Re: [dpdk-dev] [PATCH v3 00/14] acl: introduce AVX512 classify methods

[David Marchand <david.marchand@redhat.com>]

On Mon, Oct 5, 2020 at 9:44 PM Konstantin Ananyev
<konstantin.ananyev@intel.com> wrote:
>
> These patch series introduce support of AVX512 specific classify
> implementation for ACL library.
> It adds two new algorithms:
>  - RTE_ACL_CLASSIFY_AVX512X16 - can process up to 16 flows in parallel.
>    It uses 256-bit width instructions/registers only
>    (to avoid frequency level change).
>    On my SKX box test-acl shows ~15-30% improvement
>    (depending on rule-set and input burst size)
>    when switching from AVX2 to AVX512X16 classify algorithms.
>  - RTE_ACL_CLASSIFY_AVX512X32 - can process up to 32 flows in parallel.
>    It uses 512-bit width instructions/registers and provides higher
>    performance then AVX512X16, but can cause frequency level change.
>    On my SKX box test-acl shows ~50-70% improvement
>    (depending on rule-set and input burst size)
>    when switching from AVX2 to AVX512X32 classify algorithms.
>    ICX and CLX testing showed similar level of speedup.
>
> Current AVX512 classify implementation is only supported on x86_64.
> Note that this series introduce a formal ABI incompatibility

The only API change I can see is in rte_acl_classify_alg() new error
code but I don't think we need an announcement for this.
As for ABI, we are breaking it in this release, so I see no pb.


> with previous versions of ACL library.
>
> v2 -> v3:
>   Fix checkpatch warnings
>   Split AVX512 algorithm into two and deduplicate common code

Patch 7 still references a RTE_MACHINE_CPUFLAG flag.
Can you rework now that those flags have been dropped?

Thanks.


-- 
David Marchand