From 4f6bb246f69443549fbbd0f2abaf863243cb35e9 Mon Sep 17 00:00:00 2001
From: Stanislav Kinsbursky <skinsbursky@parallels.com>
Date: Mon, 24 Jun 2013 11:52:59 +0400
Subject: [PATCH] SUNRPC: PipeFS MOUNT notification optimization for dying
 clients

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@parallels.com>
Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
---
 net/sunrpc/clnt.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
index b4f17117b779d..f0339ae9bf37e 100644
--- a/net/sunrpc/clnt.c
+++ b/net/sunrpc/clnt.c
@@ -177,6 +177,8 @@ 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;
 }