Merge pull request #1740 from rickard-green/rickard/signals/OTP-14589

Implementation of true asynchronous signaling between processes

5 files changed, 150 insertions, 96 deletions

diff --git a/erts/preloaded/src/Makefile b/erts/preloaded/src/Makefile
index a2872082f2..4333f6643a 100644
--- a/erts/preloaded/src/Makefile
+++ b/erts/preloaded/src/Makefile
@@ -1,7 +1,7 @@
 # 
 # %CopyrightBegin%
 # 
-# Copyright Ericsson AB 2008-2016. All Rights Reserved.
+# Copyright Ericsson AB 2008-2018. 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.
@@ -47,7 +47,7 @@ PRE_LOADED_ERL_MODULES = \
 	erts_internal \
 	erl_tracer \
 	erts_literal_area_collector \
-	erts_dirty_process_code_checker
+	erts_dirty_process_signal_handler
 
 PRE_LOADED_BEAM_MODULES = \
 	prim_eval
diff --git a/erts/preloaded/src/erlang.erl b/erts/preloaded/src/erlang.erl
index 370ecdc3f6..6cfca68a56 100644
--- a/erts/preloaded/src/erlang.erl
+++ b/erts/preloaded/src/erlang.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 1996-2017. All Rights Reserved.
+%% Copyright Ericsson AB 1996-2018. 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.
@@ -31,7 +31,7 @@
 -export([localtime_to_universaltime/1]).
 -export([suspend_process/1]).
 -export([min/2, max/2]).
--export([dmonitor_node/3, dmonitor_p/2]).
+-export([dmonitor_node/3]).
 -export([delay_trap/2]).
 -export([set_cookie/2, get_cookie/0]).
 -export([nodes/0]).
@@ -122,7 +122,7 @@
 -export([delete_element/2]).
 -export([delete_module/1, demonitor/1, demonitor/2, display/1]).
 -export([display_nl/0, display_string/1, erase/0, erase/1]).
--export([error/1, error/2, exit/1, exit/2, external_size/1]).
+-export([error/1, error/2, exit/1, exit/2, exit_signal/2, external_size/1]).
 -export([external_size/2, finish_after_on_load/2, finish_loading/1, float/1]).
 -export([float_to_binary/1, float_to_binary/2,
 	 float_to_list/1, float_to_list/2, floor/1]).
@@ -786,6 +786,13 @@ exit(_Reason) ->
 exit(_Pid, _Reason) ->
     erlang:nif_error(undefined).
 
+%% exit_signal/2
+-spec erlang:exit_signal(Pid, Reason) -> true when
+      Pid :: pid() | port(),
+      Reason :: term().
+exit_signal(_Pid, _Reason) ->
+    erlang:nif_error(undefined).
+
 %% external_size/1
 -spec erlang:external_size(Term) -> non_neg_integer() when
       Term :: term().
@@ -1012,8 +1019,20 @@ group_leader() ->
 -spec group_leader(GroupLeader, Pid) -> true when
       GroupLeader :: pid(),
       Pid :: pid().
-group_leader(_GroupLeader, _Pid) ->
-    erlang:nif_error(undefined).
+group_leader(GroupLeader, Pid) ->
+    case case erts_internal:group_leader(GroupLeader, Pid) of
+             false ->
+                 Ref = erlang:make_ref(),
+                 erts_internal:group_leader(GroupLeader,
+                                            Pid,
+                                            Ref),
+                 receive {Ref, MsgRes} -> MsgRes end;
+             Res ->
+                 Res
+         end of
+        true -> true;
+        Error -> erlang:error(Error, [GroupLeader, Pid])
+    end.
 
 %% halt/0
 %% Shadowed by erl_bif_types: erlang:halt/0
@@ -3279,13 +3298,6 @@ dmonitor_node(Node, Flag, Opts) ->
 	    dmonitor_node(Node,Flag,[])
     end.
 
