Re: [PATCH v5 06/10] x86/resctrl: Replace "msr" in monitoring data identifiers

[Reinette Chatre]

Hi Chenyu,

On 7/1/26 6:46 AM, Chen Yu wrote:
> Monitoring counter values are currently obtained via MSR and many
> identifiers involved in processing these values contain "msr"
> as part of their names, for example "prev_msr" and "msr_val".
> 
> The ERDT ACPI table describes MMIO registers for monitoring data
> access. Rename "msr"-based identifiers to be interface-agnostic
> to support their upcoming use for MMIO-read values.

Are any of the identifiers renamed by this patch actually used by
the MMIO reading code introduced by this series?

> 
> No functional change.
> 
> Reviewed-by: Thomas Gleixner <tglx@xxxxxxxxxx>
> Tested-by: Hongyu Ning <hongyu.ning@xxxxxxxxxxxxxxx>
> Signed-off-by: Chen Yu <yu.c.chen@xxxxxxxxx>
> ---

...

> diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
> index 3dab05c38003..6eb0fdea6b63 100644
> --- a/arch/x86/kernel/cpu/resctrl/internal.h
> +++ b/arch/x86/kernel/cpu/resctrl/internal.h
> @@ -52,13 +52,13 @@ struct erdt_domain_info {
>  /**
>   * struct arch_mbm_state - values used to compute resctrl_arch_rmid_read()s
>   *			   return value.
> - * @chunks:	Total data moved (multiply by rdt_group.mon_scale to get bytes)
> - * @prev_msr:	Value of IA32_QM_CTR last time it was read for the RMID used to
> - *		find this struct.
> + * @chunks:		Total data moved (multiply by rdt_group.mon_scale to get bytes)

One renaming that does seem warranted is mon_scale that is a per-resource value that
currently claims to "cqm counter * mon_scale = occupancy in bytes" but this implementation
does not use it and instead uses a value private to ERDT.

Reinette