mm: return boolean from page_is_file_cache()

page_is_file_cache() has been used for both boolean checks and LRU
arithmetic, which was always a bit weird.

Now that page_lru_base_type() exists for LRU arithmetic, make
page_is_file_cache() a real predicate function and adjust the
boolean-using callsites to drop those pesky double negations.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
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, 1 insertions, 1 deletions

diff --git a/mm/vmscan.c b/mm/vmscan.c
index 30e56ee833f8..172119caebcc 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -821,7 +821,7 @@ int __isolate_lru_page(struct page *page, int mode, int file)
         if (mode != ISOLATE_BOTH && (!PageActive(page) != !mode))
                 return ret;
 
-        if (mode != ISOLATE_BOTH && (!page_is_file_cache(page) != !file))
+        if (mode != ISOLATE_BOTH && page_is_file_cache(page) != file)
                 return ret;
 
         /*