src/hotspot/share/gc/z/zBarrierSet.hpp

Concurrent class unloading

   virtual void on_thread_create(Thread* thread);
   virtual void on_thread_destroy(Thread* thread);
   virtual void on_thread_attach(JavaThread* thread);
   virtual void on_thread_detach(JavaThread* thread);
 
+  // nmethod entry barrier support
+  virtual bool needs_nmethod_entry_barrier() const;
+  virtual int nmethod_entry_barrier_state() const;
+  virtual ByteSize nmethod_entry_barrier_state_thread_offset() const;
+  virtual bool on_nmethod_entry_barrier(nmethod* nm, nmethodBarrier* nmbarrier);
+
   virtual void print_on(outputStream* st) const {}
 
   template <DecoratorSet decorators, typename BarrierSetT = ZBarrierSet>
   class AccessBarrier : public BarrierSet::AccessBarrier<decorators, BarrierSetT> {
   private: