src/share/vm/oops/objArrayKlass.cpp

@@ -32,19 +32,19 @@
 #include "gc/shared/specialized_oop_closures.hpp"
 #include "memory/iterator.inline.hpp"
 #include "memory/metadataFactory.hpp"
 #include "memory/resourceArea.hpp"
 #include "memory/universe.inline.hpp"
+#include "oops/arrayKlass.inline.hpp"
 #include "oops/instanceKlass.hpp"
 #include "oops/klass.inline.hpp"
 #include "oops/objArrayKlass.inline.hpp"
 #include "oops/objArrayOop.inline.hpp"
 #include "oops/oop.inline.hpp"
 #include "oops/symbol.hpp"
 #include "runtime/handles.inline.hpp"
 #include "runtime/mutexLocker.hpp"
-#include "runtime/orderAccess.inline.hpp"
 #include "utilities/copy.hpp"
 #include "utilities/macros.hpp"
 
 ObjArrayKlass* ObjArrayKlass::allocate(ClassLoaderData* loader_data, int n, KlassHandle klass_handle, Symbol* name, TRAPS) {
   assert(ObjArrayKlass::header_size() <= InstanceKlass::header_size(),

@@ -319,11 +319,12 @@
 
   assert(dimension() <= n, "check order of chain");
   int dim = dimension();
   if (dim == n) return this;
 
-  if (higher_dimension() == NULL) {
+  // lock-free read needs acquire semantics
+  if (higher_dimension_acquire() == NULL) {
     if (or_null)  return NULL;
 
     ResourceMark rm;
     JavaThread *jt = (JavaThread *)THREAD;
     {

@@ -337,12 +338,12 @@
         // Create multi-dim klass object and link them together
         Klass* k =
           ObjArrayKlass::allocate_objArray_klass(class_loader_data(), dim + 1, this, CHECK_NULL);
         ObjArrayKlass* ak = ObjArrayKlass::cast(k);
         ak->set_lower_dimension(this);
-        OrderAccess::storestore();
-        set_higher_dimension(ak);
+        // use 'release' to pair with lock-free load
+        release_set_higher_dimension(ak);
         assert(ak->is_objArray_klass(), "incorrect initialization of ObjArrayKlass");
       }
     }
   } else {
     CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops());