_alloc.h"
+#include "base/spinlock.h"
+#include "tcmalloc_guard.h"
+
+namespace base {
+namespace type_profiler {
+
+namespace {
+
+const TCMallocGuard tcmalloc_initializer;
+
+//----------------------------------------------------------------------
+// A struct to store size and type_info of an object
+//----------------------------------------------------------------------
+
+struct ObjectInfo {
+ public:
+  ObjectInfo(): size(0), type(NULL) {}
+  ObjectInfo(unsigned int size_arg, const std::type_info* type_arg)
+      : size(size_arg),
+        type(type_arg) {
+  }
+
+  unsigned int size;
+  const std::type_info* type;
+};
+
+//----------------------------------------------------------------------
+// Locking
+//----------------------------------------------------------------------
+
+SpinLock g_type_profiler_lock(SpinLock::LINKER_INITIALIZED);

[Ryan Sleevi, 2012/09/13 09:13:25]

It is unfortunate, and perhaps meritous of future work, that this effectively
serializes all allocation/deallocations to block on the spin lock, given that
TCmalloc is so good at keeping track of thread-local storage.

I don't think it's a blocker for this change, but if you're trying to avoid
negatively impacting perf while collecting data, I believe it would be good to
consider the use of thread locals, rather than system globals, in the future.

[Dai Mikurube (NOT FULLTIME), 2012/09/13 10:45:05]

Yeah, I know.  I'll try that in future, but TCMalloc's heap-profiler also uses
such lock: RecordAlloc and RecordFree in heap-profiler.cc.  I should also fix
them at that time. ;)

+
+//----------------------------------------------------------------------
+// Simple allocator for type_info map's internal memory
+//----------------------------------------------------------------------
+
+LowLevelAlloc::Arena* g_type_profiler_map_memory = NULL;
+
+void* TypeProfilerMalloc(size_t bytes) {
+  return LowLevelAlloc::AllocWithArena(bytes, g_type_profiler_map_memory);
+}
+
+void TypeProfilerFree(void* p) {
+  LowLevelAlloc::Free(p);
+}
+
+//----------------------------------------------------------------------
+// Profiling control/state data
+//----------------------------------------------------------------------
+
+AddressMap<ObjectInfo>* g_type_profiler_map = NULL;
+
+//----------------------------------------------------------------------
+// Manage type_info map
+//----------------------------------------------------------------------
+
+void InitializeTypeProfilerMemory() {
+  if (g_type_profiler_map_memory != NULL) {
+    RAW_DCHECK(g_type_profiler_map != NULL, "TypeProfilerMap is NULL");
+    return;
+  }
+
+  g_type_profiler_map_memory =
+      LowLevelAlloc::NewArena(0, LowLevelAlloc::DefaultArena());
+
+  g_type_profiler_map =
+      new(TypeProfilerMalloc(sizeof(*g_type_profiler_map)))
+          AddressMap<ObjectInfo>(TypeProfilerMalloc, TypeProfilerFree);
+}
+
+}  // namespace
+
+void InsertType(void* address, unsigned int size, const std::type_info& type) {
+  SpinLockHolder lock(&g_type_profiler_lock);
+  InitializeTypeProfilerMemory();
+
+  g_type_profiler_map->Insert(address, ObjectInfo(size, &type));
+}
+
+void EraseType(void* address) {
+  SpinLockHolder lock(&g_type_profiler_lock);
+  InitializeTypeProfilerMemory();
+
+  ObjectInfo obj;
+  g_type_profiler_map->FindAndRemove(address, &obj);
+}
+
+const std::type_info* LookupType(const void* address) {
+  SpinLockHolder lock(&g_type_profiler_lock);
+  InitializeTypeProfilerMemory();
+
+  const ObjectInfo* found = g_type_profiler_map->Find(address);
+  if (found == NULL)
+    return NULL;
+  return found->type;
+}
+
+}  // namespace type_profiler
+}  // namespace base