[PATCH v2 2/5] perf jevents: Match on highest version of Arm json file available

[John Garry]

On 10/07/2023 15:19, James Clark wrote:

+


Hi James,

It would be good to cc some additional people and lists.

> Currently version and revision fields are masked out of the MIDR so

Do you mean variant and revision?

> there can only be one set of jsons per CPU. In a later commit multiple
> revisions of Neoverse N2 json files will be provided.
> 


> The highest valid version of json files should be used,

What exactly does that mean?

So it seems that you have CPUs with matching MIDR except variant and 
revision, but have different events, right?

Then to solve that are you saying that the highest version of the JSONs 
should used, upto and including the same CPU version (???) - correct?

The cover letter doesn't mention anything relevant :(

> but to make this
> work the mapfile has to be reverse sorted on the CPUID field so that the
> highest is found first.
> It's possible, but error prone, to do this
> manually so instead add an explicit sort into jevents.py. If the CPUID
> is a string then the rows are string sorted rather than numerically.
> 

Thanks,
John