From: Chen Ridong <chenridong@huawei.com>

Currently, mem_cgroup_usage is only used for v1, just move it to
memcontrol-v1.c

Signed-off-by: Chen Ridong <chenridong@huawei.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
---
 mm/memcontrol-v1.c | 22 ++++++++++++++++++++++
 mm/memcontrol-v1.h |  2 --
 mm/memcontrol.c    | 22 ----------------------
 3 files changed, 22 insertions(+), 24 deletions(-)

diff --git a/mm/memcontrol-v1.c b/mm/memcontrol-v1.c
index 6eed14bff742..0b50cb122ff3 100644
--- a/mm/memcontrol-v1.c
+++ b/mm/memcontrol-v1.c
@@ -427,6 +427,28 @@ static int mem_cgroup_move_charge_write(struct cgroup_subsys_state *css,
 }
 #endif
 
+static unsigned long mem_cgroup_usage(struct mem_cgroup *memcg, bool swap)
+{
+	unsigned long val;
+
+	if (mem_cgroup_is_root(memcg)) {
+		/*
+		 * Approximate root's usage from global state. This isn't
+		 * perfect, but the root usage was always an approximation.
+		 */
+		val = global_node_page_state(NR_FILE_PAGES) +
+			global_node_page_state(NR_ANON_MAPPED);
+		if (swap)
+			val += total_swap_pages - get_nr_swap_pages();
+	} else {
+		if (!swap)
+			val = page_counter_read(&memcg->memory);
+		else
+			val = page_counter_read(&memcg->memsw);
+	}
+	return val;
+}
+
 static void __mem_cgroup_threshold(struct mem_cgroup *memcg, bool swap)
 {
 	struct mem_cgroup_threshold_ary *t;
diff --git a/mm/memcontrol-v1.h b/mm/memcontrol-v1.h
index 6358464bb416..e92b21af92b1 100644
--- a/mm/memcontrol-v1.h
+++ b/mm/memcontrol-v1.h
@@ -22,8 +22,6 @@
 	     iter != NULL;				\
 	     iter = mem_cgroup_iter(NULL, iter, NULL))
 
-unsigned long mem_cgroup_usage(struct mem_cgroup *memcg, bool swap);
-
 void drain_all_stock(struct mem_cgroup *root_memcg);
 
 unsigned long memcg_events(struct mem_cgroup *memcg, int event);
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index e2e49f4ec9e0..dbe7d8f93072 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -3272,28 +3272,6 @@ void folio_split_memcg_refs(struct folio *folio, unsigned old_order,
 	css_get_many(&__folio_memcg(folio)->css, new_refs);
 }
 
-unsigned long mem_cgroup_usage(struct mem_cgroup *memcg, bool swap)
-{
-	unsigned long val;
-
-	if (mem_cgroup_is_root(memcg)) {
-		/*
-		 * Approximate root's usage from global state. This isn't
-		 * perfect, but the root usage was always an approximation.
-		 */
-		val = global_node_page_state(NR_FILE_PAGES) +
-			global_node_page_state(NR_ANON_MAPPED);
-		if (swap)
-			val += total_swap_pages - get_nr_swap_pages();
-	} else {
-		if (!swap)
-			val = page_counter_read(&memcg->memory);
-		else
-			val = page_counter_read(&memcg->memsw);
-	}
-	return val;
-}
-
 static int memcg_online_kmem(struct mem_cgroup *memcg)
 {
 	struct obj_cgroup *objcg;
-- 
2.34.1

On Thu, Dec 11, 2025 at 01:30:18AM +0000, Chen Ridong wrote:
> From: Chen Ridong <chenridong@huawei.com>
> 
> Currently, mem_cgroup_usage is only used for v1, just move it to
> memcontrol-v1.c
> 
> Signed-off-by: Chen Ridong <chenridong@huawei.com>
> Acked-by: Michal Hocko <mhocko@suse.com>
> Acked-by: Johannes Weiner <hannes@cmpxchg.org>

Acked-by: Shakeel Butt <shakeel.butt@linux.dev>