SUNRPC: another pmap wakeup fix

Don't wake up bind waiters if a task finds that another task is already
trying to bind.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

net/sunrpc/pmap_clnt.c

@@ -101,14 +101,14 @@ void rpc_getport(struct rpc_task *task)
 	/* Autobind on cloned rpc clients is discouraged */
 	BUG_ON(clnt->cl_parent != clnt);
 
+	status = -EACCES;		/* tell caller to check again */
+	if (xprt_test_and_set_binding(xprt))
+		goto bailout_nowake;
+
 	/* Put self on queue before sending rpcbind request, in case
 	 * pmap_getport_done completes before we return from rpc_run_task */
 	rpc_sleep_on(&xprt->binding, task, NULL, NULL);
 
-	status = -EACCES;		/* tell caller to check again */
-	if (xprt_test_and_set_binding(xprt))
-		goto bailout_nofree;
-
 	/* Someone else may have bound if we slept */
 	status = 0;
 	if (xprt_bound(xprt))
@@ -143,8 +143,9 @@ bailout:
 	pmap_map_free(map);
 	xprt_put(xprt);
 bailout_nofree:
-	task->tk_status = status;
 	pmap_wake_portmap_waiters(xprt, status);
+bailout_nowake:
+	task->tk_status = status;
 }
 
 #ifdef CONFIG_ROOT_NFS