If budget left is less than budget need by next request, the activated bfqq will be expired if it preempts the in-service queue. Avoid to cause useless overhead to check budget left is enough for next request. Signed-off-by: Kemeng Shi <shikemeng@xxxxxxxxxxxxxxx> --- block/bfq-iosched.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c index 7b416f9471b3..edbf5c9aeb47 100644 --- a/block/bfq-iosched.c +++ b/block/bfq-iosched.c @@ -1588,13 +1588,15 @@ static bool bfq_bfqq_update_budg_for_activation(struct bfq_data *bfqd, /* * In the next compound condition, we check also whether there - * is some budget left, because otherwise there is no point in - * trying to go on serving bfqq with this same budget: bfqq - * would be expired immediately after being selected for - * service. This would only cause useless overhead. + * is some budget left for next request to serve, because + * otherwise there is no point in trying to go on serving bfqq + * with this same budget: bfqq would be expired immediately + * after being selected for service. This would only cause + * useless overhead. */ if (bfq_bfqq_non_blocking_wait_rq(bfqq) && arrived_in_time && - bfq_bfqq_budget_left(bfqq) > 0) { + bfq_bfqq_budget_left(bfqq) >= + bfq_serv_to_charge(bfqq->next_rq, bfqq)) { /* * We do not clear the flag non_blocking_wait_rq here, as * the latter is used in bfq_activate_bfqq to signal -- 2.30.0