--- a/src/hotspot/share/gc/z/zCollectedHeap.cpp	Tue Oct 16 13:43:04 2018 +0200
+++ b/src/hotspot/share/gc/z/zCollectedHeap.cpp	Tue Oct 16 13:14:18 2018 +0200
@@ -23,6 +23,7 @@
 
 #include "precompiled.hpp"
 #include "gc/shared/gcHeapSummary.hpp"
+#include "gc/shared/suspendibleThreadSet.hpp"
 #include "gc/z/zCollectedHeap.hpp"
 #include "gc/z/zGlobals.hpp"
 #include "gc/z/zHeap.inline.hpp"
@@ -295,6 +296,14 @@
                              reserved_region().start() + max_capacity_in_words);
 }
 
+void ZCollectedHeap::safepoint_synchronize_begin() {
+  SuspendibleThreadSet::synchronize();
+}
+
+void ZCollectedHeap::safepoint_synchronize_end() {
+  SuspendibleThreadSet::desynchronize();
+}
+
 void ZCollectedHeap::prepare_for_verify() {
   // Does nothing
 }