On Tue, 24 Nov 2020 13:03:30 +0100 Łukasz Stelmach wrote:
> +static int
> +ax88796c_start_xmit(struct sk_buff *skb, struct net_device *ndev)
> +{
> + struct ax88796c_device *ax_local = to_ax88796c_device(ndev);
> +
> + skb_queue_tail(&ax_local->tx_wait_q, skb);
> + if (skb_queue_len(&ax_local->tx_wait_q) > TX_QUEUE_HIGH_WATER) {
> + netif_err(ax_local, tx_queued, ndev,
> + "Too many TX packets in queue %d\n",
> + skb_queue_len(&ax_local->tx_wait_q));
This will probably happen under heavy traffic. No need to print errors,
it's normal to back pressure.
> + netif_stop_queue(ndev);
> + }
> +
> + set_bit(EVENT_TX, &ax_local->flags);
> + schedule_work(&ax_local->ax_work);
> +
> + return NETDEV_TX_OK;
> +}
> +
> +static void
> +ax88796c_skb_return(struct ax88796c_device *ax_local, struct sk_buff *skb,
> + struct rx_header *rxhdr)
> +{
> + struct net_device *ndev = ax_local->ndev;
> + int status;
> +
> + do {
> + if (!(ndev->features & NETIF_F_RXCSUM))
> + break;
> +
> + /* checksum error bit is set */
> + if ((rxhdr->flags & RX_HDR3_L3_ERR) ||
> + (rxhdr->flags & RX_HDR3_L4_ERR))
> + break;
> +
> + /* Other types may be indicated by more than one bit. */
> + if ((rxhdr->flags & RX_HDR3_L4_TYPE_TCP) ||
> + (rxhdr->flags & RX_HDR3_L4_TYPE_UDP))
> + skb->ip_summed = CHECKSUM_UNNECESSARY;
> + } while (0);
> +
> + ax_local->stats.rx_packets++;
> + ax_local->stats.rx_bytes += skb->len;
> + skb->dev = ndev;
> +
> + skb->truesize = skb->len + sizeof(struct sk_buff);
> + skb->protocol = eth_type_trans(skb, ax_local->ndev);
> +
> + netif_info(ax_local, rx_status, ndev, "< rx, len %zu, type 0x%x\n",
> + skb->len + sizeof(struct ethhdr), skb->protocol);
> +
> + status = netif_rx(skb);
If I'm reading things right this is in process context, so netif_rx_ni()
> + if (status != NET_RX_SUCCESS)
> + netif_info(ax_local, rx_err, ndev,
> + "netif_rx status %d\n", status);
Again, it's inadvisable to put per packet prints without any rate
limiting in the data path.
