aboutsummaryrefslogtreecommitdiffstats
path: root/lib/mnesia
diff options
context:
space:
mode:
Diffstat (limited to 'lib/mnesia')
-rw-r--r--lib/mnesia/src/mnesia_schema.erl82
-rw-r--r--lib/mnesia/test/mnesia_isolation_test.erl71
2 files changed, 77 insertions, 76 deletions
diff --git a/lib/mnesia/src/mnesia_schema.erl b/lib/mnesia/src/mnesia_schema.erl
index 593360415d..2acddccf6e 100644
--- a/lib/mnesia/src/mnesia_schema.erl
+++ b/lib/mnesia/src/mnesia_schema.erl
@@ -1297,6 +1297,7 @@ make_del_table_copy(Tab, Node) ->
_ ->
ensure_active(Cs),
verify_cstruct(Cs2),
+ get_tid_ts_and_lock(Tab, write),
[{op, del_table_copy, Storage, Node, vsn_cs2list(Cs2)}]
end.
@@ -1324,6 +1325,7 @@ remove_node_from_tabs([Tab|Rest], Node) ->
remove_node_from_tabs(Rest, Node)];
_Ns ->
verify_cstruct(Cs2),
+ get_tid_ts_and_lock(Tab, write),
[{op, del_table_copy, ram_copies, Node, vsn_cs2list(Cs2)}|
remove_node_from_tabs(Rest, Node)]
end
@@ -1355,6 +1357,7 @@ do_move_table(schema, _FromNode, _ToNode) ->
mnesia:abort({bad_type, schema});
do_move_table(Tab, FromNode, ToNode) when is_atom(FromNode), is_atom(ToNode) ->
TidTs = get_tid_ts_and_lock(schema, write),
+ %% get_tid_ts_and_lock(Tab, write), write locked by load_table in mnesia_loader
insert_schema_ops(TidTs, make_move_table(Tab, FromNode, ToNode));
do_move_table(Tab, FromNode, ToNode) ->
mnesia:abort({badarg, Tab, FromNode, ToNode}).
@@ -1993,28 +1996,11 @@ prepare_op(Tid, {op, add_table_copy, Storage, Node, TabDef}, _WaitFor) ->
{true, optional}
end;
-prepare_op(Tid, {op, del_table_copy, _Storage, Node, TabDef}, _WaitFor) ->
+prepare_op(_Tid, {op, del_table_copy, _Storage, Node, TabDef}, _WaitFor) ->
Cs = list2cs(TabDef),
Tab = Cs#cstruct.name,
-
- if
- %% Schema table lock is always required to run a schema op.
- %% No need to look it.
- node(Tid#tid.pid) == node(), Tab /= schema ->
- Self = self(),
- Pid = spawn_link(fun() -> lock_del_table(Tab, Node, Cs, Self) end),
- put(mnesia_lock, Pid),
- receive
- {Pid, updated} ->
- {true, optional};
- {Pid, FailReason} ->
- mnesia:abort(FailReason);
- {'EXIT', Pid, Reason} ->
- mnesia:abort(Reason)
- end;
- true ->
- {true, optional}
- end;
+ set_where_to_read(Tab, Node, Cs),
+ {true, optional};
prepare_op(_Tid, {op, change_table_copy_type, N, FromS, ToS, TabDef}, _WaitFor)
when N == node() ->
@@ -2228,46 +2214,6 @@ receive_sync(Nodes, Pids) ->
{abort, Else}
end.
-lock_del_table(Tab, NewNode, Cs0, Father) ->
- Ns = val({schema, active_replicas}),
- process_flag(trap_exit,true),
- Lock = fun() ->
- mnesia:write_lock_table(Tab),
- %% Sigh using cs record
- Set = fun(Node) ->
- [Cs] = normalize_cs([Cs0], Node),
- rpc:call(Node, ?MODULE, set_where_to_read, [Tab, NewNode, Cs])
- end,
- Res = [Set(Node) || Node <- Ns],
- Filter = fun(ok) ->
- false;
- ({badrpc, {'EXIT', {undef, _}}}) ->
- %% This will be the case we talks with elder nodes
- %% than 3.8.2, they will set where_to_read without
- %% getting a lock.
- false;
- (_) ->
- true
- end,
- case lists:filter(Filter, Res) of
- [] ->
- Father ! {self(), updated},
- %% When transaction is commited the process dies
- %% and the lock is released.
- receive _ -> ok end;
- Err ->
- Father ! {self(), {bad_commit, Err}}
- end,
- ok
- end,
- case mnesia:transaction(Lock) of
- {atomic, ok} -> ok;
- {aborted, R} -> Father ! {self(), R}
- end,
- unlink(Father),
- unlink(whereis(mnesia_tm)),
- exit(normal).
