RE: [PATCH net-next v25 06/13] rtase: Implement .ndo_start_xmit function

[Justin Lai]

> On Mon, 29 Jul 2024 14:21:14 +0800 Justin Lai wrote:
> > +     stop_queue = !netif_subqueue_maybe_stop(dev, ring->index,
> > +                                             rtase_tx_avail(ring),
> > +
> RTASE_TX_STOP_THRS,
> > +
> RTASE_TX_START_THRS);
> > +
> > +     if (door_bell || stop_queue)
> > +             rtase_w8(tp, RTASE_TPPOLL, BIT(ring->index));
> > +
> > +     return NETDEV_TX_OK;
> > +
> > +err_dma_1:
> > +     ring->skbuff[entry] = NULL;
> > +     rtase_tx_clear_range(ring, ring->cur_idx + 1, frags);
> > +
> > +err_dma_0:
> > +     tp->stats.tx_dropped++;
> > +     dev_kfree_skb_any(skb);
> > +     return NETDEV_TX_OK;
> > +
> > +err_stop:
> > +     netif_stop_queue(dev);
> > +     tp->stats.tx_dropped++;
> > +     return NETDEV_TX_BUSY;
> 
> If you're dropping a packet you should somehow check that the previous xmit
> didn't enqueue a packet to the ring and skip the doorbell because door_bell
> was false. If that's the case you have to ring the doorbell now.
> 
> Also you shouldn't increment dropped if you return TX_BUSY.

Thank you for your response. I will modify it.
> 
> Please fix these issues in the driver you're copying from, too.

I will inform the person responsible for the R8169 of the issues we've
identified and discuss what modifications need to be made.

Thanks
Justin