1 files changed, 15 insertions, 0 deletions

diff --git a/mm/vmscan.c b/mm/vmscan.c
index 2f7c6ae8fae0..387422470c95 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -277,6 +277,21 @@ unsigned long shrink_slab(struct shrink_control *shrink,
                 }
 
                 /*
+                 * We need to avoid excessive windup on filesystem shrinkers
+                 * due to large numbers of GFP_NOFS allocations causing the
+                 * shrinkers to return -1 all the time. This results in a large
+                 * nr being built up so when a shrink that can do some work
+                 * comes along it empties the entire cache due to nr >>>
+                 * max_pass.  This is bad for sustaining a working set in
+                 * memory.
+                 *
+                 * Hence only allow the shrinker to scan the entire cache when
+                 * a large delta change is calculated directly.
+                 */
+                if (delta < max_pass / 4)
+                        total_scan = min(total_scan, max_pass / 2);
+
+                /*
                  * Avoid risking looping forever due to too large nr value:
                  * never try to free more than twice the estimate number of
                  * freeable entries.