mm: introduce page_lru_base_type()

Instead of abusing page_is_file_cache() for LRU list index arithmetic, add
another helper with a more appropriate name and convert the non-boolean
users of page_is_file_cache() accordingly.

This new helper gives the LRU base type a page is supposed to live on,
inactive anon or inactive file.

[hugh.dickins@tiscali.co.uk: convert del_page_from_lru() also]
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@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/mm/swap.c b/mm/swap.c
index cb29ae5..168d53e 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -118,7 +118,7 @@ static void pagevec_move_tail(struct pagevec *pvec)
 			spin_lock(&zone->lru_lock);
 		}
 		if (PageLRU(page) && !PageActive(page) && !PageUnevictable(page)) {
-			int lru = page_is_file_cache(page);
+			int lru = page_lru_base_type(page);
 			list_move_tail(&page->lru, &zone->lru[lru].list);
 			pgmoved++;
 		}
@@ -181,7 +181,7 @@ void activate_page(struct page *page)
 	spin_lock_irq(&zone->lru_lock);
 	if (PageLRU(page) && !PageActive(page) && !PageUnevictable(page)) {
 		int file = page_is_file_cache(page);
-		int lru = LRU_BASE + file;
+		int lru = page_lru_base_type(page);
 		del_page_from_lru_list(zone, page, lru);
 
 		SetPageActive(page);