--spec erlang:dmonitor_p('process', pid() | {atom(),atom()}) -> reference().
-dmonitor_p(process, ProcSpec) ->
-    %% Only called when auto-connect attempt failed early in VM
-    Ref = erlang:make_ref(),
-    erlang:self() ! {'DOWN', Ref, process, ProcSpec, noconnection},
-    Ref.
-
 %%
 %% Trap function used when modified timing has been enabled.
 %%
diff --git a/erts/preloaded/src/erts_dirty_process_code_checker.erl b/erts/preloaded/src/erts_dirty_process_code_checker.erl
deleted file mode 100644
index 7d3fa264be..0000000000
--- a/erts/preloaded/src/erts_dirty_process_code_checker.erl
+++ /dev/null
@@ -1,81 +0,0 @@
-%%
-%% %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} = 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.
-
-		    
-	    
diff --git a/erts/preloaded/src/erts_dirty_process_signal_handler.erl b/erts/preloaded/src/erts_dirty_process_signal_handler.erl
new file mode 100644
index 0000000000..ab71790b9d
--- /dev/null
+++ b/erts/preloaded/src/erts_dirty_process_signal_handler.erl
@@ -0,0 +1,97 @@
+%%
+%% %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) of
+        true ->
+            ok;
+        false ->
+            %% 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) ->
+    case erts_internal:is_process_executing_dirty(Target) of
+        false ->
+            false;
+        true ->
+            _ = check_process(Requester, Target, ReqId, Module),
+            true
+    end.
+
+check_process(Requester, Target, ReqId, Module) ->
+    Result = erts_internal:check_dirty_process_code(Target, Module),
+    Requester ! {check_process_code, ReqId, Result}.
diff --git a/erts/preloaded/src/erts_internal.erl b/erts/preloaded/src/erts_internal.erl
index a51c0c4c0e..21f228395e 100644
--- a/erts/preloaded/src/erts_internal.erl
+++ b/erts/preloaded/src/erts_internal.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 2012-2017. All Rights Reserved.
+%% Copyright Ericsson AB 2012-2018. 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.
@@ -45,6 +45,8 @@
 -export([check_process_code/3]).
 -export([check_dirty_process_code/2]).
 -export([is_process_executing_dirty/1]).
+-export([dirty_process_handle_signals/1]).
+
 -export([release_literal_area_switch/0]).
 -export([purge_module/2]).
 
@@ -71,6 +73,8 @@
          gather_sched_wall_time_result/1,
 	 await_sched_wall_time_modifications/2]).
 
+-export([group_leader/2, group_leader/3]).
+
 %% Auto import name clash
 -export([check_process_code/1]).
 
@@ -306,6 +310,13 @@ check_dirty_process_code(_Pid,_Module) ->
 is_process_executing_dirty(_Pid) ->
     erlang:nif_error(undefined).
 
+-spec dirty_process_handle_signals(Pid) -> Res when
+      Pid :: pid(),
+      Res :: 'false' | 'true' | 'noproc' | 'normal' | 'more' | 'ok'.
+
+dirty_process_handle_signals(_Pid) ->
+    erlang:nif_error(undefined).
+
 -spec release_literal_area_switch() -> 'true' | 'false'.
 
 release_literal_area_switch() ->
@@ -574,3 +585,18 @@ sched_wall_time(Ref, N, Acc) ->
 	{Ref, SWTL} when erlang:is_list(SWTL) -> sched_wall_time(Ref, N-1, Acc ++ SWTL);
 	{Ref, SWT} -> sched_wall_time(Ref, N-1, [SWT|Acc])
     end.
+
+-spec erts_internal:group_leader(GL, Pid) -> true | false | badarg when
+      GL :: pid(),
+      Pid :: pid().
+
+group_leader(_GL, _Pid) ->
+    erlang:nif_error(undefined).
+
+-spec erts_internal:group_leader(GL, Pid, Ref) -> ok when
+      GL :: pid(),
+      Pid :: pid(),
+      Ref :: reference().
+
+group_leader(_GL, _Pid, _Ref) ->
+    erlang:nif_error(undefined).