Re: [dpdk-dev] [PATCH v4 07/12] net/failsafe: support flow API

[Stephen Hemminger <stephen@networkplumber.org>]

On Thu, 1 Jun 2017 16:28:13 +0200
Gaëtan Rivet <gaetan.rivet@6wind.com> wrote:

> On Wed, May 31, 2017 at 08:21:39AM -0700, Stephen Hemminger wrote:
> > On Mon, 29 May 2017 15:42:19 +0200
> > Gaetan Rivet <gaetan.rivet@6wind.com> wrote:
> >   
> > > Signed-off-by: Gaetan Rivet <gaetan.rivet@6wind.com>
> > > Acked-by: Olga Shern <olgas@mellanox.com>
> > > ---
> > >  doc/guides/nics/features/failsafe.ini   |   1 +
> > >  drivers/net/failsafe/Makefile           |   1 +
> > >  drivers/net/failsafe/failsafe.c         |   1 +
> > >  drivers/net/failsafe/failsafe_eal.c     |   1 +
> > >  drivers/net/failsafe/failsafe_ether.c   |  70 +++++++++++
> > >  drivers/net/failsafe/failsafe_flow.c    | 216 ++++++++++++++++++++++++++++++++
> > >  drivers/net/failsafe/failsafe_ops.c     |  29 +++++
> > >  drivers/net/failsafe/failsafe_private.h |  18 +++
> > >  8 files changed, 337 insertions(+)
> > >  create mode 100644 drivers/net/failsafe/failsafe_flow.c  
> > 
> > How does this interact with typical case of VF and dumb virtual device?
> > The VF has flow API but dumb virtual device does not.
> >   
> 
> The fail-safe requires capabilities to be the same on all its slave. If
> a capability must be supported on the VF, then is should be as well on
> the synthetic path.
> 
> But the TAP PMD that can be used to capture traffic from a synthetic
> path supports rte_flow in the same capacity as other NICs.
> 
> > How does this work with late binding plugin? If VF arrives later is
> > the flow table reprogrammed to the VF?  
> 
> The fail-safe stores an internal representation of rte_flows. These are
> replayed in the same order upon plugin, so the flow table is
> reprogrammed in the same way to the VF.
> 

The synthetic path can't do flow direction in netvsc (and via tap). Therefore this whole
flow direction part is uninteresting for the use case of Hyper-V/Azure.