[PATCH 80/98] SUNRPC: PipeFS MOUNT notification optimization for dying clients

[Luis Henriques]

3.5.7.17 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Stanislav Kinsbursky <skinsbursky at parallels.com>

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