Re: [PATCH v6 00/40] arm_mpam: Add KVM/arm64 and resctrl glue code

[Ben Horgan]

Hi Jesse,

On 3/17/26 00:25, Jesse Chick wrote:
> Hi Ben,
> 
> 
>> Thanks for all the reviewing and testing so far. Just a bit more to get this
>> over the line.
> 
> 
> I tested this patch series, specifically L3 CPOR, on an Ampere
> implementation with common benchmarking tools (lmbench, multichase).
> 
> 
>> Generally the resctrl glue code works by picking what MPAM features it can expose
>> from the MPAM drive, then configuring the structs that back the resctrl helpers.
>> If your platform is sufficiently Xeon shaped, you should be able to get L2/L3 CPOR
>> bitmaps exposed via resctrl. CSU counters work if they are on/after the L3. MBWU
>> counters are considerably more hairy, and depend on hueristics around the topology,
>> and a bunch of stuff trying to emulate ABMC.
> 
> 
> The observed latency in increasingly large R/W operations scaled as
> expected across various numbers of competing processes and cache
> portions. The distinct jumps in latency as successive cache level
> capacities were exceeded indicates that (a) L3 CPOR is configurable from
> user space via the resctrl interface as described in this series and (b)
> that the feature itself is working correctly.
> 
> For the series:
> 
> Tested-by: Jesse Chick <jessechick@xxxxxxxxxxxxxxxxxxxxxx>

Thanks for the testing and description.

Ben

> 
> Thanks,
> Jesse
> 
>