cgroup: hold cgroup_mutex before calling css_offline()
cpuset no longer nests cgroup_mutex inside cpu_hotplug lock, so
we don't have to release cgroup_mutex before calling css_offline().
Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
diff --git a/Documentation/cgroups/cgroups.txt b/Documentation/cgroups/cgroups.txt
index bcf1a00..0028e88 100644
--- a/Documentation/cgroups/cgroups.txt
+++ b/Documentation/cgroups/cgroups.txt
@@ -580,6 +580,7 @@
cgroup_for_each_descendant_pre() for details.
void css_offline(struct cgroup *cgrp);
+(cgroup_mutex held by caller)
This is the counterpart of css_online() and called iff css_online()
has succeeded on @cgrp. This signifies the beginning of the end of