On 2021/09/07 17:10, Paolo Valente wrote:

quoted

Il giorno 2 set 2021, alle ore 15:31, yukuai (C) [off-list ref] ha scritto:

On 2021/08/27 1:00, Paolo Valente wrote:

quoted

Why do you make these extensive changes, while you can leave all the
function unchanged and just modify the above condition to something
like
|| bfqd->num_groups_with_pending_reqs > 1
|| (bfqd->num_groups_with_pending_reqs && bfqd->num_queues_with_pending_reqs_in_root)

Hi, Paolo

I was thinking that if CONFIG_BFQ_GROUP_IOSCHED is enabled, there is no
need to caculate smallest_weight, varied_queue_weights, and
multiple_classes_busy:

If we count root group into num_groups_with_pending_reqs
- If num_groups_with_pending_reqs <= 1, idle is not needed

Unfortunately, if active queues have different weights or belong to
different classes, then idling is needed to preserve per-queue
bandwidths.

Thanks,
Paolo

Hi, Paolo

It's right, if num_groups_with_pending_reqs == 1, multiple_classes_busy
should be checked, while smallest_weight and varied_queue_weights can
be skipped.

Thanks
Kuai

.