Re: [PATCH] cacheinfo: Introduce cache id

From: Borislav Petkov
Date: Fri Jul 01 2016 - 14:43:48 EST


On Fri, Jul 01, 2016 at 11:00:35AM -0700, Luck, Tony wrote:
> For CAT we only need the IDs to be unique at each level. Our tentative
> syntax for the schema file for CAT looks like this (for a theoretical
> system supporting CAT in both L2 and L3 with two L3 caches and eight L2 caches)
>
> L3:id0=fff;id1=ff0
> L2:id0=3;id1=c;id2=30;id3=c0;id4=3;id5=c;id6=30;id7=c0

So wouldn't it be straightforward and natural to do the following
nomenclature (which basically suggests itself):

ID<level>.<num>

?

So that the ID hierarchy above is:

ID3.0 ID3.1
ID2.0 ID2.1 ID2.2 ID2.3 ... ID2.7

I don't know if that's useful though.

I mean, we have that info in the path anyway:

/sys/devices/system/cpu/cpu0/cache/index3/id = 0xfff
...

and so on.

Whatever you do, as long as the nomenclature is documented somewhere,
say Documentation/x86/topology.txt, for example, we should be fine.

--
Regards/Gruss,
Boris.

SUSE Linux GmbH, GF: Felix ImendÃrffer, Jane Smithard, Graham Norton, HRB 21284 (AG NÃrnberg)
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