lan78xx: throttle TX path at slower than SuperSpeed USB

Throttle TX path only at slower than SuperSpeed USB.
SuperSpeed USB has enough bandwidth to maintain GigE.

Signed-off-by: Woojung Huh <woojung.huh@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/usb/lan78xx.c b/drivers/net/usb/lan78xx.c
index 650e71604d861d0a8cc44d1530e8996275d271bc..1c299b8a162d7243c5ae94b96618c3763083e91e 100644 (file)
--- a/drivers/net/usb/lan78xx.c
+++ b/drivers/net/usb/lan78xx.c
@@ -2263,7 +2263,9 @@ netdev_tx_t lan78xx_start_xmit(struct sk_buff *skb, struct net_device *net)
        if (skb2) {
                skb_queue_tail(&dev->txq_pend, skb2);
 
-               if (skb_queue_len(&dev->txq_pend) > 10)
+               /* throttle TX patch at slower than SUPER SPEED USB */
+               if ((dev->udev->speed < USB_SPEED_SUPER) &&
+                   (skb_queue_len(&dev->txq_pend) > 10))
                        netif_stop_queue(net);
        } else {
                netif_dbg(dev, tx_err, dev->net,