cgroup: relocate setting of CGRP_DEAD

In cgroup_destroy_locked(), move setting of CGRP_DEAD above
invocations of kill_css().  This doesn't make any visible behavior
difference now but will be used to inhibit manipulating controller
enable states of a dying cgroup on the unified hierarchy.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
This commit is contained in:
Tejun Heo 2014-03-19 10:23:53 -04:00
parent b8dadcb58d
commit 5d77381fd8

View file

@ -3867,6 +3867,15 @@ static int cgroup_destroy_locked(struct cgroup *cgrp)
if (!empty)
return -EBUSY;
/*
* Mark @cgrp dead. This prevents further task migration and child
* creation by disabling cgroup_lock_live_group(). Note that
* CGRP_DEAD assertion is depended upon by css_next_child() to
* resume iteration after dropping RCU read lock. See
* css_next_child() for details.
*/
set_bit(CGRP_DEAD, &cgrp->flags);
/*
* Initiate massacre of all css's. cgroup_destroy_css_killed()
* will be invoked to perform the rest of destruction once the
@ -3878,15 +3887,6 @@ static int cgroup_destroy_locked(struct cgroup *cgrp)
kill_css(css);
mutex_lock(&cgroup_mutex);
/*
* Mark @cgrp dead. This prevents further task migration and child
* creation by disabling cgroup_lock_live_group(). Note that
* CGRP_DEAD assertion is depended upon by css_next_child() to
* resume iteration after dropping RCU read lock. See
* css_next_child() for details.
*/
set_bit(CGRP_DEAD, &cgrp->flags);
/* CGRP_DEAD is set, remove from ->release_list for the last time */
raw_spin_lock(&release_list_lock);
if (!list_empty(&cgrp->release_list))