8242313: use reproducible random in hotspot svc tests

Reviewed-by: cjplummer

test/hotspot/jtreg/serviceability/sa/LingeredAppWithNativeMethod.java

@@ -1,6 +1,6 @@
 
 /*
- * Copyright (c) 2018, 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
@@ -22,13 +22,16 @@
  * questions.
  */
 
+import java.util.Random;
 import jdk.test.lib.apps.LingeredApp;
+import jdk.test.lib.Utils;
 
 public class LingeredAppWithNativeMethod extends LingeredApp {
 
     public static final String THREAD_NAME = "NoFramePointerJNIFib";
     private static final int UPPER_BOUND = 55;
     private static final int LOWER_BOUND = 40;
+    private static final Random RNG = Utils.getRandomInstance();
 
     static {
         // JNI library compiled with no frame pointer info
@@ -43,9 +46,9 @@ public void callNative() {
         // Results of fibonacci calculation from JNI are
         // reported via callback(). That's where the process
         // of calculating fibonacci restarts.
-        int num = (int) (Math.random() * UPPER_BOUND);
+        int num = (int) (RNG.nextDouble() * UPPER_BOUND);
         while (num < LOWER_BOUND) {
-            num = (int) (Math.random() * UPPER_BOUND);
+            num = (int) (RNG.nextDouble() * UPPER_BOUND);
         }
         System.out.print("fib(" + num + ") = ");
         callJNI(this, num);

test/hotspot/jtreg/serviceability/sa/TestJhsdbJstackMixed.java

@@ -34,6 +34,7 @@
 
 /**
  * @test
+ * @key randomness
  * @bug 8208091
  * @requires (os.family == "linux") & (vm.hasSA)
  * @library /test/lib

test/hotspot/jtreg/serviceability/threads/TestFalseDeadLock.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013, 2016, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2013, 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
@@ -28,6 +28,7 @@
 
 /*
  * @test
+ * @key randomness
  * @bug 8016304
  * @summary Make sure no deadlock is reported for this program which has no deadlocks.
  * @modules java.base/jdk.internal.misc
@@ -48,8 +49,9 @@ public class TestFalseDeadLock {
     public static void main(String[] args) throws Exception {
         bean = ManagementFactory.getThreadMXBean();
         Thread[] threads = new Thread[500];
+        Random random = Utils.getRandomInstance();
         for (int i = 0; i < threads.length; i++) {
-            Test t = new Test();
+            Test t = new Test(random.nextLong());
             threads[i] = new Thread(t);
             threads[i].start();
         }
@@ -67,8 +69,12 @@ public static void main(String[] args) throws Exception {
     }
 
     public static class Test implements Runnable {
+        private final long seed;
+        public Test(long seed) {
+            this.seed = seed;
+        }
         public void run() {
-            Random r = Utils.getRandomInstance();
+            Random r = new Random(seed);
             while (running) {
                 try {
                     synchronized (this) {