--- old/src/hotspot/share/runtime/handshake.cpp	2017-10-23 17:10:26.644192178 +0200
+++ new/src/hotspot/share/runtime/handshake.cpp	2017-10-23 17:10:26.220178244 +0200
@@ -75,6 +75,9 @@
     target->set_handshake_operation(_op);
   }
 
+  // This method returns true for threads completed their operation
+  // and true for threads canceled their operation.
+  // A cancellation can happen if the thread is exiting.
   bool poll_for_completed_thread() { return _op->thread_has_completed(); }
 
   bool handshake_has_timed_out(jlong start_time);