Merge branch 'dgud/mnesia/read-sticky-bug/OTP-9786'

* dgud/mnesia/read-sticky-bug/OTP-9786:
  [mnesia] Read record from correct node
  [mnesia] Fixed sticky read lock bug
  [mnesia] Whitespace fixes

Conflicts:
	lib/mnesia/src/mnesia_log.erl

1 files changed, 99 insertions, 118 deletions

diff --git a/lib/mnesia/src/mnesia_locker.erl b/lib/mnesia/src/mnesia_locker.erl
index 0492d794f3..de4811f8e4 100644
--- a/lib/mnesia/src/mnesia_locker.erl
+++ b/lib/mnesia/src/mnesia_locker.erl
@@ -1,19 +1,19 @@
 %%
 %% %CopyrightBegin%
-%% 
+%%
 %% Copyright Ericsson AB 1996-2011. 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
 %% compliance with the License. You should have received a copy of the
 %% Erlang Public License along with this software. If not, it can be
 %% retrieved online at http://www.erlang.org/.
-%% 
+%%
 %% Software distributed under the License is distributed on an "AS IS"
 %% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
 %% the License for the specific language governing rights and limitations
 %% under the License.
-%% 
+%%
 %% %CopyrightEnd%
 %%
 
@@ -68,12 +68,12 @@
 
 %% mnesia_held_locks: contain       {Oid, Op, Tid} entries  (bag)
 -define(match_oid_held_locks(Oid),  {Oid, '_', '_'}).
-%% mnesia_tid_locks: contain        {Tid, Oid, Op} entries  (bag) 
+%% 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)
 -define(match_oid_sticky_locks(Oid),{Oid, '_'}).
 %% mnesia_lock_queue: contain       {queue, Oid, Tid, Op, ReplyTo, WaitForTid} entries (bag)
--define(match_oid_lock_queue(Oid),  #queue{oid=Oid, tid='_', op = '_', pid = '_', lucky = '_'}). 
+-define(match_oid_lock_queue(Oid),  #queue{oid=Oid, tid='_', op = '_', pid = '_', lucky = '_'}).
 %% mnesia_lock_counter:             {{write, Tab}, Number} &&
 %%                                  {{read, Tab}, Number} entries  (set)
 
@@ -83,11 +83,11 @@ 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, [bag, 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}]),
-    
+
     proc_lib:init_ack(Parent, {ok, self()}),
     case ?catch_val(pid_sort_order) of
 	r9b_plain -> put(pid_sort_order, r9b_plain);
@@ -98,8 +98,8 @@ init(Parent) ->
 
 val(Var) ->
     case ?catch_val(Var) of
-	{'EXIT', _ReASoN_} -> mnesia_lib:other_val(Var, _ReASoN_); 
-	_VaLuE_ -> _VaLuE_ 
+	{'EXIT', _ReASoN_} -> mnesia_lib:other_val(Var, _ReASoN_);
+	_VaLuE_ -> _VaLuE_
     end.
 
 reply(From, R) ->
@@ -111,10 +111,10 @@ l_request(Node, X, Store) ->
 
 l_req_rec(Node, Store) ->
     ?ets_insert(Store, {nodes, Node}),
-    receive 
-	{?MODULE, Node, Reply} -> 
+    receive
+	{?MODULE, Node, Reply} ->
 	    Reply;
-	{mnesia_down, Node} -> 
+	{mnesia_down, Node} ->
 	    {not_granted, {node_not_running, Node}}
     end.
 
