--- old/src/java.base/linux/classes/jdk/internal/platform/cgroupv1/CgroupV1Subsystem.java	2020-01-09 20:39:14.707140901 +0100
+++ new/src/java.base/linux/classes/jdk/internal/platform/cgroupv1/CgroupV1Subsystem.java	2020-01-09 20:39:14.571140759 +0100
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018, 2019, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2018, 2020, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -33,6 +33,7 @@
 import jdk.internal.platform.CgroupSubsystem;
 import jdk.internal.platform.CgroupSubsystemController;
 import jdk.internal.platform.CgroupUtil;
+import jdk.internal.platform.Metrics;
 
 public class CgroupV1Subsystem implements CgroupSubsystem {
     private CgroupV1MemorySubSystemController memory;
@@ -283,7 +284,7 @@
     public long[] getPerCpuUsage() {
         String usagelist = CgroupSubsystemController.getStringValue(cpuacct, "cpuacct.usage_percpu");
         if (usagelist == null) {
-            return new long[0];
+            return null;
         }
 
         String list[] = usagelist.split(" ");
@@ -319,7 +320,7 @@
     public long getCpuShares() {
         long retval = getLongValue(cpu, "cpu.shares");
         if (retval == 0 || retval == 1024)
-            return -1;
+            return Metrics.LONG_RETVAL_UNLIMITED;
         else
             return retval;
     }
@@ -365,7 +366,7 @@
         return CgroupSubsystemController.getDoubleValue(cpuset, "cpuset.memory_pressure");
     }
 
-    public boolean isCpuSetMemoryPressureEnabled() {
+    public Boolean isCpuSetMemoryPressureEnabled() {
         long val = getLongValue(cpuset, "cpuset.memory_pressure_enabled");
         return (val == 1);
     }
@@ -473,7 +474,7 @@
         return getLongValue(memory, "memory.memsw.usage_in_bytes");
     }
 
-    public boolean isMemoryOOMKillEnabled() {
+    public Boolean isMemoryOOMKillEnabled() {
         long val = CgroupSubsystemController.getLongEntry(memory, "memory.oom_control", "oom_kill_disable");
         return (val == 0);
     }