[RFC PATCH 10/17] mm/damon/sysfs: create probe preps directory

From: SJ Park

Date: Sat Jul 25 2026 - 17:07:00 EST


Create probe preps directory when the probe directory is generated.

Signed-off-by: SJ Park <sj@xxxxxxxxxx>
---
mm/damon/sysfs.c | 48 ++++++++++++++++++++++++++++++++++++++++++------
1 file changed, 42 insertions(+), 6 deletions(-)

diff --git a/mm/damon/sysfs.c b/mm/damon/sysfs.c
index 7b971bfd1169f..6d3ed80fb2eb1 100644
--- a/mm/damon/sysfs.c
+++ b/mm/damon/sysfs.c
@@ -759,6 +759,16 @@ struct damon_sysfs_preps {
int nr;
};

+static struct damon_sysfs_preps *damon_sysfs_preps_alloc(void)
+{
+ return kzalloc_obj(struct damon_sysfs_preps);
+}
+
+static void damon_sysfs_preps_rm_dirs(struct damon_sysfs_preps *preps)
+{
+ preps->nr = 0;
+}
+
static int damon_sysfs_preps_add_dirs(struct damon_sysfs_preps *preps,
int nr_preps)
{
@@ -1138,6 +1148,7 @@ static const struct kobj_type damon_sysfs_filters_ktype = {
struct damon_sysfs_probe {
struct kobject kobj;
unsigned int weight;
+ struct damon_sysfs_preps *preps;
struct damon_sysfs_filters *filters;
};

@@ -1148,25 +1159,50 @@ static struct damon_sysfs_probe *damon_sysfs_probe_alloc(void)

static int damon_sysfs_probe_add_dirs(struct damon_sysfs_probe *probe)
{
+ struct damon_sysfs_preps *preps;
struct damon_sysfs_filters *filters;
int err;

- filters = damon_sysfs_filters_alloc();
- if (!filters)
+ preps = damon_sysfs_preps_alloc();
+ if (!preps)
return -ENOMEM;
+ probe->preps = preps;
+
+ err = kobject_init_and_add(&preps->kobj, &damon_sysfs_preps_ktype,
+ &probe->kobj, "preps");
+ if (err)
+ goto put_preps_out;
+
+ filters = damon_sysfs_filters_alloc();
+ if (!filters) {
+ err = -ENOMEM;
+ goto del_preps_out;
+ }
probe->filters = filters;

err = kobject_init_and_add(&filters->kobj, &damon_sysfs_filters_ktype,
&probe->kobj, "filters");
- if (err) {
- kobject_put(&filters->kobj);
- probe->filters = NULL;
- }
+ if (err)
+ goto put_filters_out;
+ return err;
+
+put_filters_out:
+ kobject_put(&filters->kobj);
+ probe->filters = NULL;
+del_preps_out:
+ kobject_del(&preps->kobj);
+put_preps_out:
+ kobject_put(&preps->kobj);
+ probe->preps = NULL;
return err;
}

static void damon_sysfs_probe_rm_dirs(struct damon_sysfs_probe *probe)
{
+ if (probe->preps) {
+ damon_sysfs_preps_rm_dirs(probe->preps);
+ kobject_put(&probe->preps->kobj);
+ }
if (probe->filters) {
damon_sysfs_filters_rm_dirs(probe->filters);
kobject_put(&probe->filters->kobj);
--
2.47.3