mm/page_owner: add NUMA node filter

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.

Link: https://lore.kernel.org/20260707115411.1714314-3-zhen.ni@easystack.cn
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>
Cc: Brendan Jackman <jackmanb@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

0 files changed, 0 insertions, 0 deletions