From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.toke.dk (mail.toke.dk [IPv6:2001:470:dc45:1000::1]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id 4BD2E3CB35 for ; Wed, 3 Oct 2018 04:41:19 -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=1538556077; bh=XelobgcAyHyNTIb7hBc/SCUKZ2qrU4b5tBJr0Fqe5Ig=; h=From:To:Cc:Subject:In-Reply-To:References:Date:From; b=n2+DPPfCs9h8hgljoYtu69JBwoXgp4FdlhwmVusIVFy03b4DKb4mn1vf41L9lkiiB wzO+72gURrhKHiCq5iR8a0HWqSqWPCkEv23vU86Hh5qi6wbvAYDPGereQaC6msZ0N1 QqKrO0S8yX09wTnORFJGob/OXU6BfFJVvpi/Z7q37HGl1qduknnqJMQo/EsAtNOr+1 qvkA/GYEtt9mrudx1nSL0YuuS5mgo6pEoPAxoO/O2dv51qkWzdSFCoIDfmZ2PNPRJL CuaoD8FHXb3/l7K/96z3Fiui4UGX20uJdZ8QMVNy6Q8A5lvfRz28F2bbrQl0S06HKP C7quJJsckB6Sw== To: Rajkumar Manoharan Cc: Jonathan Morton , Kan Yan , make-wifi-fast@lists.bufferbloat.net, linux-wireless-owner@vger.kernel.org, linux-wireless@vger.kernel.org, Felix Fietkau In-Reply-To: <08dabe69e625c11f70b217ae9695c7f4@codeaurora.org> References: <153711966150.9231.13481453399723518107.stgit@alrua-x1> <153711973134.9231.18038849900399644494.stgit@alrua-x1.karlstad.toke.dk> <826b6251746ee4d280d532f4ecdc5aa3@codeaurora.org> <87pnx0haud.fsf@toke.dk> <8f7145bf5abe50194bced025a5e739b9@codeaurora.org> <863bc54fbf04441d38dd53f523300a7e@codeaurora.org> <93015743-5D16-4D79-948F-E2F46CF2450A@toke.dk> <7ba8513b0ec5a7c35b396c7739fc2d7d@codeaurora.org> <87zhw2eyfo.fsf@toke.dk> <5d961a5f61de45b85b1b037bcef9270d@codeaurora.org> <44B09168-C08F-4C85-8D74-D576CCC79880@gmail.com> <586459da6ec36edc2284df8533915d62@codeaurora.org> <4929C006-3452-4C17-9500-8D7485EB538E@toke.dk> <0531def170ef7f9cadcf85a6dc9af22b@codeaurora.org> <87a7nwbvwu.fsf@toke.dk> <877ej0b2d8.fsf@toke.dk> <30cf3754fa970aa1af11791c2625a7c9@codeaurora.org> <08dabe69e625c11f70b217ae9695c7f4@codeaurora.org> Date: Wed, 03 Oct 2018 10:41:16 +0200 X-Clacks-Overhead: GNU Terry Pratchett Message-ID: <87d0sre82b.fsf@toke.dk> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Subject: Re: [Make-wifi-fast] [PATCH RFC v4 3/4] 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, 03 Oct 2018 08:41:19 -0000 Rajkumar Manoharan writes: > On 2018-10-02 16:07, Rajkumar Manoharan wrote: >> On 2018-10-02 12:00, Toke H=C3=B8iland-J=C3=B8rgensen wrote: >>> Rajkumar Manoharan writes: >>>> I noticed a race condition b/w sta cleanup and kick_airtime tasklet. >>>>>> How do you plan to exit kick_airtime gracefully during sta_cleanup? >>>>>=20 >>>>> Ah, right, there's a lot of stuff going on before we get to=20 >>>>> purge_txq. >>>>> Hmm, I guess we should either make sure we remove the station from >>>>> active_txqs earlier in the sta cleanup process, or maybe it'd enough= =20 >>>>> to >>>>> just check the removed flag in the tasklet? >>>>>=20 >>>>> Does the below patch fix the issue? >>>>>=20 >>>>=20 >>>> No. Attaching backtrace. Any clue? >>>=20 >>> Ah, that's my bad. Just having a 'continue' there can make the=20 >>> function >>> loop forever. Oops. Try something like this instead? >>>=20 >>=20 >> But 'continue' also used in other places. Will give a try but I think=20 >> that >> calling drv_wake_tx_queue within iteration is dangerous as it alters >> the list. no? >>=20 > How about below change? Just schedule first txq and remaining will be > scheduled later by driver upon tx-compl. Your mail client seems to be mangling the patch somewhat, but I think I see what your intention is. And yeah, just waking a single TXQ and letting TX-completion do the rest is a good idea; will fold that into the next version :) -Toke