aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--lib/mnesia/src/mnesia_locker.erl74
1 files changed, 36 insertions, 38 deletions
diff --git a/lib/mnesia/src/mnesia_locker.erl b/lib/mnesia/src/mnesia_locker.erl
index de4811f8e4..6e21332480 100644
--- a/lib/mnesia/src/mnesia_locker.erl
+++ b/lib/mnesia/src/mnesia_locker.erl
@@ -1,7 +1,7 @@
%%
%% %CopyrightBegin%
%%
-%% Copyright Ericsson AB 1996-2011. All Rights Reserved.
+%% Copyright Ericsson AB 1996-2012. All Rights Reserved.
%%
%% The contents of this file are subject to the Erlang Public License,
%% Version 1.1, (the "License"); you may not use this file except in
@@ -66,8 +66,8 @@
-record(queue, {oid, tid, op, pid, lucky}).
-%% mnesia_held_locks: contain {Oid, Op, Tid} entries (bag)
--define(match_oid_held_locks(Oid), {Oid, '_', '_'}).
+%% mnesia_held_locks: contain {{Oid,Tid}, Op} entries
+-define(match_oid_held_locks(Oid), {{Oid, '_'}, '_'}).
%% mnesia_tid_locks: contain {Tid, Oid, Op} entries (bag)
-define(match_oid_tid_locks(Tid), {Tid, '_', '_'}).
%% mnesia_sticky_locks: contain {Oid, Node} entries and {Tab, Node} entries (set)
@@ -83,7 +83,7 @@ start() ->
init(Parent) ->
register(?MODULE, self()),
process_flag(trap_exit, true),
- ?ets_new_table(mnesia_held_locks, [bag, private, named_table]),
+ ?ets_new_table(mnesia_held_locks, [ordered_set, private, named_table]),
?ets_new_table(mnesia_tid_locks, [bag, private, named_table]),
?ets_new_table(mnesia_sticky_locks, [set, private, named_table]),
?ets_new_table(mnesia_lock_queue, [bag, private, named_table, {keypos, 2}]),
@@ -237,7 +237,7 @@ loop(State) ->
set_lock(Tid, Oid, Op) ->
?dbg("Granted ~p ~p ~p~n", [Tid,Oid,Op]),
- ?ets_insert(mnesia_held_locks, {Oid, Op, Tid}),
+ ?ets_insert(mnesia_held_locks, {{Oid, Tid}, Op}),
?ets_insert(mnesia_tid_locks, {Tid, Oid, Op}).
%%%%%%%%%%%%%%%%%%%%%%%%%%%
@@ -321,19 +321,19 @@ grant_lock(Tid, write, Lock, Oid) ->
can_lock(Tid, read, {Tab, Key}, AlreadyQ) when Key /= ?ALL ->
%% The key is bound, no need for the other BIF
Oid = {Tab, Key},
- ObjLocks = ?ets_match_object(mnesia_held_locks, {Oid, write, '_'}),
- TabLocks = ?ets_match_object(mnesia_held_locks, {{Tab, ?ALL}, write, '_'}),
+ ObjLocks = ?ets_match_object(mnesia_held_locks, {{Oid, '_'}, write}),
+ TabLocks = ?ets_match_object(mnesia_held_locks, {{{Tab, ?ALL}, '_'}, write}),
check_lock(Tid, Oid, ObjLocks, TabLocks, yes, AlreadyQ, read);
can_lock(Tid, read, Oid, AlreadyQ) -> % Whole tab
Tab = element(1, Oid),
- ObjLocks = ?ets_match_object(mnesia_held_locks, {{Tab, '_'}, write, '_'}),
+ ObjLocks = ?ets_match_object(mnesia_held_locks, {{{Tab, '_'}, '_'}, write}),
check_lock(Tid, Oid, ObjLocks, [], yes, AlreadyQ, read);
can_lock(Tid, write, {Tab, Key}, AlreadyQ) when Key /= ?ALL ->
Oid = {Tab, Key},
- ObjLocks = ?ets_lookup(mnesia_held_locks, Oid),
- TabLocks = ?ets_lookup(mnesia_held_locks, {Tab, ?ALL}),
+ ObjLocks = ?ets_match_object(mnesia_held_locks, ?match_oid_held_locks(Oid)),
+ TabLocks = ?ets_match_object(mnesia_held_locks, ?match_oid_held_locks({Tab, ?ALL})),
check_lock(Tid, Oid, ObjLocks, TabLocks, yes, AlreadyQ, write);
can_lock(Tid, write, Oid, AlreadyQ) -> % Whole tab
@@ -342,31 +342,28 @@ can_lock(Tid, write, Oid, AlreadyQ) -> % Whole tab
check_lock(Tid, Oid, ObjLocks, [], yes, AlreadyQ, write).
