RE: Copy-pasted code should be updated

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

<snip>

> 
> Dear Intel PMD maintainers (CC: techboard),
> 
> I strongly recommend that you update the code you copy-pasted from the
> mempool library to your PMDs, so they reflect the new and improved
> mempool cache behavior [1]. When choosing to copy-paste code from a core
> library, you should feel obliged to keep your copied code matching the source
> code you copied it from!
> 
> Also, as reported in bug #1052, you forgot to copy-paste the instrumentation,
> thereby 1. making the mempool debug statistics invalid and 2. omitting the
> mempool accesses from the trace when using your PMDs. :-(
We are working on mempool APIs to expose the per core cache memory to PMD so that the buffers can be copied directly. We are planning to fix this duplication as part of that.

> 
> Alternatively, just remove the copy-pasted code and use the mempool
> library's API instead. ;-)
> 
> The direct re-arm code also contains copy-pasted mempool cache handling
> code - which was accepted with the argument that the same code was
> already copy-pasted elsewhere. I don't know if the direct re-arm code also
> needs updating... Authors of that patch (CC to this email), please coordinate
> with the PMD maintainers.
Direct-rearm patch is not accepted yet.

> 
> PS:  As noted in the 22.11-rc1 release notes, more changes to the mempool
> library [2] may be coming.
> 
> [1]:
> https://patches.dpdk.org/project/dpdk/patch/20221007104450.2567961-1-
> andrew.rybchenko@oktetlabs.ru/
> 
> [2]: https://patches.dpdk.org/project/dpdk/list/?series=25063
> 
> -Morten