Merge tag 'for-linus-20181012' of git://git.kernel.dk/linux-block

Jens writes:
  "block fix for 4.19-rc

   Just a single fix that should go in, fixing a regression introduced
   in the blk-wbt code."

* tag 'for-linus-20181012' of git://git.kernel.dk/linux-block:
  blk-wbt: wake up all when we scale up, not down

block/blk-wbt.c

@@ -310,6 +310,7 @@ static void scale_up(struct rq_wb *rwb)
 	rq_depth_scale_up(&rwb->rq_depth);
 	calc_wb_limits(rwb);
 	rwb->unknown_cnt = 0;
+	rwb_wake_all(rwb);
 	rwb_trace_step(rwb, "scale up");
 }
 
@@ -318,7 +319,6 @@ static void scale_down(struct rq_wb *rwb, bool hard_throttle)
 	rq_depth_scale_down(&rwb->rq_depth, hard_throttle);
 	calc_wb_limits(rwb);
 	rwb->unknown_cnt = 0;
-	rwb_wake_all(rwb);
 	rwb_trace_step(rwb, "scale down");
 }