Re: [PATCH RFC net-next 03/19] net: dsa: tag_ar9331: add .flow_dissect() callback

From: Florian Fainelli
Date: Mon Dec 30 2019 - 13:22:46 EST


On 12/30/19 6:30 AM, Alexander Lobakin wrote:
> ...to make RPS work correctly if user would like to configure it.
> Misc: fix identation of ar9331_netdev_ops structure.
>
> Signed-off-by: Alexander Lobakin <alobakin@xxxxxxxx>
> ---
> net/dsa/tag_ar9331.c | 18 +++++++++++++-----
> 1 file changed, 13 insertions(+), 5 deletions(-)
>
> diff --git a/net/dsa/tag_ar9331.c b/net/dsa/tag_ar9331.c
> index 466ffa92a474..399ca21ec03b 100644
> --- a/net/dsa/tag_ar9331.c
> +++ b/net/dsa/tag_ar9331.c
> @@ -83,12 +83,20 @@ static struct sk_buff *ar9331_tag_rcv(struct sk_buff *skb,
> return skb;
> }
>
> +static void ar9331_tag_flow_dissect(const struct sk_buff *skb, __be16 *proto,
> + int *offset)
> +{
> + *offset = AR9331_HDR_LEN;
> + *proto = *(__be16 *)skb->data;

If we provided an offset from the beginning of the frame, then there is
no need to call .flow_dissect() at all and we can just return the
dsa_device_ops::overhead and offset_start (whatever is the name we pick)
and avoid a function call.

> +}
> +
> static const struct dsa_device_ops ar9331_netdev_ops = {
> - .name = "ar9331",
> - .proto = DSA_TAG_PROTO_AR9331,
> - .xmit = ar9331_tag_xmit,
> - .rcv = ar9331_tag_rcv,
> - .overhead = AR9331_HDR_LEN,
> + .name = "ar9331",
> + .proto = DSA_TAG_PROTO_AR9331,
> + .xmit = ar9331_tag_xmit,
> + .rcv = ar9331_tag_rcv,
> + .flow_dissect = ar9331_tag_flow_dissect,
> + .overhead = AR9331_HDR_LEN,
> };
>
> MODULE_LICENSE("GPL v2");
>


--
Florian