RE: [RFC 1/2] eal: add llc aware functions

["Varghese, Vipin" <Vipin.Varghese@amd.com>]

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> >        Some SOCs may only show upper-level caches here, therefore
> > cannot be use blindly without knowing the SOC.
> >
> > Can you please help us understand
> >
>
> For instance, in Neoverse N1 can disable the use of SLC as LLC (a BIOS setting)
> If SLC is not used as LLC, then your script would report the unified L2 as an LLC.

Does `disabling SLC as LLC` disable L3? I think not, and what you are implying is the ` ls -d /sys/bus/cpu/devices/cpu%u/cache/index[0-9] | sort -r …… `  will return index2 and not index3. Is this the understanding?


> I don't think that's what you are interested in.
My intention as shared is to `whether BIOS setting for CPU NUMA is enabled or not, I would like to allow the end customer get the core complexes (tile) which are under one group`.
So, if the `Last Level Cache` is L3 or L2 seen by OS, API allows the end user to get DPDK lcores sharing the last level cache.

But as per the earlier communication, specific SoC does not behave when some setting are done different. For AMD SoC case we are trying to help end user with right setting with tuning guides as pointed by ` 12. How to get best performance on AMD platform — Data Plane Development Kit 24.11.0-rc0 documentation (dpdk.org)<https://doc.dpdk.org/guides/linux_gsg/amd_platform.html>`

Can you please confirm if such tuning guides or recommended settings are shared ? If not, can you please allow me to setup a technical call to sync on the same?

>
> > 1. if there are specific SoC which do not populate the information at
> > all? If yes are they in DTS?
>
> This information is populated correctly for all SOCs, comment was on the
> script.

Please note, I am not running any script. The command LCORE_GET_LLC is executed using C function `open`. As per suggestion of Stephen we have replied we will change to C function logic to get details.
Hope there is no longer confusion on this?



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