From: Yu Kuai <yukuai3@xxxxxxxxxx> In this special case, there is no need to throttle io. Signed-off-by: Yu Kuai <yukuai3@xxxxxxxxxx> --- block/blk-iocost.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/block/blk-iocost.c b/block/blk-iocost.c index 5acc5f13bbd6..32e7e416d67c 100644 --- a/block/blk-iocost.c +++ b/block/blk-iocost.c @@ -2564,8 +2564,13 @@ static void ioc_rqos_throttle(struct rq_qos *rqos, struct bio *bio) bool use_debt, ioc_locked; unsigned long flags; - /* bypass IOs if disabled, still initializing, or for root cgroup */ - if (!ioc->enabled || !iocg || !iocg->level) + /* + * bypass IOs if disabled, still initializing, for root cgroup, + * or the cgroup is the only cgroup with io. + */ + if (!ioc->enabled || !iocg || !iocg->level || + (iocg->hweight_inuse == WEIGHT_ONE && + atomic_read(&ioc->hweight_gen) == iocg->hweight_gen)) return; /* calculate the absolute vtime cost */ -- 2.31.1
