1 /* 2 * Copyright (c) 2014, Oracle 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 /* 25 * @test 26 * @summary Test corner case that overflows malloc site hashtable bucket 27 * @requires sun.arch.data.model == "32" 28 * @key nmt jcmd stress 29 * @library /testlibrary /testlibrary/whitebox 30 * @ignore 8062870 31 * @build MallocSiteHashOverflow 32 * @run main ClassFileInstaller sun.hotspot.WhiteBox 33 * @run main/othervm -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI -XX:NativeMemoryTracking=detail MallocSiteHashOverflow 34 */ 35 36 import com.oracle.java.testlibrary.*; 37 import sun.hotspot.WhiteBox; 38 39 public class MallocSiteHashOverflow { 40 41 public static void main(String args[]) throws Exception { 42 43 // Size of entries based on malloc tracking header defined in mallocTracker.hpp 44 // For 32-bit systems, create 257 malloc sites with the same hash bucket to overflow a hash bucket 45 long entries = 257; 46 47 OutputAnalyzer output; 48 WhiteBox wb = WhiteBox.getWhiteBox(); 49 int MAX_HASH_SIZE = wb.NMTGetHashSize(); 50 51 // Grab my own PID 52 String pid = Integer.toString(ProcessTools.getProcessId()); 53 ProcessBuilder pb = new ProcessBuilder(); 54 55 // Verify that current tracking level is "detail" 56 pb.command(new String[] { JDKToolFinder.getJDKTool("jcmd"), pid, "VM.native_memory", "statistics"}); 57 output = new OutputAnalyzer(pb.start()); 58 output.shouldContain("Native Memory Tracking Statistics"); 59 60 // Attempt to cause NMT to downgrade tracking level by allocating small amounts 61 // of memory with random pseudo call stack 62 int pc = 1; 63 for (int i = 0; i < entries; i++) { 64 long addr = wb.NMTMallocWithPseudoStack(1, pc); 65 if (addr == 0) { 66 throw new RuntimeException("NMTMallocWithPseudoStack: out of memory"); 67 } 68 // We free memory here since it doesn't affect pseudo malloc alloc site hash table entries 69 wb.NMTFree(addr); 70 pc += MAX_HASH_SIZE; 71 if (i == entries) { 72 // Verify that tracking has been downgraded 73 pb.command(new String[] { JDKToolFinder.getJDKTool("jcmd"), pid, "VM.native_memory", "statistics"}); 74 output = new OutputAnalyzer(pb.start()); 75 output.shouldContain("Tracking level has been downgraded due to lack of resources"); 76 } 77 } 78 } 79 }