mm/damon/sysfs-schemes: set damos->migrate_dests

Pass user-specified multiple DAMOS action destinations and their weights
to DAMON core API, so that user requests can really work.

Link: https://lkml.kernel.org/r/20250709005952.17776-5-bijan311@gmail.com
Signed-off-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Bijan Tabatabai <bijantabatab@micron.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ravi Shankar Jonnalagadda <ravis.opensrc@micron.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/damon/sysfs-schemes.c b/mm/damon/sysfs-schemes.c
index b9434cdaacdc084fb49efcbd20cbcd0590f1dae4..74056bcd6a2c58a75f8df8f6c4d8baa631c996a9 100644 (file)
--- a/mm/damon/sysfs-schemes.c
+++ b/mm/damon/sysfs-schemes.c
@@ -2576,6 +2576,29 @@ void damos_sysfs_update_effective_quotas(
        }
 }
 
+static int damos_sysfs_add_migrate_dest(struct damos *scheme,
+               struct damos_sysfs_dests *sysfs_dests)
+{
+       struct damos_migrate_dests *dests = &scheme->migrate_dests;
+       int i;
+
+       dests->node_id_arr = kmalloc_array(sysfs_dests->nr,
+                       sizeof(*dests->node_id_arr), GFP_KERNEL);
+       if (!dests->node_id_arr)
+               return -ENOMEM;
+       dests->weight_arr = kmalloc_array(sysfs_dests->nr,
+                       sizeof(*dests->weight_arr), GFP_KERNEL);
+       if (!dests->weight_arr)
+               /* ->node_id_arr will be freed by scheme destruction */
+               return -ENOMEM;
+       for (i = 0; i < sysfs_dests->nr; i++) {
+               dests->node_id_arr[i] = sysfs_dests->dests_arr[i]->id;
+               dests->weight_arr[i] = sysfs_dests->dests_arr[i]->weight;
+       }
+       dests->nr_dests = sysfs_dests->nr;
+       return 0;
+}
+
 static struct damos *damon_sysfs_mk_scheme(
                struct damon_sysfs_scheme *sysfs_scheme)
 {
@@ -2638,6 +2661,11 @@ static struct damos *damon_sysfs_mk_scheme(
                damon_destroy_scheme(scheme);
                return NULL;
        }
+       err = damos_sysfs_add_migrate_dest(scheme, sysfs_scheme->dests);
+       if (err) {
+               damon_destroy_scheme(scheme);
+               return NULL;
+       }
        return scheme;
 }