From mboxrd@z Thu Jan 1 00:00:00 1970 From: Glauber Costa Subject: Re: [PATCH 09/10] cgroup: introduce struct cfent Date: Tue, 20 Mar 2012 20:51:28 +0400 Message-ID: <4F68B590.7090204@parallels.com> References: <1331940963-15756-1-git-send-email-tj@kernel.org> <1331940963-15756-10-git-send-email-tj@kernel.org> <4F688EA9.8050905@parallels.com> <20120320160228.GD5684@google.com> <4F68AA37.80604@parallels.com> <20120320164915.GF5684@google.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20120320164915.GF5684-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Content-Type: text/plain; charset="us-ascii"; format="flowed" To: Tejun Heo Cc: ctalbott-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org, rni-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org, fweisbec-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org On 03/20/2012 08:49 PM, Tejun Heo wrote: > On Tue, Mar 20, 2012 at 08:03:03PM +0400, Glauber Costa wrote: >> From 04604201411ab0a14fa1447072cd1b273d0774ed Mon Sep 17 00:00:00 2001 >> From: Glauber Costa >> Date: Tue, 20 Mar 2012 18:12:55 +0400 >> Subject: [PATCH] don't trigger warning when d_subdirs is not empty. >> >> It is never empty at this point, because of the self references. >> a better test is to see if any of them gets d_inode set. >> >> Signed-off-by: Glauber Costa >> Signed-off-by: Tejun Heo >> --- >> kernel/cgroup.c | 8 +++++++- >> 1 files changed, 7 insertions(+), 1 deletions(-) >> >> diff --git a/kernel/cgroup.c b/kernel/cgroup.c >> index cf7b298..b45a653 100644 >> --- a/kernel/cgroup.c >> +++ b/kernel/cgroup.c >> @@ -947,10 +947,16 @@ static int cgroup_rm_file(struct cgroup *cgrp, const struct cftype *cft) >> static void cgroup_clear_directory(struct dentry *dir) >> { >> struct cgroup *cgrp = __d_cgrp(dir); >> + struct list_head *child; >> >> while (!list_empty(&cgrp->files)) >> cgroup_rm_file(cgrp, NULL); >> - WARN_ON_ONCE(!list_empty(&dir->d_subdirs)); >> + >> + list_for_each(child,&dir->d_subdirs) { >> + struct dentry *d; >> + d = list_entry(child, struct dentry, d_u.d_child); >> + WARN_ON_ONCE(d->d_inode); >> + } > > This seems correct and I'll apply this but I still can't reproduce the > warning at will before the patch. How do I a get negative dentry on > the d_subdirs when d_delete always returns 1? Glauber, can you > trigger the warning at will? > > Thanks. Yes, everytime I reboot the machine. From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757982Ab2CTQxD (ORCPT ); Tue, 20 Mar 2012 12:53:03 -0400 Received: from mx2.parallels.com ([64.131.90.16]:55416 "EHLO mx2.parallels.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757146Ab2CTQxB (ORCPT ); Tue, 20 Mar 2012 12:53:01 -0400 Message-ID: <4F68B590.7090204@parallels.com> Date: Tue, 20 Mar 2012 20:51:28 +0400 From: Glauber Costa User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:10.0.1) Gecko/20120216 Thunderbird/10.0.1 MIME-Version: 1.0 To: Tejun Heo CC: , , , , , , Subject: Re: [PATCH 09/10] cgroup: introduce struct cfent References: <1331940963-15756-1-git-send-email-tj@kernel.org> <1331940963-15756-10-git-send-email-tj@kernel.org> <4F688EA9.8050905@parallels.com> <20120320160228.GD5684@google.com> <4F68AA37.80604@parallels.com> <20120320164915.GF5684@google.com> In-Reply-To: <20120320164915.GF5684@google.com> Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [188.255.67.70] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/20/2012 08:49 PM, Tejun Heo wrote: > On Tue, Mar 20, 2012 at 08:03:03PM +0400, Glauber Costa wrote: >> From 04604201411ab0a14fa1447072cd1b273d0774ed Mon Sep 17 00:00:00 2001 >> From: Glauber Costa >> Date: Tue, 20 Mar 2012 18:12:55 +0400 >> Subject: [PATCH] don't trigger warning when d_subdirs is not empty. >> >> It is never empty at this point, because of the self references. >> a better test is to see if any of them gets d_inode set. >> >> Signed-off-by: Glauber Costa >> Signed-off-by: Tejun Heo >> --- >> kernel/cgroup.c | 8 +++++++- >> 1 files changed, 7 insertions(+), 1 deletions(-) >> >> diff --git a/kernel/cgroup.c b/kernel/cgroup.c >> index cf7b298..b45a653 100644 >> --- a/kernel/cgroup.c >> +++ b/kernel/cgroup.c >> @@ -947,10 +947,16 @@ static int cgroup_rm_file(struct cgroup *cgrp, const struct cftype *cft) >> static void cgroup_clear_directory(struct dentry *dir) >> { >> struct cgroup *cgrp = __d_cgrp(dir); >> + struct list_head *child; >> >> while (!list_empty(&cgrp->files)) >> cgroup_rm_file(cgrp, NULL); >> - WARN_ON_ONCE(!list_empty(&dir->d_subdirs)); >> + >> + list_for_each(child,&dir->d_subdirs) { >> + struct dentry *d; >> + d = list_entry(child, struct dentry, d_u.d_child); >> + WARN_ON_ONCE(d->d_inode); >> + } > > This seems correct and I'll apply this but I still can't reproduce the > warning at will before the patch. How do I a get negative dentry on > the d_subdirs when d_delete always returns 1? Glauber, can you > trigger the warning at will? > > Thanks. Yes, everytime I reboot the machine.