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

From: Jason Wang
Date: Thu Sep 28 2017 - 03:54:27 EST




On 2017å09æ28æ 13:02, Tom Herbert wrote:
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.

This could be done by using the API introduced in this series, I can try this in V2.

Thanks