block: Fake max open zones limit when there is no limit

For a zoned block device that has no limit on the number of open zones
and no limit on the number of active zones, the zone write plug mempool
is created with a size of 128 zone write plugs. For such case, set the
device max_open_zones queue limit to this value to indicate to the user
the potential performance penalty that may happen when writing
simultaneously to more zones than the mempool size.

Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Tested-by: Hans Holmberg <hans.holmberg@wdc.com>
Tested-by: Dennis Maisenbacher <dennis.maisenbacher@wdc.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20240408014128.205141-9-dlemoal@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Damien Le Moal 2024-04-08 10:41:08 +09:00 committed by Jens Axboe
parent dd291d77cc
commit 843283e96e

View File

@ -1503,6 +1503,38 @@ struct blk_revalidate_zone_args {
sector_t sector;
};
/*
* Update the disk zone resources information and device queue limits.
* The disk queue is frozen when this is executed.
*/
static int disk_update_zone_resources(struct gendisk *disk,
struct blk_revalidate_zone_args *args)
{
struct request_queue *q = disk->queue;
struct queue_limits lim;
disk->nr_zones = args->nr_zones;
disk->zone_capacity = args->zone_capacity;
swap(disk->seq_zones_wlock, args->seq_zones_wlock);
swap(disk->conv_zones_bitmap, args->conv_zones_bitmap);
/*
* If the device has no limit on the maximum number of open and active
* zones, set its max open zone limit to the mempool size to indicate
* to the user that there is a potential performance impact due to
* dynamic zone write plug allocation when simultaneously writing to
* more zones than the size of the mempool.
*/
if (disk->zone_wplugs_pool) {
lim = queue_limits_start_update(q);
if (!lim.max_open_zones && !lim.max_active_zones)
lim.max_open_zones = disk->zone_wplugs_pool->min_nr;
return queue_limits_commit_update(q, &lim);
}
return 0;
}
/*
* Helper function to check the validity of zones of a zoned block device.
*/
@ -1703,17 +1735,14 @@ int blk_revalidate_disk_zones(struct gendisk *disk,
*/
blk_mq_freeze_queue(q);
if (ret > 0) {
disk->nr_zones = args.nr_zones;
disk->zone_capacity = args.zone_capacity;
swap(disk->seq_zones_wlock, args.seq_zones_wlock);
swap(disk->conv_zones_bitmap, args.conv_zones_bitmap);
ret = disk_update_zone_resources(disk, &args);
if (update_driver_data)
update_driver_data(disk);
ret = 0;
} else {
pr_warn("%s: failed to revalidate zones\n", disk->disk_name);
disk_free_zone_resources(disk);
}
if (ret)
disk_free_zone_resources(disk);
blk_mq_unfreeze_queue(q);
kfree(args.seq_zones_wlock);