Kan Yan [off-list ref] writes:

Hi Toke,

It is great to see finally there will be a general airtime fairness
support in mac80211. I feel this patch set could still use some
improvements to make it works better with 11ac drivers like ath10k. I
did a version of airtime fairness in the ath10k driver that used in
Google Wifi and I'd like to share a few things I learned from this
experience.

Hi Kan

Thanks for weighing in!

The idea is to use airtime accounting to give firmware just enough
frames to keep it busy and form good aggregations, and keeps the rest
of frames in mac80211 layer queues so Fq_Codel can work on it to
control latency.

I think this is a great approach, that we should definitely adopt in
mac80211. However, I'm not sure the outstanding airtime limiting should
be integrated into the fairness scheduling, since there are drivers such
as ath9k that don't need it.

Rather, I'd propose that we figure out the API for fairness scheduling
first, and add the BQL-like limiter as a separate layer. They can be
integrated in the sense that the limiter's estimate of airtime can be
used for fairness scheduling as well in the case where the
driver/firmware doesn't have a better source of airtime usage.

Does that make sense?

-Toke