Re: [PATCH 3/8] nvme-loop: quiesce admin_q instead of stopping hw queues
From: Sagi Grimberg <sagi@grimberg.me>
Date: 2017-07-04 09:24:20
Also in:
linux-nvme
From: Sagi Grimberg <sagi@grimberg.me>
Date: 2017-07-04 09:24:20
Also in:
linux-nvme
quoted
diff --git a/drivers/nvme/target/loop.c b/drivers/nvme/target/loop.c index 3d51341e62ee..891002ee005f 100644 --- a/drivers/nvme/target/loop.c +++ b/drivers/nvme/target/loop.c@@ -434,7 +434,7 @@ 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); nvme_loop_destroy_admin_queue(ctrl);Is the queue killed before calling nvme_loop_destroy_admin_queue()?
No, its not.
If not, simply quiescing and not unquiescing will hang in blk_cleanup_queue().
Why should it? blk_cleanup_queue does not hang, even under IO load...
So I suggest to put blk_mq_unquiesce_queue() after blk_mq_tagset_busy_iter().
I can do that, but I don't understand why...