blk-cgroup: cleanup blkcg_maybe_throttle_current

Use blkcg_css instead of opencoding it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20220420042723.1010598-15-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index 5684a8c..a91f8ae 100644 (file)
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -1808,7 +1808,6 @@ static void blkcg_maybe_throttle_blkg(struct blkcg_gq *blkg, bool use_memdelay)
 void blkcg_maybe_throttle_current(void)
 {
        struct request_queue *q = current->throttle_queue;
-       struct cgroup_subsys_state *css;
        struct blkcg *blkcg;
        struct blkcg_gq *blkg;
        bool use_memdelay = current->use_memdelay;
@@ -1820,12 +1819,7 @@ void blkcg_maybe_throttle_current(void)
        current->use_memdelay = false;
 
        rcu_read_lock();
-       css = kthread_blkcg();
-       if (css)
-               blkcg = css_to_blkcg(css);
-       else
-               blkcg = css_to_blkcg(task_css(current, io_cgrp_id));
-
+       blkcg = css_to_blkcg(blkcg_css());
        if (!blkcg)
                goto out;
        blkg = blkg_lookup(blkcg, q);