1 files changed, 16 insertions, 0 deletions

diff --git a/block/blk-throttle.c b/block/blk-throttle.c
index 004be80fd89..2d134b7c40a 100644
--- a/block/blk-throttle.c
+++ b/block/blk-throttle.c
@@ -355,6 +355,12 @@ throtl_start_new_slice(struct throtl_data *td, struct throtl_grp *tg, bool rw)
                         tg->slice_end[rw], jiffies);
 }
 
+static inline void throtl_set_slice_end(struct throtl_data *td,
+                struct throtl_grp *tg, bool rw, unsigned long jiffy_end)
+{
+        tg->slice_end[rw] = roundup(jiffy_end, throtl_slice);
+}
+
 static inline void throtl_extend_slice(struct throtl_data *td,
                 struct throtl_grp *tg, bool rw, unsigned long jiffy_end)
 {
@@ -391,6 +397,16 @@ throtl_trim_slice(struct throtl_data *td, struct throtl_grp *tg, bool rw)
         if (throtl_slice_used(td, tg, rw))
                 return;
 
+        /*
+         * A bio has been dispatched. Also adjust slice_end. It might happen
+         * that initially cgroup limit was very low resulting in high
+         * slice_end, but later limit was bumped up and bio was dispached
+         * sooner, then we need to reduce slice_end. A high bogus slice_end
+         * is bad because it does not allow new slice to start.
+         */
+
+        throtl_set_slice_end(td, tg, rw, jiffies + throtl_slice);
+
         time_elapsed = jiffies - tg->slice_start[rw];
 
         nr_slices = time_elapsed / throtl_slice;