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From:   Toke =?utf-8?Q?H=C3=B8iland-J=C3=B8rgensen?= <toke@redhat.com>
To:     Yibo Zhao <yiboz@codeaurora.org>
Cc:     linux-wireless@vger.kernel.org, ath10k@lists.infradead.org,
        linux-wireless-owner@vger.kernel.org
Subject: Re: [PATCH V3 4/4] mac80211: Sync airtime weight sum with per AC synced sta airtime weight together
In-Reply-To: <ffe79f35d4dcb50aa31dc04035855f79@codeaurora.org>
References: <1569223201-1490-1-git-send-email-yiboz@codeaurora.org> <1569223201-1490-5-git-send-email-yiboz@codeaurora.org> <87blvb5lb9.fsf@toke.dk> <ffe79f35d4dcb50aa31dc04035855f79@codeaurora.org>
Date:   Tue, 24 Sep 2019 09:27:16 +0200
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Yibo Zhao <yiboz@codeaurora.org> writes:

> On 2019-09-23 19:00, Toke H=C3=B8iland-J=C3=B8rgensen wrote:
>
>>> -=09if (params->airtime_weight)
>>> -=09=09sta->airtime_weight =3D params->airtime_weight;
>>> +=09if (params->airtime_weight &&
>>> +=09    params->airtime_weight !=3D sta->airtime_weight) {
>>=20
>> This check doesn't work I think? You're not using the array-based
>> sta->airtime_weight[], and there are locking issues by just checking
>> like this; so maybe just keep the if() on params->airtime_weight, and=20
>> do
>> the checking inside the loop while holding the lock?
>
> It should be array-based sta->airtime_weight[] and I am missing that=20
> part during the porting. But you are right about we should check it=20
> inside the loop with the lock.
>
>>=20
>> Or could we just turn the weights into atomics to avoid the locking
>> entirely?
>
> Actually, we still need the active txq locking to make sure the txq is=20
> on the rbtree. Otherwise, no need to change airtime weight sum.

True. Just moving the check inside the locking will be the right thing
to do, then.

-Toke