Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S268805AbUJTRdw (ORCPT ); Wed, 20 Oct 2004 13:33:52 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S268779AbUJTRdu (ORCPT ); Wed, 20 Oct 2004 13:33:50 -0400 Received: from mail-relay-1.tiscali.it ([213.205.33.41]:22208 "EHLO mail-relay-1.tiscali.it") by vger.kernel.org with ESMTP id S268836AbUJTRdj (ORCPT ); Wed, 20 Oct 2004 13:33:39 -0400 Date: Wed, 20 Oct 2004 19:34:27 +0200 From: Andrea Arcangeli To: Lee Revell Cc: Arjan van de Ven , Timothy Miller , Hugh Dickins , "Martin J. Bligh" , Andrea Arcangeli , Alan Cox , Chris Wedgwood , LKML , Christoph Hellwig Subject: Re: [PATCH 1/3] Separate IRQ-stacks from 4K-stacks option Message-ID: <20041020173427.GC24619@dualathlon.random> References: <20040910151538.GA24434@devserv.devel.redhat.com> <20040910152852.GC15643@x30.random> <20040910153421.GD24434@devserv.devel.redhat.com> <41768858.8070709@techsource.com> <20041020153521.GB21556@devserv.devel.redhat.com> <1098290345.1429.65.camel@krustophenia.net> <20041020165050.GA24619@dualathlon.random> <1098291315.1429.79.camel@krustophenia.net> <20041020170802.GB24619@dualathlon.random> <1098292516.1429.116.camel@krustophenia.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1098292516.1429.116.camel@krustophenia.net> X-GPG-Key: 1024D/68B9CB43 13D9 8355 295F 4823 7C49 C012 DFA1 686E 68B9 CB43 X-PGP-Key: 1024R/CB4660B9 CC A0 71 81 F4 A0 63 AC C0 4B 81 1D 8C 15 C8 E5 User-Agent: Mutt/1.5.6i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1175 Lines: 20 On Wed, Oct 20, 2004 at 01:15:16PM -0400, Lee Revell wrote: > I was thinking of X, not audio. This might be a problem for AV sure I got it, maybe I wasn't clear but I wasn't in disagrement with you, I've never said IDE is right taking 3msec, I just taken the example you made, to add some more comment from a different point of view. Right now IDE takes 3 msec, we can turn it down to 1msec (or better move it to bh handler) but still nesting can be beneficial. It's up to the lowlevel driver to re-enable irqs if it's doing something that takes a long time. If we want to do something global that would be a nesting-max-limit (which is a sort of requirement with 4k stack IMHO), not a no-nesting, since no-nesting can be already enforced by every single irq handler, and clearly many are re-enabling irqs like IDE since they take a long time. Every time an irq handlers re-enable irqs means it's _asking_ for nesting to happen. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/