On Tue, Feb 14, 2017 at 10:46 AM, Jesper Dangaard Brouer
<bro...@redhat.com> wrote:
>
>
> With this Intel driver page count based recycle approach, the recycle
> size is tied to the size of the RX ring. As Eric and Tariq discovered.
> And for other performance reasons (memory footprint of walking RX ring
> data-structures), don't want to increase the RX ring sizes. Thus, it
> create two opposite performance needs. That is why I think a more
> explicit approach with a pool is more attractive.
>
> How is this approach doing to work for XDP?
> (XDP doesn't "share" the page, and in-general we don't want the extra
> atomic.)
>
> We absolutely need recycling with XDP, when transmitting out another
> device, and the other devices DMA-TX completion need some way of
> returning this page.
> What is basically needed is a standardized callback to allow the remote
> driver to return the page to the originating driver. As we don't have
> a NDP for XDP-forward/transmit yet, we could pass this callback as a
> parameter along with the packet-page to send?
>
>
mlx4 already has a cache for XDP.
I believe I did not change this part, it still should work.
commit d576acf0a22890cf3f8f7a9b035f1558077f6770
Author: Brenden Blanco <bbla...@plumgrid.com>
Date: Tue Jul 19 12:16:52 2016 -0700
net/mlx4_en: add page recycle to prepare rx ring for tx support
I have not checked if recent Tom work added core infra for this cache.
