Import Traceline, a Windows performance trace event logger.

tools/traceline/traceline/rdtsc.h

Index: tools/traceline/traceline/rdtsc.h
diff --git a/tools/traceline/traceline/rdtsc.h b/tools/traceline/traceline/rdtsc.h
new file mode 100755
index 0000000000000000000000000000000000000000..7c3cb1a967612967cdeae76405e0f91debabf57e
--- /dev/null
+++ b/tools/traceline/traceline/rdtsc.h
@@ -0,0 +1,43 @@
+// Copyright (c) 2009 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 TRACELINE_RDTSC_H_
+#define TRACELINE_RDTSC_H_
+
+#include <windows.h>
+#include <powrprof.h>
+
+#include <map>
+
+#include "logging.h"
+
+class RDTSCNormalizer {
+ public:
+  RDTSCNormalizer() { }
+  ~RDTSCNormalizer() { }
+
+  void Start() {
+    LARGE_INTEGER freq, now;
+    if (QueryPerformanceFrequency(&freq) == 0) {
+      NOTREACHED("");
+    }
+    freq_ = freq.QuadPart;
+
+    if (QueryPerformanceCounter(&now) == 0) {
+      NOTREACHED("");
+    }
+    start_ = now.QuadPart;
+  }
+
+  // Calculate the time from start for a given processor.
+  double MsFromStart(void* procid, __int64 stamp) {
+    return (stamp - start_) / (freq_ / 1000.0);
+  }
+
+ private:
+  __int64 freq_;
+  __int64 start_;
+};
+
+#endif  // TRACELINE_RDTSC_H_