[dpdk-dev] [PATCH v6 1/6] ethdev: introduce Rx buffer split

[Slava Ovsiienko]

Hi, 

Evening update:
- addressed code comments
- provided the union of segmentation description  with dedicated feature structures according Jerin's proposal
- added the reporting of split limitation

With best regards, Slava

> -----Original Message-----
> From: Andrew Rybchenko <andrew.rybchenko at oktetlabs.ru>
> Sent: Thursday, October 15, 2020 16:07
> To: NBU-Contact-Thomas Monjalon <thomas at monjalon.net>; Ferruh Yigit
> <ferruh.yigit at intel.com>; Jerin Jacob <jerinjacobk at gmail.com>; Slava
> Ovsiienko <viacheslavo at nvidia.com>; Andrew Rybchenko
> <arybchenko at solarflare.com>
> Cc: dpdk-dev <dev at dpdk.org>; Stephen Hemminger
> <stephen at networkplumber.org>; Olivier Matz <olivier.matz at 6wind.com>;
> Maxime Coquelin <maxime.coquelin at redhat.com>; David Marchand
> <david.marchand at redhat.com>
> Subject: Re: [dpdk-dev] [PATCH v6 1/6] ethdev: introduce Rx buffer split
> 
> On 10/15/20 3:49 PM, Thomas Monjalon wrote:
> > 15/10/2020 13:49, Slava Ovsiienko:
> >> From: Ferruh Yigit <ferruh.yigit at intel.com>
> >>> On 10/15/2020 12:26 PM, Jerin Jacob wrote:
> >>>
> >>> <...>
> >>>
> >>>>>>>> If we see some of the features of such kind or other PMDs
> >>>>>>>> adopts the split feature - we'll try to find the common root
> >>>>>>>> and consider the way how
> >>>>>> to report it.
> >>>>>>>
> >>>>>>> My only concern with that approach will be ABI break again if
> >>>>>>> something needs to exposed over rte_eth_dev_info().
> >>>>>
> >>>>> Let's reserve the pointer to struct rte_eth_rxseg_limitations in
> >>>>> the rte_eth_dev_info to avoid ABI break?
> >>>>
> >>>> Works for me. If we add an additional reserved field.
> >>>>
> >>>> Due to RC1 time constraint, I am OK to leave it as a reserved filed
> >>>> and fill meat when it is required if other ethdev maintainers are OK.
> >>>> I will be required for feature complete.
> >>>>
> >>>
> >>> Sounds good to me.
> >
> > OK for me.
> 
> OK as well, but I dislike the idea with pointer in dev_info.
> It sounds like it breaks existing practice.
> We should either reserve enough space or simply add dedicated API call to
> report Rx seg capabilities.
> 
> >
> >> OK, let's introduce the pointer in the rte_eth_dev_info and define
> >> struct rte_eth_rxseg_limitations as experimental.
> >> Will it be allowed to update this one later (after 20.11)?
> >> Is ABI break is allowed for the case?
> >
> > If it is experimental, you can change it at anytime.
> >
> > Ideally, we could try to have a first version of the limitations
> > during 20.11-rc2.
> 
> Yes, please.