%% Check held locks for conflicting locks
-check_lock(Tid, Oid, [Lock | Locks], TabLocks, X, AlreadyQ, Type) ->
- case element(3, Lock) of
- Tid ->
- check_lock(Tid, Oid, Locks, TabLocks, X, AlreadyQ, Type);
- WaitForTid ->
- Queue = allowed_to_be_queued(WaitForTid,Tid),
- if Queue == true ->
- check_lock(Tid, Oid, Locks, TabLocks, {queue, WaitForTid}, AlreadyQ, Type);
- Tid#tid.pid == WaitForTid#tid.pid ->
- dbg_out("Spurious lock conflict ~w ~w: ~w -> ~w~n",
- [Oid, Lock, Tid, WaitForTid]),
- %% Test..
- {Tab, _Key} = Oid,
- HaveQ = (ets:lookup(mnesia_lock_queue, Oid) /= [])
- orelse (ets:lookup(mnesia_lock_queue,{Tab,?ALL}) /= []),
- if
- HaveQ ->
- {no, WaitForTid};
- true ->
- check_lock(Tid,Oid,Locks,TabLocks,{queue,WaitForTid},AlreadyQ,Type)
- end;
- %%{no, WaitForTid}; Safe solution
- true ->
- {no, WaitForTid}
- end
+check_lock(Tid, Oid, [{{_,Tid}, _} | Locks], TabLocks, X, AlreadyQ, Type) ->
+ check_lock(Tid, Oid, Locks, TabLocks, X, AlreadyQ, Type);
+check_lock(Tid, Oid, [Lock = {{_,WaitForTid}, _} | Locks], TabLocks, _X, AlreadyQ, Type) ->
+ Queue = allowed_to_be_queued(WaitForTid,Tid),
+ if Queue == true ->
+ check_lock(Tid, Oid, Locks, TabLocks, {queue, WaitForTid}, AlreadyQ, Type);
+ Tid#tid.pid == WaitForTid#tid.pid ->
+ dbg_out("Spurious lock conflict ~w ~w: ~w -> ~w~n",
+ [Oid, Lock, Tid, WaitForTid]),
+ %% Test..
+ {Tab, _Key} = Oid,
+ HaveQ = (ets:lookup(mnesia_lock_queue, Oid) /= [])
+ orelse (ets:lookup(mnesia_lock_queue,{Tab,?ALL}) /= []),
+ if
+ HaveQ ->
+ {no, WaitForTid};
+ true ->
+ check_lock(Tid,Oid,Locks,TabLocks,{queue,WaitForTid},AlreadyQ,Type)
+ end;
+ %%{no, WaitForTid}; Safe solution
+ true ->
+ {no, WaitForTid}
end;
check_lock(_, _, [], [], X, {queue, bad_luck}, _) ->
@@ -523,9 +520,9 @@ release_lock({Tid, Oid, {queued, _}}) ->
release_lock({Tid, Oid, Op}) ->
if
Op == write ->
- ?ets_delete(mnesia_held_locks, Oid);
+ ?ets_delete(mnesia_held_locks, {Oid, Tid});
Op == read ->
- ets:delete_object(mnesia_held_locks, {Oid, Op, Tid})
+ ets:delete_object(mnesia_held_locks, {{Oid, Tid}, Op})
end.
rearrange_queue([{_Tid, {Tab, Key}, _} | Locks]) ->
@@ -1116,7 +1113,8 @@ rec_requests([], _Oid, _Store) ->
get_held_locks() ->
?MODULE ! {get_table, self(), mnesia_held_locks},
- receive {mnesia_held_locks, Locks} -> Locks end.
+ Locks = receive {mnesia_held_locks, Ls} -> Ls end,
+ [{Oid, Op, Tid} || {{Oid, Tid}, Op} <- Locks].
get_lock_queue() ->
?MODULE ! {get_table, self(), mnesia_lock_queue},