[PATCH 6.1 51/71] elevator: add new field flags in struct elevator_queue

[Sasha Levin]

From: Yu Kuai <yukuai3@xxxxxxxxxx>

[ Upstream commit 181d06637451b5348d746039478e71fa53dfbff6 ]

There are only one flag to indicate that elevator is registered currently,
prepare to add a flag to disable wbt if default elevator is bfq.

Signed-off-by: Yu Kuai <yukuai3@xxxxxxxxxx>
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
Link: https://lore.kernel.org/r/20221019121518.3865235-6-yukuai1@xxxxxxxxxxxxxxx
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
Stable-dep-of: f814bdda774c ("blk-wbt: Fix detection of dirty-throttled tasks")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 block/elevator.c | 6 ++----
 block/elevator.h | 4 +++-
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/block/elevator.c b/block/elevator.c
index 20e70fd3f77f9..9e12706e8d8cb 100644
--- a/block/elevator.c
+++ b/block/elevator.c
@@ -512,7 +512,7 @@ int elv_register_queue(struct request_queue *q, bool uevent)
 		if (uevent)
 			kobject_uevent(&e->kobj, KOBJ_ADD);
 
-		e->registered = 1;
+		set_bit(ELEVATOR_FLAG_REGISTERED, &e->flags);
 	}
 	return error;
 }
@@ -523,11 +523,9 @@ void elv_unregister_queue(struct request_queue *q)
 
 	lockdep_assert_held(&q->sysfs_lock);
 
-	if (e && e->registered) {
+	if (e && test_and_clear_bit(ELEVATOR_FLAG_REGISTERED, &e->flags)) {
 		kobject_uevent(&e->kobj, KOBJ_REMOVE);
 		kobject_del(&e->kobj);
-
-		e->registered = 0;
 	}
 }
 
diff --git a/block/elevator.h b/block/elevator.h
index 3f0593b3bf9d3..ed574bf3e629e 100644
--- a/block/elevator.h
+++ b/block/elevator.h
@@ -100,10 +100,12 @@ struct elevator_queue
 	void *elevator_data;
 	struct kobject kobj;
 	struct mutex sysfs_lock;
-	unsigned int registered:1;
+	unsigned long flags;
 	DECLARE_HASHTABLE(hash, ELV_HASH_BITS);
 };
 
+#define ELEVATOR_FLAG_REGISTERED 0
+
 /*
  * block elevator interface
  */
-- 
2.43.0