@@ -128,10 +128,10 @@ send_release_tid(Nodes, Tid) ->
     rpc:abcast(Nodes, ?MODULE, {self(), {sync_release_tid, Tid}}).
 
 receive_release_tid_acc([Node | Nodes], Tid) ->
-    receive 
-	{?MODULE, Node, {tid_released, Tid}} -> 
+    receive
+	{?MODULE, Node, {tid_released, Tid}} ->
 	    receive_release_tid_acc(Nodes, Tid);
-	{mnesia_down, Node} -> 
+	{mnesia_down, Node} ->
 	    receive_release_tid_acc(Nodes, Tid)
     end;
 receive_release_tid_acc([], _Tid) ->
@@ -152,27 +152,27 @@ loop(State) ->
 
 	%% Really do a  read, but get hold of a write lock
 	%% used by mnesia:wread(Oid).
-	
+
 	{From, {read_write, Tid, Oid}} ->
 	    try_sticky_lock(Tid, read_write, From, Oid),
 	    loop(State);
-	
+
 	%% Tid has somehow terminated, clear up everything
 	%% and pass locks on to queued processes.
 	%% This is the purpose of the mnesia_tid_locks table
-	
+
 	{release_tid, Tid} ->
 	    do_release_tid(Tid),
 	    loop(State);
-	
+
 	%% stick lock, first tries this to the where_to_read Node
 	{From, {test_set_sticky, Tid, {Tab, _} = Oid, Lock}} ->
 	    case ?ets_lookup(mnesia_sticky_locks, Tab) of
-		[] -> 
+		[] ->
 		    reply(From, not_stuck),
 		    loop(State);
 		[{_,Node}] when Node == node() ->
-		    %% Lock is stuck here, see now if we can just set 
+		    %% Lock is stuck here, see now if we can just set
 		    %% a regular write lock
 		    try_lock(Tid, Lock, From, Oid),
 		    loop(State);
@@ -188,7 +188,7 @@ loop(State) ->
 	    ?ets_insert(mnesia_sticky_locks, {Tab, N}),
 	    loop(State);
 
-	%% The caller which sends this message, must have first 
+	%% The caller which sends this message, must have first
 	%% aquired a write lock on the entire table
 	{unstick, Tab} ->
 	    ?ets_delete(mnesia_sticky_locks, Tab),
@@ -205,14 +205,14 @@ loop(State) ->
 		[{_,N}] ->
 		    Req = {From, {ix_read, Tid, Tab, IxKey, Pos}},
 		    From ! {?MODULE, node(), {switch, N, Req}},
-		    loop(State)	   
+		    loop(State)
 	    end;
 
 	{From, {sync_release_tid, Tid}} ->
 	    do_release_tid(Tid),
 	    reply(From, {tid_released, Tid}),
 	    loop(State);
-	
+
 	{release_remote_non_pending, Node, Pending} ->
 	    release_remote_non_pending(Node, Pending),
 	    mnesia_monitor:mnesia_down(?MODULE, Node),
@@ -229,7 +229,7 @@ loop(State) ->
 	{get_table, From, LockTable} ->
 	    From ! {LockTable, ?ets_match_object(LockTable, '_')},
 	    loop(State);
-	
+
 	Msg ->
 	    error("~p got unexpected message: ~p~n", [?MODULE, Msg]),
 	    loop(State)
@@ -271,8 +271,8 @@ try_lock(Tid, Op, SimpleOp, Lock, Pid, Oid) ->
 	{queue, Lucky} ->
 	    ?dbg("Queued ~p ~p ~p ~p ~n", [Tid, Oid, Lock, Lucky]),
 	    %% Append to queue: Nice place for trace output
-	    ?ets_insert(mnesia_lock_queue, 
-			#queue{oid = Oid, tid = Tid, op = Op, 
+	    ?ets_insert(mnesia_lock_queue,
+			#queue{oid = Oid, tid = Tid, op = Op,
 			       pid = Pid, lucky = Lucky}),
 	    ?ets_insert(mnesia_tid_locks, {Tid, Oid, {queued, Op}})
     end.
@@ -315,12 +315,12 @@ grant_lock(Tid, write, Lock, Oid) ->
 %%    newer (higher tid) transactions may never wait on older ones,
 %% 2) When releasing the tids from the queue always begin with youngest (high tid)
 %%    because of 1) it will avoid the deadlocks.
-%% 3) TabLocks is the problem :-) They should not starve and not deadlock 
+%% 3) TabLocks is the problem :-) They should not starve and not deadlock
 %%    handle tablocks in queue as they had locks on unlocked records.
 
