Re: [dpdk-dev] [PATCH] net/af_xdp: enqueue buf ring when allocate Tx queue fails

[David Marchand <david.marchand@redhat.com>]

On Tue, Apr 9, 2019 at 5:24 PM Xiaolong Ye <xiaolong.ye@intel.com> wrote:

> When it fails to allocate enough slots in Tx queue for transmitting
> packets, we need to return the dequeued addrs to buf ring.
>
> Fixes: f1debd77efaf ("net/af_xdp: introduce AF_XDP PMD")
>
> Signed-off-by: Xiaolong Ye <xiaolong.ye@intel.com>
> ---
>  drivers/net/af_xdp/rte_eth_af_xdp.c | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/drivers/net/af_xdp/rte_eth_af_xdp.c
> b/drivers/net/af_xdp/rte_eth_af_xdp.c
> index 007a1c6b4..5cc643ce2 100644
> --- a/drivers/net/af_xdp/rte_eth_af_xdp.c
> +++ b/drivers/net/af_xdp/rte_eth_af_xdp.c
> @@ -276,6 +276,7 @@ eth_af_xdp_tx(void *queue, struct rte_mbuf **bufs,
> uint16_t nb_pkts)
>
>         if (xsk_ring_prod__reserve(&txq->tx, nb_pkts, &idx_tx) != nb_pkts)
> {
>                 kick_tx(txq);
> +               rte_ring_enqueue_bulk(umem->buf_ring, addrs, nb_pkts,
> NULL);
>                 return 0;
>         }
>
> --
> 2.17.1
>

Looks good to me.
But I have an additional question.

After the for loop that only picks the mbufs it can copy to the xdp desc,
is it normal to call xsk_ring_prod__submit(&txq->tx, nb_pkts); rather than
with valid count ?

-- 
David Marchand