File 2641-mnesia-Introduce-sync_asym_trans-protocol.patch of Package erlang
From edfeb5d9b7dcba2380f629b5a41cbab65cd40cb8 Mon Sep 17 00:00:00 2001
From: Dan Gudmundsson <dgud@erlang.org>
Date: Thu, 25 Jul 2019 11:07:28 +0200
Subject: [PATCH 1/2] mnesia: Introduce sync_asym_trans protocol
Transactions with sticky locks could with async_asym transactions be
committed in the wrong order, since asym transaction are spawned on
the remote nodes.
See ERL-768.
---
lib/mnesia/src/mnesia_locker.erl | 2 ++
lib/mnesia/src/mnesia_tm.erl | 75 ++++++++++++++++++++++++----------------
lib/mnesia/test/mt | 38 +++++++++++++++-----
3 files changed, 78 insertions(+), 37 deletions(-)
diff --git a/lib/mnesia/src/mnesia_locker.erl b/lib/mnesia/src/mnesia_locker.erl
index f68626413e..0222c5b1a0 100644
--- a/lib/mnesia/src/mnesia_locker.erl
+++ b/lib/mnesia/src/mnesia_locker.erl
@@ -774,10 +774,12 @@ do_sticky_lock(Tid, Store, {Tab, Key} = Oid, Lock) ->
N = node(),
receive
{?MODULE, N, granted} ->
+ ?ets_insert(Store, {sticky, true}),
?ets_insert(Store, {{locks, Tab, Key}, write}),
[?ets_insert(Store, {nodes, Node}) || Node <- WNodes],
granted;
{?MODULE, N, {granted, Val}} -> %% for rwlocks
+ ?ets_insert(Store, {sticky, true}),
case opt_lookup_in_client(Val, Oid, write) of
C = #cyclic{} ->
exit({aborted, C});
diff --git a/lib/mnesia/src/mnesia_tm.erl b/lib/mnesia/src/mnesia_tm.erl
index 8b79fca1d7..1fa920321b 100644
--- a/lib/mnesia/src/mnesia_tm.erl
+++ b/lib/mnesia/src/mnesia_tm.erl
@@ -26,7 +26,7 @@
init/1,
non_transaction/5,
transaction/6,
- commit_participant/5,
+ commit_participant/6,
dirty/2,
display_info/2,
do_update_op/3,
@@ -62,13 +62,14 @@
%% Format on coordinators is [{Tid, EtsTabList} .....
-record(prep, {protocol = sym_trans,
- %% async_dirty | sync_dirty | sym_trans | sync_sym_trans | asym_trans
+ %% async_dirty | sync_dirty | sym_trans | sync_sym_trans | asym_trans | sync_asym_trans
records = [],
prev_tab = [], % initiate to a non valid table name
prev_types,
prev_snmp,
types,
- majority = []
+ majority = [],
+ sync = false
}).
-record(participant, {tid, pid, commit, disc_nodes = [],
@@ -250,11 +251,13 @@ doit_loop(#state{coordinators=Coordinators,participants=Participants,supervisor=
mnesia_checkpoint:tm_enter_pending(Tid, DiscNs, RamNs),
Commit = new_cr_format(Commit0),
Pid =
- case Protocol of
- asym_trans when node(Tid#tid.pid) /= node() ->
- Args = [tmpid(From), Tid, Commit, DiscNs, RamNs],
+ if
+ node(Tid#tid.pid) =:= node() ->
+ error({internal_error, local_node});
+ Protocol =:= asym_trans orelse Protocol =:= sync_asym_trans ->
+ Args = [Protocol, tmpid(From), Tid, Commit, DiscNs, RamNs],
spawn_link(?MODULE, commit_participant, Args);
- _ when node(Tid#tid.pid) /= node() -> %% *_sym_trans
+ true -> %% *_sym_trans
reply(From, {vote_yes, Tid}),
nopid
end,
@@ -1190,7 +1193,15 @@ do_arrange(Tid, Store, RestoreKey, Prep, N) when RestoreKey == restore_op ->
P2 = Prep#prep{protocol = asym_trans, records = Recs2},
do_arrange(Tid, Store, ?ets_next(Store, RestoreKey), P2, N + 1);
do_arrange(_Tid, _Store, '$end_of_table', Prep, N) ->
- {N, Prep};
+ case Prep of
+ #prep{sync=true, protocol=asym_trans} ->
+ {N, Prep#prep{protocol=sync_asym_trans}};
+ _ ->
+ {N, Prep}
+ end;
+do_arrange(Tid, Store, sticky, Prep, N) ->
+ P2 = Prep#prep{sync=true},
+ do_arrange(Tid, Store, ?ets_next(Store, sticky), P2, N);
do_arrange(Tid, Store, IgnoredKey, Prep, N) -> %% locks, nodes ... local atoms...
