Subject: Re: [PATCH v8 bpf-next 00/10] veth: Driver XDP

From: Jesper Dangaard Brouer <[email-masked]>
Date: Fri, 3 Aug 2018 11:45:38 +0200

On Fri,  3 Aug 2018 16:58:08 +0900
Toshiaki Makita <[email-masked]> wrote:

> This patch set introduces driver XDP for veth.
> Basically this is used in conjunction with redirect action of another XDP
> program.
> 
>   NIC -----------> veth===veth
>  (XDP) (redirect)        (XDP)
> 

I'm was playing with V7 on my testlab yesterday and I noticed one
fundamental issue.  You are not updating the "ifconfig" stats counters,
when in XDP mode.  This makes receive or send via XDP invisible to
sysadm/management tools.  This for-sure is going to cause confusion...

I took a closer look at other driver. The ixgbe driver is doing the
right thing.  Driver i40e have a bug, where RX/TX stats are swapped
getting (strange!).  The mlx5 driver is not updating the regular RX/TX
counters, but A LOT of other ethtool stats counters (which are the ones
I usually monitor when testing).

So, given other drivers also didn't get this right, we need to have a
discussion outside your/this patchset.  Thus, I don't want to
stop/stall this patchset, but this is something we need to fixup in a
followup patchset to other drivers as well.

Thus, I'm acking the patchset, but I request that we do a joint effort
of fixing this as followup patches.

Acked-by: Jesper Dangaard Brouer <[email-masked]>

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