nvme-loop: quiesce/unquiesce admin_q instead of start/stop its hw queues

unlike blk_mq_stop_hw_queues and blk_mq_start_stopped_hw_queues
quiescing/unquiescing respects the submission path rcu grace.

Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>

diff --git a/drivers/nvme/target/loop.c b/drivers/nvme/target/loop.c
index 3d51341..6a0b706 100644 (file)
--- a/drivers/nvme/target/loop.c
+++ b/drivers/nvme/target/loop.c
@@ -434,9 +434,10 @@ static void nvme_loop_shutdown_ctrl(struct nvme_loop_ctrl *ctrl)
        if (ctrl->ctrl.state == NVME_CTRL_LIVE)
                nvme_shutdown_ctrl(&ctrl->ctrl);
 
-       blk_mq_stop_hw_queues(ctrl->ctrl.admin_q);
+       blk_mq_quiesce_queue(ctrl->ctrl.admin_q);
        blk_mq_tagset_busy_iter(&ctrl->admin_tag_set,
                                nvme_cancel_request, &ctrl->ctrl);
+       blk_mq_unquiesce_queue(ctrl->ctrl.admin_q);
        nvme_loop_destroy_admin_queue(ctrl);
 }