SUNRPC: Give credential cache a local spinlock

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/net/sunrpc/auth_unix.c b/net/sunrpc/auth_unix.c
index f7ff6ad..205878a 100644
--- a/net/sunrpc/auth_unix.c
+++ b/net/sunrpc/auth_unix.c
@@ -213,6 +213,11 @@
 	return p;
 }
 
+void __init rpc_init_authunix(void)
+{
+	spin_lock_init(&unix_cred_cache.lock);
+}
+
 const struct rpc_authops authunix_ops = {
 	.owner		= THIS_MODULE,
 	.au_flavor	= RPC_AUTH_UNIX,