[PATCH 5/8] nbd: quiesce request queues to make sure no submissions are inflight

[Ming Lei]

On Tue, Jul 04, 2017 at 10:55:09AM +0300, Sagi Grimberg wrote:
> We must make sure that no requests are being queued before we iterate
> over the tags. quiesce/unquiesce the request queue istead of start/stop
> hw queues.
> 
> Cc: Josef Bacik <jbacik at fb.com>
> Signed-off-by: Sagi Grimberg <sagi at grimberg.me>
> ---
>  drivers/block/nbd.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
> index 977ec960dd2f..dea7d85134ee 100644
> --- a/drivers/block/nbd.c
> +++ b/drivers/block/nbd.c
> @@ -661,9 +661,9 @@ static void nbd_clear_req(struct request *req, void *data, bool reserved)
>  
>  static void nbd_clear_que(struct nbd_device *nbd)
>  {
> -	blk_mq_stop_hw_queues(nbd->disk->queue);
> +	blk_mq_quiesce_queue(nbd->disk->queue);
>  	blk_mq_tagset_busy_iter(&nbd->tag_set, nbd_clear_req, NULL);
> -	blk_mq_start_hw_queues(nbd->disk->queue);
> +	blk_mq_unquiesce_queue(nbd->disk->queue);
>  	dev_dbg(disk_to_dev(nbd->disk), "queue cleared\n");

Reviewed-by: Ming Lei <ming.lei at redhat.com>

-- 
Ming