1 /* 2 * Copyright (c) 2014, 2019, 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 package jdk.vm.ci.common; 24 25 import java.util.concurrent.atomic.AtomicInteger; 26 27 import jdk.vm.ci.services.Services; 28 29 /** 30 * A facility for timing a step in the runtime initialization sequence. This is independent from all 31 * other JVMCI code so as to not perturb the initialization sequence. It is enabled by setting the 32 * {@code "jvmci.inittimer"} system property to {@code "true"}. 33 */ 34 public final class InitTimer implements AutoCloseable { 35 private final String name; 36 private final long start; 37 38 private InitTimer(String name) { 39 int n = nesting.getAndIncrement(); 40 if (n == 0) { 41 initializingThread = Thread.currentThread(); 42 System.out.println("INITIALIZING THREAD: " + initializingThread); 43 } else { 44 assert Thread.currentThread() == initializingThread : Thread.currentThread() + " != " + initializingThread; 45 } 46 this.name = name; 47 this.start = System.currentTimeMillis(); 48 System.out.println("START: " + SPACES.substring(0, n * 2) + name); 49 } 50 51 @Override 52 @SuppressFBWarnings(value = "ST_WRITE_TO_STATIC_FROM_INSTANCE_METHOD", justification = "only the initializing thread accesses this field") 53 public void close() { 54 final long end = System.currentTimeMillis(); 55 int n = nesting.decrementAndGet(); 56 System.out.println(" DONE: " + SPACES.substring(0, n * 2) + name + " [" + (end - start) + " ms]"); 57 if (n == 0) { 58 initializingThread = null; 59 } 60 } 61 62 public static InitTimer timer(String name) { 63 return isEnabled() ? new InitTimer(name) : null; 64 } 65 66 public static InitTimer timer(String name, Object suffix) { 67 return isEnabled() ? new InitTimer(name + suffix) : null; 68 } 69 70 /** 71 * Determines if initialization timing is enabled. Note: This property cannot use 72 * {@code HotSpotJVMCIRuntime.Option} since that class is not visible from this package. 73 */ 74 private static boolean isEnabled() { 75 if (enabledPropertyValue == null) { 76 enabledPropertyValue = Boolean.parseBoolean(Services.getSavedProperty("jvmci.InitTimer")); 77 nesting = new AtomicInteger(); 78 } 79 return enabledPropertyValue; 80 } 81 82 /** 83 * Cache for value of {@code jvmci.InitTimer} system property. 84 */ 85 @NativeImageReinitialize private static Boolean enabledPropertyValue; 86 87 private static AtomicInteger nesting; 88 private static final String SPACES = " "; 89 90 /** 91 * Used to assert the invariant that all related initialization happens on the same thread. 92 */ 93 static Thread initializingThread; 94 }