blk-cgroup: remove a dead check in blk_throtl_bio

bios must have a valid block group by the time they are submitted.

Signed-off-by: Christoph Hellwig <hch@lst.de>

diff --git a/block/blk-throttle.c b/block/blk-throttle.c
index 9d00f62c05ecdf1d621beaf3aa5c461219772add..ad37043297ed5898dd7e03b858d5aa8fd9f5a150 100644 (file)
--- a/block/blk-throttle.c
+++ b/block/blk-throttle.c
@@ -2163,7 +2163,7 @@ bool blk_throtl_bio(struct bio *bio)
        struct request_queue *q = bio->bi_disk->queue;
        struct blkcg_gq *blkg = bio->bi_blkg;
        struct throtl_qnode *qn = NULL;
-       struct throtl_grp *tg = blkg_to_tg(blkg ?: q->root_blkg);
+       struct throtl_grp *tg = blkg_to_tg(blkg);
        struct throtl_service_queue *sq;
        bool rw = bio_data_dir(bio);
        bool throttled = false;