[PATCH] cgroup: short-circuit current_cgns_cgroup_from_root() on the default hierarchy

[Miaohe Lin]

Like commit 13d82fb77abb ("cgroup: short-circuit cset_cgroup_from_root() on
the default hierarchy"), short-circuit current_cgns_cgroup_from_root() on
the default hierarchy.

Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
---
 kernel/cgroup/cgroup.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c
index 8be1da1ebd9a..b90c8b200aa2 100644
--- a/kernel/cgroup/cgroup.c
+++ b/kernel/cgroup/cgroup.c
@@ -1374,6 +1374,8 @@ current_cgns_cgroup_from_root(struct cgroup_root *root)
 	cset = current->nsproxy->cgroup_ns->root_cset;
 	if (cset == &init_css_set) {
 		res = &root->cgrp;
+	} else if (root == &cgrp_dfl_root) {
+		res = cset->dfl_cgrp;
 	} else {
 		struct cgrp_cset_link *link;
 
-- 
2.21.GIT