diff options
Diffstat (limited to 'block/blk-throttle.c')
| -rw-r--r-- | block/blk-throttle.c | 39 |
1 files changed, 35 insertions, 4 deletions
diff --git a/block/blk-throttle.c b/block/blk-throttle.c index 140da29f5800..c82bf9b1fe72 100644 --- a/block/blk-throttle.c +++ b/block/blk-throttle.c @@ -165,6 +165,10 @@ struct throtl_grp { unsigned long checked_last_finish_time; /* ns / 1024 */ unsigned long avg_idletime; /* ns / 1024 */ unsigned long idletime_threshold; /* us */ + + unsigned int bio_cnt; /* total bios */ + unsigned int bad_bio_cnt; /* bios exceeding latency threshold */ + unsigned long bio_cnt_reset_time; }; /* We measure latency for request size from <= 4k to >= 1M */ @@ -1720,12 +1724,15 @@ static bool throtl_tg_is_idle(struct throtl_grp *tg) * - single idle is too long, longer than a fixed value (in case user * configure a too big threshold) or 4 times of slice * - average think time is more than threshold + * - IO latency is largely below threshold */ unsigned long time = jiffies_to_usecs(4 * tg->td->throtl_slice); time = min_t(unsigned long, MAX_IDLE_TIME, time); return (ktime_get_ns() >> 10) - tg->last_finish_time > time || - tg->avg_idletime > tg->idletime_threshold; + tg->avg_idletime > tg->idletime_threshold || + (tg->latency_target && tg->bio_cnt && + tg->bad_bio_cnt * 5 < tg->bio_cnt); } static bool throtl_tg_can_upgrade(struct throtl_grp *tg) @@ -2194,12 +2201,36 @@ void blk_throtl_bio_endio(struct bio *bio) start_time = blk_stat_time(&bio->bi_issue_stat) >> 10; finish_time = __blk_stat_time(finish_time_ns) >> 10; + if (!start_time || finish_time <= start_time) + return; + + lat = finish_time - start_time; /* this is only for bio based driver */ - if (start_time && finish_time > start_time && - !(bio->bi_issue_stat.stat & SKIP_LATENCY)) { - lat = finish_time - start_time; + if (!(bio->bi_issue_stat.stat & SKIP_LATENCY)) throtl_track_latency(tg->td, blk_stat_size(&bio->bi_issue_stat), bio_op(bio), lat); + + if (tg->latency_target) { + int bucket; + unsigned int threshold; + + bucket = request_bucket_index( + blk_stat_size(&bio->bi_issue_stat)); + threshold = tg->td->avg_buckets[bucket].latency + + tg->latency_target; + if (lat > threshold) + tg->bad_bio_cnt++; + /* + * Not race free, could get wrong count, which means cgroups + * will be throttled + */ + tg->bio_cnt++; + } + + if (time_after(jiffies, tg->bio_cnt_reset_time) || tg->bio_cnt > 1024) { + tg->bio_cnt_reset_time = tg->td->throtl_slice + jiffies; + tg->bio_cnt /= 2; + tg->bad_bio_cnt /= 2; } } #endif |