diff -r 7ed777a14094 -r c265860d5d45 src/hotspot/share/runtime/mutexLocker.hpp
--- a/src/hotspot/share/runtime/mutexLocker.hpp	Tue Sep 04 12:17:23 2018 +0200
+++ b/src/hotspot/share/runtime/mutexLocker.hpp	Tue Sep 04 12:18:35 2018 +0200
@@ -94,6 +94,7 @@
                                                  // non-Java threads.
 extern Mutex*   MarkStackFreeList_lock;          // Protects access to the global mark stack free list.
 extern Mutex*   MarkStackChunkList_lock;         // Protects access to the global mark stack chunk list.
+extern Mutex*   MonitoringSupport_lock;          // Protects updates to the serviceability memory pools.
 extern Mutex*   ParGCRareEvent_lock;             // Synchronizes various (rare) parallel GC ops.
 extern Mutex*   Compile_lock;                    // a lock held when Compilation is updating code (used to block CodeCache traversal, CHA updates, etc)
 extern Monitor* MethodCompileQueue_lock;         // a lock held when method compilations are enqueued, dequeued