Re: [PATCH for-2.6.35] virtio_net: fix oom handling on tx

["Michael S. Tsirkin" <mst@redhat.com>]

On Mon, Jun 21, 2010 at 07:53:43PM +0930, Rusty Russell wrote:
> On Mon, 21 Jun 2010 06:03:16 pm Michael S. Tsirkin wrote:
> > On Mon, Jun 21, 2010 at 12:13:49PM +0930, Rusty Russell wrote:
> > > -		return NETDEV_TX_BUSY;
> > > +		kfree_skb(skb);
> > > +		return NETDEV_TX_OK;
> > 
> > If we do so, let's increment the dropped counter and/or error counter?
> 
> Yep, here's the extra change:

Looks good to me.

> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> --- a/drivers/net/virtio_net.c
> +++ b/drivers/net/virtio_net.c
> @@ -571,14 +571,16 @@ static netdev_tx_t start_xmit(struct sk_
>  	/* This can happen with OOM and indirect buffers. */
>  	if (unlikely(capacity < 0)) {
>  		if (net_ratelimit()) {
> -			if (likely(capacity == -ENOMEM))
> +			if (likely(capacity == -ENOMEM)) {
>  				dev_warn(&dev->dev,
>  					 "TX queue failure: out of memory\n");
> -			else
> +			} else {
> +				dev->stats.tx_fifo_errors++;
>  				dev_warn(&dev->dev,
>  					 "Unexpected TX queue failure: %d\n",
>  					 capacity);
>  		}
> +		dev->stats.tx_dropped++;
>  		kfree_skb(skb);
>  		return NETDEV_TX_OK;
>  	}