diff --git a/apps/emqx/src/emqx_shared_sub.erl b/apps/emqx/src/emqx_shared_sub.erl
index bd9c16206..3d14dddd0 100644
--- a/apps/emqx/src/emqx_shared_sub.erl
+++ b/apps/emqx/src/emqx_shared_sub.erl
@@ -67,6 +67,11 @@
     code_change/3
 ]).
 
+%% Internal exports (RPC)
+-export([
+    init_monitors/0
+]).
+
 -export_type([strategy/0]).
 
 -type strategy() ::
@@ -336,7 +341,7 @@ subscribers(Group, Topic) ->
 init([]) ->
     ok = mria:wait_for_tables([?TAB]),
     {ok, _} = mnesia:subscribe({table, ?TAB, simple}),
-    {atomic, PMon} = mria:transaction(?SHARED_SUB_SHARD, fun init_monitors/0),
+    {atomic, PMon} = mria:transaction(?SHARED_SUB_SHARD, fun ?MODULE:init_monitors/0),
     ok = emqx_tables:new(?SHARED_SUBS, [protected, bag]),
     ok = emqx_tables:new(?ALIVE_SUBS, [protected, set, {read_concurrency, true}]),
     ok = emqx_tables:new(?SHARED_SUBS_ROUND_ROBIN_COUNTER, [public, set, {write_concurrency, true}]),