[ 3.5.y.z extended stable ] Patch "SUNRPC: PipeFS MOUNT notification optimization for dying" has been added to staging queue

[Luis Henriques]

This is a note to let you know that I have just added a patch titled

    SUNRPC: PipeFS MOUNT notification optimization for dying

to the linux-3.5.y-queue branch of the 3.5.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.5.y-queue

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.5.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From e64ca0b69577d5094ed7dad1482158d157ffd1c9 Mon Sep 17 00:00:00 2001
From: Stanislav Kinsbursky <skinsbursky at parallels.com>
Date: Mon, 24 Jun 2013 11:52:59 +0400
Subject: [PATCH] SUNRPC: PipeFS MOUNT notification optimization for dying
 clients

commit 4f6bb246f69443549fbbd0f2abaf863243cb35e9 upstream.

Not need to create pipes for dying client. So just skip them.

Note: we can safely dereference the client structure, because notification
caller is holding sn->pipefs_sb_lock.

Signed-off-by: Stanislav Kinsbursky <skinsbursky at parallels.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust at netapp.com>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 net/sunrpc/clnt.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
index 631a75d..e0fd6a7 100644
--- a/net/sunrpc/clnt.c
+++ b/net/sunrpc/clnt.c
@@ -179,6 +179,8 @@ static inline int rpc_clnt_skip_event(struct rpc_clnt *clnt, unsigned long event
 	if (((event == RPC_PIPEFS_MOUNT) && clnt->cl_dentry) ||
 	    ((event == RPC_PIPEFS_UMOUNT) && !clnt->cl_dentry))
 		return 1;
+	if ((event == RPC_PIPEFS_MOUNT) && atomic_read(&clnt->cl_count) == 0)
+		return 1;
 	return 0;
 }

--
1.8.1.2