Re: [PATCH RFC v4 3/4] mac80211: Add airtime accounting and scheduling to TXQs

[Rajkumar Manoharan <rmanohar@codeaurora.org>]

On 2018-09-16 10:42, Toke Høiland-Jørgensen wrote:
> This adds airtime accounting and scheduling to the mac80211 TXQ
> scheduler. A new callback, ieee80211_sta_register_airtime(), is added
> that drivers can call to report airtime usage for stations.
> 
> +bool ieee80211_txq_may_transmit(struct ieee80211_hw *hw,
> +				struct ieee80211_txq *txq)
> +{

[...]

> +	if (ret) {
> +		clear_bit(IEEE80211_TXQ_AIRTIME_THROTTLE, &txqi->flags);
> +		list_del_init(&txqi->schedule_order);
> +	} else
> +		set_bit(IEEE80211_TXQ_AIRTIME_THROTTLE, &txqi->flags);
> +
> 
This looks wrong to me. txqi->flags are protected by fq->lock but here
it is by active_txq_lock. no?

> @@ -3677,6 +3751,7 @@ void ieee80211_txq_schedule_end(struct
> ieee80211_hw *hw, u8 ac)
>  	struct ieee80211_local *local = hw_to_local(hw);
> 
>  	spin_unlock_bh(&local->active_txq_lock[ac]);
> +	tasklet_schedule(&local->wake_txqs_tasklet);
>  }
> 
It is an overload to schedule wake_txqs_tasklet for each txq unlock.
Instead I would prefer to call __ieee80211_kick_airtime from 
schedule_end.
Thoughts?

-Rajkumar