src/hotspot/share/gc/shared/c1/barrierSetC1.cpp

@@ -133,20 +133,20 @@
   return atomic_add_at_resolved(access, value);
 }
 
 void BarrierSetC1::store_at_resolved(LIRAccess& access, LIR_Opr value) {
   DecoratorSet decorators = access.decorators();
-  bool is_volatile = (((decorators & MO_SEQ_CST) != 0) || AlwaysAtomicAccesses) && os::is_MP();
+  bool is_volatile = (((decorators & MO_SEQ_CST) != 0) || AlwaysAtomicAccesses);
   bool needs_patching = (decorators & C1_NEEDS_PATCHING) != 0;
   bool mask_boolean = (decorators & C1_MASK_BOOLEAN) != 0;
   LIRGenerator* gen = access.gen();
 
   if (mask_boolean) {
     value = gen->mask_boolean(access.base().opr(), value, access.access_emit_info());
   }
 
-  if (is_volatile && os::is_MP()) {
+  if (is_volatile) {
     __ membar_release();
   }
 
   LIR_PatchCode patch_code = needs_patching ? lir_patch_normal : lir_patch_none;
   if (is_volatile && !needs_patching) {

@@ -161,11 +161,11 @@
 }
 
 void BarrierSetC1::load_at_resolved(LIRAccess& access, LIR_Opr result) {
   LIRGenerator *gen = access.gen();
   DecoratorSet decorators = access.decorators();
-  bool is_volatile = (((decorators & MO_SEQ_CST) != 0) || AlwaysAtomicAccesses) && os::is_MP();
+  bool is_volatile = (((decorators & MO_SEQ_CST) != 0) || AlwaysAtomicAccesses);
   bool needs_patching = (decorators & C1_NEEDS_PATCHING) != 0;
   bool mask_boolean = (decorators & C1_MASK_BOOLEAN) != 0;
   bool in_native = (decorators & IN_NATIVE) != 0;
 
   if (support_IRIW_for_not_multiple_copy_atomic_cpu && is_volatile) {

@@ -179,11 +179,11 @@
     gen->volatile_field_load(access.resolved_addr()->as_address_ptr(), result, access.access_emit_info());
   } else {
     __ load(access.resolved_addr()->as_address_ptr(), result, access.access_emit_info(), patch_code);
   }
 
-  if (is_volatile && os::is_MP()) {
+  if (is_volatile) {
     __ membar_acquire();
   }
 
   /* Normalize boolean value returned by unsafe operation, i.e., value  != 0 ? value = true : value false. */
   if (mask_boolean) {