 can_lock(Tid, read, {Tab, Key}, AlreadyQ) when Key /= ?ALL ->
     %% The key is bound, no need for the other BIF
-    Oid = {Tab, Key}, 
+    Oid = {Tab, Key},
     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);
@@ -330,7 +330,7 @@ can_lock(Tid, read, Oid, AlreadyQ) -> % Whole tab
     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 -> 
+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}),
@@ -348,22 +348,22 @@ check_lock(Tid, Oid, [Lock | Locks], TabLocks, X, AlreadyQ, Type) ->
 	    check_lock(Tid, Oid, Locks, TabLocks, X, AlreadyQ, Type);
 	WaitForTid ->
 	    Queue = allowed_to_be_queued(WaitForTid,Tid),
-	    if Queue == true -> 
+	    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]),  
+			    [Oid, Lock, Tid, WaitForTid]),
 		    %% Test..
 		    {Tab, _Key} = Oid,
-		    HaveQ = (ets:lookup(mnesia_lock_queue, Oid) /= []) 
+		    HaveQ = (ets:lookup(mnesia_lock_queue, Oid) /= [])
 			orelse (ets:lookup(mnesia_lock_queue,{Tab,?ALL}) /= []),
-		    if 
-			HaveQ -> 
+		    if
+			HaveQ ->
 			    {no, WaitForTid};
-			true -> 
+			true ->
 			    check_lock(Tid,Oid,Locks,TabLocks,{queue,WaitForTid},AlreadyQ,Type)
 		    end;
-		    %%{no, WaitForTid};  Safe solution 
+		    %%{no, WaitForTid};  Safe solution
 	       true ->
 		    {no, WaitForTid}
 	    end
@@ -373,7 +373,7 @@ check_lock(_, _, [], [], X, {queue, bad_luck}, _) ->
     X;  %% The queue should be correct already no need to check it again
 
 check_lock(_, _, [], [], X = {queue, _Tid}, _AlreadyQ, _) ->
-    X;  
+    X;
 
 check_lock(Tid, Oid, [], [], X, AlreadyQ, Type) ->
     {Tab, Key} = Oid,
@@ -387,7 +387,7 @@ check_lock(Tid, Oid, [], [], X, AlreadyQ, Type) ->
 	    %% If there is a queue on that object, read_lock shouldn't be granted
 	    ObjLocks = ets:lookup(mnesia_lock_queue, Oid),
 	    case max(ObjLocks) of
-		empty -> 
+		empty ->
 		    check_queue(Tid, Tab, X, AlreadyQ);
 		ObjL ->
 		    case allowed_to_be_queued(ObjL,Tid) of
@@ -407,12 +407,12 @@ check_lock(Tid, Oid, [], TabLocks, X, AlreadyQ, Type) ->
 allowed_to_be_queued(WaitForTid, Tid) ->
     case get(pid_sort_order) of
 	undefined -> WaitForTid > Tid;
-	r9b_plain -> 
+	r9b_plain ->
 	    cmp_tid(true, WaitForTid, Tid) =:= 1;
-	standard  -> 
+	standard  ->
 	    cmp_tid(false, WaitForTid, Tid) =:= 1
-    end.	    
-	    
+    end.
+
 %% Check queue for conflicting locks
 %% Assume that all queued locks belongs to other tid's
 
@@ -421,25 +421,25 @@ check_queue(Tid, Tab, X, AlreadyQ) ->
     Greatest = max(TabLocks),
     case Greatest of
 	empty ->  X;
-	Tid ->    X; 
-	WaitForTid -> 
+	Tid ->    X;
+	WaitForTid ->
 	    case allowed_to_be_queued(WaitForTid,Tid) of
 		true ->
 		    {queue, WaitForTid};
-		false when AlreadyQ =:= {no, bad_luck} -> 
+		false when AlreadyQ =:= {no, bad_luck} ->
 		    {no, WaitForTid}
 	    end
     end.
 
