File 4551-Preserve-applications-order-on-ensure_all_started.patch of Package erlang
From b744d4cab0d3a4632e5dcfff4656dc18f495188e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jos=C3=A9=20Valim?= <jose.valim@dashbit.co>
Date: Thu, 2 Mar 2023 12:37:17 +0100
Subject: [PATCH] Preserve applications order on ensure_all_started
This commit also trims down the internal graph
by keeping only applications with a mod callback
in concurrent mode.
---
lib/kernel/src/application.erl | 96 ++++++++++++++++------------------
1 file changed, 45 insertions(+), 51 deletions(-)
diff --git a/lib/kernel/src/application.erl b/lib/kernel/src/application.erl
index 093cde5c65..6d6bac949e 100644
--- a/lib/kernel/src/application.erl
+++ b/lib/kernel/src/application.erl
@@ -142,26 +142,26 @@ ensure_all_started(Application, Type) ->
ensure_all_started(Application, Type, Mode) when is_atom(Application) ->
ensure_all_started([Application], Type, Mode);
ensure_all_started(Applications, Type, Mode) when is_list(Applications) ->
- case ensure_all_enqueued(Applications, [], #{}, []) of
- {ok, DAG, _Pending} ->
- ForTraversal = maps:to_list(DAG),
- case Mode of
- concurrent ->
- ReqIDs = gen_server:reqids_new(),
- concurrent_dag_start(ForTraversal, ReqIDs, [], [], Type);
- serial ->
- serial_dag_start(ForTraversal, [], [], [], Type)
- end;
- ErrorAppReason ->
- ErrorAppReason
+ Opts = #{type => Type, mode => Mode},
+
+ case enqueue_or_start(Applications, [], #{}, [], [], Opts) of
+ {ok, DAG, _Pending, Started} when Mode =:= concurrent ->
+ ReqIDs = gen_server:reqids_new(),
+ concurrent_dag_start(maps:to_list(DAG), ReqIDs, [], Started, Type);
+ {ok, DAG, _Pending, Started} when Mode =:= serial ->
+ 0 = map_size(DAG),
+ {ok, lists:reverse(Started)};
+ {error, AppReason, Started} ->
+ _ = [stop(Name) || Name <- Started],
+ {error, AppReason}
end.
-ensure_all_enqueued([App | Apps], Optional, DAG, Pending)
+enqueue_or_start([App | Apps], Optional, DAG, Pending, Started, Opts)
when is_map_key(App, DAG) ->
%% We already traversed the application, so only add it as pending
- ensure_all_enqueued(Apps, Optional, DAG, [App | Pending]);
+ enqueue_or_start(Apps, Optional, DAG, [App | Pending], Started, Opts);
-ensure_all_enqueued([App | Apps], Optional, DAG, Pending) when is_atom(App) ->
+enqueue_or_start([App | Apps], Optional, DAG, Pending, Started, Opts) when is_atom(App) ->
%% In case the app is already running, we just skip it instead
%% of attempting to start all of its children - which would
%% have already been loaded and started anyway.
@@ -169,60 +169,54 @@ ensure_all_enqueued([App | Apps], Optional, DAG, Pending) when is_atom(App) ->
false ->
case ensure_loaded(App) of
{ok, Name} ->
- case enqueue_app(Name, App, DAG) of
- {ok, NewDAG} ->
- NewPending = [App | Pending],
- ensure_all_enqueued(Apps, Optional, NewDAG, NewPending);
- ErrorAppReason ->
- ErrorAppReason
+ case enqueue_or_start_app(Name, App, DAG, Pending, Started, Opts) of
+ {ok, NewDAG, NewPending, NewStarted} ->
+ enqueue_or_start(Apps, Optional, NewDAG, NewPending, NewStarted, Opts);
+ ErrorAppReasonStarted ->
+ ErrorAppReasonStarted
end;
{error, {"no such file or directory", _} = Reason} ->
case lists:member(App, Optional) of
true ->
- ensure_all_enqueued(Apps, Optional, DAG, Pending);
+ enqueue_or_start(Apps, Optional, DAG, Pending, Started, Opts);
false ->
- {error, {App, Reason}}
+ {error, {App, Reason}, Started}
end;
{error, Reason} ->
- {error, {App, Reason}}
+ {error, {App, Reason}, Started}
end;
true ->
- ensure_all_enqueued(Apps, Optional, DAG, Pending)
+ enqueue_or_start(Apps, Optional, DAG, Pending, Started, Opts)
end;
-ensure_all_enqueued([], _Optional, DAG, Pending) ->
- {ok, DAG, Pending}.
+enqueue_or_start([], _Optional, DAG, Pending, Started, _Opts) ->
+ {ok, DAG, Pending, Started}.
-enqueue_app(Name, App, DAG) ->
+enqueue_or_start_app(Name, App, DAG, Pending, Started, Opts) ->
+ #{type := Type, mode := Mode} = Opts,
{ok, ChildApps} = get_key(Name, applications),
{ok, OptionalApps} = get_key(Name, optional_applications),
-
- case ensure_all_enqueued(ChildApps, OptionalApps, DAG, []) of
- {ok, NewDAG, Pending} ->
- {ok, NewDAG#{App => Pending}};
- ErrorAppReason ->
- ErrorAppReason
- end.
-
-serial_dag_start([{App, Children} | Rest], Acc, Done, Started, Type) ->
- case Children -- Done of
- [] ->
+ {ok, Mod} = get_key(Name, mod),
+
+ %% If the application has no dependencies and we are either
+ %% on serial mode or the app does not have a module callback,
+ %% we start it immediately. At the end of serial mode, the DAG
+ %% is always empty.
+ case enqueue_or_start(ChildApps, OptionalApps, DAG, [], Started, Opts) of
+ {ok, NewDAG, NewPending, NewStarted}
+ when NewPending =:= [], (Mode =:= serial) or (Mod =:= []) ->
case application_controller:start_application(App, Type) of
ok ->
- serial_dag_start(Rest, Acc, [App | Done], [App | Started], Type);
+ {ok, NewDAG, Pending, [App | NewStarted]};
{error, {already_started, App}} ->
- serial_dag_start(Rest, Acc, [App | Done], Started, Type);
+ {ok, NewDAG, Pending, NewStarted};
{error, Reason} ->
- _ = [stop(Name) || Name <- Started],
- {error, {App, Reason}}
+ {error, {App, Reason}, NewStarted}
end;
- NewChildren ->
- NewAcc = [{App, NewChildren} | Acc],
- serial_dag_start(Rest, NewAcc, Done, Started, Type)
- end;
-serial_dag_start([], [], _Done, Started, _Type) ->
- {ok, lists:reverse(Started)};
-serial_dag_start([], Acc, Done, Started, Type) ->
- serial_dag_start(Acc, [], Done, Started, Type).
+ {ok, NewDAG, NewPending, NewStarted} ->
+ {ok, NewDAG#{App => NewPending}, [App | Pending], NewStarted};
+ ErrorAppReasonStarted ->
+ ErrorAppReasonStarted
+ end.
concurrent_dag_start([], ReqIDs, _Done, Started, _Type) ->
wait_all_enqueued(ReqIDs, Started, false);
--
2.35.3
