1 files changed, 82 insertions, 0 deletions
diff --git a/erts/preloaded/src/erts_dirty_process_code_checker.erl b/erts/preloaded/src/erts_dirty_process_code_checker.erl
new file mode 100644
index 0000000000..911642082c
--- /dev/null
+++ b/erts/preloaded/src/erts_dirty_process_code_checker.erl
@@ -0,0 +1,82 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2016. 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_code_checker).
+
+-export([start/0]).
+
+%%
+%% The erts_dirty_process_code_checker 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 ->
+		handle_request(Request)
+	end,
+    msg_loop().
+
+check_process(Requester, Target, ReqId, Module) ->
+    Result = erts_internal:check_dirty_process_code(Target, Module),
+    Requester ! {check_process_code, ReqId, Result}.
+					  
+handle_request({Requester,
+		Target,
+		Prio,
+		{check_process_code,
+		 ReqId,
+		 Module,
+		 _Flags} = Op}) ->
+    %%
+    %% Target may have stopped executing dirty since the
+    %% initial request was made. Check its current state
+    %% and try to send the request if possible; otherwise,
+    %% check the dirty executing process and send the result...
+    %%
+    try
+	case erts_internal:is_process_executing_dirty(Target) of
+	    true ->
+		check_process(Requester, Target, ReqId, Module);
+	    false ->
+		case erts_internal:request_system_task(Requester,
+						       Target,
+						       Prio,
+						       Op) of
+		    ok ->
+			ok;
+		    dirty_execution ->
+			check_process(Requester, Target, ReqId, Module)
+		end
+	end
+    catch
+	_ : _ ->
+	    ok %% Ignore all failures; someone passed us garbage...
+    end;
+handle_request(_Garbage) ->
+    ignore.
+
+		    
+