From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Thu, 19 Apr 2001 08:33:42 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Thu, 19 Apr 2001 08:33:33 -0400 Received: from oboe.it.uc3m.es ([163.117.139.101]:5647 "EHLO oboe.it.uc3m.es") by vger.kernel.org with ESMTP id ; Thu, 19 Apr 2001 08:33:21 -0400 From: "Peter T. Breuer" Message-Id: <200104191233.f3JCX8s22171@oboe.it.uc3m.es> Subject: Re: block devices don't work without plugging in 2.4.3 In-Reply-To: <20010419135417.Q16822@suse.de> from "Jens Axboe" at "Apr 19, 2001 01:54:17 pm" To: "Jens Axboe" Date: Thu, 19 Apr 2001 14:33:08 +0200 (MET DST) CC: "linux kernel" X-Anonymously-To: Reply-To: ptb@it.uc3m.es X-Mailer: ELM [version 2.4ME+ PL66 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org "A month of sundays ago Jens Axboe wrote:" > On Thu, Apr 19 2001, Peter T. Breuer wrote: > > So the consensus is that I should enable plugging while the plugging > > function is still here and do nothing when it goes? I must say I don't > > think it should really "go", since that means I have to add a no-op > > macro to replace it, and I don't like #ifdefs. > > The moral would be that you should never do anything. You didn't enable > plugging with blk_queue_pluggable, only disabled it by using a noop > plug. I was thinking about what has to be done to allow my code to compile in older kernels. I _believe_ (I may be mistaken) that I had to _explicitly_ disable plugging at some stage. Probably in 2.2. and possibly in 2.4.0. On that basis, I do need a plug_fn and a blk_queue_pluggable for compilation against those kernels, and these should both be macro'ed to oblivion in the newest kernels. No? Apologies for the continued vagueness. There are a lot of states to consider: two machine states (plugged/not plugged) and several code states (whatever had to be done when to cause what). Peter