diff --git a/lib/filterx/filterx-expr.c b/lib/filterx/filterx-expr.c
index 922ed11acb..0877aad112 100644
--- a/lib/filterx/filterx-expr.c
+++ b/lib/filterx/filterx-expr.c
@@ -65,7 +65,7 @@ filterx_expr_free_method(FilterXExpr *self)
 void
 filterx_expr_init_instance(FilterXExpr *self)
 {
-  self->ref_cnt = 1;
+  g_atomic_counter_set(&self->ref_cnt, 1);
   self->free_fn = filterx_expr_free_method;
 }
 
@@ -83,7 +83,7 @@ filterx_expr_ref(FilterXExpr *self)
   if (!self)
     return NULL;
 
-  self->ref_cnt++;
+  g_atomic_counter_inc(&self->ref_cnt);
   return self;
 }
 
@@ -93,7 +93,7 @@ filterx_expr_unref(FilterXExpr *self)
   if (!self)
     return;
 
-  if (--self->ref_cnt == 0)
+  if (g_atomic_counter_dec_and_test(&self->ref_cnt))
     {
       self->free_fn(self);
       g_free(self);
diff --git a/lib/filterx/filterx-expr.h b/lib/filterx/filterx-expr.h
index fbf8bc7ceb..d5b3c59b13 100644
--- a/lib/filterx/filterx-expr.h
+++ b/lib/filterx/filterx-expr.h
@@ -26,10 +26,11 @@
 
 #include "filterx-object.h"
 #include "cfg-lexer.h"
+#include "atomic.h"
 
 struct _FilterXExpr
 {
-  guint32 ref_cnt;
+  GAtomicCounter ref_cnt;
   const gchar *type;
   guint32 ignore_falsy_result:1, suppress_from_trace:1;