3 files changed, 10 insertions, 1 deletions

diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c
index dfb8cb0af13a..5ba1e0d841b4 100644
--- a/block/bfq-iosched.c
+++ b/block/bfq-iosched.c
@@ -5396,7 +5396,7 @@ static unsigned int bfq_update_depths(struct bfq_data *bfqd,
         return min_shallow;
 }
 
-static int bfq_init_hctx(struct blk_mq_hw_ctx *hctx, unsigned int index)
+static void bfq_depth_updated(struct blk_mq_hw_ctx *hctx)
 {
         struct bfq_data *bfqd = hctx->queue->elevator->elevator_data;
         struct blk_mq_tags *tags = hctx->sched_tags;
@@ -5404,6 +5404,11 @@ static int bfq_init_hctx(struct blk_mq_hw_ctx *hctx, unsigned int index)
 
         min_shallow = bfq_update_depths(bfqd, &tags->bitmap_tags);
         sbitmap_queue_min_shallow_depth(&tags->bitmap_tags, min_shallow);
+}
+
+static int bfq_init_hctx(struct blk_mq_hw_ctx *hctx, unsigned int index)
+{
+        bfq_depth_updated(hctx);
         return 0;
 }
 
@@ -5826,6 +5831,7 @@ static struct elevator_type iosched_bfq_mq = {
                 .requests_merged        = bfq_requests_merged,
                 .request_merged         = bfq_request_merged,
                 .has_work               = bfq_has_work,
+                .depth_updated          = bfq_depth_updated,
                 .init_hctx              = bfq_init_hctx,
                 .init_sched             = bfq_init_queue,
                 .exit_sched             = bfq_exit_queue,
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 9516304a38ee..fc60ed7e940e 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -3135,6 +3135,8 @@ int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr)
                 }
                 if (ret)
                         break;
+                if (q->elevator && q->elevator->type->ops.depth_updated)
+                        q->elevator->type->ops.depth_updated(hctx);
         }
 
         if (!ret)
diff --git a/include/linux/elevator.h b/include/linux/elevator.h
index 2e9e2763bf47..6e8bc53740f0 100644
--- a/include/linux/elevator.h
+++ b/include/linux/elevator.h
@@ -31,6 +31,7 @@ struct elevator_mq_ops {
         void (*exit_sched)(struct elevator_queue *);
         int (*init_hctx)(struct blk_mq_hw_ctx *, unsigned int);
         void (*exit_hctx)(struct blk_mq_hw_ctx *, unsigned int);
+        void (*depth_updated)(struct blk_mq_hw_ctx *);
 
         bool (*allow_merge)(struct request_queue *, struct request *, struct bio *);
         bool (*bio_merge)(struct blk_mq_hw_ctx *, struct bio *);