Re: [bpf-next V4 PATCH 5/8] xdp: introduce xdp_return_frame_rx_napi

Jesper Dangaard Brouer
2018-05-18T20:46:13Z

On Fri, 18 May 2018 15:34:57 +0200
Jesper Dangaard Brouer <brouer@redhat.com> wrote:

> When sending an xdp_frame through xdp_do_redirect call, then error
> cases can happen where the xdp_frame needs to be dropped, and
> returning an -errno code isn't sufficient/possible any-longer
> (e.g. for cpumap case). This is already fully supported, by simply
> calling xdp_return_frame.
>
> This patch is an optimization, which provides xdp_return_frame_rx_napi,
> which is a faster variant for these error cases. It take advantage of
> the protection provided by XDP RX running under NAPI protection.
>
> This change is mostly relevant for drivers using the page_pool
> allocator as it can take advantage of this. (Tested with mlx5).

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>

Ups, forgot my SoB... hope it's sufficient to add it this way.

--
Best regards,
Jesper Dangaard Brouer
MSc.CS, Principal Kernel Engineer at Red Hat
LinkedIn: http://www.linkedin.com/in/brouer