blk-cgroup: simplify blkg freeing from initialization failure paths

There is no need to delay freeing a blkg to a workqueue when freeing it
after an initialization failure.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Acked-by: NTejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20230203150400.3199230-5-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

block/blk-cgroup.c

@@ -114,10 +114,8 @@ static bool blkcg_policy_enabled(struct request_queue *q,
 	return pol && test_bit(pol->plid, q->blkcg_pols);
 }
 
-static void blkg_free_workfn(struct work_struct *work)
+static void blkg_free(struct blkcg_gq *blkg)
 {
-	struct blkcg_gq *blkg = container_of(work, struct blkcg_gq,
-					     free_work);
 	struct request_queue *q = blkg->q;
 	int i;
 
@@ -143,23 +141,9 @@ static void blkg_free_workfn(struct work_struct *work)
 	kfree(blkg);
 }
 
-/**
- * blkg_free - free a blkg
- * @blkg: blkg to free
- *
- * Free @blkg which may be partially allocated.
- */
-static void blkg_free(struct blkcg_gq *blkg)
+static void blkg_free_workfn(struct work_struct *work)
 {
-	if (!blkg)
-		return;
-
-	/*
-	 * Both ->pd_free_fn() and request queue's release handler may
-	 * sleep, so free us by scheduling one work func
-	 */
-	INIT_WORK(&blkg->free_work, blkg_free_workfn);
-	schedule_work(&blkg->free_work);
+	blkg_free(container_of(work, struct blkcg_gq, free_work));
 }
 
 static void __blkg_release(struct rcu_head *rcu)
@@ -170,7 +154,10 @@ static void __blkg_release(struct rcu_head *rcu)
 
 	/* release the blkcg and parent blkg refs this blkg has been holding */
 	css_put(&blkg->blkcg->css);
-	blkg_free(blkg);
+
+	/* ->pd_free_fn() may sleep, so free from a work queue */
+	INIT_WORK(&blkg->free_work, blkg_free_workfn);
+	schedule_work(&blkg->free_work);
 }
 
 /*