--- old/test/lib/jdk/test/lib/containers/cgroup/MetricsTesterCgroupV2.java	2020-01-09 20:39:22.272148835 +0100
+++ new/test/lib/jdk/test/lib/containers/cgroup/MetricsTesterCgroupV2.java	2020-01-09 20:39:22.131148687 +0100
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019, Red Hat Inc.
+ * Copyright (c) 2020, Red Hat Inc.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -149,10 +149,6 @@
         CgroupMetricsTester.fail(UnifiedController.NAME, metric, oldVal, newVal);
     }
 
-    private void fail(String metric, String message) {
-        throw new RuntimeException(metric + ": " + message);
-    }
-
     private void warn(String metric, long oldVal, long newVal) {
         CgroupMetricsTester.warn(UnifiedController.NAME, metric, oldVal, newVal);
     }
@@ -169,9 +165,7 @@
     }
 
     private void verifyPerCpuNotSupported(long[] perCpuUsage) {
-        if (!Arrays.equals(perCpuUsage, new long[0])) {
-            throw new RuntimeException("perCpuUsage expected to be not supported");
-        };
+        Asserts.assertNull(perCpuUsage, "perCpuUsage expected to be not supported");
     }
 
     private long getCpuShares(String file) {
@@ -212,6 +206,9 @@
 
     private long getCpuValueFromFile(String file, int index) {
         String maxPeriod = getStringVal(file);
+        if (maxPeriod == null) {
+            return UNLIMITED;
+        }
         String[] tokens = maxPeriod.split("\\s+");
         String val = tokens[index];
         if (MAX.equals(val)) {
@@ -228,7 +225,6 @@
     public void testMemorySubsystem() {
         Metrics metrics = Metrics.systemMetrics();
 
-        long memoryMaxUsageMin;
         // User Memory
         long oldVal = metrics.getMemoryFailCount();
         long newVal = getLongValueEntryFromFile("memory.events", "max");
@@ -242,20 +238,12 @@
             fail("memory.max", oldVal, newVal);
         }
 
-        memoryMaxUsageMin = oldVal = metrics.getMemoryUsage();
+        oldVal = metrics.getMemoryUsage();
         newVal = getLongValueFromFile("memory.current");
         if (!CgroupMetricsTester.compareWithErrorMargin(oldVal, newVal)) {
             fail("memory.current", oldVal, newVal);
         }
-
-        // Memory max has no knowledge of out of band read to "memory.current"
-        // above. Fix that by calling it again.
-        metrics.getMemoryUsage();
-        long memoryMax = metrics.getMemoryMaxUsage();
-        if (memoryMax < memoryMaxUsageMin || memoryMax < newVal) {
-            fail("memoryMaxUsage", "old usages [ " + memoryMaxUsageMin + ", " +
-                                   newVal + " ] >= " + memoryMax);
-        }
+        verifyNotSupported(metrics.getMemoryMaxUsage());
 
         // Kernel memory
         verifyNotSupported(metrics.getKernelMemoryFailCount());
@@ -267,7 +255,12 @@
         verifyNotSupported(metrics.getTcpMemoryFailCount());
         verifyNotSupported(metrics.getTcpMemoryLimit());
         verifyNotSupported(metrics.getTcpMemoryMaxUsage());
-        verifyNotSupported(metrics.getTcpMemoryUsage());
+
+        oldVal = metrics.getTcpMemoryUsage();
+        newVal = getLongValueEntryFromFile("memory.stat", "sock");
+        if (!CgroupMetricsTester.compareWithErrorMargin(oldVal, newVal)) {
+            fail("memory.stat[sock]", oldVal, newVal);
+        }
 
         //  Memory and Swap
         verifyNotSupported(metrics.getMemoryAndSwapFailCount());
@@ -291,7 +284,7 @@
             fail("memory.high", oldVal, newVal);
         }
 
-        Asserts.assertFalse(metrics.isMemoryOOMKillEnabled(), "Not supported");
+        Asserts.assertNull(metrics.isMemoryOOMKillEnabled(), "Not supported");
     }
 
     @Override
@@ -362,7 +355,8 @@
     @Override
     public void testCpuSets() {
         Metrics metrics = Metrics.systemMetrics();
-        Integer[] oldVal = Arrays.stream(metrics.getCpuSetCpus()).boxed().toArray(Integer[]::new);
+        int[] cpus = mapNullToEmpty(metrics.getCpuSetCpus());
+        Integer[] oldVal = Arrays.stream(cpus).boxed().toArray(Integer[]::new);
         Arrays.sort(oldVal);
 
