[Devel] [PATCH vz10] cpuacct: expose interface file in cgroup v2

[Aleksei Oladko]

In commit 0a76d99f5aa, the cpuacct controller was implicitly enabled in
cgroup v2. This patch enables user access to the cpuacct interface files
in cgroup v2, allowing statistics such as cpuacct.usage_percpu to be
retrieved in the same way as in cgroup v1.

https://virtuozzo.atlassian.net/browse/VSTOR-100092

Signed-off-by: Aleksei Oladko <aleksey.oladko at virtuozzo.com>
---
 kernel/sched/cpuacct.c | 38 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 38 insertions(+)

diff --git a/kernel/sched/cpuacct.c b/kernel/sched/cpuacct.c
index 65a331807e5d..4aa845afa9e7 100644
--- a/kernel/sched/cpuacct.c
+++ b/kernel/sched/cpuacct.c
@@ -293,6 +293,43 @@ static int cpuacct_stats_show(struct seq_file *sf, void *v)
 	return 0;
 }
 
+static struct cftype cpuacct_files[] = {
+	{
+		.name = "usage",
+		.read_u64 = cpuusage_read,
+		.write_u64 = cpuusage_write,
+	},
+	{
+		.name = "usage_user",
+		.read_u64 = cpuusage_user_read,
+	},
+	{
+		.name = "usage_sys",
+		.read_u64 = cpuusage_sys_read,
+	},
+	{
+		.name = "usage_percpu",
+		.seq_show = cpuacct_percpu_seq_show,
+	},
+	{
+		.name = "usage_percpu_user",
+		.seq_show = cpuacct_percpu_user_seq_show,
+	},
+	{
+		.name = "usage_percpu_sys",
+		.seq_show = cpuacct_percpu_sys_seq_show,
+	},
+	{
+		.name = "usage_all",
+		.seq_show = cpuacct_all_seq_show,
+	},
+	{
+		.name = "stat",
+		.seq_show = cpuacct_stats_show,
+	},
+	{ }	/* terminate */
+};
+
 static struct cftype files[] = {
 	{
 		.name = "usage",
@@ -363,6 +400,7 @@ struct cgroup_subsys cpuacct_cgrp_subsys = {
 	.css_alloc	= cpuacct_css_alloc,
 	.css_free	= cpuacct_css_free,
 	.legacy_cftypes	= files,
+	.dfl_cftypes	= cpuacct_files,
 	.early_init	= true,
 
 	.implicit_on_dfl = true,
-- 
2.43.0