[PATCH] mac80211: check ATF flag in ieee80211_next_txq()

[Ryder Lee]

On Wed, 2021-01-06 at 11:51 +0100, Toke Høiland-Jørgensen wrote:
> Ryder Lee <ryder.lee at mediatek.com> writes:
> 
> > The selected txq should be scheduled unconditionally if
> > NL80211_EXT_FEATURE_AIRTIME_FAIRNESS is not set by driver.
> >
> > Also put the sta to the end of the active_txqs list if
> > deficit is negative then move on to the next txq.
> 
> Why is this needed? If the feature is not set, no airtime should ever be
> accounted to the station, and so sta->airtime[txqi->txq.ac].deficit will
> always be 0 - so you're just adding another check that doesn't actually
> change the behaviour, aren't you?
> 
> -Toke

You're right. I think the problem is we still call
ieee80211_sta_register_airtime() in driver even if feature is not set,
and that makes deficit < 0. Will fix it in driver.

Ryder