Re: [PATCH v10 1/3] mm: Add node_to_range lookup facility to numa_memblks

[Borislav Petkov <bp@alien8.de>]

On Fri, Aug 01, 2025 at 06:20:27PM +0100, shiju.jose@huawei.com wrote:
> From: Shiju Jose <shiju.jose@huawei.com>
> 
> Lookup facility to retrieve memory phys lowest continuous range for
			
A commit message is not code. Please write it for humans.

> a NUMA node is required in the numa_memblks for the ACPI RAS2 memory
> scrub use case.
> 
> Suggested-by: Jonathan Cameron <jonathan.cameron@huawei.com>
> Signed-off-by: Shiju Jose <shiju.jose@huawei.com>
> ---
>  include/linux/numa.h         | 10 ++++++++++
>  include/linux/numa_memblks.h |  2 ++
>  mm/numa.c                    | 10 ++++++++++
>  mm/numa_memblks.c            | 23 +++++++++++++++++++++++
>  4 files changed, 45 insertions(+)

...

> +static int nid_to_meminfo(struct numa_meminfo *mi, int nid, u64 *start, u64 *end)

This function name sounds like it converts a node ID to meminfo. But it
doesn't do that.

> +{
> +	int i;
> +
> +	if (!numa_valid_node(nid))
> +		return -EINVAL;
> +
> +	for (i = 0; i < mi->nr_blks; i++) {
> +		if (mi->blk[i].nid == nid) {
> +			*start = mi->blk[i].start;
> +			*end = mi->blk[i].end;

It looks like it returns the start and end range of a node ID.

> +			return 0;
> +		}
> +	}
> +
> +	return -ENODEV;
> +}
> +
> +int node_to_phys_lowest_continuous_range(int nid, u64 *start, u64 *end)
> +{
> +	return nid_to_meminfo(&numa_meminfo, nid, start, end);

Where is the "lowest" thing here?

And where is the "continuous" thing?

This thing simply hides the struct numa_meminfo from the exported interface.

-- 
Regards/Gruss,
    Boris.

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