--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/trace/traceEvent.hpp	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,130 @@
+/*
+ * Copyright (c) 2012, 2017, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+#ifndef SHARE_VM_TRACE_TRACEEVENT_HPP
+#define SHARE_VM_TRACE_TRACEEVENT_HPP
+
+#include "trace/traceTime.hpp"
+#include "utilities/macros.hpp"
+
+enum EventStartTime {
+  UNTIMED,
+  TIMED
+};
+
+#if INCLUDE_TRACE
+#include "trace/traceBackend.hpp"
+#include "tracefiles/traceEventIds.hpp"
+#include "utilities/ticks.hpp"
+
+template<typename T>
+class TraceEvent {
+ private:
+  bool _started;
+
+ protected:
+  jlong _startTime;
+  jlong _endTime;
+  DEBUG_ONLY(bool _committed;)
+
+  void set_starttime(const TracingTime& time) {
+    _startTime = time;
+  }
+
+  void set_endtime(const TracingTime& time) {
+    _endTime = time;
+  }
+
+  TraceEvent(EventStartTime timing=TIMED) :
+    _startTime(0),
+    _endTime(0),
+    _started(false)
+#ifdef ASSERT
+    , _committed(false)
+#endif
+  {
+    if (T::is_enabled()) {
+      _started = true;
+      if (TIMED == timing && !T::isInstant) {
+        static_cast<T*>(this)->set_starttime(Tracing::time());
+      }
+    }
+  }
+
+ public:
+  void set_starttime(const Ticks& time) {
+    _startTime = time.value();
+  }
+
+  void set_endtime(const Ticks& time) {
+    _endTime = time.value();
+  }
+
+  static bool is_enabled() {
+    return Tracing::is_event_enabled(T::eventId);
+  }
+
+  bool should_commit() {
+    return _started;
+  }
+
+  void commit() {
+    if (!should_commit()) {
+      return;
+    }
+    assert(!_committed, "event already committed");
+    if (_startTime == 0) {
+      static_cast<T*>(this)->set_starttime(Tracing::time());
+    } else if (_endTime == 0) {
+      static_cast<T*>(this)->set_endtime(Tracing::time());
+    }
+    if (static_cast<T*>(this)->should_write()) {
+      static_cast<T*>(this)->writeEvent();
+      DEBUG_ONLY(_committed = true;)
+    }
+  }
+
+  static TraceEventId id() {
+    return T::eventId;
+  }
+
+  static bool is_instant() {
+    return T::isInstant;
+  }
+
+  static bool is_requestable() {
+    return T::isRequestable;
+  }
+
+  static bool has_thread() {
+    return T::hasThread;
+  }
+
+  static bool has_stacktrace() {
+    return T::hasStackTrace;
+  }
+};
+
+#endif // INCLUDE_TRACE
+#endif // SHARE_VM_TRACE_TRACEEVENT_HPP