memcg: remove mem_cgroup_uncharge_list()

All users have been converted to mem_cgroup_uncharge_folios() so we can
remove this API.

Link: https://lkml.kernel.org/r/20240227174254.710559-14-willy@infradead.orgSigned-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Ryan Roberts <ryan.roberts@arm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

include/linux/memcontrol.h

@@ -713,14 +713,6 @@ static inline void mem_cgroup_uncharge(struct folio *folio)
 	__mem_cgroup_uncharge(folio);
 }
 
-void __mem_cgroup_uncharge_list(struct list_head *page_list);
-static inline void mem_cgroup_uncharge_list(struct list_head *page_list)
-{
-	if (mem_cgroup_disabled())
-		return;
-	__mem_cgroup_uncharge_list(page_list);
-}
-
 void __mem_cgroup_uncharge_folios(struct folio_batch *folios);
 static inline void mem_cgroup_uncharge_folios(struct folio_batch *folios)
 {
@@ -1301,10 +1293,6 @@ static inline void mem_cgroup_uncharge(struct folio *folio)
 {
 }
 
-static inline void mem_cgroup_uncharge_list(struct list_head *page_list)
-{
-}
-
 static inline void mem_cgroup_uncharge_folios(struct folio_batch *folios)
 {
 }

mm/memcontrol.c

@@ -7513,25 +7513,6 @@ void __mem_cgroup_uncharge(struct folio *folio)
 	uncharge_batch(&ug);
 }
 
-/**
- * __mem_cgroup_uncharge_list - uncharge a list of page
- * @page_list: list of pages to uncharge
- *
- * Uncharge a list of pages previously charged with
- * __mem_cgroup_charge().
- */
-void __mem_cgroup_uncharge_list(struct list_head *page_list)
-{
-	struct uncharge_gather ug;
-	struct folio *folio;
-
-	uncharge_gather_clear(&ug);
-	list_for_each_entry(folio, page_list, lru)
-		uncharge_folio(folio, &ug);
-	if (ug.memcg)
-		uncharge_batch(&ug);
-}
-
 void __mem_cgroup_uncharge_folios(struct folio_batch *folios)
 {
 	struct uncharge_gather ug;