SUNRPC: xprt_clear_locked() only needs release memory semantics

The clearing of the XPRT_LOCKED bit has to happen after we clear
xprt->snd_task, but we don't require any extra memory barriers after
that.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

net/sunrpc/xprt.c

@@ -246,11 +246,9 @@ EXPORT_SYMBOL_GPL(xprt_find_transport_ident);
 static void xprt_clear_locked(struct rpc_xprt *xprt)
 {
 	xprt->snd_task = NULL;
-	if (!test_bit(XPRT_CLOSE_WAIT, &xprt->state)) {
-		smp_mb__before_atomic();
-		clear_bit(XPRT_LOCKED, &xprt->state);
-		smp_mb__after_atomic();
-	} else
+	if (!test_bit(XPRT_CLOSE_WAIT, &xprt->state))
+		clear_bit_unlock(XPRT_LOCKED, &xprt->state);
+	else
 		queue_work(xprtiod_workqueue, &xprt->task_cleanup);
 }