diff --git a/src/basic/cgroup-util.h b/src/basic/cgroup-util.h
index 9b410f1f58..463a8dc84a 100644
--- a/src/basic/cgroup-util.h
+++ b/src/basic/cgroup-util.h
@@ -60,6 +60,15 @@ typedef enum CGroupMask {
         _CGROUP_MASK_ALL = CGROUP_CONTROLLER_TO_MASK(_CGROUP_CONTROLLER_MAX) - 1
 } CGroupMask;
 
+static inline CGroupMask CGROUP_MASK_EXTEND_JOINED(CGroupMask mask) {
+        /* We always mount "cpu" and "cpuacct" in the same hierarchy. Hence, when one bit is set also set the other */
+
+        if (mask & (CGROUP_MASK_CPU|CGROUP_MASK_CPUACCT))
+                mask |= (CGROUP_MASK_CPU|CGROUP_MASK_CPUACCT);
+
+        return mask;
+}
+
 /* Special values for all weight knobs on unified hierarchy */
 #define CGROUP_WEIGHT_INVALID ((uint64_t) -1)
 #define CGROUP_WEIGHT_MIN UINT64_C(1)