--- old/src/hotspot/share/runtime/vm_version.hpp	2018-07-19 11:58:53.913290401 +0100
+++ new/src/hotspot/share/runtime/vm_version.hpp	2018-07-19 11:58:53.070287863 +0100
@@ -58,6 +58,7 @@
   static int          _vm_build_number;
   static unsigned int _parallel_worker_threads;
   static bool         _parallel_worker_threads_initialized;
+  static unsigned int _data_cache_line_flush_size;
 
   static unsigned int nof_parallel_worker_threads(unsigned int num,
                                                   unsigned int dem,
@@ -139,6 +140,12 @@
     return _L1_data_cache_line_size;
   }
 
+  // the size in bytes of a data cache line flushed by a flush
+  // operation which should be a power of two
+  static unsigned int data_cache_line_flush_size() {
+    return _data_cache_line_flush_size;
+  }
+
   // ARCH specific policy for the BiasedLocking
   static bool use_biased_locking()  { return true; }