diff a/src/hotspot/share/gc/z/zMarkStackAllocator.cpp b/src/hotspot/share/gc/z/zMarkStackAllocator.cpp
--- a/src/hotspot/share/gc/z/zMarkStackAllocator.cpp
+++ b/src/hotspot/share/gc/z/zMarkStackAllocator.cpp
@@ -164,11 +164,11 @@
   return magazine;
 }
 
 ZMarkStackMagazine* ZMarkStackAllocator::alloc_magazine() {
   // Try allocating from the free list first
-  ZMarkStackMagazine* const magazine = _freelist.pop_atomic();
+  ZMarkStackMagazine* const magazine = _freelist.pop();
   if (magazine != NULL) {
     return magazine;
   }
 
   // Allocate new magazine
@@ -179,7 +179,7 @@
 
   return create_magazine_from_space(addr, ZMarkStackMagazineSize);
 }
 
 void ZMarkStackAllocator::free_magazine(ZMarkStackMagazine* magazine) {
-  _freelist.push_atomic(magazine);
+  _freelist.push(magazine);
 }