 sort_queue(QL) ->
     case get(pid_sort_order) of
-	undefined -> 
+	undefined ->
 	    lists:reverse(lists:keysort(#queue.tid, QL));
-	r9b_plain -> 
-	    lists:sort(fun(#queue{tid=X},#queue{tid=Y}) -> 
+	r9b_plain ->
+	    lists:sort(fun(#queue{tid=X},#queue{tid=Y}) ->
 			       cmp_tid(true, X, Y) == 1
 		       end, QL);
-	standard  -> 
+	standard  ->
 	    lists:sort(fun(#queue{tid=X},#queue{tid=Y}) ->
 			       cmp_tid(false, X, Y) == 1
 		       end, QL)
@@ -466,12 +466,12 @@ set_read_lock_on_all_keys(Tid, From, Tab, IxKey, Pos) ->
     	{queue, Lucky} ->
 	    ?dbg("Queued ~p ~p ~p ~p ~n", [Tid, Oid, Lock, Lucky]),
 	    %% Append to queue: Nice place for trace output
-	    ?ets_insert(mnesia_lock_queue, 
-			#queue{oid = Oid, tid = Tid, op = Op, 
+	    ?ets_insert(mnesia_lock_queue,
+			#queue{oid = Oid, tid = Tid, op = Op,
 			       pid = From, lucky = Lucky}),
 	    ?ets_insert(mnesia_tid_locks, {Tid, Oid, {queued, Op}})
     end.
-       
+
 %%%%%%%%%%%%%%%%%%%%%%%%%%%
 %% Release of locks
 
@@ -530,20 +530,20 @@ release_lock({Tid, Oid, Op}) ->
 
 rearrange_queue([{_Tid, {Tab, Key}, _} | Locks]) ->
     if
-	Key /= ?ALL->	    
-	    Queue =  
-		ets:lookup(mnesia_lock_queue, {Tab, ?ALL}) ++ 
+	Key /= ?ALL->
+	    Queue =
+		ets:lookup(mnesia_lock_queue, {Tab, ?ALL}) ++
 		ets:lookup(mnesia_lock_queue, {Tab, Key}),
-	    case Queue of 
-		[] -> 
+	    case Queue of
+		[] ->
 		    ok;
 		_ ->
 		    Sorted = sort_queue(Queue),
 		    try_waiters_obj(Sorted)
-	    end;	
-	true -> 
+	    end;
+	true ->
 	    Pat = ?match_oid_lock_queue({Tab, '_'}),
-	    Queue = ?ets_match_object(mnesia_lock_queue, Pat),	    
+	    Queue = ?ets_match_object(mnesia_lock_queue, Pat),
 	    Sorted = sort_queue(Queue),
 	    try_waiters_tab(Sorted)
     end,
@@ -556,7 +556,7 @@ try_waiters_obj([W | Waiters]) ->
     case try_waiter(W) of
 	queued ->
 	    no;
-	_ -> 	    
+	_ ->
 	    try_waiters_obj(Waiters)
     end;
 try_waiters_obj([]) ->
@@ -573,10 +573,10 @@ try_waiters_tab([W | Waiters]) ->
 	    end;
 	Oid ->
 	    case try_waiter(W) of
-		queued -> 	    
+		queued ->
 		    Rest = key_delete_all(Oid, #queue.oid, Waiters),
 		    try_waiters_tab(Rest);
-		_ ->		    
+		_ ->
 		    try_waiters_tab(Waiters)
 	    end
     end;
@@ -594,20 +594,20 @@ try_waiter(Oid, Op, SimpleOp, Lock, ReplyTo, Tid) ->
     case can_lock(Tid, Lock, Oid, {queue, bad_luck}) of
 	yes ->
 	    %% Delete from queue: Nice place for trace output
-	    ?ets_match_delete(mnesia_lock_queue, 
+	    ?ets_match_delete(mnesia_lock_queue,
 			      #queue{oid=Oid, tid = Tid, op = Op,
 				     pid = ReplyTo, lucky = '_'}),
-	    Reply = grant_lock(Tid, SimpleOp, Lock, Oid),	    
+	    Reply = grant_lock(Tid, SimpleOp, Lock, Oid),
 	    reply(ReplyTo,Reply),
 	    locked;
 	{queue, _Why} ->
 	    ?dbg("Keep ~p ~p ~p ~p~n", [Tid, Oid, Lock, _Why]),
-	    queued; % Keep waiter in queue	
+	    queued; % Keep waiter in queue
 	{no, Lucky} ->
 	    C = #cyclic{op = SimpleOp, lock = Lock, oid = Oid, lucky = Lucky},
 	    verbose("** WARNING ** Restarted transaction, possible deadlock in lock queue ~w: cyclic = ~w~n",
 		    [Tid, C]),
-	    ?ets_match_delete(mnesia_lock_queue, 
+	    ?ets_match_delete(mnesia_lock_queue,
 			      #queue{oid=Oid, tid = Tid, op = Op,
 				     pid = ReplyTo, lucky = '_'}),
 	    Reply = {not_granted, C},
@@ -645,7 +645,7 @@ mnesia_down(N, Pending) ->
 	    Pid ! {release_remote_non_pending, N, Pending}
     end.
 
