Re: [PATCH v2 3/3] x86/resctrl: Replace open code cacheinfo search in rdtgroup_cbm_to_size()

[Borislav Petkov]

On Wed, Jun 05, 2024 at 09:14:27AM -0700, Tony Luck wrote:
> Use get_cpu_cacheinfo_level() instead of open coded search.
> 
> Signed-off-by: Tony Luck <tony.luck@xxxxxxxxx>
> Reviewed-by: Reinette Chatre <reinette.chatre@xxxxxxxxx>
> ---
>  arch/x86/kernel/cpu/resctrl/rdtgroup.c | 14 +++++---------
>  1 file changed, 5 insertions(+), 9 deletions(-)
> 
> diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> index 02f213f1c51c..cb68a121dabb 100644
> --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> @@ -1450,18 +1450,14 @@ static ssize_t rdtgroup_mode_write(struct kernfs_open_file *of,
>  unsigned int rdtgroup_cbm_to_size(struct rdt_resource *r,
>  				  struct rdt_domain *d, unsigned long cbm)
>  {
> -	struct cpu_cacheinfo *ci;
>  	unsigned int size = 0;
> -	int num_b, i;
> +	struct cacheinfo *ci;
> +	int num_b;
>  
>  	num_b = bitmap_weight(&cbm, r->cache.cbm_len);
> -	ci = get_cpu_cacheinfo(cpumask_any(&d->cpu_mask));
> -	for (i = 0; i < ci->num_leaves; i++) {
> -		if (ci->info_list[i].level == r->cache_level) {
> -			size = ci->info_list[i].size / r->cache.cbm_len * num_b;
> -			break;
> -		}
> -	}
> +	ci = get_cpu_cacheinfo_level(cpumask_any(&d->cpu_mask), r->cache_level);
> +	if (ci)
> +		size = ci->size / r->cache.cbm_len * num_b;
>  
>  	return size;
>  }
> -- 

Those last two patches can be a single one which replaces open-coded
cacheinfo search in resctrl.

Or is there any particular reason for them to be separate?

Because it is a single logical change...

Thx.

-- 
Regards/Gruss,
    Boris.

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