Re: [dpdk-dev] [PATCH v4 1/4] eventdev: Add caps API and PMD callbacks for rte_event_eth_rx_adapter

[Jerin Jacob <jerin.jacob@caviumnetworks.com>]

-----Original Message-----
> Date: Sun, 24 Sep 2017 17:44:06 +0530
> From: "Rao, Nikhil" <nikhil.rao@intel.com>
> To: Jerin Jacob <jerin.jacob@caviumnetworks.com>
> CC: bruce.richardson@intel.com, gage.eads@intel.com, dev@dpdk.org,
>  thomas@monjalon.net, harry.van.haaren@intel.com, hemant.agrawal@nxp.com,
>  nipun.gupta@nxp.com, narender.vangati@intel.com,
>  erik.g.carrillo@intel.com, abhinandan.gujjar@intel.com,
>  santosh.shukla@caviumnetworks.com
> Subject: Re: [PATCH v4 1/4] eventdev: Add caps API and PMD callbacks for
>  rte_event_eth_rx_adapter
> User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101
>  Thunderbird/52.3.0
> 
> On 9/21/2017 9:16 PM, Jerin Jacob wrote:
> > -----Original Message-----
> > > Date: Fri, 22 Sep 2017 02:47:11 +0530
> > > From: Nikhil Rao <nikhil.rao@intel.com>
> > > To: jerin.jacob@caviumnetworks.com, bruce.richardson@intel.com
> > > CC: gage.eads@intel.com, dev@dpdk.org, thomas@monjalon.net,
> > >   harry.van.haaren@intel.com, hemant.agrawal@nxp.com, nipun.gupta@nxp.com,
> > >   narender.vangati@intel.com, erik.g.carrillo@intel.com,
> > >   abhinandan.gujjar@intel.com, santosh.shukla@caviumnetworks.com
> > > Subject: [PATCH v4 1/4] eventdev: Add caps API and PMD callbacks for
> > >   rte_event_eth_rx_adapter
> > > X-Mailer: git-send-email 2.7.4
> > > +/* Ethdev Rx adapter capability bitmap flags */
> > > +#define RTE_EVENT_ETH_RX_ADAPTER_CAP_INTERNAL_PORT	0x1
> > > +/**< Eventdev can send packets to ethdev using internal event port */
> > > +#define RTE_EVENT_ETH_RX_ADAPTER_CAP_SINGLE_EVENTQ	0x2
> > > +/**< Ethdev Rx queues can be connected to single event queue */
> > 
> > I think, Its is more of limitation. Since we are expressing it as
> > capability. How about changing it as RTE_EVENT_ETH_RX_ADAPTER_CAP_MULTI_EVENTQ
> > (same as exiting !RTE_EVENT_ETH_RX_ADAPTER_CAP_SINGLE_EVENTQ and SW driver has this capability)
> > i.e Ethdev Rx queues of single ethdev port can be connected to multiple
> > event queue.
> > 
> OK. I agree that the MULTI_EVENTQ is better suited to be expressed as a
> capability.
> 
> > > +#define RTE_EVENT_ETH_RX_ADAPTER_CAP_FLOW_ID		0x4
> > > +/**< Ethdev Rx adapter can set flow ID for event queue, if this flag
> > > + * is unset, the application needs to provide a flow id when adding
> > 
> > Looking at implementation, If I understand it correctly, it not application
> > "needs" to provide instead, it is application can provide. If so, I think,
> > making it as RTE_EVENT_ETH_RX_ADAPTER_CAP_SET_FLOW_ID or
> > RTE_EVENT_ETH_RX_ADAPTER_CAP_OVERRIDE_FLOW_ID makes more sense.
> > 
> If the FLOW_ID cap is not set, it is required for the application to provide
> it, else the application optionally can provide it but the feature of the
> application being able to provide (override) the flag should be a separate
> flag.
> 
> If it's only the override behavior that is required, we can rename the flag
> to OVERRIDE_FLOW_ID.

Yes. OVERRIDE_FLOW_ID behavior makes sense to me. Please update the
doxygen comments as well.