If BLK_DEV_THROTTLING is enabled, bio->bi_blkg shouldn't be NULL, so
warn if it is found as NULL, then return false and bypass throttling.
It helps Mike to figure out one dm-raid problem.
Cc: Mike Snitzer <snitzer@xxxxxxxxxx>
Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx>
---
block/blk-throttle.h | 3 +++
1 file changed, 3 insertions(+)
diff --git a/block/blk-throttle.h b/block/blk-throttle.h
index c1b602996127..55e93b3f3205 100644
--- a/block/blk-throttle.h
+++ b/block/blk-throttle.h
@@ -174,6 +174,9 @@ static inline bool blk_throtl_bio(struct bio *bio)
{
struct throtl_grp *tg = blkg_to_tg(bio->bi_blkg);
+ if (WARN_ON_ONCE(!tg))
+ return false;
+
/* no need to throttle bps any more if the bio has been throttled */
if (bio_flagged(bio, BIO_THROTTLED) &&
!(tg->flags & THROTL_TG_HAS_IOPS_LIMIT))
--
2.31.1
