--- a/src/hotspot/share/runtime/mutexLocker.cpp	Mon Jun 11 15:28:24 2018 +0200
+++ b/src/hotspot/share/runtime/mutexLocker.cpp	Fri Jun 15 00:49:54 2018 -0700
@@ -131,6 +131,8 @@
 Monitor* PeriodicTask_lock            = NULL;
 Monitor* RedefineClasses_lock         = NULL;
 
+Mutex*   ThreadHeapSampler_lock       = NULL;
+
 #if INCLUDE_JFR
 Mutex*   JfrStacktrace_lock           = NULL;
 Monitor* JfrMsg_lock                  = NULL;
@@ -296,6 +298,9 @@
   def(CompileThread_lock           , PaddedMonitor, nonleaf+5,   false, Monitor::_safepoint_check_always);
   def(PeriodicTask_lock            , PaddedMonitor, nonleaf+5,   true,  Monitor::_safepoint_check_sometimes);
   def(RedefineClasses_lock         , PaddedMonitor, nonleaf+5,   true,  Monitor::_safepoint_check_always);
+
+  def(ThreadHeapSampler_lock       , PaddedMutex,   nonleaf,     false, Monitor::_safepoint_check_never);
+
   if (WhiteBoxAPI) {
     def(Compilation_lock           , PaddedMonitor, leaf,        false, Monitor::_safepoint_check_never);
   }