-%% Aquire a write lock, but do a read, used by 
+%% Aquire a write lock, but do a read, used by
 %% mnesia:wread/1
 
 rwlock(Tid, Store, Oid) ->
@@ -657,9 +657,10 @@ rwlock(Tid, Store, Oid) ->
 	    Lock = write,
 	    case need_lock(Store, Tab, Key, Lock)  of
 		yes ->
-		    {Ns, Majority} = w_nodes(Tab),
+		    {Ns0, Majority} = w_nodes(Tab),
+		    Ns = [Node|lists:delete(Node,Ns0)],
 		    check_majority(Majority, Tab, Ns),
-		    Res = get_rwlocks_on_nodes(Ns, rwlock, Node, Store, Tid, Oid),
+		    Res = get_rwlocks_on_nodes(Ns, make_ref(), Store, Tid, Oid),
 		    ?ets_insert(Store, {{locks, Tab, Key}, Lock}),
 		    Res;
 		no ->
@@ -718,7 +719,7 @@ sticky_rwlock(Tid, Store, Oid) ->
     sticky_lock(Tid, Store, Oid, read_write).
 
 sticky_lock(Tid, Store, {Tab, Key} = Oid, Lock) ->
-    N = val({Tab, where_to_read}), 
+    N = val({Tab, where_to_read}),
     if
 	node() == N ->
 	    case need_lock(Store, Tab, Key, write) of
@@ -805,9 +806,9 @@ sticky_wlock_table(Tid, Store, Tab) ->
 %% aquire a wlock on Oid
 %% We store a {Tabname, write, Tid} in all locktables
 %% on all nodes containing a copy of Tabname
-%% We also store an item {{locks, Tab, Key}, write} in the 
+%% We also store an item {{locks, Tab, Key}, write} in the
 %% local store when we have aquired the lock.
-%% 
+%%
 wlock(Tid, Store, Oid) ->
     wlock(Tid, Store, Oid, _CheckMajority = true).
 
@@ -845,10 +846,10 @@ wlock_no_exist(Tid, Store, Tab, Ns) ->
 
 need_lock(Store, Tab, Key, LockPattern) ->
     TabL = ?ets_match_object(Store, {{locks, Tab, ?ALL}, LockPattern}),
-    if 
+    if
 	TabL == [] ->
 	    KeyL = ?ets_match_object(Store, {{locks, Tab, Key}, LockPattern}),
-	    if 
+	    if
 		KeyL == [] ->
 		    yes;
 		true  ->
@@ -865,7 +866,7 @@ del_debug() ->
     erase(mnesia_wlock_nodes).
 
