[ofa-general] Re: [PATCH 11/12 -Rev2] IPoIB xmit API addition

[Krishna Kumar2]

Hi Evgeniy,

Evgeniy Polyakov <johnpol at 2ka.mipt.ru> wrote on 07/23/2007 04:18:26 PM:

> >  static void ipoib_ib_handle_tx_wc(struct net_device *dev, struct ib_wc
*wc)
> >  {
> >     struct ipoib_dev_priv *priv = netdev_priv(dev);
> > +   int i = 0, num_completions;
> > +   int tx_ring_index = priv->tx_tail & (ipoib_sendq_size - 1);
> >     unsigned int wr_id = wc->wr_id;
> > -   struct ipoib_tx_buf *tx_req;
> >     unsigned long flags;
> >
> >     ipoib_dbg_data(priv, "send completion: id %d, status: %d\n",
> > @@ -255,23 +256,57 @@ static void ipoib_ib_handle_tx_wc(struct
> >        return;
> >     }
> >
> > -   tx_req = &priv->tx_ring[wr_id];
> > +   num_completions = wr_id - tx_ring_index + 1;
> > +   if (num_completions <= 0)
> > +      num_completions += ipoib_sendq_size;
>
> Can this still be less than zero?

Should never happen, otherwise the TX code wrote on bad/unallocated
memory and would have crashed first.

Thanks,

- KK