[PATCH 3/4] blk-throttle: Avoid tracking latency if low limit is invalid
From: Baolin Wang <baolin.wang@linux.alibaba.com>
Date: 2020-09-20 09:14:34
Also in:
cgroups, lkml
Subsystem:
block layer, control group - block io controller (blkio), the rest · Maintainers:
Jens Axboe, Tejun Heo, Josef Bacik, Linus Torvalds
The IO latency tracking is only for LOW limit, so we should add a validation to avoid redundant latency tracking if the LOW limit is not valid. Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> --- block/blk-throttle.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/block/blk-throttle.c b/block/blk-throttle.c
index 7e72102..b0d8f7c 100644
--- a/block/blk-throttle.c
+++ b/block/blk-throttle.c@@ -2100,7 +2100,7 @@ static void throtl_update_latency_buckets(struct throtl_data *td) unsigned long last_latency[2] = { 0 }; unsigned long latency[2]; - if (!blk_queue_nonrot(td->queue)) + if (!blk_queue_nonrot(td->queue) || !td->limit_valid[LIMIT_LOW]) return; if (time_before(jiffies, td->last_calculate_time + HZ)) return;
@@ -2338,6 +2338,8 @@ void blk_throtl_bio_endio(struct bio *bio) if (!blkg) return; tg = blkg_to_tg(blkg); + if (!tg->td->limit_valid[LIMIT_LOW]) + return; finish_time_ns = ktime_get_ns(); tg->last_finish_time = finish_time_ns >> 10;
--
1.8.3.1