From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arjan van de Ven Date: Tue, 20 May 2008 16:58:55 -0000 Subject: [Ocfs2-devel] [RFC][PATCH 0/3] configfs: Make nested default groups lockdep-friendly In-Reply-To: <20080520163320.025971210@kerlabs.com> References: <20080520163320.025971210@kerlabs.com> Message-ID: <20080520095810.1d50d247@infradead.org> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Louis Rilling Cc: Joel.Becker@oracle.com, linux-kernel@vger.kernel.org, ocfs2-devel@oss.oracle.com On Tue, 20 May 2008 18:33:20 +0200 Louis Rilling wrote: > Hi all, > > The following patches fix lockdep warnings resulting from (correct) > recursive locking in configfs. > > Current lockdep annotations for inode mutexes in configfs are > lockdep-friendly provided that: > 1/ config_groups have at most one level of default groups (see > configfs_attach_group()), > 2/ config_groups having default groups are never removed (see > configfs_detach_prep()). > > Since lockdep does not handle such correct recursion, the idea is to > insert lockdep_off()/lockdep_on() for inode mutexes as soon as the > level of recursion of the I_MUTEX_PARENT -> I_MUTEX_CHILD dependency > pattern increases. I'm... not entirely happy with such a solution ;( there must be a better one. From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933094AbYETQ6i (ORCPT ); Tue, 20 May 2008 12:58:38 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756678AbYETQ61 (ORCPT ); Tue, 20 May 2008 12:58:27 -0400 Received: from pentafluge.infradead.org ([213.146.154.40]:51675 "EHLO pentafluge.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751309AbYETQ60 (ORCPT ); Tue, 20 May 2008 12:58:26 -0400 Date: Tue, 20 May 2008 09:58:10 -0700 From: Arjan van de Ven To: Louis Rilling Cc: Joel.Becker@oracle.com, Louis.Rilling@kerlabs.com, linux-kernel@vger.kernel.org, ocfs2-devel@oss.oracle.com Subject: Re: [RFC][PATCH 0/3] configfs: Make nested default groups lockdep-friendly Message-ID: <20080520095810.1d50d247@infradead.org> In-Reply-To: <20080520163320.025971210@kerlabs.com> References: <20080520163320.025971210@kerlabs.com> Organization: Intel X-Mailer: Claws Mail 3.3.1 (GTK+ 2.12.9; i386-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-SRS-Rewrite: SMTP reverse-path rewritten from by pentafluge.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 20 May 2008 18:33:20 +0200 Louis Rilling wrote: > Hi all, > > The following patches fix lockdep warnings resulting from (correct) > recursive locking in configfs. > > Current lockdep annotations for inode mutexes in configfs are > lockdep-friendly provided that: > 1/ config_groups have at most one level of default groups (see > configfs_attach_group()), > 2/ config_groups having default groups are never removed (see > configfs_detach_prep()). > > Since lockdep does not handle such correct recursion, the idea is to > insert lockdep_off()/lockdep_on() for inode mutexes as soon as the > level of recursion of the I_MUTEX_PARENT -> I_MUTEX_CHILD dependency > pattern increases. I'm... not entirely happy with such a solution ;( there must be a better one.