[PATCH 1/3] mm/page_owner: add filter infrastructure

Zhen Ni
2026-04-17T16:02:17Z

Add data structure for page_owner filtering functionality and create
debugfs directory for filter controls.

This adds:
- struct page_owner_filter with compact and nid fields
- Static owner_filter instance initialized with default values
- page_owner_filter debugfs directory

The filter infrastructure will be used to add compact mode and NUMA node
filtering capabilities in subsequent commits.

Signed-off-by: Zhen Ni <zhen.ni@easystack.cn>
---
mm/page_owner.c | 15 ++++++++++++++-
1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/mm/page_owner.c b/mm/page_owner.c
index 8178e0be557f..6811439bf9e4 100644
--- a/mm/page_owner.c
+++ b/mm/page_owner.c
@@ -54,6 +54,16 @@ struct stack_print_ctx {
u8 flags;
};

+struct page_owner_filter {
+ bool compact;
+ int nid;
+};
+
+static struct page_owner_filter owner_filter = {
+ .compact = false,
+ .nid = -1,
+};
+
static bool page_owner_enabled __initdata;
DEFINE_STATIC_KEY_FALSE(page_owner_inited);

@@ -973,7 +983,7 @@ DEFINE_SIMPLE_ATTRIBUTE(page_owner_threshold_fops, &page_owner_threshold_get,

static int __init pageowner_init(void)
{
- struct dentry *dir;
+ struct dentry *dir, *filter_dir;

if (!static_branch_unlikely(&page_owner_inited)) {
pr_info("page_owner is disabled\n");
@@ -981,6 +991,9 @@ static int __init pageowner_init(void)
}

debugfs_create_file("page_owner", 0400, NULL, NULL, &page_owner_fops);
+
+ filter_dir = debugfs_create_dir("page_owner_filter", NULL);
+
dir = debugfs_create_dir("page_owner_stacks", NULL);
debugfs_create_file("show_stacks", 0400, dir,
(void *)(STACK_PRINT_FLAG_STACK |
--
2.20.1