Use RB_VM_LOCKING

Author: nobu

class.c

@@ -446,8 +446,7 @@ push_subclass_entry_to_list(VALUE super, VALUE klass, bool is_module)
     entry = ZALLOC(rb_subclass_entry_t);
     entry->klass = klass;
 
-    RB_VM_LOCK_ENTER();
-    {
+    RB_VM_LOCKING() {
         anchor = RCLASS_WRITABLE_SUBCLASSES(super);
         VM_ASSERT(anchor);
         ns_subclasses = (rb_ns_subclasses_t *)anchor->ns_subclasses;
@@ -464,7 +463,6 @@ push_subclass_entry_to_list(VALUE super, VALUE klass, bool is_module)
         entry->prev = head;
         st_insert(tbl, namespace_subclasses_tbl_key(ns), (st_data_t)entry);
     }
-    RB_VM_LOCK_LEAVE();
 
     if (is_module) {
         RCLASS_WRITE_NS_MODULE_SUBCLASSES(klass, anchor->ns_subclasses);

gc.c

@@ -2280,11 +2280,9 @@ classext_fields_hash_memsize(rb_classext_t *ext, bool prime, VALUE namespace, vo
 {
     size_t *size = (size_t *)arg;
     size_t count;
-    RB_VM_LOCK_ENTER();
-    {
+    RB_VM_LOCKING() {
         count = rb_st_table_size((st_table *)RCLASSEXT_FIELDS(ext));
     }
-    RB_VM_LOCK_LEAVE();
     // class IV sizes are allocated as powers of two
     *size += SIZEOF_VALUE << bit_length(count);
 }
@@ -4570,8 +4568,7 @@ ruby_gc_set_params(void)
 void
 rb_objspace_reachable_objects_from(VALUE obj, void (func)(VALUE, void *), void *data)
 {
-    RB_VM_LOCK_ENTER();
-    {
+    RB_VM_LOCKING() {
         if (rb_gc_impl_during_gc_p(rb_gc_get_objspace())) rb_bug("rb_objspace_reachable_objects_from() is not supported while during GC");
 
         if (!RB_SPECIAL_CONST_P(obj)) {
@@ -4587,7 +4584,6 @@ rb_objspace_reachable_objects_from(VALUE obj, void (func)(VALUE, void *), void *
             vm->gc.mark_func_data = prev_mfd;
         }
     }
-    RB_VM_LOCK_LEAVE();
 }
 
 struct root_objects_data {