Re: [PATCH v8 2/3] ethdev: add VXLAN last reserved field

[Thomas Monjalon <thomas@monjalon.net>]

12/06/2024 03:25, rongwei liu:
> From: Ferruh Yigit <ferruh.yigit@amd.com>
> > On 6/7/2024 3:02 PM, Rongwei Liu wrote:
> > > @@ -41,7 +41,10 @@ struct rte_vxlan_hdr {
> > >                       uint8_t    flags;    /**< Should be 8 (I flag). */
> > >                       uint8_t    rsvd0[3]; /**< Reserved. */
> > >                       uint8_t    vni[3];   /**< VXLAN identifier. */
> > > -                     uint8_t    rsvd1;    /**< Reserved. */
> > > +                     union {
> > > +                             uint8_t    rsvd1;        /**< Reserved. */
> > > +                             uint8_t    last_rsvd;    /**< Reserved. */
> > > +                     };
> > >
> > 
> > Is there a plan to remove 'rsvd1' in next ABI break release?
> > We can keep both, but I guess it is not logically necessary to keep it, to prevent
> > bloat by time, we can remove the old one.
> > If decided to remove, sending a 'deprecation.rst' update helps us to remember
> > doing it.
> > 
> I think it should. @NBU-Contact-Thomas Monjalon (EXTERNAL) @Andrew Rybchenko@Ori Kam what do you think?

From user perspective, there is no benefit in removing an aliased field,
except for simplicity.
The drawback is a potential API compatibility breakage.

We may mark it as deprecated in the comment and plan for removal in a long time, let's say 25.11?
Is there anyone against removing "rsvd1" in VXLAN header for compatibility purpose?