From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from sipsolutions.net (s3.sipsolutions.net [IPv6:2a01:4f8:191:4433::2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id A00AE3CB35 for ; Tue, 11 Sep 2018 05:20:18 -0400 (EDT) Received: by sipsolutions.net with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.91) (envelope-from ) id 1fzeqE-0008Pb-4n; Tue, 11 Sep 2018 11:20:14 +0200 Message-ID: <1536657605.3224.122.camel@sipsolutions.net> From: Johannes Berg To: Toke =?ISO-8859-1?Q?H=F8iland-J=F8rgensen?= , linux-wireless@vger.kernel.org, make-wifi-fast@lists.bufferbloat.net Cc: Rajkumar Manoharan , Felix Fietkau Date: Tue, 11 Sep 2018 11:20:05 +0200 In-Reply-To: <87muspjt38.fsf@toke.dk> References: <153635803319.14170.10011969968767927187.stgit@alrua-x1> <153635897010.14170.2992498632345986102.stgit@alrua-x1> <1536565717.3224.12.camel@sipsolutions.net> <87musplivy.fsf@toke.dk> <1536577419.3224.50.camel@sipsolutions.net> <87zhwpjzme.fsf@toke.dk> <1536583587.3224.71.camel@sipsolutions.net> <87wortjy8n.fsf@toke.dk> <1536585051.3224.72.camel@sipsolutions.net> <87r2i1jxse.fsf@toke.dk> <1536591110.3224.76.camel@sipsolutions.net> <87muspjt38.fsf@toke.dk> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.26.6 (3.26.6-1.fc27) Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Subject: Re: [Make-wifi-fast] [PATCH RFC v3 1/4] mac80211: Add TXQ scheduling API 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: Tue, 11 Sep 2018 09:20:18 -0000 On Mon, 2018-09-10 at 17:00 +0200, Toke Høiland-Jørgensen wrote: > > Do we even need end_schedule()? It's hard to pass multiple things to a > > single call (do you build a list?), so having > > > > start_schedule(), get_txq(), return_txq() > > > > would be sufficient? > > Well, start_schedule() / end_schedule() would be needed if we are going > to add locking in mac80211? [...] > If we decide mac80211 needs to do locking to prevent two threads from > scheduling the same ac, that would also be needed for the hw-managed > case? Yes, good point. > > It seems like not? Basically it seems to me that in the hw-managed > > case all you need is may_tx()? And in fact, once you opt in you don't > > even really need *that* since mac80211 can just return NULL from > > get_skb()? > > Yeah, we could just throttle in get_skb(); the separate call was to > avoid the overhead of the check for every packet. Typically, you'll pick > a TXQ, then dequeue multiple packets from it in succession; with a > separate call to may_tx(), you only do the check once, not for every > packet... Yeah, also a good point. Still, txq = get_txq(txq) doesn't feel right, so better to keep that separate I think. johannes