Subject: Re: [PATCH net] xsk: Bring back busy polling support

From: Jakub Kicinski <[email-masked]>
Date: Thu, 9 Jan 2025 08:43:01 -0800

On Thu, 9 Jan 2025 16:22:16 +0100 Magnus Karlsson wrote:
> > Confirmed by running a busy-polling AF_XDP socket
> > (github.com/fomichev/xskrtt) on mlx5 and looking at BusyPollRxPackets
> > from /proc/net/netstat.  
> 
> Thanks Stanislav for finding and fixing this. As a bonus, the
> resulting code is much nicer too.
> 
> I just took a look at the Intel drivers and some of our drivers have
> not been converted to use netif_queue_set_napi() yet. Just ice, e1000,
> and e1000e use it. But that is on us to fix.

Yup, on a quick look yesterday I think I spotted a few embedded
drivers (stmmac, tsnep, dpaa2), nfp and virtio_net which don't seem 
to link the NAPI to queues. But I can't think of a better fix, and
updating those drivers to link NAPI to queues will be generally
beneficial, so in case someone else applies this:

Reviewed-by: Jakub Kicinski <[email-masked]>