[RFC PATCH 09/19] mm/damon/sysfs: implement probes dir

SeongJae Park
2026-04-26T20:52:37Z

Implement sysfs directory that can be used by the users to install data
probes.

Signed-off-by: SeongJae Park <sj@kernel.org>
---
mm/damon/sysfs.c | 46 ++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 46 insertions(+)

diff --git a/mm/damon/sysfs.c b/mm/damon/sysfs.c
index d5863cc33d230..ccd19fc062f31 100644
--- a/mm/damon/sysfs.c
+++ b/mm/damon/sysfs.c
@@ -747,6 +747,35 @@ static const struct kobj_type damon_sysfs_intervals_ktype = {
.default_groups = damon_sysfs_intervals_groups,
};

+/*
+ * probes directory
+ */
+
+struct damon_sysfs_probes {
+ struct kobject kobj;
+};
+
+static struct damon_sysfs_probes *damon_sysfs_probes_alloc(void)
+{
+ return kzalloc_obj(struct damon_sysfs_probes);
+}
+
+static void damon_sysfs_probes_release(struct kobject *kobj)
+{
+ kfree(container_of(kobj, struct damon_sysfs_probes, kobj));
+}
+
+static struct attribute *damon_sysfs_probes_attrs[] = {
+ NULL,
+};
+ATTRIBUTE_GROUPS(damon_sysfs_probes);
+
+static const struct kobj_type damon_sysfs_probes_ktype = {
+ .release = damon_sysfs_probes_release,
+ .sysfs_ops = &kobj_sysfs_ops,
+ .default_groups = damon_sysfs_probes_groups,
+};
+
/*
* monitoring_attrs directory
*/
@@ -755,6 +784,7 @@ struct damon_sysfs_attrs {
struct kobject kobj;
struct damon_sysfs_intervals *intervals;
struct damon_sysfs_ul_range *nr_regions_range;
+ struct damon_sysfs_probes *probes;
};

static struct damon_sysfs_attrs *damon_sysfs_attrs_alloc(void)
@@ -771,6 +801,7 @@ static int damon_sysfs_attrs_add_dirs(struct damon_sysfs_attrs *attrs)
{
struct damon_sysfs_intervals *intervals;
struct damon_sysfs_ul_range *nr_regions_range;
+ struct damon_sysfs_probes *probes;
int err;

intervals = damon_sysfs_intervals_alloc(5000, 100000, 60000000);
@@ -799,8 +830,22 @@ static int damon_sysfs_attrs_add_dirs(struct damon_sysfs_attrs *attrs)
if (err)
goto put_nr_regions_intervals_out;
attrs->nr_regions_range = nr_regions_range;
+
+ probes = damon_sysfs_probes_alloc();
+ if (!probes) {
+ err = -ENOMEM;
+ goto put_nr_regions_intervals_out;
+ }
+ err = kobject_init_and_add(&probes->kobj,
+ &damon_sysfs_probes_ktype, &attrs->kobj, "probes");
+ if (err)
+ goto put_probes_out;
+ attrs->probes = probes;
return 0;

+put_probes_out:
+ kobject_put(&probes->kobj);
+ attrs->probes = NULL;
put_nr_regions_intervals_out:
kobject_put(&nr_regions_range->kobj);
attrs->nr_regions_range = NULL;
@@ -817,6 +862,7 @@ static void damon_sysfs_attrs_rm_dirs(struct damon_sysfs_attrs *attrs)
kobject_put(&attrs->nr_regions_range->kobj);
damon_sysfs_intervals_rm_dirs(attrs->intervals);
kobject_put(&attrs->intervals->kobj);
+ kobject_put(&attrs->probes->kobj);
}

static void damon_sysfs_attrs_release(struct kobject *kobj)
--
2.47.3