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Subject: Re: [PATCH] mac80211: check ATF flag in ieee80211_next_txq()
To:     =?UTF-8?Q?Toke_H=c3=b8iland-J=c3=b8rgensen?= <toke@toke.dk>,
        Ryder Lee <ryder.lee@mediatek.com>
Cc:     Lorenzo Bianconi <lorenzo.bianconi@redhat.com>,
        Shayne Chen <shayne.chen@mediatek.com>,
        linux-wireless@vger.kernel.org, linux-mediatek@lists.infradead.org
References: <d9aef825d186a91ff91f6a81045d49d375533b14.1609894402.git.ryder.lee@mediatek.com>
 <87r1my49us.fsf@toke.dk>
From:   Felix Fietkau <nbd@nbd.name>
Message-ID: <68ab89bc-70f4-e822-3d96-21ba3bd6511f@nbd.name>
Date:   Wed, 6 Jan 2021 14:30:57 +0100
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On 2021-01-06 11:51, Toke Høiland-Jørgensen wrote:
> Ryder Lee <ryder.lee@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?
I think it might make sense to keep airtime reporting even when airtime
fairness is disabled at run time, so this patch makes sense to me.
Instead of this patch, the right place to deal with this would probably
be ieee80211_sta_register_airtime.

- Felix