--- old/src/hotspot/share/runtime/mutexLocker.cpp	2018-03-19 14:01:14.485610364 -0700
+++ new/src/hotspot/share/runtime/mutexLocker.cpp	2018-03-19 14:01:14.197611302 -0700
@@ -127,6 +127,8 @@
 Monitor* PeriodicTask_lock            = NULL;
 Monitor* RedefineClasses_lock         = NULL;
 
+Monitor* ThreadHeapSampler_lock       = NULL;
+
 #if INCLUDE_TRACE
 Mutex*   JfrStacktrace_lock           = NULL;
 Monitor* JfrMsg_lock                  = NULL;
@@ -283,6 +285,9 @@
   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       , PaddedMonitor, nonleaf,     false, Monitor::_safepoint_check_never);
+
   if (WhiteBoxAPI) {
     def(Compilation_lock           , PaddedMonitor, leaf,        false, Monitor::_safepoint_check_never);
   }