Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757918AbZDPQH2 (ORCPT ); Thu, 16 Apr 2009 12:07:28 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753946AbZDPQHO (ORCPT ); Thu, 16 Apr 2009 12:07:14 -0400 Received: from mx3.mail.elte.hu ([157.181.1.138]:40661 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754888AbZDPQHN (ORCPT ); Thu, 16 Apr 2009 12:07:13 -0400 Date: Thu, 16 Apr 2009 18:06:45 +0200 From: Ingo Molnar To: Alessio Igor Bogani , Alexander Viro Cc: Frederic Weisbecker , Peter Zijlstra , LKML , Jonathan Corbet Subject: Re: [PATCH -tip] remove the BKL: Replace BKL in mount/umount syscalls with a mutex Message-ID: <20090416160645.GB17804@elte.hu> References: <1239892078-6039-1-git-send-email-abogani@texware.it> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1239892078-6039-1-git-send-email-abogani@texware.it> User-Agent: Mutt/1.5.18 (2008-05-17) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.3 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1624 Lines: 41 * Alessio Igor Bogani wrote: > Replace ths BKL in sys_mount()/sys_umount() syscalls with a regular mutex. > > Signed-off-by: Alessio Igor Bogani > --- > fs/namespace.c | 16 +++++++++------- > fs/super.c | 9 ++++----- > 2 files changed, 13 insertions(+), 12 deletions(-) Ok, this patch needs to be flamed^W commented on by Al. Al: this patch is very likely broken as i cannot imagine you leaving the BKL there just so. So lets accept that (and your NAK) as a given and not get upset about it too much. We are willing to fix any side effects and preconditions before this can be done - and it would be nice if you could donate a few minutes to this effort by enumerating those preconditions for us, so that we can provide the real fixes. No-one knows this code better than you so even if we could guess our way around to a certain degree, some maintainer guidance and insight would be deeply appreciated. I'm wondering how much the BKL use here is made necessary by the sys_open() BKL use in device drivers. Jonathan has done extensive work on the sys_open front (and there's more such work in tip:core/kill-the-BKL) - perhaps that has largely paved the way for this change? There's also ioctl BKL use - is the BKL use here in sys_mount necessiated by the (naked) BKL use in those handlers? Thanks, Ingo -- 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/