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| author | Tejun Heo <tj@kernel.org> | 2014-05-14 09:15:01 -0400 |
|---|---|---|
| committer | Tejun Heo <tj@kernel.org> | 2014-05-14 09:15:01 -0400 |
| commit | cbc125efada6d8c2555dd35e938694eb9b7cd791 (patch) | |
| tree | 97f8581666b3b79d541955c9c50d1268bd1883a7 /kernel/cgroup.c | |
| parent | 9d800df12d31734a6853915e9d2deb5d6747985f (diff) | |
| download | lwn-cbc125efada6d8c2555dd35e938694eb9b7cd791.tar.gz lwn-cbc125efada6d8c2555dd35e938694eb9b7cd791.zip | |
cgroup: separate out cgroup_has_live_children() from cgroup_destroy_locked()
We're expecting another user.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Diffstat (limited to 'kernel/cgroup.c')
| -rw-r--r-- | kernel/cgroup.c | 26 |
1 files changed, 16 insertions, 10 deletions
diff --git a/kernel/cgroup.c b/kernel/cgroup.c index b57a949ae4bc..3f5f48130b6b 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -3295,6 +3295,21 @@ css_next_descendant_post(struct cgroup_subsys_state *pos, return css_parent(pos); } +static bool cgroup_has_live_children(struct cgroup *cgrp) +{ + struct cgroup *child; + + rcu_read_lock(); + list_for_each_entry_rcu(child, &cgrp->children, sibling) { + if (!cgroup_is_dead(child)) { + rcu_read_unlock(); + return true; + } + } + rcu_read_unlock(); + return false; +} + /** * css_advance_task_iter - advance a task itererator to the next css_set * @it: the iterator to advance @@ -4465,7 +4480,6 @@ static void kill_css(struct cgroup_subsys_state *css) static int cgroup_destroy_locked(struct cgroup *cgrp) __releases(&cgroup_mutex) __acquires(&cgroup_mutex) { - struct cgroup *child; struct cgroup_subsys_state *css; bool empty; int ssid; @@ -4487,15 +4501,7 @@ static int cgroup_destroy_locked(struct cgroup *cgrp) * emptiness as dead children linger on it while being destroyed; * otherwise, "rmdir parent/child parent" may fail with -EBUSY. */ - empty = true; - rcu_read_lock(); - list_for_each_entry_rcu(child, &cgrp->children, sibling) { - empty = cgroup_is_dead(child); - if (!empty) - break; - } - rcu_read_unlock(); - if (!empty) + if (cgroup_has_live_children(cgrp)) return -EBUSY; /* |