@@ -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
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@huaweicloud.com> --- block/bfq-iosched.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-)