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

[Jerin Jacob <jerinjacobk@gmail.com>]

> > > 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 ?

+ 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.