Return-path: Received: from nbd.name ([46.4.11.11]:37249 "EHLO nbd.name" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758137Ab3BGOD0 (ORCPT ); Thu, 7 Feb 2013 09:03:26 -0500 Message-ID: <5113B42A.4020708@openwrt.org> (sfid-20130207_150329_604633_029233B3) Date: Thu, 07 Feb 2013 15:03:22 +0100 From: Felix Fietkau MIME-Version: 1.0 To: Krishna Chaitanya CC: Johannes Berg , chaitanyatk@posedge.com, linux-wireless@vger.kernel.org, maheshp@posedge.com Subject: Re: [RFC] mac80211: Add support for Tx-AMSDU viz debugfs. References: <7384f4ddc838247a0f467708d66baa8c@posedge.com> <1360225230.8038.1.camel@jlt4.sipsolutions.net> <1360228991.8038.3.camel@jlt4.sipsolutions.net> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-wireless-owner@vger.kernel.org List-ID: On 2013-02-07 10:30 AM, Krishna Chaitanya wrote: > On Thu, Feb 7, 2013 at 2:53 PM, Johannes Berg wrote: >> On Thu, 2013-02-07 at 14:49 +0530, Krishna Chaitanya wrote: >>> On Thu, Feb 7, 2013 at 1:50 PM, Johannes Berg wrote: >>> > On Thu, 2013-02-07 at 00:01 -0800, chaitanyatk@posedge.com wrote: >>> > >>> >>> > Hmm. I'm not exactly happy with using (one of) the last control flag for >>> > a pure debug facility. >>> > >>> Hmm...initially i tried to add qos header in the debugfs itself but to avoid >>> code redundancy went with the TX_CTL. But in either case we need some kind >>> of flag to skip adding the qos header by mac80211 (or) to set the AMSDU >>> bit in the qos control header. >> >> I guess the question is whether we really need this code in the tree at >> all? It seems like a (relatively) obscure debug feature for which I'm >> not sure we should touch the TX fastpath? > > AMSDU in itself is rarely used feature in 802.11. So your concern i s > understandable. > > But the problem is every time we have to test the Rx-AMSDU > which is mandatory for WFA 802.11n cert, we need to procure a adapter > which supports it, which is difficult. Thats the scenario we have faced > which lead us to work on this.With this feature in place we can use > any opensource adapter and driver for that purpose. > > Again, Its a trade off between stability and usability :-) How about injecting A-MSDU packets via cooked monitor mode or nl80211 frame tx and thus shifting the debug-only code into userspace? - Felix