mm: remove return value of putback_lru_pages()

putback_lru_page() never can fail.  So it doesn't matter count of "the
number of pages put back".

In addition, users of this functions don't use return value.

Let's remove unnecessary code.

Signed-off-by: Minchan Kim <minchan.kim@gmail.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 2 insertions, 2 deletions

diff --git a/include/linux/migrate.h b/include/linux/migrate.h
index 7f085c97c799..7a07b17d27c5 100644
--- a/include/linux/migrate.h
+++ b/include/linux/migrate.h
@@ -9,7 +9,7 @@ typedef struct page *new_page_t(struct page *, unsigned long private, int **);
 #ifdef CONFIG_MIGRATION
 #define PAGE_MIGRATION 1
 
-extern int putback_lru_pages(struct list_head *l);
+extern void putback_lru_pages(struct list_head *l);
 extern int migrate_page(struct address_space *,
                         struct page *, struct page *);
 extern int migrate_pages(struct list_head *l, new_page_t x,
@@ -25,7 +25,7 @@ extern int migrate_vmas(struct mm_struct *mm,
 #else
 #define PAGE_MIGRATION 0
 
-static inline int putback_lru_pages(struct list_head *l) { return 0; }
+static inline void putback_lru_pages(struct list_head *l) {}
 static inline int migrate_pages(struct list_head *l, new_page_t x,
                 unsigned long private, int offlining) { return -ENOSYS; }