%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 2018. All Rights Reserved.
%%
%% Licensed under the Apache License, Version 2.0 (the "License");
%% you may not use this file except in compliance with the License.
%% You may obtain a copy of the License at
%%
%% http://www.apache.org/licenses/LICENSE-2.0
%%
%% Unless required by applicable law or agreed to in writing, software
%% distributed under the License is distributed on an "AS IS" BASIS,
%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
%% See the License for the specific language governing permissions and
%% limitations under the License.
%%
%% %CopyrightEnd%
%%
-module(erts_dirty_process_signal_handler).
-export([start/0]).
%%
%% The erts_dirty_process_signal_handler is started at
%% VM boot by the VM. It is a spawned as a system
%% process, i.e, the whole VM will terminate if
%% this process terminates.
%%
start() ->
process_flag(trap_exit, true),
msg_loop().
msg_loop() ->
_ = receive
Request ->
try
handle_request(Request)
catch
_ : _ ->
%% Ignore all failures;
%% someone passed us garbage...
ok
end
end,
msg_loop().
handle_request(Pid) when is_pid(Pid) ->
handle_incoming_signals(Pid, 0);
handle_request({Requester, Target, Prio,
{SysTaskOp, ReqId, Arg} = Op} = Request) ->
case handle_sys_task(Requester, Target, SysTaskOp, ReqId, Arg, 0) of
done ->
ok;
busy ->
self() ! Request;
normal ->
%% Target has stopped executing dirty since the
%% initial request was made. Dispatch the
%% request to target and let it handle it itself...
case erts_internal:request_system_task(Requester,
Target,
Prio,
Op) of
ok ->
ok;
dirty_execution ->
%% Ahh... It began executing dirty again...
handle_request(Request)
end
end;
handle_request(_Garbage) ->
ignore.
%%
%% ----------------------------------------------------------------------------
%%
handle_incoming_signals(Pid, 5) ->
self() ! Pid; %% Work with other requests for a while...
handle_incoming_signals(Pid, N) ->
case erts_internal:dirty_process_handle_signals(Pid) of
more -> handle_incoming_signals(Pid, N+1);
_Res -> ok
end.
handle_sys_task(Requester, Target, check_process_code, ReqId, Module, N) ->
case erts_internal:check_dirty_process_code(Target, Module) of
Bool when Bool == true; Bool == false ->
Requester ! {check_process_code, ReqId, Bool},
done;
busy ->
case N > 5 of
true ->
busy;
false ->
handle_sys_task(Requester, Target, check_process_code,
ReqId, Module, N+1)
end;
Res ->
Res
end.
