mm: free swap cache aggressively if memcg swap is full
Swap cache pages are freed aggressively if swap is nearly full (>50%
currently), because otherwise we are likely to stop scanning anonymous
when we near the swap limit even if there is plenty of freeable swap cache
pages. We should follow the same trend in case of memory cgroup, which
has its own swap limit.
Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/swapfile.c b/mm/swapfile.c
index 22a7a1f..c43f654 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -1006,7 +1006,7 @@
* Also recheck PageSwapCache now page is locked (above).
*/
if (PageSwapCache(page) && !PageWriteback(page) &&
- (!page_mapped(page) || vm_swap_full())) {
+ (!page_mapped(page) || mem_cgroup_swap_full(page))) {
delete_from_swap_cache(page);
SetPageDirty(page);
}