From 2d374a3b0d1ee6a5a9e8b805d5ad3b93204e2227 Mon Sep 17 00:00:00 2001
From: "Zaiming (Stone) Shi" <zmstone@gmail.com>
Date: Fri, 8 Apr 2022 15:51:59 +0200
Subject: [PATCH] chore: no need for erlang:demonitor optimisation

---
 apps/emqx/src/emqx_pmon.erl | 17 ++---------------
 1 file changed, 2 insertions(+), 15 deletions(-)

diff --git a/apps/emqx/src/emqx_pmon.erl b/apps/emqx/src/emqx_pmon.erl
index 426b76da1..05007ccef 100644
--- a/apps/emqx/src/emqx_pmon.erl
+++ b/apps/emqx/src/emqx_pmon.erl
@@ -72,23 +72,10 @@ demonitor(Pid, PMon = ?PMON(Map)) ->
             PMon
     end.
 
-%% @doc Improved version of erlang:demonitor(Ref, [flush]).
-%% Only try to receive the 'DOWN' messages when it might have been sent.
 -spec demonitor(reference()) -> ok.
 demonitor(Ref) when is_reference(Ref) ->
-    case erlang:demonitor(Ref, [info]) of
-        true ->
-            %% succeeded
-            ok;
-        _ ->
-            %% '_', but not 'false' because this may change in the future according to OTP doc
-            receive
-                {'DOWN', Ref, process, _, _} ->
-                    ok
-            after 0 ->
-                ok
-            end
-    end.
+    _ = erlang:demonitor(Ref, [flush]),
+    ok.
 
 -spec find(pid(), pmon()) -> error | {ok, term()}.
 find(Pid, ?PMON(Map)) ->