Re: [dpdk-dev] RFC: Enahancements to Rx adapter for DPDK 21.11

["Kundapura, Ganapati" <ganapati.kundapura@intel.com>]

Comments inlined

-----Original Message-----
From: Jerin Jacob <jerinjacobk@gmail.com> 
Sent: 28 July 2021 11:38
To: Kundapura, Ganapati <ganapati.kundapura@intel.com>
Cc: dpdk-dev <dev@dpdk.org>; Jayatheerthan, Jay <jay.jayatheerthan@intel.com>
Subject: Re: RFC: Enahancements to Rx adapter for DPDK 21.11

On Mon, Jul 26, 2021 at 6:37 PM Kundapura, Ganapati <ganapati.kundapura@intel.com> wrote:
>
> A gentle ping for comments.
>
> -----Original Message-----
> From: dev <dev-bounces@dpdk.org> On Behalf Of Kundapura, Ganapati
> Sent: 23 July 2021 12:33
> To: dpdk-dev <dev@dpdk.org>; Jerin Jacob <jerinjacobk@gmail.com>; 
> Jayatheerthan, Jay <jay.jayatheerthan@intel.com>
> Subject: [dpdk-dev] RFC: Enahancements to Rx adapter for DPDK 21.11
>
> Hi dpdk-dev,
>
> We would like to submit series of patches to Rx adapters that will enhance the configuration and performance.
> Please find the details below.
>
> (1) Configure Rx event buffer at run time
>     Add new api to configure the size of the Rx event buffer at run time.
>     This api allows setting the size of the event buffer at adapter level.

Since we can change ABI for 21.11, Not prefer to add a new API instead add a param to config structure.
Please send the deprecation notice for ABI change.

Config structure passed to rte_event_eth_rx_adapter_create() is of type rte_event_port_conf which
comes from event framework(rte_eventdev.h). 
Does it make sense to pass adapter event buffer size in rte_event_port_conf structure?

>
> (2) Change packet enqueue buffer in Rx adapter to circular buffer
>     Rx adapter uses memmove() to move unprocessed events to the begining
>     of packet enqueue buffer which consumes good amount of CPU cycles.

Looks good.


>
> (3) Add API to retrieve the Rx queue info
>     Rx queue info containinin  flags for handling received packets,
>     event queue identifier, schedular type, event priority,
>     polling frequence of the receive queue and flow identifier

Looks good. Please implement it as adaptor ops so that it can be adapter specific to support HW implementations.



>
> (4) Add adapter_stats cli to retrive Rx/Tx adapter stats and rxq info
>     This cli displays Rx and Tx adapter stats containing recieved packet count,
>     eventdev enqueue count, enqueue retry count, event buffer size, queue poll count,
>     transmitted packet count, packet dropped count, transmit fail count etc and rx queue info.

Generally, we don't entertain CLI in the library. You can add command-line arguments to app/test-eventdev to test this.

Adapter_stats is standalone application not part of library and it'll be in app/adapter_stats. 
>
> (5) Update Rx timestamp in mbuf using mbuf dynamic field
>     Add support to register timestamp dynamic field in mbuf
>     Update the timestamp in mbuf for each packet before eventdev 
> enqueue

Cool.

>
> We look forward to feedback on this proposal. Once we have initial feedback, patches will be submitted for review.
>
> Thanks,
> Ganapati