From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from wr-out-0506.google.com ([64.233.184.231]:59704 "EHLO wr-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752194AbYGIO7Q (ORCPT ); Wed, 9 Jul 2008 10:59:16 -0400 Received: by wr-out-0506.google.com with SMTP id 69so2164852wri.5 for ; Wed, 09 Jul 2008 07:59:15 -0700 (PDT) To: Johannes Berg Subject: Re: [PATCH 1/3] mac80211: Include sequence number in IBSS and Mesh beacons Date: Wed, 9 Jul 2008 17:08:04 +0200 Cc: Michael Buesch , "John W. Linville" , linux-wireless@vger.kernel.org, rt2400-devel@lists.sourceforge.net References: <200807091511.14288.IvDoorn@gmail.com> <200807091637.02090.IvDoorn@gmail.com> <1215614895.3246.17.camel@johannes.berg> In-Reply-To: <1215614895.3246.17.camel@johannes.berg> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-15" Message-Id: <200807091708.04870.IvDoorn@gmail.com> (sfid-20080709_165919_690389_57EF815B) From: Ivo van Doorn Sender: linux-wireless-owner@vger.kernel.org List-ID: On Wednesday 09 July 2008, Johannes Berg wrote: > > > If rt2x00 would use a global lock to block all TX and beacons, then yes. > > But rt2x00 uses per-queue locking. When a beacon is being updated rt2x00 > > will still allow regular frames to be queued. > > That just widens the window. And if you have multiple queues then you > can't do sw sequence numbers anyway because the hardware might reorder > the frames. That doesn't seem to be a problem in the legacy drivers, so I guess the hardware does *something* to prevent problems. > > As far as rt2x00 is concerned, all hardware that supports multi-bss also > > support HW sequence counters. rt2400pci and rt2500pci are the only ones > > requiring SW sequence counters, and they can't do multi-bss. > > Do they keep per-BSS counters? Not sure what you mean, but rt2400pci and rt2500pci don't support multi-bss, so they wouldn't have per-BSS counters. rt61pci and rt73usb do support multi-bss and keep the sequence counting completely in firmware/hardware and I am not sure how they can be read by the driver. So I don't know how those are stored either. Ivo