1/* 2 * Copyright (c) 2005, 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 * @bug 6302839 27 * @summary SecurityRace System field accesses in two threads 28 * @author Pete Soper 29 * @build SecurityRace 30 * @run main/othervm/policy=System.policy SecurityRace 31 */ 32 33/* 34 * By default the test runs for a very short time. Use main arg "stress" 35 * to have a real chance of exposing races. Use main arg "time" to report 36 * the average nanoseconds per invocation of System.setSecurityManager and 37 * System.getSecurityManager. No testing for access races is performed with 38 * argument "time." 39 * 40 * Requires security permissions "setSecurityManager" and 41 * "createSecurityManager." 42 */ 43 44 45 46public class SecurityRace implements Runnable { 47 48 // Number of iterations to "warm up" and get methods compiled/inlined. 49 // (this is conservative) 50 static final int WARMUP_LOOPS = 100000; 51 52 // Number of timing trials 53 static final int TIMING_TRIALS = 10; 54 55 // Seconds to run this in "stress" mode. This is double the average 56 // time to expose the races of bug 6302839 on a Blade 1000. Invoke 57 // the program with the "stress" option multiple times for more 58 // confidence. 59 static final int STRESS_MILLISECONDS = 300000; 60 static final int SET_TIMING_LOOPS = 10000; 61 62 // Max seconds to run before terminating the test ("declaring victory"). 63 static int MAX_MILLISECONDS = 100; 64 65 // Number of iterations to time 66 static final int GET_TIMING_LOOPS = 10000000; 67 68 // Set true by main thread when NPE caught or time to terminate. 69 // Set true by other thread when NPE caught. It makes 70 // no difference where the NPE is thrown. 71 static volatile boolean stopthreads = false; 72 73 // Number of getProperty invocations between main loop checks 74 static final int GETPROPERTY_LOOPS = 30000; 75 76 // Used by race and timing tests. Must get set non-null at lease once. 77 static SecurityManager sm = new SecurityManager(); 78 79 public static void main(String[] argv) throws Exception { 80 String s; 81 82 if (argv.length > 0) { 83 if (argv[0].equals("time")) { 84 85 // Run the timing method 86 // First warm up the method to make sure it gets compiled 87 for (int i = 0; i < WARMUP_LOOPS; i++) { 88 timeit(1, 1, 1); 89 } 90 91 System.out.println("boo"); 92 93 // Now do the actual timing 94 timeit(TIMING_TRIALS, GET_TIMING_LOOPS, SET_TIMING_LOOPS); 95 } else if (argv[0].equals("stress")) { 96 97 // For stress test the test duration is boosted 98 MAX_MILLISECONDS = STRESS_MILLISECONDS; 99 } else { 100 throw new RuntimeException( 101 "SecurityRace: " + argv[0] 102 + " argument to main not recognized"); 103 } // if argv 104 } // if length 105 106 long start = System.currentTimeMillis(), 107 end = start + MAX_MILLISECONDS; 108 109 // Create and start racing thread 110 (new Thread(new SecurityRace())).start(); 111 112 // main thread alternates batches of getProperty() with time checks 113 try { 114 do { 115 if (stopthreads) { 116 117 // other thread suffered an NPE 118 throw new RuntimeException("SecurityRace failed with NPE"); 119 } 120 121 for (int i = 0; i < GETPROPERTY_LOOPS; i++) { 122 s = System.getProperty("java.version"); 123 } 124 } while (System.currentTimeMillis() < end); 125 } catch (NullPointerException e) { 126 throw new RuntimeException("SecurityRace failed with NPE"); 127 } finally { 128 129 // make sure other thread terminates 130 stopthreads = true; 131 } 132 } // main 133 134 // System.security mutator. 135 public void run() { 136 try { 137 while (true) { 138 if (stopthreads) { 139 return; 140 } 141 142 System.setSecurityManager(sm); 143 144 // The goal is to catch another thread testing the 145 // value set above and trying to use it after it's 146 // nulled below. 147 System.setSecurityManager(null); 148 } 149 } catch (NullPointerException e) { 150 stopthreads = true; 151 152 return; 153 } 154 } 155 156 // Time method execution. Collects trials number of timings 157 // for the number of accessor and mutator invocation loops 158 // specified. 159 public static void timeit(int timing_trials, int get_timing_loops, 160 int set_timing_loops) { 161 try { 162 long start; 163 164 // Time the methods and report average. 165 // Time multiple trials so noise is apparent and a 166 // T test can be used to establish significance. 167 for (int j = 0; j < timing_trials; j++) { 168 start = System.nanoTime(); 169 170 for (int i = 0; i < get_timing_loops; i++) { 171 sm = System.getSecurityManager(); 172 } 173 174 // Don't print for "warmup" case. This might mean that 175 // the compiler fails to compile the println (setting it 176 // up to execute via interpretation using an "uncommon trap") 177 // but we don't care if this println runs slowly! 178 if (timing_trials > 1) { 179 System.out.println((float) (System.nanoTime() - start) 180 / (float) get_timing_loops); 181 } 182 } 183 184 for (int j = 0; j < timing_trials; j++) { 185 start = System.nanoTime(); 186 187 for (int i = 0; i < set_timing_loops; i++) { 188 System.setSecurityManager(sm); 189 } 190 191 if (timing_trials > 1) { 192 System.out.println((float) (System.nanoTime() - start) 193 / (float) set_timing_loops); 194 } 195 } 196 197 return; 198 } catch (Exception e) { 199 throw new RuntimeException("SecurityRace got unexpected: " + e); 200 } 201 } // timeit 202} // SecurityRace 203