Commit 178fa7d4 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Jens Axboe
Browse files

blk-cgroup: delay blk-cgroup initialization until add_disk 



There is no need to initialize the cgroup code before the disk is marked
live.  Moving the cgroup initialization earlier will help to have a
fully initialized struct device in the gendisk for the cgroup code to
use in the future.  Similarly tear the cgroup information down in
del_gendisk to be symmetric and because none of the cgroup tracking is
needed once non-passthrough I/O stops.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarAndreas Herrmann <aherrmann@suse.de>
Acked-by: default avatarTejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20230203150400.3199230-3-hch@lst.de


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent a886001c

block/genhd.c

+9 −8
Original line number Diff line number Diff line
@@ -466,10 +466,14 @@ int __must_check device_add_disk(struct device *parent, struct gendisk *disk, 
	 */

	pm_runtime_set_memalloc_noio(ddev, true);



	ret = blk_integrity_add(disk);

	ret = blkcg_init_disk(disk);

	if (ret)

		goto out_del_block_link;



	ret = blk_integrity_add(disk);

	if (ret)

		goto out_blkcg_exit;



	disk->part0->bd_holder_dir =

		kobject_create_and_add("holders", &ddev->kobj);

	if (!disk->part0->bd_holder_dir) {
@@ -534,6 +538,8 @@ int __must_check device_add_disk(struct device *parent, struct gendisk *disk, 
	kobject_put(disk->part0->bd_holder_dir);

out_del_integrity:

	blk_integrity_del(disk);

out_blkcg_exit:

	blkcg_exit_disk(disk);

out_del_block_link:

	if (!sysfs_deprecated)

		sysfs_remove_link(block_depr, dev_name(ddev));
@@ -662,6 +668,8 @@ void del_gendisk(struct gendisk *disk) 
	rq_qos_exit(q);

	blk_mq_unquiesce_queue(q);



	blkcg_exit_disk(disk);



	/*

	 * If the disk does not own the queue, allow using passthrough requests

	 * again.  Else leave the queue frozen to fail all I/O.
@@ -1171,8 +1179,6 @@ static void disk_release(struct device *dev) 
	    !test_bit(GD_ADDED, &disk->state))

		blk_mq_exit_queue(disk->queue);



	blkcg_exit_disk(disk);



	bioset_exit(&disk->bio_split);



	disk_release_events(disk);
@@ -1385,9 +1391,6 @@ struct gendisk *__alloc_disk_node(struct request_queue *q, int node_id, 
	if (xa_insert(&disk->part_tbl, 0, disk->part0, GFP_KERNEL))

		goto out_destroy_part_tbl;



	if (blkcg_init_disk(disk))

		goto out_erase_part0;



	rand_initialize_disk(disk);

	disk_to_dev(disk)->class = &block_class;

	disk_to_dev(disk)->type = &disk_type;
@@ -1400,8 +1403,6 @@ struct gendisk *__alloc_disk_node(struct request_queue *q, int node_id, 
#endif

	return disk;



out_erase_part0:

	xa_erase(&disk->part_tbl, 0);

out_destroy_part_tbl:

	xa_destroy(&disk->part_tbl);

	disk->part0->bd_disk = NULL;