+ more people
On Wed, 8 Aug 2018 17:27:05 +0200 Marek Behún wrote:
> For some reason on Armada 3720 boards (EspressoBin and Turris Mox) the
> networking driver behaves weirdly when using napi_gro_receive.
>
> For example downloading a big file from a local network (low ping) is
> fast, but when downloading from a remote server (higher ping), the
> download speed is at first high but drops rapidly to almost nothing or
> absolutely nothing.
We also met this issue on some berlin platforms. I tried to fix the bug,
but no clue so far.
>
> This is fixed when using netif_receive_skb instead of napi_gro_receive.
This is a workaround. The good news is this workaround also fixes the issue
we saw on berlin.
>
> Signed-off-by: Marek Behun <marek.be...@nic.cz>
> Cc: Russell King - ARM Linux <li...@armlinux.org.uk>
> Cc: netdev@vger.kernel.org
>
> diff --git a/drivers/net/ethernet/marvell/mvneta.c
> b/drivers/net/ethernet/marvell/mvneta.c
> index 0ad2f3f7da85..27f3017d94c5 100644
> --- a/drivers/net/ethernet/marvell/mvneta.c
> +++ b/drivers/net/ethernet/marvell/mvneta.c
> @@ -1959,7 +1959,10 @@ static int mvneta_rx_swbm(struct mvneta_port *pp, int
> rx_todo,
>
> skb->protocol = eth_type_trans(skb, dev);
> mvneta_rx_csum(pp, rx_status, skb);
> - napi_gro_receive(&port->napi, skb);
> + if (pp->neta_armada3700)
> + netif_receive_skb(skb);
> + else
> + napi_gro_receive(&port->napi, skb);
>
> rcvd_pkts++;
> rcvd_bytes += rx_bytes;
> @@ -2001,7 +2004,10 @@ static int mvneta_rx_swbm(struct mvneta_port *pp, int
> rx_todo,
>
> mvneta_rx_csum(pp, rx_status, skb);
>
> - napi_gro_receive(&port->napi, skb);
> + if (pp->neta_armada3700)
> + netif_receive_skb(skb);
> + else
> + napi_gro_receive(&port->napi, skb);
> }
>
> if (rcvd_pkts) {
