+ mm-damon-return-void-from-damon_set_schemes.patch added to mm-unstable branch

+ mm-damon-return-void-from-damon_set_schemes.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: mm/damon: return void from damon_set_schemes()
has been added to the -mm mm-unstable branch.  Its filename is
     mm-damon-return-void-from-damon_set_schemes.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-damon-return-void-from-damon_set_schemes.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Kaixu Xia <kaixuxia@tencent.com>
Subject: mm/damon: return void from damon_set_schemes()
Date: Fri, 16 Sep 2022 23:20:35 +0800

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.com
Signed-off-by: Kaixu Xia <kaixuxia@tencent.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 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(-)

--- a/include/linux/damon.h~mm-damon-return-void-from-damon_set_schemes
+++ a/include/linux/damon.h
@@ -541,7 +541,7 @@ unsigned int damon_nr_regions(struct dam
 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);
--- a/mm/damon/core.c~mm-damon-return-void-from-damon_set_schemes
+++ a/mm/damon/core.c
@@ -454,10 +454,8 @@ int damon_set_attrs(struct damon_ctx *ct
  *
  * 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 *
 		damon_destroy_scheme(s);
 	for (i = 0; i < nr_schemes; i++)
 		damon_add_scheme(ctx, schemes[i]);
-	return 0;
 }
 
 /**
--- a/mm/damon/dbgfs.c~mm-damon-return-void-from-damon_set_schemes
+++ a/mm/damon/dbgfs.c
@@ -307,11 +307,9 @@ static ssize_t dbgfs_schemes_write(struc
 		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);
--- a/mm/damon/lru_sort.c~mm-damon-return-void-from-damon_set_schemes
+++ a/mm/damon/lru_sort.c
@@ -203,9 +203,7 @@ static int damon_lru_sort_apply_paramete
 	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);
--- a/mm/damon/reclaim.c~mm-damon-return-void-from-damon_set_schemes
+++ a/mm/damon/reclaim.c
@@ -155,9 +155,7 @@ static int damon_reclaim_apply_parameter
 	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;
_

Patches currently in -mm which might be from kaixuxia@tencent.com are

mm-damon-sysfs-simplify-the-judgement-whether-kdamonds-are-busy.patch
mm-damon-core-iterate-the-regions-list-from-current-point-in-damon_set_regions.patch
mm-damon-vaddr-add-a-comment-for-default-case-in-damon_va_apply_scheme.patch
mm-damon-sysfs-use-the-wrapper-directly-to-check-if-the-kdamond-is-running.patch
mm-damon-simplify-the-parameter-passing-for-prepare_access_checks.patch
mm-damon-sysfs-simplify-the-variable-pid-assignment-operation.patch
mm-damon-core-simplify-the-kdamond-stop-mechanism-by-removing-done.patch
mm-damon-use-struct-damon_target-instead-of-void-in-target_valid.patch
mm-damon-return-void-from-damon_set_schemes.patch