-
set_where_to_read(Tab, Node, Cs) ->
case mnesia_lib:val({Tab, where_to_read}) of
Node ->
@@ -2418,13 +2364,19 @@ undo_prepare_op(Tid, {op, add_table_copy, Storage, Node, TabDef}) ->
insert_cstruct(Tid, Cs2, true) % Don't care about the version
end;
-undo_prepare_op(_Tid, {op, del_table_copy, _, Node, TabDef})
- when Node == node() ->
- WriteLocker = get(mnesia_lock),
- WriteLocker =/= undefined andalso (WriteLocker ! die),
+undo_prepare_op(_Tid, {op, del_table_copy, _, Node, TabDef}) ->
Cs = list2cs(TabDef),
Tab = Cs#cstruct.name,
- mnesia_lib:set({Tab, where_to_read}, Node);
+ if node() =:= Node ->
+ mnesia_lib:set({Tab, where_to_read}, Node);
+ true ->
+ case mnesia_lib:val({Tab, where_to_read}) of
+ nowhere ->
+ mnesia_lib:set_remote_where_to_read(Tab);
+ true ->
+ ignore
+ end
+ end;
undo_prepare_op(_Tid, {op, change_table_copy_type, N, FromS, ToS, TabDef})
when N == node() ->
diff --git a/lib/mnesia/test/mnesia_isolation_test.erl b/lib/mnesia/test/mnesia_isolation_test.erl
index b66da6e390..4dd0c01d05 100644
--- a/lib/mnesia/test/mnesia_isolation_test.erl
+++ b/lib/mnesia/test/mnesia_isolation_test.erl
@@ -39,7 +39,7 @@ groups() ->
[{locking, [],
[no_conflict, simple_queue_conflict,
advanced_queue_conflict, simple_deadlock_conflict,
- advanced_deadlock_conflict, lock_burst,
+ advanced_deadlock_conflict, schema_deadlock, lock_burst,
{group, sticky_locks}, {group, unbound_locking},
{group, admin_conflict}, nasty]},
{sticky_locks, [], [basic_sticky_functionality]},
@@ -148,20 +148,32 @@ simple_queue_conflict(Config) when is_list(Config) ->
fun_loop(Fun, AllSharedLocks, OneExclusiveLocks),
ok.
-wait_for_lock(Pid, _Nodes, 0) ->
+wait_for_lock(Pid, Nodes, Retry) ->
+ wait_for_lock(Pid, Nodes, Retry, queue).
+
+wait_for_lock(Pid, _Nodes, 0, queue) ->
Queue = mnesia:system_info(lock_queue),
?error("Timeout while waiting for lock on Pid ~p in queue ~p~n", [Pid, Queue]);
-wait_for_lock(Pid, Nodes, N) ->
- rpc:multicall(Nodes, sys, get_status, [mnesia_locker]),
- List = [rpc:call(Node, mnesia, system_info, [lock_queue]) || Node <- Nodes],
+wait_for_lock(Pid, _Nodes, 0, held) ->
+ Held = mnesia:system_info(held_locks),
+ ?error("Timeout while waiting for lock on Pid ~p (held) ~p~n", [Pid, Held]);
+wait_for_lock(Pid, Nodes, N, Where) ->
+ rpc:multicall(Nodes, sys, get_status, [mnesia_locker]),
+ List = case Where of
+ queue ->
+ [rpc:call(Node, mnesia, system_info, [lock_queue]) || Node <- Nodes];
+ held ->
+ [rpc:call(Node, mnesia, system_info, [held_locks]) || Node <- Nodes]
+ end,
Q = lists:append(List),
- check_q(Pid, Q, Nodes, N).
+ check_q(Pid, Q, Nodes, N, Where).
-check_q(Pid, [{_Oid, _Op, Pid, _Tid, _WFT} | _Tail], _N, _Count) -> ok;
-check_q(Pid, [_ | Tail], N, Count) -> check_q(Pid, Tail, N, Count);
-check_q(Pid, [], N, Count) ->
- timer:sleep(500),
- wait_for_lock(Pid, N, Count - 1).
+check_q(Pid, [{_Oid, _Op, Pid, _Tid, _WFT} | _Tail], _N, _Count, _Where) -> ok;
+check_q(Pid, [{_Oid, _Op, {tid,_,Pid}} | _Tail], _N, _Count, _Where) -> ok;
+check_q(Pid, [_ | Tail], N, Count, Where) -> check_q(Pid, Tail, N, Count, Where);
+check_q(Pid, [], N, Count, Where) ->
+ timer:sleep(200),
+ wait_for_lock(Pid, N, Count - 1, Where).
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@@ -270,6 +282,43 @@ advanced_deadlock_conflict(Config) when is_list(Config) ->
?match([], mnesia:system_info(lock_queue)),
ok.
+%% Verify (and regression test) deadlock in del_table_copy(schema, Node)
+schema_deadlock(Config) when is_list(Config) ->
+ Ns = [Node1, Node2] = ?acquire_nodes(2, Config),
+ ?match({atomic, ok}, mnesia:create_table(a, [{disc_copies, Ns}])),
+ ?match({atomic, ok}, mnesia:create_table(b, [{disc_copies, Ns}])),
+
+ Tester = self(),
+
+ Deadlocker = fun() ->
+ mnesia:write({a,1,1}), %% grab write lock on A
+ receive
+ continue ->
+ mnesia:write({b,1,1}), %% grab write lock on B
+ end_trans
+ end
+ end,
+
+ ?match(stopped, rpc:call(Node2, mnesia, stop, [])),
+ timer:sleep(500), %% Let Node1 reconfigure
+ sys:get_status(mnesia_monitor),
+
+ DoingTrans = spawn_link(fun() -> Tester ! {self(),mnesia:transaction(Deadlocker)} end),
+ wait_for_lock(DoingTrans, [Node1], 10, held),
+ %% Will grab write locks on schema, a, and b
+ DoingSchema = spawn_link(fun() -> Tester ! {self(), mnesia:del_table_copy(schema, Node2)} end),
+ timer:sleep(500), %% Let schema trans start, and try to grab locks
+ DoingTrans ! continue,
+
+ ?match(ok, receive {DoingTrans, {atomic, end_trans}} -> ok after 5000 -> timeout end),
+ ?match(ok, receive {DoingSchema, {atomic, ok}} -> ok after 5000 -> timeout end),
+
+ sys:get_status(whereis(mnesia_locker)), % Explicit sync, release locks is async
+ ?match([], mnesia:system_info(held_locks)),
+ ?match([], mnesia:system_info(lock_queue)),
+ ok.
+
+
one_oid(Tab) -> {Tab, 1}.
other_oid(Tab) -> {Tab, 2}.
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-03 01:46:38 +0000