Re: [PATCH net] net: microchip: lan743x : bidirectional throughuput improvement

[<VishvambarPanth.S@microchip.com>]

On Thu, 2023-11-09 at 15:04 -0800, Jakub Kicinski wrote:
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> 
> On Thu, 9 Nov 2023 10:53:26 +0000 VishvambarPanth.S@microchip.com
> wrote:
> > Thanks for your feedback. I apologize for the delayed response.
> > 
> > The data presented in the patch description was aimed to convince a
> > reviewer with the visible impact of the performance boosts in both
> > x64
> > and ARM platforms. However, the main motivation behind the patch
> > was
> > not merely a "good-to-have" improvement but a solution to the
> > throughput issues reported by multiple customers in several
> > platforms.
> > We received lots of customer requests through our ticket site
> > system
> > urging us to address the performance issues on multiple kernel
> > versions
> > including LTS. While it's acknowledged that stable branch rules
> > typically do not consider performance fixes that are not documented
> > in
> > public Bugzilla, this performance enhancement is essential to many
> > of
> > our customers and their end users and we believe should therefore
> > be
> > considered for stable branch on the basis of it’s visible user
> > impact.
> > Few issues reported by our customers are mentioned below, even
> > though
> > these issues have existed for a long time, the data presented below
> > is
> > collected from the customer within last 3 months.
> > 
> > Customer-A using lan743x with Hisilicon- Kirin 990 processor in
> > 5.10
> > kernel, reported a mere ~300Mbps in Rx UDP. The fix significantly
> > improved the performance to ~900Mbps Rx  in their platform.
> > 
> > Customer-B using lan743x with v5.10 has an issue with Tx UDP being
> > only
> > 157Mbps in their platform. Including the fix in the patch boosts
> > the
> > performance to ~600Mbps in Tx UDP.
> > 
> > Customer-C using lan743x with ADAS Ref Design in v5.10 reported UDP
> > Tx/Rx to be 126/723 Mbps and the fix improved the performance to
> > 828/956 Mbps.
> > 
> > Customer-D using lan743x with Qcom 6490 with v5.4 wanted
> > improvements
> > for their platform from UDP Rx 200Mbps. The fix along with few
> > other
> > changes helped us to bring Rx perf to 800Mbps in customer’s
> > platform
> > 
> > This is a kind request for considering the acceptance of this patch
> > into the net branch, as it has a significant positive impact on
> > users
> > and does not have any adverse effects.
> 
> Thanks a lot for the details. Unfortunately after further
> consideration
> I can't accept this patch as a fix with clear conscience. The code
> has
> been this way for a long time, performance improvements should end up
> in new kernels and people who want to benefit from faster kernels
> should
> not be sticking to old LTS releases.
> 
> So please repost for net-next next week, when it's open again.

Hi Jakub,
Thanks for your inputs. Have submitted this patch to the net-next
branch.