From: stephen hemminger Date: Tue, 24 Mar 2015 23:22:07 +0000 (-0700) Subject: virtio: change comment in transmit X-Git-Tag: v4.1-rc1~128^2~146 X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=d631b94e7a15277858ec5f88d674d93080506999;p=uclinux-h8%2Flinux.git 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 Signed-off-by: David S. Miller --- diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 59b0e9754ae3..4e84236b62ce 100644 --- 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))) {