BACKPORT: block: simplify calling convention of elv_unregister_queue()

Make elv_unregister_queue() a no-op if q->elevator is NULL or is not
registered.

This simplifies the existing callers, as well as the future caller in
the error path of blk_register_queue().

Also don't bother checking whether q is NULL, since it never is.

Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220124215938.2769-2-ebiggers@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>

(cherry picked from commit f5ec592dd3bcf7c91f7c262a7f5011e001d269cd)

Conflicts:
	block/blk-sysfs.c

Bug: 207390665
Change-Id: I9e4226b7241755ca22dd9687b084e0077885d222
Signed-off-by: Eric Biggers <ebiggers@google.com>
This commit is contained in:
Eric Biggers
2022-01-24 13:59:36 -08:00
committed by Jaegeuk Kim
parent 193b27f6e3
commit 06bbdfd28a
2 changed files with 5 additions and 6 deletions

View File

@@ -970,8 +970,7 @@ void blk_unregister_queue(struct gendisk *disk)
blk_trace_remove_sysfs(disk_to_dev(disk));
mutex_lock(&q->sysfs_lock);
if (q->elevator)
elv_unregister_queue(q);
elv_unregister_queue(q);
mutex_unlock(&q->sysfs_lock);
mutex_unlock(&q->sysfs_dir_lock);

View File

@@ -514,9 +514,11 @@ int elv_register_queue(struct request_queue *q, bool uevent)
void elv_unregister_queue(struct request_queue *q)
{
struct elevator_queue *e = q->elevator;
lockdep_assert_held(&q->sysfs_lock);
if (q) {
if (e && e->registered) {
struct elevator_queue *e = q->elevator;
kobject_uevent(&e->kobj, KOBJ_REMOVE);
@@ -591,9 +593,7 @@ int elevator_switch_mq(struct request_queue *q,
lockdep_assert_held(&q->sysfs_lock);
if (q->elevator) {
if (q->elevator->registered)
elv_unregister_queue(q);
elv_unregister_queue(q);
ioc_clear_queue(q);
elevator_exit(q, q->elevator);
}