[PATCH v2 1/3] block: simplify calling convention of elv_unregister_queue()

Eric Biggers
2021-11-30T04:05:26Z

From: Eric Biggers <ebiggers@google.com>

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.

Signed-off-by: Eric Biggers <ebiggers@google.com>
---
block/blk-sysfs.c | 3 +--
block/elevator.c | 8 ++++----
2 files changed, 5 insertions(+), 6 deletions(-)

diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c
index 4622da4bb9927..91d3805a6ec6b 100644
--- a/block/blk-sysfs.c
+++ b/block/blk-sysfs.c
@@ -957,8 +957,7 @@ 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);
disk_unregister_independent_access_ranges(disk);
mutex_unlock(&q->sysfs_lock);
mutex_unlock(&q->sysfs_dir_lock);
diff --git a/block/elevator.c b/block/elevator.c
index ec98aed39c4f5..b062c5bc10b9a 100644
--- a/block/elevator.c
+++ b/block/elevator.c
@@ -516,9 +516,11 @@ 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);
@@ -593,9 +595,7 @@ 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);
blk_mq_sched_free_rqs(q);
elevator_exit(q);
--
2.34.1