When only io.max is in use, tg->target_latency is set to the default
value, if that's the case, bad_bio_cnt is not checking at all, so it
makes no sense to check latency and do bad_bio_cnt counting in
blk_throtl_bio_endio().
Signed-off-by: Liu Bo <bo....@linux.alibaba.com>
---
block/blk-throttle.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/block/blk-throttle.c b/block/blk-throttle.c
index 03b63d9aa756..4ac552850686 100644
--- a/block/blk-throttle.c
+++ b/block/blk-throttle.c
@@ -2338,6 +2338,10 @@ void blk_throtl_bio_endio(struct bio *bio)
throtl_track_latency(tg->td, bio_issue_size(&bio->bi_issue),
bio_op(bio), lat);
+ /* Skip bad bio counting if latency_target is not set. */
+ if (tg->latency_target == DFL_LATENCY_TARGET)
+ goto out;
+
if (tg->latency_target && lat >= tg->td->filtered_latency) {
int bucket;
unsigned int threshold;
@@ -2362,6 +2366,7 @@ void blk_throtl_bio_endio(struct bio *bio)
tg->bad_bio_cnt /= 2;
}
+out:
blkg_put(tg_to_blkg(tg));
}
#endif
--
1.8.3.1
