virtio: change comment in transmit

The original comment was not really informative or funny
as well as sexist. Replace it with a better explanation of
why the driver does stop and what the impacts are.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 59b0e97..4e84236 100644 (file)
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -939,8 +939,12 @@ static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
        skb_orphan(skb);
        nf_reset(skb);
 
-       /* Apparently nice girls don't return TX_BUSY; stop the queue
-        * before it gets out of hand.  Naturally, this wastes entries. */
+       /* It is better to stop queue if running out of space
+        * instead of forcing queuing layer to requeue the skb
+        * by returning TX_BUSY (and cause a BUG message).
+        * Since most packets only take 1 or 2 ring slots
+        * this means 16 slots are typically wasted.
+        */
        if (sq->vq->num_free < 2+MAX_SKB_FRAGS) {
                netif_stop_subqueue(dev, qnum);
                if (unlikely(!virtqueue_enable_cb_delayed(sq->vq))) {