Re: Intel 800 series 100Gbe NIC with XDP

[Jesper Dangaard Brouer <brouer@redhat.com>]

On Mon, 29 Jul 2019 16:27:01 -0700
Zvi Effron <zeffron@riotgames.com> wrote:

> Hello all,
> 
> I was wondering if anyone knew if the upcoming 800 series Intel NICs
> with 100gbe support XDP? I don't yet see a new driver for them, but
> they may be reusing the i40e driver, or I may have missed it? If they
> do support it, do they maybe also support hardware mode (as opposed to
> driver mode)?

Good to see that Intel customers are requesting XDP support, for new HW
and associated drivers.

AFAIK Linux kernel driver is called ICE for Intel 800 series NIC[1]
(which supports 100/50/25/10 Gbit/s Ethernet).  (p.s. I don't have this
hardware in my testlab).

It is located in the kernel tree[2]: drivers/net/ethernet/intel/ice/.
Reading and grepping the code for 'xdp', reveals that this driver
doesn't support XDP.  So, I guess you need to buy your 100G hardware
from another vendor, or convince Intel to add XDP support.


Code details: Strangely it looks like this driver always does a memcpy
of the headers into linear part of a 256 bytes SKB, and attach the
payload as a SKB "fragment". (I wonder why this was chosen?)
  It should still be easy to add a XDP step before doing this (in
ice_clean_rx_irq() just after call to ice_get_rx_buf())


[1] https://www.intel.com/content/www/us/en/architecture-and-technology/ethernet/introducing-800-series.html
[2] https://github.com/torvalds/linux/tree/master/drivers/net/ethernet/intel/ice
-- 
Best regards,
  Jesper Dangaard Brouer
  MSc.CS, Principal Kernel Engineer at Red Hat
  LinkedIn: http://www.linkedin.com/in/brouer