RE: [dpdk-dev] Minutes of Technical Board Meeting, 2021-Oct-27

[Honnappa Nagarahalli <Honnappa.Nagarahalli@arm.com>]

<snip>

> 
> 
> 
> Hi Jerin,
> 
> > > Minutes of Technical Board Meeting, 2021-Oct-27
> > >
> > > Members Attending
> > > ---------------------------
> > > -Aaron
> > > -Ferruh
> > > -Hemant
> > > -Honnappa
> > > -Jerin
> > > -Kevin
> > > -Konstantin (Chair)
> > > -Maxime
> > > -Stephen
> > > -Thomas
> > >
> > > NOTE: The technical board meetings every second Wednesday at
> > > https://meet.jit.si/DPDK at 3 pm UTC.
> > > Meetings are public, and DPDK community members are welcome to
> attend.
> > >
> > > NOTE: Next meeting will be on Wednesday 2021-Nov-03 @3pm UTC, and
> > > will be chaired by Maxime.
> > >
> > >
> > > GPUDEV library / DWA library inclusion
> > >
> http://inbox.dpdk.org/dev/DM6PR12MB41079FAE6B5DA35102B1BBFACDB7
> 9@DM6PR12MB4107.namprd12.prod.outlook.com/
> > >   http://mails.dpdk.org/archives/dev/2021-October/226070.html
> > >
> > >
> > > 1. GPU dev
> > > =========
> > >
> > > Pros:
> > > - simple and clean API
> > > - address particular needs:
> > >     - external (GPU) memory management within DPDK
> > >     - provides generic framework for CPU-GPU-NIC interaction
> > > - Not specific to any particular workload
> > > - GPU program creation/upload is out of scope for this framework
> > >
> > > Concerns:
> > > -  Framework is specific for just one particular accelerator class (GPU)
> > >    If we go that way, does it mean we'll need a separate library/API for
> each
> > >    new HW device class (FPGA, etc.)?
> > >
> > > 2. DWA dev
> > > ==========
> > >
> > > Pros:
> > > - HW neutral abstraction for accelerator communication
> > > - HW neutral abstraction for workload definitions (via profile)
> > > - Ability to chain services provided by HW (chain multiple profiles)
> > > - Sounds like really good approach for SoCs
> > >
> > > Concerns:
> > > - Not easy to agree/define mandatory/optional features for each
> > > particular profile
> > > - User limited to particular already implemented profiles (longer
> > > time to market, etc.)
> > > - Richness of features might cause overcomplication in both internal
> > >   design/implementation and public API
> > >
> > > Conclusion
> > > =========
> > >
> > > At that stage it is really hard to predict which approach will be more
> successful.
> > > As both paths can co-exist within DPDK:
> > >
> > > 1) Go ahead with both approaches as experimental lib/drivers inside
> > > DPDK
> >
> > Now that there is approval from TB.
> >
> > I would like to ask, Is anyone planning to review the specification
> > header file [1]?
> >
> > There was a comment to remove the TLV length. I will do that next
> > version with implementation.
> >
> > Identified the following set of work for this.
> >
> > 1) Common code at lib/dwa/
> > 2) Marvell DPU based driver at drivers/dwa/cnxk/
> > 3) Test application at app/test-dwa/
> > 4) It is possible to have an SW driver(To allow non-specialized HW to
> > use the framework) for this by:
> > a) Emulate DWA HW as a separate DPDK process
> > b) Add drivers/dwa/sw/ and use memif driver so to create a
> > communication channel between emulated DWA HW process and DPDK
> > application.
> > c) Add drivers/dwa/sw/profiles//l3fwd - To implement l3fwd profile
> > using DPDK libraries for SW driver.
> >
> > I think, Item (4) aka SW drivers as useful(We don't need to implement
> > for all profiles, I think, just for  l3fwd it make sense to add, to
> > allow to use of the framework in just SW mode).
> > Is there any opinion on adding item (4) in DPDK? I saw mixed opinions
> > earlier on this. I would like to understand, Is there any objection to
> > doing
> > item(4) in DPDK as it needs a good amount of work and  I don't want to
> > do throw it away if the community doesn't like this.
> > Any opinion?
> 
> I'd say (4) is a good thing to have.
> Will allow people to try/test DWA approach and framework itself without
> access to specific HW.
Agree in general it is good as a standard of the expected behavior. But, it might be difficult/complex to implement all the profiles. For ex: L1 processing for 5G.

> 
> > [1]
> > http://mails.dpdk.org/archives/dev/2021-October/226070.html
> >
> >
> > > 2) Re-evaluate both approaches in one year time
> > > 3) Both should follow usual DPDK policy for new lib/device classes:
> > >     generic framework plus at least one driver implementation
> > > 4) Both should be usable with open-source tools
> > >     (no exclusive dependency on third-party proprietary SW).
> > >
> > >