1 files changed, 19 insertions, 1 deletions

diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index cc351e6f9ed..6a8bb693b42 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -1086,6 +1086,10 @@ static void balance_dirty_pages(struct address_space *mapping,
                 task_ratelimit = (u64)dirty_ratelimit *
                                         pos_ratio >> RATELIMIT_CALC_SHIFT;
                 pause = (HZ * pages_dirtied) / (task_ratelimit | 1);
+                if (unlikely(pause <= 0)) {
+                        pause = 1; /* avoid resetting nr_dirtied_pause below */
+                        break;
+                }
                 pause = min(pause, max_pause);
 
 pause:
@@ -1107,7 +1111,21 @@ pause:
                 bdi->dirty_exceeded = 0;
 
         current->nr_dirtied = 0;
-        current->nr_dirtied_pause = dirty_poll_interval(nr_dirty, dirty_thresh);
+        if (pause == 0) { /* in freerun area */
+                current->nr_dirtied_pause =
+                                dirty_poll_interval(nr_dirty, dirty_thresh);
+        } else if (pause <= max_pause / 4 &&
+                   pages_dirtied >= current->nr_dirtied_pause) {
+                current->nr_dirtied_pause = clamp_val(
+                                        dirty_ratelimit * (max_pause / 2) / HZ,
+                                        pages_dirtied + pages_dirtied / 8,
+                                        pages_dirtied * 4);
+        } else if (pause >= max_pause) {
+                current->nr_dirtied_pause = 1 | clamp_val(
+                                        dirty_ratelimit * (max_pause / 2) / HZ,
+                                        pages_dirtied / 4,
+                                        pages_dirtied - pages_dirtied / 8);
+        }
 
         if (writeback_in_progress(bdi))
                 return;