 %% We first send lock request to the local node if it is part of the lockers
-%% then the first sorted node then to the rest of the lockmanagers on all 
+%% then the first sorted node then to the rest of the lockmanagers on all
 %% nodes holding a copy of the table
 
 get_wlocks_on_nodes([Node | Tail], Orig, Store, Request, Oid) ->
@@ -875,51 +876,31 @@ get_wlocks_on_nodes([Node | Tail], Orig, Store, Request, Oid) ->
     case node() of
 	Node -> %% Local done try one more
 	    get_wlocks_on_nodes(Tail, Orig, Store, Request, Oid);
-	_ ->    %% The first succeded cont with the rest  
+	_ ->    %% The first succeded cont with the rest
 	    get_wlocks_on_nodes(Tail, Store, Request),
 	    receive_wlocks(Tail, Orig, Store, Oid)
     end;
-get_wlocks_on_nodes([], Orig, _Store, _Request, _Oid) -> 
+get_wlocks_on_nodes([], Orig, _Store, _Request, _Oid) ->
     Orig.
 
 get_wlocks_on_nodes([Node | Tail], Store, Request) ->
     {?MODULE, Node} ! Request,
     ?ets_insert(Store,{nodes, Node}),
     get_wlocks_on_nodes(Tail, Store, Request);
-get_wlocks_on_nodes([], _, _) -> 
+get_wlocks_on_nodes([], _, _) ->
     ok.
 
-get_rwlocks_on_nodes([ReadNode|Tail], _Res, ReadNode, Store, Tid, Oid) ->
+get_rwlocks_on_nodes([ReadNode|Tail], Ref, Store, Tid, Oid) ->
     Op = {self(), {read_write, Tid, Oid}},
     {?MODULE, ReadNode} ! Op,
     ?ets_insert(Store, {nodes, ReadNode}),
-    Res = receive_wlocks([ReadNode], undefined, Store, Oid),
-    case node() of
-	ReadNode -> 
-	    get_rwlocks_on_nodes(Tail, Res, ReadNode, Store, Tid, Oid);
-	_ ->
-	    get_wlocks_on_nodes(Tail, Store, {self(), {write, Tid, Oid}}),
-	    receive_wlocks(Tail, Res, Store, Oid)
+    case receive_wlocks([ReadNode], Ref, Store, Oid) of
+	Ref ->
+	    get_rwlocks_on_nodes(Tail, Ref, Store, Tid, Oid);
+	Res ->
+	    get_wlocks_on_nodes(Tail, Res, Store, {self(), {write, Tid, Oid}}, Oid)
     end;
-get_rwlocks_on_nodes([Node | Tail], Res, ReadNode, Store, Tid, Oid) ->
-    Op = {self(), {write, Tid, Oid}},
-    {?MODULE, Node} ! Op,
-    ?ets_insert(Store, {nodes, Node}),
-    receive_wlocks([Node], undefined, Store, Oid),
-    if node() == Node ->
-	    get_rwlocks_on_nodes(Tail, Res, ReadNode, Store, Tid, Oid);
-       Res == rwlock -> %% Hmm	    
-	    Rest = lists:delete(ReadNode, Tail),
-	    Op2 = {self(), {read_write, Tid, Oid}},
-	    {?MODULE, ReadNode} ! Op2,
-	    ?ets_insert(Store, {nodes, ReadNode}),
-	    get_wlocks_on_nodes(Rest, Store, {self(), {write, Tid, Oid}}),
-	    receive_wlocks([ReadNode|Rest], undefined, Store, Oid);
-       true ->
-	    get_wlocks_on_nodes(Tail, Store, {self(), {write, Tid, Oid}}),
-	    receive_wlocks(Tail, Res, Store, Oid)
-    end;
-get_rwlocks_on_nodes([],Res,_,_,_,_) ->
+get_rwlocks_on_nodes([],Res,_,_,_) ->
     Res.
 
