fix(sys_mon): guard before calling `erlang:port_info`

Sometimes, the `emqx_sys_mon:procinfo/1` might be called with
something that is not a port, like `[]`.  Not sure on the conditions
for this to happen.

```
2022-02-18T20:05:02.671592+00:00 [error] Generic server emqx_sys_mon terminating. Reason: {badarg,[{erlang,port_info,[[]],[{error_info,#{module => erl_erts_errors}}]},{emqx_sys_mon,portinfo,1,[{file,"/emqx/apps/emqx/src/emqx_sys_mon.erl"},{line,205}]},{emqx_sys_mon,'-handle_info/2-fun-5-',2,[{file,"/emqx/apps/emqx/src/emqx_sys_mon.erl"},{line,150}]},{emqx_sys_mon,suppress,3,[{file,"/emqx/apps/emqx/src/emqx_sys_mon.erl"},{line,184}]},{gen_server,try_dispatch,4,[{file,"gen_server.erl"},{line,695}]},{gen_server,handle_msg,6,[{file,"gen_server.erl"},{line,771}]},{proc_lib,wake_up,3,[{file,"proc_lib.erl"},{line,236}]}]}. Last message: {monitor,<0.7796.0>,busy_dist_port,[]}. State: #{events => [{busy_dist_port,#Port<0.127>}],timer => #Ref<0.2758388682.1853620226.133920>}.
```
This commit is contained in:
Thales Macedo Garitezi 2022-02-22 16:31:35 -03:00
parent f173a2f61f
commit d89925ce7b
No known key found for this signature in database
GPG Key ID: DD279F8152A9B6DD
2 changed files with 11 additions and 1 deletions

View File

@ -202,7 +202,12 @@ get_proc_lib_initial_call(Pid) ->
end.
portinfo(Port) ->
[{port, Port} | erlang:port_info(Port)].
PortInfo =
case is_port(Port) andalso erlang:port_info(Port) of
L when is_list(L) -> L;
_ -> []
end,
[{port, Port} | PortInfo].
safe_publish(Event, WarnMsg) ->
Topic = emqx_topic:systop(lists:concat(['sysmon/', Event])),

View File

@ -35,6 +35,11 @@
{self(), busy_port,
fmt("busy_port warning: suspid = ~p, port = ~p",
[self(), ?FAKE_PORT]), ?FAKE_PORT},
%% for the case when the port is missing, for some
%% reason.
{self(), busy_port,
fmt("busy_port warning: suspid = ~p, port = ~p",
[self(), []]), []},
{self(), busy_dist_port,
fmt("busy_dist_port warning: suspid = ~p, port = ~p",
[self(), ?FAKE_PORT]), ?FAKE_PORT},