mm/damon/sysfs-schemes: support DAMOS_QUOTA_NODE_MEMCG_USED_BP

Add support of DAMOS_QUOTA_NODE_MEMCG_USED_BP.  For this, extend quota
goal metric inputs for the new metric, and update DAMOS core layer request
construction logic to set the target cgroup, which is specified by the
user, via the 'path' file.

Link: https://lkml.kernel.org/r/20251017212706.183502-6-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/damon/sysfs-schemes.c b/mm/damon/sysfs-schemes.c
index 2c440a2b80e62881096fd42810bf66782d10742f..c679e62fd4b93925347847d7078a8de389b7fd52 100644 (file)
--- a/mm/damon/sysfs-schemes.c
+++ b/mm/damon/sysfs-schemes.c
@@ -1030,6 +1030,10 @@ struct damos_sysfs_qgoal_metric_name damos_sysfs_qgoal_metric_names[] = {
                .metric = DAMOS_QUOTA_NODE_MEM_FREE_BP,
                .name = "node_mem_free_bp",
        },
+       {
+               .metric = DAMOS_QUOTA_NODE_MEMCG_USED_BP,
+               .name = "node_memcg_used_bp",
+       },
 };
 
 static ssize_t target_metric_show(struct kobject *kobj,
@@ -2526,7 +2530,7 @@ static int damos_sysfs_add_quota_score(
                struct damos_quota *quota)
 {
        struct damos_quota_goal *goal;
-       int i;
+       int i, err;
 
        for (i = 0; i < sysfs_goals->nr; i++) {
                struct damos_sysfs_quota_goal *sysfs_goal =
@@ -2547,6 +2551,15 @@ static int damos_sysfs_add_quota_score(
                case DAMOS_QUOTA_NODE_MEM_FREE_BP:
                        goal->nid = sysfs_goal->nid;
                        break;
+               case DAMOS_QUOTA_NODE_MEMCG_USED_BP:
+                       err = damon_sysfs_memcg_path_to_id(
+                                       sysfs_goal->path, &goal->memcg_id);
+                       if (err) {
+                               damos_destroy_quota_goal(goal);
+                               return err;
+                       }
+                       goal->nid = sysfs_goal->nid;
+                       break;
                default:
                        break;
                }