Record Chrome trace events in tcmalloc heap profiles

base/debug/trace_memory.h

+// Copyright 2013 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_DEBUG_TRACE_MEMORY_H_
+#define BASE_DEBUG_TRACE_MEMORY_H_
+
+#include "base/base_export.h"
+
+namespace base {
+
+class BASE_EXPORT ScopedTraceMemory {
+ public:
+  ScopedTraceMemory(const char* category);
+  ~ScopedTraceMemory();
+
+  static int GetStackIndexForTest();
+};
+
+BASE_EXPORT void TraceMemoryStart();
+BASE_EXPORT void TraceMemoryDump();
+// Caller owns the char* and must release it with free().
+BASE_EXPORT char* TraceMemoryDumpAsString();
+BASE_EXPORT void TraceMemoryStop();
+
+}  // namespace base
+
+// Make local variables with unique names based on the line number. Note that
+// the extra level of redirection is needed.
+#define INTERNAL_TRACE_MEMORY_ID3(line) trace_memory_unique_##line
+#define INTERNAL_TRACE_MEMORY_ID2(line) INTERNAL_TRACE_MEMORY_ID3(line)
+#define INTERNAL_TRACE_MEMORY_ID INTERNAL_TRACE_MEMORY_ID2(__LINE__)
+
+// Generates a unique local variable name.
+// TODO(jamescook): Make it record both category and name.
+#define TRACE_MEMORY(category, name) \
+  base::ScopedTraceMemory INTERNAL_TRACE_MEMORY_ID(name);
+
+// A special trace name that allows us to ignore memory allocations inside
+// the memory dump system itself. The allocations are recorded, but the
+// visualizer skips them. Must match the value in heap.js.
+#define TRACE_MEMORY_IGNORE "trace-memory-ignore"
+
+#endif  // BASE_DEBUG_TRACE_MEMORY_H_