Re: [PATCH v2 05/18] x86/resctrl: Allow RMID allocation to be scoped by CLOSID

[Reinette Chatre]

Hi James,

On 1/13/2023 9:54 AM, James Morse wrote:
> MPAMs RMID values are not unique unless the CLOSID is considered as well.
> 
> alloc_rmid() expects the RMID to be an independent number.
> 
> Pass the CLOSID in to alloc_rmid(). Use this to compare indexes when
> allocating. If the CLOSID is not relevant to the index, this ends up
> comparing the free RMID with itself, and the first free entry will be
> used. With MPAM the CLOSID is included in the index, so this becomes a
> walk of the free RMID entries, until one that matches the supplied
> CLOSID is found.
> 
> Tested-by: Shaopeng Tan <tan.shaopeng@xxxxxxxxxxx>
> Signed-off-by: James Morse <james.morse@xxxxxxx>

...

>  /*
> - * As of now the RMIDs allocation is global.
> + * As of now the RMIDs allocation is the same in each domain.

Could you please elaborate what is meant/intended with this change
(global vs per domain)? From the changelog a comment that RMID
allocation is the same in each resource group for MPAM may be
expected but per domain is not clear to me.

Reinette