Subject: + ipcmsg-introduce-lockless-functions-to-obtain-the-ipc-object.patch added to -mm tree
To: davidlohr.bueso@xxxxxx,andi@xxxxxxxxxxxxxx,riel@xxxxxxxxxx
From: akpm@xxxxxxxxxxxxxxxxxxxx
Date: Fri, 24 May 2013 13:17:40 -0700
The patch titled
Subject: ipc,msg: introduce lockless functions to obtain the ipc object
has been added to the -mm tree. Its filename is
ipcmsg-introduce-lockless-functions-to-obtain-the-ipc-object.patch
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/SubmitChecklist when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Davidlohr Bueso <davidlohr.bueso@xxxxxx>
Subject: ipc,msg: introduce lockless functions to obtain the ipc object
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 <davidlohr.bueso@xxxxxx>
Cc: Andi Kleen <andi@xxxxxxxxxxxxxx>
Cc: Rik van Riel <riel@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
ipc/msg.c | 21 +++++++++++++++++++++
1 file changed, 21 insertions(+)
diff -puN ipc/msg.c~ipcmsg-introduce-lockless-functions-to-obtain-the-ipc-object ipc/msg.c
--- a/ipc/msg.c~ipcmsg-introduce-lockless-functions-to-obtain-the-ipc-object
+++ a/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 -mm which might be from davidlohr.bueso@xxxxxx are
linux-next.patch
shm-fix-null-pointer-deref-when-userspace-specifies-invalid-hugepage-size-fix.patch
softirq-use-_ret_ip_.patch
ipc-move-rcu-lock-out-of-ipc_addid.patch
ipc-introduce-ipc-object-locking-helpers.patch
ipc-close-open-coded-spin-lock-calls.patch
ipc-move-locking-out-of-ipcctl_pre_down_nolock.patch
ipcmsg-shorten-critical-region-in-msgctl_down.patch
ipcmsg-introduce-msgctl_nolock.patch
ipcmsg-introduce-lockless-functions-to-obtain-the-ipc-object.patch
ipcmsg-make-msgctl_nolock-lockless.patch
ipcmsg-shorten-critical-region-in-msgsnd.patch
ipcmsg-shorten-critical-region-in-msgrcv.patch
ipc-remove-unused-functions.patch
--
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
