Re: [PATCH net-next 0/3] support changing steering policies in tuntap

[Tom Herbert]

On Wed, Sep 27, 2017 at 4:25 PM, Willem de Bruijn
<willemdebruijn.kernel@xxxxxxxxx> wrote:
>>> In the future, both simple and sophisticated policy like RSS or other guest
>>> driven steering policies could be done on top.
>>
>> IMHO there should be a more practical example before adding all this
>> indirection. And it would be nice to understand why this queue selection
>> needs to be tun specific.
>
> I was thinking the same and this reminds me of the various strategies
> implemented in packet fanout. tun_cpu_select_queue is analogous to
> fanout_demux_cpu though it is tun-specific in that it requires tun->numqueues.
>
> Fanout accrued various strategies until it gained an eBPF variant. Just
> supporting BPF is probably sufficient here, too.

+1, in addition to packet fanout, we have SO_REUSEPORT with BPF, RPS,
RFS, etc. It would be nice if existing packet steering mechanisms
could be leveraged for tun.