On Mon, 2017-09-25 at 15:14 +0900, Damien Le Moal wrote:
> Modify mq-dealine init_queue and exit_queue elevator methods to handle
^^^^^^^^^^
mq-deadline ?
> +static int deadline_init_zones_wlock(struct request_queue *q,
> + struct deadline_data *dd)
> +{
> + /*
> + * For regular drives or non-conforming zoned block device,
> + * do not use zone write locking.
> + */
> + if (!blk_queue_nr_zones(q))
> + return 0;
> +
> + /*
> + * Treat host aware drives as regular disks.
> + */
> + if (blk_queue_zoned_model(q) != BLK_ZONED_HM)
> + return 0;
> +
> + dd->zones_wlock = kzalloc_node(BITS_TO_LONGS(blk_queue_nr_zones(q))
> + * sizeof(unsigned long),
> + GFP_KERNEL, q->node);
A request queue is created before disk validation occurs and before the
number of zones is initialized (sd_probe_async()). If a scheduler is
assigned to a ZBC drive through a udev rule, can it happen that
deadline_init_zones_wlock() is called before the number of zones has been
initialized?
Bart.
