From f753526e327bc849c445c084d0f374e992038ae9 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 21 Sep 2022 20:04:49 +0200 Subject: blk-cgroup: remove blkg_lookup_check The combinations of an error check with an ERR_PTR return and a lookup with a NULL return leads to ugly handling of the return values in the callers. Just open coding the check and the lookup is much simpler. Signed-off-by: Christoph Hellwig Reviewed-by: Andreas Herrmann Acked-by: Tejun Heo Link: https://lore.kernel.org/r/20220921180501.1539876-6-hch@lst.de Signed-off-by: Jens Axboe --- block/blk-cgroup.c | 36 ++++++++++-------------------------- 1 file changed, 10 insertions(+), 26 deletions(-) diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index d1216760d025..1306112d7648 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -602,25 +602,6 @@ u64 __blkg_prfill_u64(struct seq_file *sf, struct blkg_policy_data *pd, u64 v) } EXPORT_SYMBOL_GPL(__blkg_prfill_u64); -/* Performs queue bypass and policy enabled checks then looks up blkg. */ -static struct blkcg_gq *blkg_lookup_check(struct blkcg *blkcg, - const struct blkcg_policy *pol, - struct request_queue *q) -{ - struct blkcg_gq *blkg; - - WARN_ON_ONCE(!rcu_read_lock_held()); - lockdep_assert_held(&q->queue_lock); - - if (!blkcg_policy_enabled(q, pol)) - return ERR_PTR(-EOPNOTSUPP); - - blkg = blkg_lookup(blkcg, q); - if (blkg) - blkg_update_hint(blkcg, blkg); - return blkg; -} - /** * blkcg_conf_open_bdev - parse and open bdev for per-blkg config update * @inputp: input string pointer @@ -697,14 +678,16 @@ int blkg_conf_prep(struct blkcg *blkcg, const struct blkcg_policy *pol, rcu_read_lock(); spin_lock_irq(&q->queue_lock); - blkg = blkg_lookup_check(blkcg, pol, q); - if (IS_ERR(blkg)) { - ret = PTR_ERR(blkg); + if (!blkcg_policy_enabled(q, pol)) { + ret = -EOPNOTSUPP; goto fail_unlock; } - if (blkg) + blkg = blkg_lookup(blkcg, q); + if (blkg) { + blkg_update_hint(blkcg, blkg); goto success; + } /* * Create blkgs walking down from blkcg_root to @blkcg, so that all @@ -740,14 +723,15 @@ int blkg_conf_prep(struct blkcg *blkcg, const struct blkcg_policy *pol, rcu_read_lock(); spin_lock_irq(&q->queue_lock); - blkg = blkg_lookup_check(pos, pol, q); - if (IS_ERR(blkg)) { - ret = PTR_ERR(blkg); + if (!blkcg_policy_enabled(q, pol)) { blkg_free(new_blkg); + ret = -EOPNOTSUPP; goto fail_preloaded; } + blkg = blkg_lookup(pos, q); if (blkg) { + blkg_update_hint(pos, blkg); blkg_free(new_blkg); } else { blkg = blkg_create(pos, q, new_blkg); -- cgit v1.2.3-59-g8ed1b