Re: [PATCH v6 0/3] mm/page_owner: add filter infrastructure for print_mode and NUMA filtering

From: Michal Hocko

Date: Tue May 12 2026 - 05:01:52 EST


On Tue 12-05-26 16:16:36, zhen.ni wrote:
> ## Implementation Plan
>
> 1. Add per-fd filtering to page_owner file
> - Add .open/.release/.write callbacks
> - Each file descriptor has its own filter state
> - Write filter commands: "nid=0", "mode=stack_handle"
>
> 2. Provide user-space tool
> - Simple CLI: ./page_owner_tool --nid=0
> - Handle fd management internally
>
> ## User Experience
>
> Direct access (default: no filter):
> cat /sys/kernel/debug/page_owner
>
> With filtering:
> ./page_owner_tool --nid=0
> ./page_owner_tool --nid=0,2-3
> ./page_owner_tool --nid=0 --mode=stack_handle
>
> ## Benefits
>
> - Completely eliminates race condition
> - Per-fd isolation for concurrent access
> - Correct design for multi-consumer scenarios
>
> Does this approach look good to you?
>
> Please let me know if you have any suggestions or concerns.

Yes, this is what I had in mind.
Thanks for looking into that.

--
Michal Hocko
SUSE Labs