memcg: fix lru rotation in isolate_pages

Try to fix memcg's lru rotation sanity: make memcg use the same logic as
the global LRU does.

Now, at __isolate_lru_page() retruns -EBUSY, the page is rotated to the
tail of LRU in global LRU's isolate LRU pages.  But in memcg, it's not
handled.  This makes memcg do the same behavior as global LRU and rotate
LRU in the page is busy.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Minchan Kim <minchan.kim@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 6ceb6f2dbac2ba00366fa9f0184186708a71d1d4..e2fa20dadf408e2d38e6b5a4a61ed4fb9febd3a1 100644 (file)
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -649,6 +649,7 @@ unsigned long mem_cgroup_isolate_pages(unsigned long nr_to_scan,
        int zid = zone_idx(z);
        struct mem_cgroup_per_zone *mz;
        int lru = LRU_FILE * !!file + !!active;
+       int ret;
 
        BUG_ON(!mem_cont);
        mz = mem_cgroup_zoneinfo(mem_cont, nid, zid);
@@ -666,9 +667,19 @@ unsigned long mem_cgroup_isolate_pages(unsigned long nr_to_scan,
                        continue;
 
                scan++;
-               if (__isolate_lru_page(page, mode, file) == 0) {
+               ret = __isolate_lru_page(page, mode, file);
+               switch (ret) {
+               case 0:
                        list_move(&page->lru, dst);
+                       mem_cgroup_del_lru(page);
                        nr_taken++;
+                       break;
+               case -EBUSY:
+                       /* we don't affect global LRU but rotate in our LRU */
+                       mem_cgroup_rotate_lru_list(page, page_lru(page));
+                       break;
+               default:
+                       break;
                }
        }
 

diff --git a/mm/vmscan.c b/mm/vmscan.c
index 4139aa52b941e16d95b20ae481a0775b02158518..e8fa2d9eb212d7cfb739f02305a340fbf023565d 100644 (file)
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -837,7 +837,6 @@ int __isolate_lru_page(struct page *page, int mode, int file)
                 */
                ClearPageLRU(page);
                ret = 0;
-               mem_cgroup_del_lru(page);
        }
 
        return ret;
@@ -885,12 +884,14 @@ static unsigned long isolate_lru_pages(unsigned long nr_to_scan,
                switch (__isolate_lru_page(page, mode, file)) {
                case 0:
                        list_move(&page->lru, dst);
+                       mem_cgroup_del_lru(page);
                        nr_taken++;
                        break;
 
                case -EBUSY:
                        /* else it is being freed elsewhere */
                        list_move(&page->lru, src);
+                       mem_cgroup_rotate_lru_list(page, page_lru(page));
                        continue;
 
                default:
@@ -931,6 +932,7 @@ static unsigned long isolate_lru_pages(unsigned long nr_to_scan,
                                continue;
                        if (__isolate_lru_page(cursor_page, mode, file) == 0) {
                                list_move(&cursor_page->lru, dst);
+                               mem_cgroup_del_lru(page);
                                nr_taken++;
                                scan++;
                        }