[PATCH] mm/damon: return void from damon_set_schemes()

[PATCH] mm/damon: return void from damon_set_schemes()

[xiakaixu1987]

From: Kaixu Xia <kaixuxia@tencent.com>

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.

Signed-off-by: Kaixu Xia <kaixuxia@tencent.com>
---
 include/linux/damon.h | 2 +-
 mm/damon/core.c       | 5 +----
 mm/damon/dbgfs.c      | 8 +++-----
 mm/damon/lru_sort.c   | 4 +---
 mm/damon/reclaim.c    | 4 +---
 5 files changed, 7 insertions(+), 16 deletions(-)

diff --git a/include/linux/damon.h b/include/linux/damon.h
index 1dda8d0068e5..e7808a84675f 100644
--- a/include/linux/damon.h
+++ b/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);
diff --git a/mm/damon/core.c b/mm/damon/core.c
index a843673c11cf..9c80c6eb00c2 100644
--- a/mm/damon/core.c
+++ b/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;
 }
 
 /**
diff --git a/mm/damon/dbgfs.c b/mm/damon/dbgfs.c
index c00eba4448d8..6f0ae7d3ae39 100644
--- a/mm/damon/dbgfs.c
+++ b/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) {
-		ret = count;
-		nr_schemes = 0;
-	}
+	damon_set_schemes(ctx, schemes, nr_schemes);
+	ret = count;
+	nr_schemes = 0;
 
 unlock_out:
 	mutex_unlock(&ctx->kdamond_lock);
diff --git a/mm/damon/lru_sort.c b/mm/damon/lru_sort.c
index abfaf471e3e9..0abb9f8aa9af 100644
--- a/mm/damon/lru_sort.c
+++ b/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);
diff --git a/mm/damon/reclaim.c b/mm/damon/reclaim.c
index 039fa55e0ae9..3d59ab11b7b3 100644
--- a/mm/damon/reclaim.c
+++ b/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;
-- 
2.27.0

Re: [PATCH] mm/damon: return void from damon_set_schemes()

[SeongJae Park]

On Fri, 16 Sep 2022 23:20:35 +0800 xiakaixu1987@gmail.com wrote:

> From: Kaixu Xia <kaixuxia@tencent.com>
> 
> 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.
> 
> Signed-off-by: Kaixu Xia <kaixuxia@tencent.com>

Reviewed-by: SeongJae Park <sj@kernel.org>


Thanks,
SJ

[...]

Re: [PATCH] mm/damon: return void from damon_set_schemes()

[Muchun Song]

> On Sep 16, 2022, at 23:20, xiakaixu1987@gmail.com wrote:
> 
> From: Kaixu Xia <kaixuxia@tencent.com>
> 
> 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.
> 
> Signed-off-by: Kaixu Xia <kaixuxia@tencent.com>

Reviewed-by: Muchun Song <songmuchun@bytedance.com>

Thanks.