From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.toke.dk (mail.toke.dk [52.28.52.200]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id 5E51F3BA8E for ; Wed, 29 Aug 2018 05:27:15 -0400 (EDT) From: Toke =?utf-8?Q?H=C3=B8iland-J=C3=B8rgensen?= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=toke.dk; s=20161023; t=1535534834; bh=VOuQwI0FnNoDmVHoQV79+pFdeFo+kD+Q8tuAp5UFosY=; h=From:To:Cc:Subject:In-Reply-To:References:Date:From; b=My/Pl6NeZdJGSq8ahHT1d7FwnXofxdNI/zvskGhAz0PcJtHiNFQMzBD/IvplZsmRt KLV4IeO7QsnC+Kv4AdFv7StQY/Q1vWH35mjQzmTUYi3H//SoVU7OO2UHF0Wu1p4uAr tKGY8ZTDP7sJgHUAxRiJCpds2odOb6qD0mbTBw79tW1mBPLYArAkKzjrSyL0O+El5t j1bilgbq2KUwJ/nEYxdS1FsvNoQ6ykiU3RI7jmdAvEb6FSW8j1h1JS/MuxFBqlv5We yKbYj/Op27TgihNTRmaO/fnCyjGSvvJyTSCJ5HwVF6GiSFyw8iA5bg38hrI/N251fe TjGOiylf02wXg== To: Johannes Berg , linux-wireless@vger.kernel.org Cc: make-wifi-fast@lists.bufferbloat.net, Felix Fietkau In-Reply-To: <1535528658.5215.19.camel@sipsolutions.net> References: <153115421866.7447.6363834356268564403.stgit@alrua-x1> <153115422499.7447.2570671473822724496.stgit@alrua-x1> <1535528658.5215.19.camel@sipsolutions.net> Date: Wed, 29 Aug 2018 11:27:13 +0200 X-Clacks-Overhead: GNU Terry Pratchett Message-ID: <877ek94j66.fsf@toke.dk> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Subject: Re: [Make-wifi-fast] [RFC v2 2/4] mac80211: Add airtime accounting and scheduling to TXQs X-BeenThere: make-wifi-fast@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 29 Aug 2018 09:27:15 -0000 Johannes Berg writes: > On Mon, 2018-07-09 at 18:37 +0200, Toke H=C3=B8iland-J=C3=B8rgensen wrote: >>=20 >> @@ -427,6 +428,8 @@ struct sta_info *sta_info_alloc(struct ieee80211_sub= _if_data *sdata, >> sta->cparams.interval =3D MS2TIME(100); >> sta->cparams.ecn =3D true; >>=20=20 >> + sta->airtime.weight =3D 1; > > Perhaps it might be useful to start with a higher default (even > something like 1<<8) as that would allow adjusting up/down single > stations, without having to adjust all stations and listening to new > additions to adjust them quickly etc? > > Theoretically this doesn't really matter, but from a practical POV it > may be easier to leave them all at the default and just adjust the ones > that need adjustment for some reason. Hmm, the problem with a higher weight is that weight*quantum becomes the time each station is scheduled, so having a higher value means higher latency. This could be fixed by replacing the station weights with per-station quantums, but I felt that this was exposing an implementation detail in the API; if we ever change the enforcement mechanism to not be quantum-based (as may be necessary for MU-MIMO for instance), we'll have to convert values in the kernel. Whereas weights are a conceptual measure that is not tied to any particular implementation. >> ieee80211_sta_register_airtime > > Do we really need this? We already have at least TX status with > airtime, for ieee80211_sta_tx_notify() and friends, and the station > pointer in that context, so couldn't we piggy-back on this? At least > WMM-AC already requires the driver to provide this. For the drivers that get airtime as part of TX completion, sure; but as I understand it, at least ath10k gets airtime information in out of band status reports, so there would need to be a callback for that in any case... -Toke