[PATCH 02/33] drivers: base: cacheinfo: Add helper to find the cache size from cpu+level

[Dave Martin]

Hi,

On Wed, Aug 27, 2025 at 06:11:43PM +0100, James Morse wrote:
> Hi Dave,
> 
> On 27/08/2025 11:46, Dave Martin wrote:
> > Hi,
> > 
> > On Fri, Aug 22, 2025 at 03:29:43PM +0000, James Morse wrote:
> >> MPAM needs to know the size of a cache associated with a particular CPU.
> >> The DT/ACPI agnostic way of doing this is to ask cacheinfo.
> >>
> >> Add a helper to do this.
> 
> >> diff --git a/include/linux/cacheinfo.h b/include/linux/cacheinfo.h

[...]

> >> +static inline unsigned int get_cpu_cacheinfo_size(int cpu, int level)
> >> +{
> >> +	struct cacheinfo *ci = get_cpu_cacheinfo_level(cpu, level);
> >> +
> >> +	return ci ? ci->size : 0;
> >> +}
> >> +
> > 
> > Orphaned function?
> > 
> > Can fs/resctrl/rdtgroup.c:rdtgroup_cbm_to_size() be ported to use this?
> > If so, this wouldn't just be dead code in this series.
> 
> Ah - I thought the MPAM driver was pulling this value in, but its the resctrl glue code.
> I was trying to reduce the number of trees this touches - its probably best to kick this
> into the next series that adds the resctrl code as its pretty trivial.
> 
> 
> Thanks,
> 
> James
> 

Fair enough.

Cheers
---Dave