Re: [PATCH net-next V2 1/3] tun: abstract flow steering logic

[Jason Wang]

On 2017å11æ02æ 11:45, Michael S. Tsirkin wrote:
> On Thu, Nov 02, 2017 at 11:43:48AM +0800, Jason Wang wrote:
> > On 2017å11æ02æ 09:11, Willem de Bruijn wrote:
> > > On Tue, Oct 31, 2017 at 7:32 PM, Jason Wang <jasowang@xxxxxxxxxx> wrote:
> > > > tun now use flow caches based automatic queue steering method. This
> > > > may not suffice all user cases. To extend it to be able to use more
> > > > flow steering policy, this patch abstracts flow steering logic into
> > > > tun_steering_ops, then we can declare and use different methods in
> > > > the future.
> > > > Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx>
> > > > ---
> > > >    drivers/net/tun.c | 85 +++++++++++++++++++++++++++++++++++++++++--------------
> > > >    1 file changed, 63 insertions(+), 22 deletions(-)
> > > >
> > > > diff --git a/drivers/net/tun.c b/drivers/net/tun.c
> > > > index ea29da9..bff6259 100644
> > > The previous RFC enabled support for multiple pluggable steering
> > > policies. But as all can be implemented in BPF and we only plan to
> > > support an eBPF policy besides the legacy one, this patch is no longer
> > > needed. We can save a few indirect function calls.
> > But we should at least support two kinds of steering policy, so this is
> > still needed?
> >
> > And I'm not quite sure we can implement all kinds of policies through BPF
> > e.g RSS or we may want to offload the queue selection to underlayer switch
> > or nic .
> >
> > Thanks
> I think a simple if condition is preferable for now, too. Let's wait
> until we get some 3/4 of these.

That's a solution but we may need if in at least four places. If this is 
ok, I will do it in next version.

Thanks