mm/damon/core: commit damos->migrate_dests

When committing new scheme parameters from the sysfs, copy the
migrate_dests struct of the source schemes into the destination schemes.

Link: https://lkml.kernel.org/r/20250709005952.17776-8-bijan311@gmail.com
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/core.c b/mm/damon/core.c
index 6c8170d4f695adf3c221cba3adba3442751beae6..2714a7a023db38900a2ff87c73babcb7b36a2752 100644 (file)
--- a/mm/damon/core.c
+++ b/mm/damon/core.c
@@ -943,6 +943,41 @@ static void damos_set_filters_default_reject(struct damos *s)
                damos_filters_default_reject(&s->ops_filters);
 }
 
+static int damos_commit_dests(struct damos *dst, struct damos *src)
+{
+       struct damos_migrate_dests *dst_dests, *src_dests;
+
+       dst_dests = &dst->migrate_dests;
+       src_dests = &src->migrate_dests;
+
+       if (dst_dests->nr_dests != src_dests->nr_dests) {
+               kfree(dst_dests->node_id_arr);
+               kfree(dst_dests->weight_arr);
+
+               dst_dests->node_id_arr = kmalloc_array(src_dests->nr_dests,
+                       sizeof(*dst_dests->node_id_arr), GFP_KERNEL);
+               if (!dst_dests->node_id_arr) {
+                       dst_dests->weight_arr = NULL;
+                       return -ENOMEM;
+               }
+
+               dst_dests->weight_arr = kmalloc_array(src_dests->nr_dests,
+                       sizeof(*dst_dests->weight_arr), GFP_KERNEL);
+               if (!dst_dests->weight_arr) {
+                       /* ->node_id_arr will be freed by scheme destruction */
+                       return -ENOMEM;
+               }
+       }
+
+       dst_dests->nr_dests = src_dests->nr_dests;
+       for (int i = 0; i < src_dests->nr_dests; i++) {
+               dst_dests->node_id_arr[i] = src_dests->node_id_arr[i];
+               dst_dests->weight_arr[i] = src_dests->weight_arr[i];
+       }
+
+       return 0;
+}
+
 static int damos_commit_filters(struct damos *dst, struct damos *src)
 {
        int err;
@@ -984,6 +1019,10 @@ static int damos_commit(struct damos *dst, struct damos *src)
        dst->wmarks = src->wmarks;
        dst->target_nid = src->target_nid;
 
+       err = damos_commit_dests(dst, src);
+       if (err)
+               return err;
+
        err = damos_commit_filters(dst, src);
        return err;
 }