Re: [dpdk-dev] [EXT] Re: [PATCH 1/3] mbuf: add Tx offloads for packet marking

["Ananyev, Konstantin" <konstantin.ananyev@intel.com>]

Hi Jerin,

> > > > I also share Olivier's concern about consuming 3 bits in ol_flags for that feature.
> > > > Can it probably be squeezed somehow?
> > > > Let say we reserve one flag that this information is present or not, and
> > > > re-use one of rx-only fields for store additional information (packet_type, or so).
> > > > Or might be some other approach.
> > >
> > > We are fine with this approach where we define one bit in Tx offloads for pkt
> > > marking and and 3 bits reused from Rx offload flags area.
> > >
> > > For example:
> > >
> > > @@ -186,10 +186,16 @@ extern "C" {
> > >
> > >  /* add new RX flags here, don't forget to update PKT_FIRST_FREE */
> > >
> > > +/* Reused Rx offload bits for Tx offloads */
> > > +#define PKT_X_TX_MARK_VLAN_DEI         (1ULL << 0)
> > > +#define PKT_X_TX_MARK_IP_DSCP          (1ULL << 1)
> > > +#define PKT_X_TX_MARK_IP_ECN           (1ULL << 2)
> > > +
> > >  #define PKT_FIRST_FREE (1ULL << 23)
> > > -#define PKT_LAST_FREE (1ULL << 40)
> > > +#define PKT_LAST_FREE (1ULL << 39)
> > >
> > >  /* add new TX flags here, don't forget to update PKT_LAST_FREE  */
> > > +#define PKT_TX_MARK_EN         (1ULL << 40)
> > >
> > > Is this fine ?
> >
> > Any thoughts on this approach which uses only 1 bit in Tx flags out of 18
> > and reuse unused Rx flag bits ?

My thought was not about re-defining the flags (I think it is better to keep them intact),
but adding a union for one of rx-only fields (packet_type/rss/timestamp).

> 
> + Techboard
> 
> There is a related thread going on
> http://mails.dpdk.org/archives/dev/2020-May/168810.html
> 
> If there is no consensus on email, then I would like to add this item
> to the next TB meeting.

Ok, I'll add that to tomorrow meeting agenda.
Konstantin