This is a note to let you know that I've just added the patch titled

    ipc,msg: introduce lockless functions to obtain the ipc object

to the 3.10-stable tree which can be found at:
    
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     ipc-msg-introduce-lockless-functions-to-obtain-the-ipc-object.patch
and it can be found in the queue-3.10 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.


>From a5001a0d9768568de5d613c3b3a5b9c7721299da Mon Sep 17 00:00:00 2001
From: Davidlohr Bueso <[email protected]>
Date: Mon, 8 Jul 2013 16:01:15 -0700
Subject: ipc,msg: introduce lockless functions to obtain the ipc object

From: Davidlohr Bueso <[email protected]>

commit a5001a0d9768568de5d613c3b3a5b9c7721299da upstream.

Add msq_obtain_object() and msq_obtain_object_check(), which will allow
us to get the ipc object without acquiring the lock.  Just as with
semaphores, these functions are basically wrappers around
ipc_obtain_object*().

Signed-off-by: Davidlohr Bueso <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Rik van Riel <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Cc: Mike Galbraith <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 ipc/msg.c |   21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

--- a/ipc/msg.c
+++ b/ipc/msg.c
@@ -166,6 +166,27 @@ static inline struct msg_queue *msg_lock
        return container_of(ipcp, struct msg_queue, q_perm);
 }
 
+static inline struct msg_queue *msq_obtain_object(struct ipc_namespace *ns, 
int id)
+{
+       struct kern_ipc_perm *ipcp = ipc_obtain_object(&msg_ids(ns), id);
+
+       if (IS_ERR(ipcp))
+               return ERR_CAST(ipcp);
+
+       return container_of(ipcp, struct msg_queue, q_perm);
+}
+
+static inline struct msg_queue *msq_obtain_object_check(struct ipc_namespace 
*ns,
+                                                       int id)
+{
+       struct kern_ipc_perm *ipcp = ipc_obtain_object_check(&msg_ids(ns), id);
+
+       if (IS_ERR(ipcp))
+               return ERR_CAST(ipcp);
+
+       return container_of(ipcp, struct msg_queue, q_perm);
+}
+
 static inline void msg_rmid(struct ipc_namespace *ns, struct msg_queue *s)
 {
        ipc_rmid(&msg_ids(ns), &s->q_perm);


Patches currently in stable-queue which might be from [email protected] are

queue-3.10/ipc-msg-introduce-lockless-functions-to-obtain-the-ipc-object.patch
queue-3.10/ipc-msg-shorten-critical-region-in-msgctl_down.patch
queue-3.10/ipc-remove-unused-functions.patch
queue-3.10/ipc-msg-introduce-msgctl_nolock.patch
queue-3.10/ipc-move-rcu-lock-out-of-ipc_addid.patch
queue-3.10/ipc-msg-shorten-critical-region-in-msgsnd.patch
queue-3.10/ipc-introduce-ipc-object-locking-helpers.patch
queue-3.10/ipc-msg-shorten-critical-region-in-msgrcv.patch
queue-3.10/ipc-msg-make-msgctl_nolock-lockless.patch
queue-3.10/ipc-move-locking-out-of-ipcctl_pre_down_nolock.patch
queue-3.10/ipc-close-open-coded-spin-lock-calls.patch
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