On Thu, Jun 1, 2023 at 11:31 AM Ori Kam <or...@nvidia.com> wrote: > > > > > -----Original Message----- > > From: David Marchand <david.march...@redhat.com> > > Sent: Thursday, June 1, 2023 11:48 AM > > > > On Wed, May 24, 2023 at 8:44 PM David Marchand > > <david.march...@redhat.com> wrote: > > > On Wed, May 24, 2023 at 6:00 PM Ori Kam <or...@nvidia.com> wrote: > > > > > As reported by Ilya [1], unconditionally calling > > > > > rte_flow_get_restore_info() impacts an application performance for > > drivers > > > > > that do not provide this ops. > > > > > It could also impact processing of packets that require no call to > > > > > rte_flow_get_restore_info() at all. > > > > > > > > > > Advertise in mbuf (via a dynamic flag) whether the driver has more > > > > > metadata to provide via rte_flow_get_restore_info(). > > > > > The application can then call it only when required. > > > > > > > > > > Link: http://inbox.dpdk.org/dev/5248c2ca-f2a6-3fb0-38b8- > > > > > 7f659bfa4...@ovn.org/ > > > > > Signed-off-by: David Marchand <david.march...@redhat.com> > > > > > --- > > > > > Note: I did not test this RFC patch yet but I hope we can resume and > > > > > maybe conclude on the discussion for the tunnel offloading API. > > > > > > > > > > > > > I think your approach has a good base but what happens if > > > > it is not relevant for all flows? In this case your solution will not > > > > work. > > > > > > Sorry, I am not following. > > > Could you develop? > > > > I still don't get your comment, could you give an example/usecase > > where this approach can't work? > > Thanks. > > > I'm think of a use case that some flows have the restore info, while > other don't for example, we get arp packets or some packets that > are not tunneled, and we also get tunneled packets. > > Or for example PMD supports this flag but the application didn't offload such > a rule yet.
Again, maybe I missed something, but my proposal is for a *per packet* report from the driver. I am not for a global driver capability, if this is what you have in mind. > > In those cases application will be slow even if he didn't offload the rules, > I assume we can say that if application wants to use this he should know > that other packets will have some performance issues. > > From my point of view if application requested the tunnel offload it should > always check this function. With a per packet flag, the application only calls restore_info when such tunnel offload rules have been requested, and only for packets that require it. -- David Marchand
