From: SeongJae Park <sj@xxxxxxxxxx>
DAMON programming interface users can know if specific monitoring ops
set is registered or not using 'damon_is_registered_ops()', but there is
no such method for the user space. To help the case, this commit adds a
new DAMON sysfs file called 'avail_operations' under each context
directory for listing available monitoring ops. Reading the file will
list each registered monitoring ops on each line.
Signed-off-by: SeongJae Park <sj@xxxxxxxxxx>
---
mm/damon/sysfs.c | 19 +++++++++++++++++++
1 file changed, 19 insertions(+)
diff --git a/mm/damon/sysfs.c b/mm/damon/sysfs.c
index 48e434cd43d8..6ad6364780b8 100644
--- a/mm/damon/sysfs.c
+++ b/mm/damon/sysfs.c
@@ -1810,6 +1810,21 @@ static void damon_sysfs_context_rm_dirs(struct damon_sysfs_context *context)
kobject_put(&context->schemes->kobj);
}
+static ssize_t avail_operations_show(struct kobject *kobj,
+ struct kobj_attribute *attr, char *buf)
+{
+ enum damon_ops_id id;
+ int len = 0;
+
+ for (id = 0; id < NR_DAMON_OPS; id++) {
+ if (!damon_is_registered_ops(id))
+ continue;
+ len += sysfs_emit_at(buf, len, "%s\n",
+ damon_sysfs_ops_strs[id]);
+ }
+ return len;
+}
+
static ssize_t operations_show(struct kobject *kobj,
struct kobj_attribute *attr, char *buf)
{
@@ -1840,10 +1855,14 @@ static void damon_sysfs_context_release(struct kobject *kobj)
kfree(container_of(kobj, struct damon_sysfs_context, kobj));
}
+static struct kobj_attribute damon_sysfs_context_avail_operations_attr =
+ __ATTR_RO_MODE(avail_operations, 0400);
+
static struct kobj_attribute damon_sysfs_context_operations_attr =
__ATTR_RW_MODE(operations, 0600);
static struct attribute *damon_sysfs_context_attrs[] = {
+ &damon_sysfs_context_avail_operations_attr.attr,
&damon_sysfs_context_operations_attr.attr,
NULL,
};
--
2.25.1
