[PATCH -next] cgroup: distinguish name and legacy_name when show /proc/cgroups

[Chen Ridong]

Subsys_name may be different between v1 and v2. In cgroup v2
blk subsys_name is io, while it is named blkio in cgroup v1.
It better to distinguish name and legacy_name when we cat /proc/cgroups.

Signed-off-by: Chen Ridong <chenridong@xxxxxxxxxx>
---
 kernel/cgroup/cgroup-v1.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/kernel/cgroup/cgroup-v1.c b/kernel/cgroup/cgroup-v1.c
index b9dbf6bf2779..b29252ad91b6 100644
--- a/kernel/cgroup/cgroup-v1.c
+++ b/kernel/cgroup/cgroup-v1.c
@@ -677,7 +677,8 @@ int proc_cgroupstats_show(struct seq_file *m, void *v)
 
 	for_each_subsys(ss, i)
 		seq_printf(m, "%s\t%d\t%d\t%d\n",
-			   ss->legacy_name, ss->root->hierarchy_id,
+			   ss->root == &cgrp_dfl_root ? ss->name : ss->legacy_name,
+			   ss->root->hierarchy_id,
 			   atomic_read(&ss->root->nr_cgrps),
 			   cgroup_ssid_enabled(i));
 
-- 
2.34.1