1 /* 2 * Copyright (c) 2017, Google and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 */ 23 24 package MyPackage; 25 26 /** 27 * @test 28 * @summary Verifies if turning on/off/on the monitor wipes out the information. 29 * @build Frame 30 * @compile HeapMonitorOnOffTest.java 31 * @run main/othervm/native -agentlib:HeapMonitor MyPackage.HeapMonitorOnOffTest 32 */ 33 34 public class HeapMonitorOnOffTest { 35 static { 36 try { 37 System.loadLibrary("HeapMonitor"); 38 } catch (UnsatisfiedLinkError ule) { 39 System.err.println("Could not load HeapMonitor library"); 40 System.err.println("java.library.path: " 41 + System.getProperty("java.library.path")); 42 throw ule; 43 } 44 } 45 46 private static int g_tmp[]; 47 48 private static int helper() { 49 int sum = 0; 50 // Let us assume that the array is 24 bytes of memory. 51 for (int i = 0; i < 127000 / 6; i++) { 52 int tmp[] = new int[1]; 53 // Force it to be kept. 54 g_tmp = tmp; 55 sum += g_tmp[0]; 56 } 57 return sum; 58 } 59 60 private static void wrapper() { 61 int sum = 0; 62 for (int j = 0; j < 1000; j++) { 63 sum += helper(); 64 } 65 System.out.println(sum); 66 } 67 68 private native static int checkFrames(Frame[] frames); 69 private native static int checkWipeOut(Frame[] frames); 70 private native static int enableSampling(); 71 private native static int disableSampling(); 72 73 public static void main(String[] args) { 74 Frame[] frames = new Frame[3]; 75 frames[0] = new Frame("helper", "()I", "HeapMonitorOnOffTest.java", 52); 76 frames[1] = new Frame("wrapper", "()V", "HeapMonitorOnOffTest.java", 63); 77 frames[2] = new Frame("main", "([Ljava/lang/String;)V", "HeapMonitorOnOffTest.java", 81); 78 79 // Enable sampling and allocate. 80 enableSampling(); 81 wrapper(); 82 83 // Now disable and re-enable. 84 disableSampling(); 85 86 // Check that the data is still there: this allows to peruse samples after profiling. 87 int status = checkFrames(frames); 88 if (status != 0) { 89 throw new RuntimeException("Failed to find the traces before the wipe out."); 90 } 91 92 // Enabling the sampling should wipe everything out. 93 enableSampling(); 94 95 status = checkWipeOut(frames); 96 if (status != 0) { 97 throw new RuntimeException("Failed to wipe out the information."); 98 } 99 } 100 }