Re: [UNIKRAFT/LWIP PATCH v4 5/5] uknetdev: Retrieve `ioalign` from device

[Sharan Santhanam <sharan.santhanam@xxxxxxxxx>]

Hello Simon,

Thanks for the work.

Reviewed-by: Sharan Santhanam <sharan.santhanam@xxxxxxxxx>

Thanks & Regards

Sharan

On 10/30/20 7:31 PM, Simon Kuenzer wrote:
> Retrieve `ioalign` from uknetdev device and apply it to packet buffer
> allocations.
>
> Signed-off-by: Simon Kuenzer <simon.kuenzer@xxxxxxxxx>
> ---
>   uknetdev.c | 23 ++++++++++++-----------
>   1 file changed, 12 insertions(+), 11 deletions(-)
>
> diff --git a/uknetdev.c b/uknetdev.c
> index 7b689f9..50c6460 100644
> --- a/uknetdev.c
> +++ b/uknetdev.c
> @@ -67,6 +67,7 @@ struct lwip_netdev_data {
>         struct uk_alloc *pkt_a;
>         uint16_t rx_headroom;
>         uint16_t tx_headroom;
> +       uint16_t ioalign; /* required alignment for RX/TX buffers */
>   #ifdef CONFIG_HAVE_SCHED
>         struct uk_thread *poll_thread; /* Thread per device */
>         char *_name; /* Thread name */
> @@ -99,7 +100,7 @@ static uint16_t netif_alloc_rxpkts(void *argp, struct 
> uk_netbuf *nb[],
>         for (i = 0; i < count; ++i) {
>                 nb[i] = lwip_alloc_netbuf(lwip_data->pkt_a,
>                                           UKNETDEV_BUFLEN,
> -                                         1,
> +                                         lwip_data->ioalign,
>                                           lwip_data->rx_headroom);
>                 if (!nb[i]) {
>                         /* we run out of memory */
> @@ -116,7 +117,6 @@ static err_t uknetdev_output(struct netif *nf, struct pbuf 
> *p)
>         struct lwip_netdev_data *lwip_data;
>         struct pbuf *q;
>         struct uk_netbuf *nb;
> -       void *allocation;
>         char *wpos;
>         int ret;
>   
> @@ -126,14 +126,13 @@ static err_t uknetdev_output(struct netif *nf, struct pbuf *p)
>         lwip_data = (struct lwip_netdev_data *) dev->scratch_pad;
>         UK_ASSERT(lwip_data);
>   
> -	allocation = uk_malloc(lwip_data->pkt_a, UKNETDEV_BUFLEN);
> -       if (!allocation)
> +       nb = uk_netbuf_alloc_buf(lwip_data->pkt_a,
> +                                UKNETDEV_BUFLEN,
> +                                lwip_data->ioalign,
> +                                lwip_data->tx_headroom,
> +                                0, NULL);
> +       if (!nb)
>                 return ERR_MEM;
> -       nb = uk_netbuf_prepare_buf(allocation, UKNETDEV_BUFLEN,
> -                                  lwip_data->tx_headroom, 0, NULL);
> -       UK_ASSERT(nb);
> -       nb->_a = a; /* register allocator for free operation */
> -       nb->_b = allocation;
>   
>   	if (unlikely(p->tot_len > uk_netbuf_tailroom(nb))) {
>                 LWIP_DEBUGF(NETIF_DEBUG,
> @@ -494,12 +493,14 @@ err_t uknetdev_init(struct netif *nf)
>         lwip_data->rx_headroom = info.nb_encap_rx;
>         lwip_data->tx_headroom = info.nb_encap_tx;
>   #endif
> +       lwip_data->ioalign     = info.ioalign;
>         lwip_data->pkt_a       = a;
>   
>   	LWIP_DEBUGF(NETIF_DEBUG,
> -                   ("%s: %c%c%u: Need headroom rx:%"PRIu16", tx:%"PRIu16"\n",
> +                   ("%s: %c%c%u: Headroom rx:%"PRIu16", tx:%"PRIu16"; I/O align: 
> 0x%"PRIx16"\n",
>                      __func__, nf->name[0], nf->name[1], nf->num,
> -                    lwip_data->rx_headroom, lwip_data->tx_headroom));
> +                    lwip_data->rx_headroom, lwip_data->tx_headroom,
> +                    lwip_data->ioalign));
>   
>   	/*
>          * Device configuration,