+	struct bfq_queue *bfqq = rq ? RQ_BFQQ(rq) : NULL;
 
-#if defined(CONFIG_BFQ_GROUP_IOSCHED) && defined(CONFIG_DEBUG_BLK_CGROUP)
-	bfqq = rq ? RQ_BFQQ(rq) : NULL;
 	if (!idle_timer_disabled && !bfqq)
-		return rq;
+		return;
 
 	/*
 	 * rq and bfqq are guaranteed to exist until this function

@@ -3732,7 +3713,7 @@ static struct request *bfq_dispatch_request(struct blk_mq_hw_ctx *hctx)
 	 * In addition, the following queue lock guarantees that
 	 * bfqq_group(bfqq) exists as well.
 	 */
-	spin_lock_irq(hctx->queue->queue_lock);
+	spin_lock_irq(queue_lock);
 	if (idle_timer_disabled)
 		/*
 		 * Since the idle timer has been disabled,

@@ -3751,9 +3732,37 @@ static struct request *bfq_dispatch_request(struct blk_mq_hw_ctx *hctx)
 		bfqg_stats_set_start_empty_time(bfqg);
 		bfqg_stats_update_io_remove(bfqg, rq->cmd_flags);
 	}
-	spin_unlock_irq(hctx->queue->queue_lock);
+	spin_unlock_irq(queue_lock);
+}
+#else
+static inline void bfq_update_dispatch_stats(struct request *rq,
+					     spinlock_t *queue_lock,
+					     struct bfq_queue *in_serv_queue,
+					     bool idle_timer_disabled) {}
 #endif
 
+static struct request *bfq_dispatch_request(struct blk_mq_hw_ctx *hctx)
+{
+	struct bfq_data *bfqd = hctx->queue->elevator->elevator_data;
+	struct request *rq;
+	struct bfq_queue *in_serv_queue;
+	bool waiting_rq, idle_timer_disabled;
+
+	spin_lock_irq(&bfqd->lock);
+
+	in_serv_queue = bfqd->in_service_queue;
+	waiting_rq = in_serv_queue && bfq_bfqq_wait_request(in_serv_queue);
+
+	rq = __bfq_dispatch_request(hctx);
+
+	idle_timer_disabled =
+		waiting_rq && !bfq_bfqq_wait_request(in_serv_queue);
+
+	spin_unlock_irq(&bfqd->lock);
+
+	bfq_update_dispatch_stats(rq, hctx->queue->queue_lock, in_serv_queue,
+				  idle_timer_disabled);
+
 	return rq;
 }
 

@@ -4276,16 +4285,46 @@ static bool __bfq_insert_request(struct bfq_data *bfqd, struct request *rq)
 	return idle_timer_disabled;
 }
 
+#if defined(CONFIG_BFQ_GROUP_IOSCHED) && defined(CONFIG_DEBUG_BLK_CGROUP)
+static inline void bfq_update_insert_stats(struct bfq_queue *bfqq,
+					   spinlock_t *queue_lock,
+					   bool idle_timer_disabled,
+					   unsigned int cmd_flags)
+{
+	if (!bfqq)
+		return;
+
+	/*
+	 * bfqq still exists, because it can disappear only after
+	 * either it is merged with another queue, or the process it
+	 * is associated with exits. But both actions must be taken by
+	 * the same process currently executing this flow of
+	 * instructions.
+	 *
+	 * In addition, the following queue lock guarantees that
+	 * bfqq_group(bfqq) exists as well.
+	 */
+	spin_lock_irq(queue_lock);
+	bfqg_stats_update_io_add(bfqq_group(bfqq), bfqq, cmd_flags);
+	if (idle_timer_disabled)
+		bfqg_stats_update_idle_time(bfqq_group(bfqq));
+	spin_unlock_irq(queue_lock);
+}
+#else
+static inline void bfq_update_insert_stats(struct bfq_queue *bfqq,
+					   spinlock_t *queue_lock,
+					   bool idle_timer_disabled,
+					   unsigned int cmd_flags) {}
+#endif