From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751171AbVJHWU6 (ORCPT ); Sat, 8 Oct 2005 18:20:58 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751170AbVJHWU6 (ORCPT ); Sat, 8 Oct 2005 18:20:58 -0400 Received: from gate.crashing.org ([63.228.1.57]:36319 "EHLO gate.crashing.org") by vger.kernel.org with ESMTP id S1751165AbVJHWU5 (ORCPT ); Sat, 8 Oct 2005 18:20:57 -0400 Subject: Re: IDE issues with "choose_drive" From: Benjamin Herrenschmidt To: Bartlomiej Zolnierkiewicz Cc: Jens Axboe , Linux Kernel list , list linux-ide In-Reply-To: <58cb370e0510080129i80710c7gc2178b9330a1ee19@mail.gmail.com> References: <1128559019.22073.19.camel@gaston> <1128560569.22073.25.camel@gaston> <1128734104.17365.73.camel@gaston> <58cb370e0510080129i80710c7gc2178b9330a1ee19@mail.gmail.com> Content-Type: text/plain Date: Sun, 09 Oct 2005 08:18:33 +1000 Message-Id: <1128809913.17365.78.camel@gaston> Mime-Version: 1.0 X-Mailer: Evolution 2.2.3 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org > It seems we need internal ide_dev_do_request(ide_drive_t *, int) > which will explicitly state which device we want to service as I see > no sane way to fix the problem in choose_drive(). Not only that, but if you read my blurb, I wonder how even the non-targetted case can work properly if we ever hit a couple of the code path in there that either early exit because the elevator returned no request or the case where we "sleep" a drive to give more time to the other... I have the feeling that we may "miss" an opportunity to servive a drive, and thus this drive will stick around with a pending request not beeing serviced... I reckon those are corner cases, but I feel the whole thing need some serious revisiting. > Your workaround is OK for 2.6.14 given that you will document it > now and later fix it properly for 2.6.15. Ok. Well, I'm not sure what is the right fix at the moment given the other issues I described above, but I'm definitely up to doign a proper fix for 2.6.15 with your help ;) Ben.