do_arrange(Tid, Store, ?ets_next(Store, IgnoredKey), Prep, N).
@@ -1448,7 +1459,8 @@ multi_commit(sync_sym_trans, _Maj = [], Tid, CR, Store) ->
[{tid, Tid}, {outcome, Outcome}]),
Outcome;
-multi_commit(asym_trans, Majority, Tid, CR, Store) ->
+multi_commit(Protocol, Majority, Tid, CR, Store)
+ when Protocol =:= asym_trans; Protocol =:= sync_asym_trans ->
%% This more expensive commit protocol is used when
%% table definitions are changed (schema transactions).
%% It is also used when the involved tables are
@@ -1515,7 +1527,7 @@ multi_commit(asym_trans, Majority, Tid, CR, Store) ->
end,
Pending = mnesia_checkpoint:tm_enter_pending(Tid, DiscNs, RamNs),
?ets_insert(Store, Pending),
- {WaitFor, Local} = ask_commit(asym_trans, Tid, CR2, DiscNs, RamNs),
+ {WaitFor, Local} = ask_commit(Protocol, Tid, CR2, DiscNs, RamNs),
SchemaPrep = ?CATCH(mnesia_schema:prepare_commit(Tid, Local, {coord, WaitFor})),
{Votes, Pids} = rec_all(WaitFor, Tid, do_commit, []),
@@ -1563,38 +1575,38 @@ multi_commit(asym_trans, Majority, Tid, CR, Store) ->
%% Returns do_commit or {do_abort, Reason}
rec_acc_pre_commit([Pid | Tail], Tid, Store, Commit, Res, DumperMode,
- GoodPids, SchemaAckPids) ->
+ GoodPids, AckPids) ->
receive
{?MODULE, _, {acc_pre_commit, Tid, Pid, true}} ->
rec_acc_pre_commit(Tail, Tid, Store, Commit, Res, DumperMode,
- [Pid | GoodPids], [Pid | SchemaAckPids]);
+ [Pid | GoodPids], [Pid | AckPids]);
{?MODULE, _, {acc_pre_commit, Tid, Pid, false}} ->
rec_acc_pre_commit(Tail, Tid, Store, Commit, Res, DumperMode,
- [Pid | GoodPids], SchemaAckPids);
+ [Pid | GoodPids], AckPids);
{?MODULE, _, {acc_pre_commit, Tid, Pid}} ->
%% Kept for backwards compatibility. Remove after Mnesia 4.x
rec_acc_pre_commit(Tail, Tid, Store, Commit, Res, DumperMode,
- [Pid | GoodPids], [Pid | SchemaAckPids]);
+ [Pid | GoodPids], [Pid | AckPids]);
{?MODULE, _, {do_abort, Tid, Pid, _Reason}} ->
AbortRes = {do_abort, {bad_commit, node(Pid)}},
rec_acc_pre_commit(Tail, Tid, Store, Commit, AbortRes, DumperMode,
- GoodPids, SchemaAckPids);
+ GoodPids, AckPids);
{mnesia_down, Node} when Node == node(Pid) ->
AbortRes = {do_abort, {bad_commit, Node}},
?SAFE(Pid ! {Tid, AbortRes}), %% Tell him that he has died
rec_acc_pre_commit(Tail, Tid, Store, Commit, AbortRes, DumperMode,
- GoodPids, SchemaAckPids)
+ GoodPids, AckPids)
end;
-rec_acc_pre_commit([], Tid, Store, {Commit,OrigC}, Res, DumperMode, GoodPids, SchemaAckPids) ->
+rec_acc_pre_commit([], Tid, Store, {Commit,OrigC}, Res, DumperMode, GoodPids, AckPids) ->
D = Commit#commit.decision,
case Res of
do_commit ->
%% Now everybody knows that the others
%% has voted yes. We also know that
%% everybody are uncertain.
