Return-path: Received: from smtp.codeaurora.org ([198.145.29.96]:59242 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726628AbeHVAro (ORCPT ); Tue, 21 Aug 2018 20:47:44 -0400 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Date: Tue, 21 Aug 2018 14:25:54 -0700 From: Rajkumar Manoharan To: =?UTF-8?Q?Toke_H=C3=B8iland-J=C3=B8rgensen?= Cc: johannes@sipsolutions.net, linux-wireless@vger.kernel.org Subject: Re: [RFC 3/3] mac80211: add ieee80211_reorder_txq In-Reply-To: <87a7pfaovy.fsf@toke.dk> References: <1534202011-13101-1-git-send-email-rmanohar@codeaurora.org> <1534202011-13101-4-git-send-email-rmanohar@codeaurora.org> <87a7pfaovy.fsf@toke.dk> Message-ID: (sfid-20180821_232558_466351_95210704) Sender: linux-wireless-owner@vger.kernel.org List-ID: On 2018-08-21 05:24, Toke Høiland-Jørgensen wrote: > Rajkumar Manoharan writes: > >> This allows the driver to refill airtime fairness deficit >> where the driver will not access txqs by ieee80211_next_txq. >> In tx push mode data path, high priority txqs will be scheduled >> for data transmission by ieee80211_next_txq and driver will not >> prioritize txqs whereas in push-pull mode, the drivers can >> prioritize txqs and access them directly. In such mode, airtime >> deficit can not filled by ieee80211_next_txq. >> [...] > > This needs to check that the txq is currently at the head of > local->active_txqs[txqi->txq.ac]; otherwise fairness enforcement > doesn't > work. And with this check I'm not sure the reorder function is terribly > useful for what you want to use it for? > Hmm.. I tried to keep the same policy of next_txq(). i.e do not allow serving txqs when the deficit is negative. reorder_txq() limits over serving the same txq by driver. So that driver is given chance to serve other txqs. As mentioned earlier, next_txq() can not be used for fetching txq directly. So reorder_txq() needs to take care of refilling txq after serving them. -Rajkumar