         String cpusstr = getStringVal("cpuset.cpus");
@@ -374,7 +368,8 @@
                                 Arrays.toString(newVal));
         }
 
-        oldVal = Arrays.stream(metrics.getEffectiveCpuSetCpus()).boxed().toArray(Integer[]::new);
+        cpus = mapNullToEmpty(metrics.getEffectiveCpuSetCpus());
+        oldVal = Arrays.stream(cpus).boxed().toArray(Integer[]::new);
         Arrays.sort(oldVal);
         cpusstr = getStringVal("cpuset.cpus.effective");
         newVal = CgroupMetricsTester.convertCpuSetsToArray(cpusstr);
@@ -384,7 +379,8 @@
                                           Arrays.toString(newVal));
         }
 
-        oldVal = Arrays.stream(metrics.getCpuSetMems()).boxed().toArray(Integer[]::new);
+        cpus = mapNullToEmpty(metrics.getCpuSetMems());
+        oldVal = Arrays.stream(cpus).boxed().toArray(Integer[]::new);
         Arrays.sort(oldVal);
         cpusstr = getStringVal("cpuset.mems");
         newVal = CgroupMetricsTester.convertCpuSetsToArray(cpusstr);
@@ -394,7 +390,8 @@
                                 Arrays.toString(newVal));
         }
 
-        oldVal = Arrays.stream(metrics.getEffectiveCpuSetMems()).boxed().toArray(Integer[]::new);
+        cpus = mapNullToEmpty(metrics.getEffectiveCpuSetMems());
+        oldVal = Arrays.stream(cpus).boxed().toArray(Integer[]::new);
         Arrays.sort(oldVal);
         cpusstr = getStringVal("cpuset.mems.effective");
         newVal = CgroupMetricsTester.convertCpuSetsToArray(cpusstr);
@@ -405,7 +402,16 @@
         }
 
         verifyNotSupported(metrics.getCpuSetMemoryPressure());
-        Asserts.assertFalse(metrics.isCpuSetMemoryPressureEnabled(), "Should be not supported");
+        Asserts.assertNull(metrics.isCpuSetMemoryPressureEnabled(), "Should be not supported");
+    }
+
+    private int[] mapNullToEmpty(int[] cpus) {
+        if (cpus == null) {
+            // Not available. For sake of testing continue with an
+            // empty array.
+            cpus = new int[0];
+        }
+        return cpus;
     }
 
     @Override
@@ -467,7 +473,45 @@
 
     @Override
     public void testMisc() {
-        // nothing for cgroups v2
+        testIOStat();
     }
 
+    private void testIOStat() {
+        Metrics metrics = Metrics.systemMetrics();
+        long oldVal = metrics.getBlkIOServiceCount();
+        long newVal = getIoStatAccumulate(new String[] { "rios", "wios" });
+        if (!CgroupMetricsTester.compareWithErrorMargin(oldVal, newVal)) {
+            fail("io.stat->rios/wios: ", oldVal, newVal);
+        }
+
+        oldVal = metrics.getBlkIOServiced();
+        newVal = getIoStatAccumulate(new String[] { "rbytes", "wbytes" });
+        if (!CgroupMetricsTester.compareWithErrorMargin(oldVal, newVal)) {
+            fail("io.stat->rbytes/wbytes: ", oldVal, newVal);
+        }
+    }
+
+    private long getIoStatAccumulate(String[] matchNames) {
+        try {
+            return Files.lines(Paths.get(UNIFIED.getPath(), "io.stat"))
+                    .map(line -> {
+                        long accumulator = 0;
+                        String[] tokens = line.split("\\s+");
+                        for (String t: tokens) {
+                            String[] keyVal = t.split("=");
+                            if (keyVal.length != 2) {
+                                continue;
+                            }
+                            for (String match: matchNames) {
+                                if (match.equals(keyVal[0])) {
+                                    accumulator += Long.parseLong(keyVal[1]);
+                                }
+                            }
+                        }
+                        return accumulator;
+                    }).collect(Collectors.summingLong(e -> e));
+        } catch (IOException e) {
+            return Metrics.LONG_RETVAL_NOT_SUPPORTED;
+        }
+    }
 }