- prepare_sync_schema_commit(Store, SchemaAckPids),
+ prepare_sync_schema_commit(Store, AckPids),
tell_participants(GoodPids, {Tid, committed}),
D2 = D#decision{outcome = committed},
mnesia_recover:log_decision(D2),
@@ -1606,7 +1618,7 @@ rec_acc_pre_commit([], Tid, Store, {Commit,OrigC}, Res, DumperMode, GoodPids, Sc
do_commit(Tid, Commit, DumperMode),
?eval_debug_fun({?MODULE, rec_acc_pre_commit_done_commit},
[{tid, Tid}]),
- sync_schema_commit(Tid, Store, SchemaAckPids),
+ sync_schema_commit(Tid, Store, AckPids),
mnesia_locker:release_tid(Tid),
?MODULE ! {delete_transaction, Tid};
@@ -1623,6 +1635,7 @@ rec_acc_pre_commit([], Tid, Store, {Commit,OrigC}, Res, DumperMode, GoodPids, Sc
Res.
%% Note all nodes in case of mnesia_down mgt
+%% sync_schema_commit is (ab)used for sync_asym_trans as well.
prepare_sync_schema_commit(_Store, []) ->
ok;
prepare_sync_schema_commit(Store, [Pid | Pids]) ->
@@ -1648,17 +1661,17 @@ tell_participants([Pid | Pids], Msg) ->
tell_participants([], _Msg) ->
ok.
--spec commit_participant(_, _, _, _, _) -> no_return().
+-spec commit_participant(_, _, _, _, _, _) -> no_return().
%% Trap exit because we can get a shutdown from application manager
-commit_participant(Coord, Tid, Bin, DiscNs, RamNs) when is_binary(Bin) ->
+commit_participant(Protocol, Coord, Tid, Bin, DiscNs, RamNs) when is_binary(Bin) ->
process_flag(trap_exit, true),
Commit = binary_to_term(Bin),
- commit_participant(Coord, Tid, Bin, Commit, DiscNs, RamNs);
-commit_participant(Coord, Tid, C = #commit{}, DiscNs, RamNs) ->
+ commit_participant(Protocol, Coord, Tid, Bin, Commit, DiscNs, RamNs);
+commit_participant(Protocol, Coord, Tid, C = #commit{}, DiscNs, RamNs) ->
process_flag(trap_exit, true),
- commit_participant(Coord, Tid, C, C, DiscNs, RamNs).
+ commit_participant(Protocol, Coord, Tid, C, C, DiscNs, RamNs).
-commit_participant(Coord, Tid, Bin, C0, DiscNs, _RamNs) ->
+commit_participant(Protocol, Coord, Tid, Bin, C0, DiscNs, _RamNs) ->
?eval_debug_fun({?MODULE, commit_participant, pre}, [{tid, Tid}]),
try mnesia_schema:prepare_commit(Tid, C0, {part, Coord}) of
{Modified, C = #commit{}, DumperMode} ->
@@ -1683,8 +1696,9 @@ commit_participant(Coord, Tid, Bin, C0, DiscNs, _RamNs) ->
mnesia_recover:log_decision(D#decision{outcome = unclear}),
?eval_debug_fun({?MODULE, commit_participant, pre_commit},
[{tid, Tid}]),
- Expect_schema_ack = C#commit.schema_ops /= [],
- reply(Coord, {acc_pre_commit, Tid, self(), Expect_schema_ack}),
+ ExpectAck = C#commit.schema_ops /= []
+ orelse Protocol =:= sync_asym_trans,
+ reply(Coord, {acc_pre_commit, Tid, self(), ExpectAck}),
%% Now we are vulnerable for failures, since
%% we cannot decide without asking others
@@ -1694,7 +1708,7 @@ commit_participant(Coord, Tid, Bin, C0, DiscNs, _RamNs) ->
?eval_debug_fun({?MODULE, commit_participant, log_commit},
[{tid, Tid}]),
do_commit(Tid, C, DumperMode),
- case Expect_schema_ack of
+ case ExpectAck of
false -> ignore;
true -> reply(Coord, {schema_commit, Tid, self()})
end,
@@ -2304,7 +2318,7 @@ reconfigure_participants(_, []) ->
%% tell mnesia_tm on all involved nodes (including the local node)
%% about the outcome.
