mm/damon: return void from damon_set_schemes()

There is no point in returning an int from damon_set_schemes().  It always
returns 0 which is meaningless for the caller, so change it to return void
directly.

Link: https://lkml.kernel.org/r/1663341635-12675-1-git-send-email-kaixuxia@tencent.comSigned-off-by: Kaixu Xia <kaixuxia@tencent.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

include/linux/damon.h

@@ -541,7 +541,7 @@ unsigned int damon_nr_regions(struct damon_target *t);
 struct damon_ctx *damon_new_ctx(void);
 void damon_destroy_ctx(struct damon_ctx *ctx);
 int damon_set_attrs(struct damon_ctx *ctx, struct damon_attrs *attrs);
-int damon_set_schemes(struct damon_ctx *ctx,
+void damon_set_schemes(struct damon_ctx *ctx,
 			struct damos **schemes, ssize_t nr_schemes);
 int damon_nr_running_ctxs(void);
 bool damon_is_registered_ops(enum damon_ops_id id);

mm/damon/core.c

@@ -454,10 +454,8 @@ int damon_set_attrs(struct damon_ctx *ctx, struct damon_attrs *attrs)
  *
  * This function should not be called while the kdamond of the context is
  * running.
- *
- * Return: 0 if success, or negative error code otherwise.
  */
-int damon_set_schemes(struct damon_ctx *ctx, struct damos **schemes,
+void damon_set_schemes(struct damon_ctx *ctx, struct damos **schemes,
 			ssize_t nr_schemes)
 {
 	struct damos *s, *next;
@@ -467,7 +465,6 @@ int damon_set_schemes(struct damon_ctx *ctx, struct damos **schemes,
 		damon_destroy_scheme(s);
 	for (i = 0; i < nr_schemes; i++)
 		damon_add_scheme(ctx, schemes[i]);
-	return 0;
 }
 
 /**

mm/damon/dbgfs.c

@@ -307,11 +307,9 @@ static ssize_t dbgfs_schemes_write(struct file *file, const char __user *buf,
 		goto unlock_out;
 	}
 
-	ret = damon_set_schemes(ctx, schemes, nr_schemes);
-	if (!ret) {
+	damon_set_schemes(ctx, schemes, nr_schemes);
 	ret = count;
 	nr_schemes = 0;
-	}
 
 unlock_out:
 	mutex_unlock(&ctx->kdamond_lock);

mm/damon/lru_sort.c

@@ -203,9 +203,7 @@ static int damon_lru_sort_apply_parameters(void)
 	scheme = damon_lru_sort_new_hot_scheme(hot_thres);
 	if (!scheme)
 		return -ENOMEM;
-	err = damon_set_schemes(ctx, &scheme, 1);
-	if (err)
-		return err;
+	damon_set_schemes(ctx, &scheme, 1);
 
 	cold_thres = cold_min_age / damon_lru_sort_mon_attrs.aggr_interval;
 	scheme = damon_lru_sort_new_cold_scheme(cold_thres);

mm/damon/reclaim.c

@@ -155,9 +155,7 @@ static int damon_reclaim_apply_parameters(void)
 	scheme = damon_reclaim_new_scheme();
 	if (!scheme)
 		return -ENOMEM;
-	err = damon_set_schemes(ctx, &scheme, 1);
-	if (err)
-		return err;
+	damon_set_schemes(ctx, &scheme, 1);
 
 	if (monitor_region_start > monitor_region_end)
 		return -EINVAL;