From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kamezawa Hiroyuki Subject: Re: [PATCH 8/9] cgroup_freezer: add ->post_create() and ->pre_destroy() and track online state Date: Thu, 08 Nov 2012 13:48:25 +0900 Message-ID: <509B3999.6060505@jp.fujitsu.com> References: <1351931915-1701-1-git-send-email-tj@kernel.org> <1351931915-1701-9-git-send-email-tj@kernel.org> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1351931915-1701-9-git-send-email-tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org> Sender: cgroups-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: Content-Type: text/plain; charset="us-ascii" To: Tejun Heo Cc: lizefan-hv44wF8Li93QT0dZR+AlfA@public.gmane.org, mhocko-AlSwsSmVLrQ@public.gmane.org, rjw-KKrjLPT3xs0@public.gmane.org, containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-pm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, fweisbec-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org (2012/11/03 17:38), Tejun Heo wrote: > A cgroup is online and visible to iteration between ->post_create() > and ->pre_destroy(). This patch introduces CGROUP_FREEZER_ONLINE and > toggles it from the newly added freezer_post_create() and > freezer_pre_destroy() while holding freezer->lock such that a > cgroup_freezer can be reilably distinguished to be online. This will > be used by full hierarchy support. > > ONLINE test is added to freezer_apply_state() but it currently doesn't > make any difference as freezer_write() can only be called for an > online cgroup. > > Adjusting system_freezing_cnt on destruction is moved from > freezer_destroy() to the new freezer_pre_destroy() for consistency. > > This patch doesn't introduce any noticeable behavior change. > > Signed-off-by: Tejun Heo > --- > kernel/cgroup_freezer.c | 42 ++++++++++++++++++++++++++++++++++++++++-- > 1 file changed, 40 insertions(+), 2 deletions(-) > > diff --git a/kernel/cgroup_freezer.c b/kernel/cgroup_freezer.c > index b8ad93c..4f12d31 100644 > --- a/kernel/cgroup_freezer.c > +++ b/kernel/cgroup_freezer.c > @@ -23,6 +23,7 @@ > #include > > enum freezer_state_flags { > + CGROUP_FREEZER_ONLINE = (1 << 0), /* freezer is fully online */ Could you explain what 'online' means here again, rather than changelog ? BTW, 'online' is a shared concept, between post_create() and pre_destroy(), among developpers ? Is it new ? Anyway, the patch itself is simple. Reviewed-by: KAMEZAWA Hiroyuki