From 865463b67c433b40210458e306a5ed77402989e8 Mon Sep 17 00:00:00 2001 From: Hans Bolinder Date: Wed, 27 Feb 2019 16:01:45 +0100 Subject: kernel: Remove some obsolete code in the global module erlang:monitor_node() is asynchronous as of Erlang/OTP 21.0. Use that fact to remove no longer needed code in the global module. --- lib/kernel/src/global.erl | 80 +++++++++++++++-------------------------------- 1 file changed, 25 insertions(+), 55 deletions(-) (limited to 'lib/kernel/src/global.erl') diff --git a/lib/kernel/src/global.erl b/lib/kernel/src/global.erl index a38522eb5c..5bb56f2de6 100644 --- a/lib/kernel/src/global.erl +++ b/lib/kernel/src/global.erl @@ -1,7 +1,7 @@ %% %% %CopyrightBegin% %% -%% Copyright Ericsson AB 1996-2017. All Rights Reserved. +%% Copyright Ericsson AB 1996-2019. 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. @@ -125,16 +125,12 @@ %%% There are also ETS tables used for bookkeeping of locks and names %%% (the first position is the key): %%% -%%% global_locks (set): {ResourceId, LockRequesterId, [{Pid,RPid,ref()]} +%%% global_locks (set): {ResourceId, LockRequesterId, [{Pid,ref()]} %%% Pid is locking ResourceId, ref() is the monitor ref. -%%% RPid =/= Pid if there is an extra process calling erlang:monitor(). -%%% global_names (set): {Name, Pid, Method, RPid, ref()} +%%% global_names (set): {Name, Pid, Method, ref()} %%% Registered names. ref() is the monitor ref. -%%% RPid =/= Pid if there is an extra process calling erlang:monitor(). %%% global_names_ext (set): {Name, Pid, RegNode} %%% External registered names (C-nodes). -%%% (The RPid:s can be removed when/if erlang:monitor() returns before -%%% trying to connect to the other node.) %%% %%% Helper tables: %%% global_pid_names (bag): {Pid, Name} | {ref(), Name} @@ -310,7 +306,7 @@ re_register_name(Name, Pid, Method0) when is_pid(Pid) -> -spec registered_names() -> [Name] when Name :: term(). registered_names() -> - MS = ets:fun2ms(fun({Name,_Pid,_M,_RP,_R}) -> Name end), + MS = ets:fun2ms(fun({Name,_Pid,_M,_R}) -> Name end), ets:select(global_names, MS). %%----------------------------------------------------------------- @@ -1235,7 +1231,7 @@ ins_name_ext(Name, Pid, Method, RegNode, FromPidOrNode, ExtraInfo, S0) -> where(Name) -> case ets:lookup(global_names, Name) of - [{_Name, Pid, _Method, _RPid, _Ref}] -> + [{_Name, Pid, _Method, _Ref}] -> if node(Pid) == node() -> case is_process_alive(Pid) of true -> Pid; @@ -1272,10 +1268,10 @@ can_set_lock({ResourceId, LockRequesterId}) -> end. insert_lock({ResourceId, LockRequesterId}=Id, Pid, PidRefs, S) -> - {RPid, Ref} = do_monitor(Pid), + Ref = erlang:monitor(process, Pid), true = ets:insert(global_pid_ids, {Pid, ResourceId}), true = ets:insert(global_pid_ids, {Ref, ResourceId}), - Lock = {ResourceId, LockRequesterId, [{Pid,RPid,Ref} | PidRefs]}, + Lock = {ResourceId, LockRequesterId, [{Pid,Ref} | PidRefs]}, true = ets:insert(global_locks, Lock), trace_message(S, {ins_lock, node(Pid)}, [Id, Pid]). @@ -1293,10 +1289,9 @@ handle_del_lock({ResourceId, LockReqId}, Pid, S0) -> _ -> S0 end. -remove_lock(ResourceId, LockRequesterId, Pid, [{Pid,RPid,Ref}], Down, S0) -> +remove_lock(ResourceId, LockRequesterId, Pid, [{Pid,Ref}], Down, S0) -> ?trace({remove_lock_1, {id,ResourceId},{pid,Pid}}), true = erlang:demonitor(Ref, [flush]), - kill_monitor_proc(RPid, Pid), true = ets:delete(global_locks, ResourceId), true = ets:delete_object(global_pid_ids, {Pid, ResourceId}), true = ets:delete_object(global_pid_ids, {Ref, ResourceId}), @@ -1309,9 +1304,8 @@ remove_lock(ResourceId, LockRequesterId, Pid, [{Pid,RPid,Ref}], Down, S0) -> remove_lock(ResourceId, LockRequesterId, Pid, PidRefs0, _Down, S) -> ?trace({remove_lock_2, {id,ResourceId},{pid,Pid}}), PidRefs = case lists:keyfind(Pid, 1, PidRefs0) of - {Pid, RPid, Ref} -> + {Pid, Ref} -> true = erlang:demonitor(Ref, [flush]), - kill_monitor_proc(RPid, Pid), true = ets:delete_object(global_pid_ids, {Ref, ResourceId}), lists:keydelete(Pid, 1, PidRefs0); @@ -1324,11 +1318,6 @@ remove_lock(ResourceId, LockRequesterId, Pid, PidRefs0, _Down, S) -> trace_message(S, {rem_lock, node(Pid)}, [{ResourceId, LockRequesterId}, Pid]). -kill_monitor_proc(Pid, Pid) -> - ok; -kill_monitor_proc(RPid, _Pid) -> - exit(RPid, kill). - do_ops(Ops, ConnNode, Names_ext, ExtraInfo, S0) -> ?trace({do_ops, {ops,Ops}}), @@ -1394,8 +1383,8 @@ sync_other(Node, N) -> % exit(normal). insert_global_name(Name, Pid, Method, FromPidOrNode, ExtraInfo, S) -> - {RPid, Ref} = do_monitor(Pid), - true = ets:insert(global_names, {Name, Pid, Method, RPid, Ref}), + Ref = erlang:monitor(process, Pid), + true = ets:insert(global_names, {Name, Pid, Method, Ref}), true = ets:insert(global_pid_names, {Pid, Name}), true = ets:insert(global_pid_names, {Ref, Name}), case lock_still_set(FromPidOrNode, ExtraInfo, S) of @@ -1437,7 +1426,7 @@ extra_info(Tag, ExtraInfo) -> del_name(Ref, S) -> NameL = [Name || {_, Name} <- ets:lookup(global_pid_names, Ref), - {_, _Pid, _Method, _RPid, Ref1} <- + {_, _Pid, _Method, Ref1} <- ets:lookup(global_names, Name), Ref1 =:= Ref], case NameL of @@ -1450,24 +1439,23 @@ del_name(Ref, S) -> %% Keeps the entry in global_names for whereis_name/1. delete_global_name_keep_pid(Name, S) -> case ets:lookup(global_names, Name) of - [{Name, Pid, _Method, RPid, Ref}] -> - delete_global_name2(Name, Pid, RPid, Ref, S); + [{Name, Pid, _Method, Ref}] -> + delete_global_name2(Name, Pid, Ref, S); [] -> S end. delete_global_name2(Name, S) -> case ets:lookup(global_names, Name) of - [{Name, Pid, _Method, RPid, Ref}] -> + [{Name, Pid, _Method, Ref}] -> true = ets:delete(global_names, Name), - delete_global_name2(Name, Pid, RPid, Ref, S); + delete_global_name2(Name, Pid, Ref, S); [] -> S end. -delete_global_name2(Name, Pid, RPid, Ref, S) -> +delete_global_name2(Name, Pid, Ref, S) -> true = erlang:demonitor(Ref, [flush]), - kill_monitor_proc(RPid, Pid), delete_global_name(Name, Pid), ?trace({delete_global_name,{item,Name},{pid,Pid}}), true = ets:delete_object(global_pid_names, {Pid, Name}), @@ -1929,9 +1917,9 @@ reset_node_state(Node) -> %% from the same partition. exchange_names([{Name, Pid, Method} | Tail], Node, Ops, Res) -> case ets:lookup(global_names, Name) of - [{Name, Pid, _Method, _RPid2, _Ref2}] -> + [{Name, Pid, _Method, _Ref2}] -> exchange_names(Tail, Node, Ops, Res); - [{Name, Pid2, Method2, _RPid2, _Ref2}] when node() < Node -> + [{Name, Pid2, Method2, _Ref2}] when node() < Node -> %% Name clash! Add the result of resolving to Res(olved). %% We know that node(Pid) =/= node(), so we don't %% need to link/unlink to Pid. @@ -1960,7 +1948,7 @@ exchange_names([{Name, Pid, Method} | Tail], Node, Ops, Res) -> Op = {delete, Name}, exchange_names(Tail, Node, [Op | Ops], [Op | Res]) end; - [{Name, _Pid2, _Method, _RPid, _Ref}] -> + [{Name, _Pid2, _Method, _Ref}] -> %% The other node will solve the conflict. exchange_names(Tail, Node, Ops, Res); _ -> @@ -2036,7 +2024,7 @@ pid_is_locking(Pid, PidRefs) -> delete_lock(Ref, S0) -> Locks = pid_locks(Ref), F = fun({ResourceId, LockRequesterId, PidRefs}, S) -> - {Pid, _RPid, Ref} = lists:keyfind(Ref, 3, PidRefs), + {Pid, Ref} = lists:keyfind(Ref, 2, PidRefs), remove_lock(ResourceId, LockRequesterId, Pid, PidRefs, true, S) end, lists:foldl(F, S0, Locks). @@ -2046,10 +2034,10 @@ pid_locks(Ref) -> ets:lookup(global_locks, ResourceId) end, ets:lookup(global_pid_ids, Ref)), [Lock || Lock = {_Id, _Req, PidRefs} <- L, - rpid_is_locking(Ref, PidRefs)]. + ref_is_locking(Ref, PidRefs)]. -rpid_is_locking(Ref, PidRefs) -> - lists:keyfind(Ref, 3, PidRefs) =/= false. +ref_is_locking(Ref, PidRefs) -> + lists:keyfind(Ref, 2, PidRefs) =/= false. handle_nodedown(Node, S) -> %% DOWN signals from monitors have removed locks and registered names. @@ -2062,7 +2050,7 @@ handle_nodedown(Node, S) -> get_names() -> ets:select(global_names, - ets:fun2ms(fun({Name, Pid, Method, _RPid, _Ref}) -> + ets:fun2ms(fun({Name, Pid, Method, _Ref}) -> {Name, Pid, Method} end)). @@ -2205,24 +2193,6 @@ unexpected_message(Message, What) -> %%% Utilities -%% When/if erlang:monitor() returns before trying to connect to the -%% other node this function can be removed. -do_monitor(Pid) -> - case (node(Pid) =:= node()) orelse lists:member(node(Pid), nodes()) of - true -> - %% Assume the node is still up - {Pid, erlang:monitor(process, Pid)}; - false -> - F = fun() -> - Ref = erlang:monitor(process, Pid), - receive - {'DOWN', Ref, process, Pid, _Info} -> - exit(normal) - end - end, - erlang:spawn_monitor(F) - end. - intersection(_, []) -> []; intersection(L1, L2) -> -- cgit v1.2.3