 receive_wlocks([], Res, _Store, _Oid) ->
@@ -944,8 +925,8 @@ receive_wlocks(Nodes = [This|Ns], Res, Store, Oid) ->
 	    Tail = lists:delete(Node,Nodes),
 	    Nonstuck = lists:delete(Sticky,Tail),
 	    [?ets_insert(Store, {nodes, NSNode}) || NSNode <- Nonstuck],
-	    case lists:member(Sticky,Tail) of		
-		true -> 		    
+	    case lists:member(Sticky,Tail) of
+		true ->
 		    sticky_flush(Nonstuck,Store),
 		    receive_wlocks([Sticky], Res, Store, Oid);
 		false ->
@@ -957,7 +938,7 @@ receive_wlocks(Nodes = [This|Ns], Res, Store, Oid) ->
 	    flush_remaining(Ns, This, Reason1)
     end.
 
-sticky_flush([], _) -> 
+sticky_flush([], _) ->
     del_debug(),
     ok;
 sticky_flush(Ns=[Node | Tail], Store) ->
@@ -991,7 +972,7 @@ opt_lookup_in_client(lookup_in_client, Oid, Lock) ->
 	    %% Table has been deleted from this node,
 	    %% restart the transaction.
 	    #cyclic{op = read, lock = Lock, oid = Oid, lucky = nowhere};
-	Val -> 
+	Val ->
 	    Val
     end;
 opt_lookup_in_client(Val, _Oid, _Lock) ->
@@ -1000,8 +981,8 @@ opt_lookup_in_client(Val, _Oid, _Lock) ->
 return_granted_or_nodes({_, ?ALL}   , Nodes) -> Nodes;
 return_granted_or_nodes({?GLOBAL, _}, Nodes) -> Nodes;
 return_granted_or_nodes(_           , _Nodes) -> granted.
-    
-%% We store a {Tab, read, From} item in the 
+
+%% We store a {Tab, read, From} item in the
 %% locks table on the node where we actually do pick up the object
 %% and we also store an item {lock, Oid, read} in our local store
 %% so that we can release any locks we hold when we commit.
@@ -1059,9 +1040,9 @@ rlock_get_reply(Node, Store, Oid, {granted, V}) ->
     ?ets_insert(Store, {{locks, Tab, Key}, read}),
     ?ets_insert(Store, {nodes, Node}),
     case opt_lookup_in_client(V, Oid, read) of
-	C = #cyclic{} -> 
+	C = #cyclic{} ->
 	    mnesia:abort(C);
-	Val -> 
+	Val ->
 	    Val
     end;
 rlock_get_reply(Node, Store, Oid, granted) ->
@@ -1079,7 +1060,7 @@ rlock_get_reply(Node, Store, Tab, {granted, V, RealKeys}) ->
 rlock_get_reply(_Node, _Store, _Oid, {not_granted, Reason}) ->
     exit({aborted, Reason});
 
-rlock_get_reply(_Node, Store, Oid, {switch, N2, Req}) ->    
+rlock_get_reply(_Node, Store, Oid, {switch, N2, Req}) ->
     ?ets_insert(Store, {nodes, N2}),
     {?MODULE, N2} ! Req,
     rlock_get_reply(N2, Store, Oid, l_req_rec(N2, Store)).
@@ -1095,7 +1076,7 @@ ixrlock(Tid, Store, Tab, IxKey, Pos) ->
 	    %%% Old code
 	    %% R = l_request(Node, {ix_read, Tid, Tab, IxKey, Pos}, Store),
 	    %% rlock_get_reply(Node, Store, Tab, R)
-	    
+
 	    case need_lock(Store, Tab, ?ALL, read) of
 		no when Node =:= node() ->
 		    ix_read_res(Tab,IxKey,Pos);