Re: [PATCH v12 2/4] mm/page_owner: add NUMA node filter

["Vlastimil Babka (SUSE)" <vbabka@kernel.org>]

On 7/7/26 13:54, Zhen Ni wrote:
> Add NUMA node filtering functionality to page_owner to allow filtering
> pages by specific NUMA node(s). This is useful for NUMA-aware memory
> allocation analysis and debugging.
> 
> The filter supports flexible input formats:
> - Single node: nid=0
> - Multiple nodes: nid=0,2,3
> - Node range: nid=0-3
> - Mixed format: nid=0,2-4,7
> 
> Example usage:
>   # Using the page_owner_filter tool (recommended)
>   ./page_owner_filter -n 0-3
>   ./page_owner_filter -m stack_handle -n 0,2-4,7
> 
> The implementation uses per-file-descriptor filter state stored in
> file->private_data, allowing each opener to have independent filter
> configuration. It uses nodemask_t for efficient multi-node filtering and
> nodelist_parse() for flexible input parsing. Node validity is verified
> using nodes_subset() to reject nodes without memory.
> 
> Signed-off-by: Zhen Ni <zhen.ni@easystack.cn>
> Tested-by: Zi Yan <ziy@nvidia.com>
> Acked-by: Zi Yan <ziy@nvidia.com>

Reviewed-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>