tell_outcome(Tid, Protocol, Node, CheckNodes, TellNodes) ->
- Outcome = mnesia_recover:what_happened(Tid, Protocol, CheckNodes),
+ Outcome = mnesia_recover:what_happened(Tid, proto(Protocol), CheckNodes),
case Outcome of
aborted ->
rpc:abcast(TellNodes, ?MODULE, {Tid,{do_abort, {mnesia_down, Node}}});
@@ -2313,6 +2327,9 @@ tell_outcome(Tid, Protocol, Node, CheckNodes, TellNodes) ->
end,
Outcome.
+proto(sync_asym_trans) -> asym_trans;
+proto(Proto) -> Proto.
+
do_stop(#state{coordinators = Coordinators}) ->
Msg = {mnesia_down, node()},
lists:foreach(fun({Tid, _}) -> Tid#tid.pid ! Msg end, gb_trees:to_list(Coordinators)),
diff --git a/lib/mnesia/test/mt b/lib/mnesia/test/mt
index a398ee0422..b169734f56 100755
--- a/lib/mnesia/test/mt
+++ b/lib/mnesia/test/mt
@@ -34,8 +34,35 @@ erlcmd="erl -sname a $p $args -mnesia_test_timeout"
erlcmd1="erl -sname a1 $p $args"
erlcmd2="erl -sname a2 $p $args"
-xterm -geometry 70x20+0+550 -T a1 -e $erlcmd1 &
-xterm -geometry 70x20+450+550 -T a2 -e $erlcmd2 &
+if test z"$MT_TERM" = z ; then
+ MT_TERM=xterm
+fi
+
+case $MT_TERM in
+ xterm)
+ geom0="-geometry 142x40+0+0"
+ geom1="-geometry 70x20+0+550"
+ geom2="-geometry 70x20+480+550"
+ title="-T"
+ exec="-e"
+ ;;
+ gnome-terminal)
+ geom0="--geometry 142x40+0+0"
+ geom1="--geometry 70x20+0+740"
+ geom2="--geometry 70x20+700+740"
+ title="--title"
+ exec="--hide-menubar --"
+ ;;
+ *rxvt)
+ geom0="-geometry 142x40+0+0"
+ geom1="-geometry 70x20+0+680"
+ geom2="-geometry 70x20+630+680"
+ title="-title"
+ exec="-e"
+esac
+
+$MT_TERM $geom1 $title a1 $exec $erlcmd1 &
+$MT_TERM $geom2 $title a2 $exec $erlcmd2 &
rm "$latest" 2>/dev/null
ln -s "$log" "$latest"
@@ -51,11 +78,6 @@ echo "Give the following command in order to see the outcome from node a@$h"":"
echo ""
echo " less test_log$$"
-ostype=`uname -s`
-if [ "$ostype" = "SunOS" ] ; then
- /usr/openwin/bin/xterm -geometry 145x40+0+0 -T a -l -lf "$log" -e $erlcmd &
-else
- xterm -geometry 145x40+0+0 -T a -e script -f -c "$erlcmd" "$log" &
-fi
+$MT_TERM $geom0 $title a $exec script -f -c "$erlcmd" "$log" &
tail -f "$log" | egrep 'Eval|<>ERROR|NYI'
--
2.16.4
