From mboxrd@z Thu Jan 1 00:00:00 1970 From: Li Zefan Subject: Re: [PATCH 5/8] cgroup: remove CGRP_WAIT_ON_RMDIR, cgroup_exclude_rmdir() and cgroup_release_and_wakeup_rmdir() Date: Mon, 5 Nov 2012 13:40:05 +0800 Message-ID: <50975135.5070600@huawei.com> References: <1351712650-23709-1-git-send-email-tj@kernel.org> <1351712650-23709-6-git-send-email-tj@kernel.org> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1351712650-23709-6-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: hannes-druUgvl0LCNAfugRpC6u6w@public.gmane.org, mhocko-AlSwsSmVLrQ@public.gmane.org, bsingharora-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, kamezawa.hiroyu-+CUm20s59erQFUHtdCDX3A@public.gmane.org, containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org On 2012/11/1 3:44, Tejun Heo wrote: > CGRP_WAIT_ON_RMDIR is another kludge which was added to make cgroup > destruction rollback somewhat working. cgroup_rmdir() used to drain > CSS references and CGRP_WAIT_ON_RMDIR and the associated waitqueue and > helpers were used to allow the task performing rmdir to wait for the > next relevant event. > > Unfortunately, the wait is visible to controllers too and the > mechanism got exposed to memcg by 887032670d ("cgroup avoid permanent > sleep at rmdir"). > > Now that the draining and retries are gone, CGRP_WAIT_ON_RMDIR is > unnecessary. Remove it and all the mechanisms supporting it. Note > that memcontrol.c changes are essentially revert of 887032670d > ("cgroup avoid permanent sleep at rmdir"). > > Signed-off-by: Tejun Heo > Reviewed-by: Michal Hocko > Cc: Balbir Singh > Cc: KAMEZAWA Hiroyuki > --- > include/linux/cgroup.h | 21 --------------------- > kernel/cgroup.c | 51 -------------------------------------------------- > mm/memcontrol.c | 24 +----------------------- > 3 files changed, 1 insertion(+), 95 deletions(-) Acked-by: Li Zefan