vmscan: get_scan_ratio() cleanup

The get_scan_ratio() should have all scan-ratio related calculations.
Thus, this patch move some calculation into get_scan_ratio.

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

1 files changed, 14 insertions, 9 deletions

diff --git a/mm/vmscan.c b/mm/vmscan.c
index 96ebe6608d5c..62782057fcb9 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1501,6 +1501,13 @@ static void get_scan_ratio(struct zone *zone, struct scan_control *sc,
         unsigned long ap, fp;
         struct zone_reclaim_stat *reclaim_stat = get_reclaim_stat(zone, sc);
 
+        /* If we have no swap space, do not bother scanning anon pages. */
+        if (!sc->may_swap || (nr_swap_pages <= 0)) {
+                percent[0] = 0;
+                percent[1] = 100;
+                return;
+        }
+
         anon  = zone_nr_lru_pages(zone, sc, LRU_ACTIVE_ANON) +
                 zone_nr_lru_pages(zone, sc, LRU_INACTIVE_ANON);
         file  = zone_nr_lru_pages(zone, sc, LRU_ACTIVE_FILE) +
@@ -1598,22 +1605,20 @@ static void shrink_zone(int priority, struct zone *zone,
         unsigned long nr_reclaimed = sc->nr_reclaimed;
         unsigned long nr_to_reclaim = sc->nr_to_reclaim;
         struct zone_reclaim_stat *reclaim_stat = get_reclaim_stat(zone, sc);
-        int noswap = 0;
 
-        /* If we have no swap space, do not bother scanning anon pages. */
-        if (!sc->may_swap || (nr_swap_pages <= 0)) {
-                noswap = 1;
-                percent[0] = 0;
-                percent[1] = 100;
-        } else
-                get_scan_ratio(zone, sc, percent);
+        get_scan_ratio(zone, sc, percent);
 
         for_each_evictable_lru(l) {
                 int file = is_file_lru(l);
                 unsigned long scan;
 
+                if (percent[file] == 0) {
+                        nr[l] = 0;
+                        continue;
+                }
+
                 scan = zone_nr_lru_pages(zone, sc, l);
-                if (priority || noswap) {
+                if (priority) {
                         scan >>= priority;
                         scan = (scan * percent[file]) / 100;
                 }