On Thu, 2014-10-30 at 12:46 -0400, Sowmini Varadhan wrote:

Use multple Tx netdev queues for sunvnet by supporting a one-to-one
mapping between vnet_port and Tx queue. Provide a ndo_select_queue
indirection (vnet_select_queue()) which selects the queue based
on the peer that would be selected in vnet_start_xmit()

Signed-off-by: Sowmini Varadhan <redacted>

[...]

+static void maybe_tx_wakeup(struct vnet_port *port)
 {
-	struct net_device *dev = vp->dev;
+	struct netdev_queue *txq;
 
-	netif_tx_lock(dev);
-	if (likely(netif_queue_stopped(dev))) {
-		struct vnet_port *port;
-		int wake = 1;
-
-		rcu_read_lock();
-		list_for_each_entry_rcu(port, &vp->port_list, list) {
-			struct vio_dring_state *dr;
-
-			dr = &port->vio.drings[VIO_DRIVER_TX_RING];
-			if (vnet_tx_dring_avail(dr) <
-			    VNET_TX_WAKEUP_THRESH(dr)) {
-				wake = 0;
-				break;
-			}
-		}
-		rcu_read_unlock();
-		if (wake)
-			netif_wake_queue(dev);
+	txq = netdev_get_tx_queue(port->vp->dev, port->q_index);
+	__netif_tx_lock(txq, smp_processor_id());
+	if (likely(netif_tx_queue_stopped(txq))) {
+		struct vio_dring_state *dr;
+
+		dr = &port->vio.drings[VIO_DRIVER_TX_RING];

You seem to have dropped the condition for the netif_tx_wake_queue(),
which I would guess based on the old code should be:

		if (vnet_tx_dring_avail(dr) >= VNET_TX_WAKEUP_THRESH(dr))

+			netif_tx_wake_queue(txq);
 	}
-	netif_tx_unlock(dev);
+	__netif_tx_unlock(txq);
 }

[...]

-- 
Ben Hutchings
Beware of programmers who carry screwdrivers. - Leonard Brandwein