Re: [V1] app/testpmd: restore VXLAN-GPE support

[Thomas Monjalon <thomas@monjalon.net>]

22/07/2024 11:36, Ferruh Yigit:
> On 7/22/2024 8:10 AM, Minggang(Gavin) Li wrote:
> > From: Ferruh Yigit <ferruh.yigit@amd.com>
> >> On 7/17/2024 8:11 AM, Gavin Li wrote:
> >>> VXLAN-GPE support was removed from testpmd recently. Drivers which are
> >>> not migrated are still using VXLAN-GPE in tests.
> >>>
> >>> This commit is to restore the support for VXLAN-GPE in testpmd.
> >>>
> >>> Fixes: da118115d95c ("app/testpmd: support matching any VXLAN field")
> >>> Signed-off-by: Gavin Li <gavinl@nvidia.com>
> >>>
> >>
> >> Hi Gavin,
> >>
> >> The original patch was from you, right? What went wrong?
> > The remove of VXLAN-GPE from testpmd is too aggressive since there are
> > drivers which are not migrated are still using VXLAN-GPE. It's better to
> > keep it till the day to remove the RTE item of VXLAN-GPE from DPDK.
> >
> 
> Sorry, I was not clear enough maybe, I was asking more details on the
> problem?

I remember I was suggesting Gavin to remove testpmd code based on the old API.
And he realized it was too much agressive later.

> With a net/vxlan commit [1] in this release, (this commit is part of
> -rc1), VXLAN & VXLAN-GPE headers combined and VXLAN-GBP header added to
> this combined struct. VXLAN-GPE header is marked as deprecated.
> Testpmd is also updated to use new headers, that is the commit in the
> fixes tag of this patch.
> 
> But drivers using old, now depreciated, VXLAN structs won't able to use
> testpmd to test, so I agree, may be I merged the patch too early.

Yes, so this patch re-add testpmd code for the old API.

> As this patch was part of -rc1, I wonder why we didn't get any complaint
> about not able to test VXLAN-GPE?

Maybe it is tested only with mlx5.

> Btw, if we revert this patch, is there a way to test VXLAN-GBP? Because
> it only exists as part of new combined VXLAN struct?
> Instead of reverting the commit all together, is there way to keep old
> capability in testpmd, but add feature to test VXLAN-GBP?

It is not a complete revert, we keep GBP in the new API.

> And another issue is, there can still some users of the VXLAN-GPE header
> in the net library, perhaps that also deprecated immaturely.

It is just marked as deprecated.

> Can you please send a deprecation note for combining VXLAN headers and
> removing VXLAN-GPE in v24.11? Please CC all drivers implementing this
> flow pattern. This can be way to highlight the issue to driver
> maintainers and communicate the change with end users.

24.11 is probably too early.
I propose to keep it as deprecated for compatibility,
and maybe remove in one year?