From 221e85f6f2e11455cdeeb5b2d4cfd93b51b575c1 Mon Sep 17 00:00:00 2001
From: Nicholas Orlowsky <nickorlow@nickorlow.com>
Date: Fri, 31 Mar 2023 00:36:12 -0500
Subject: [PATCH] added version detecting

---
 pkg/util/runtime/cpu_linux.go | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/pkg/util/runtime/cpu_linux.go b/pkg/util/runtime/cpu_linux.go
index a69a4432c..431691a7e 100644
--- a/pkg/util/runtime/cpu_linux.go
+++ b/pkg/util/runtime/cpu_linux.go
@@ -62,8 +62,12 @@ func NumCPU() int {
 }
 
 func getCgroupVersion() int64 {
-	// TODO: detect version
-	return 2;
+	// /sys/fs/cgroup/cgroup.controllers will not exist with cgroupsv1
+	if _, err := os.Stat("/sys/fs/cgroup/cgroup.controllers"); err == nil {
+		return 2;
+	} else {
+		return 1;
+	}
 }
 
 func readCgroup2FileToInt64Tuple(cgroupPath, cgroupFile string) (int64, int64) {
@@ -75,6 +79,7 @@ func readCgroup2FileToInt64Tuple(cgroupPath, cgroupFile string) (int64, int64) {
 
 	// file contents looks like: $MAX $PERIOD
 	// $MAX can have value "max" indicating no limit
+	// it is possible for $PERIOD to be unset
 
 	values :=  strings.Fields(string(contents));