| /** |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.apache.hadoop.hbase.util; |
| |
| import java.lang.reflect.Field; |
| import java.lang.reflect.Method; |
| import java.security.AccessController; |
| import java.security.PrivilegedAction; |
| |
| import org.apache.yetus.audience.InterfaceAudience; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| @InterfaceAudience.Private |
| public class UnsafeAvailChecker { |
| |
| private static final String CLASS_NAME = "sun.misc.Unsafe"; |
| private static final Logger LOG = LoggerFactory.getLogger(UnsafeAvailChecker.class); |
| private static boolean avail = false; |
| private static boolean unaligned = false; |
| |
| static { |
| avail = AccessController.doPrivileged(new PrivilegedAction<Boolean>() { |
| @Override |
| public Boolean run() { |
| try { |
| Class<?> clazz = Class.forName(CLASS_NAME); |
| Field f = clazz.getDeclaredField("theUnsafe"); |
| f.setAccessible(true); |
| Object theUnsafe = f.get(null); |
| if (theUnsafe == null) { |
| LOG.warn("Could not get static instance from sun.misc.Unsafe"); |
| return false; |
| } |
| // Check for availability of all methods used by UnsafeAccess |
| Method m; |
| try { |
| m = clazz.getDeclaredMethod("arrayBaseOffset", Class.class); |
| if (m == null) { |
| LOG.warn("sun.misc.Unsafe is missing arrayBaseOffset(Class)"); |
| return false; |
| } |
| m = clazz.getDeclaredMethod("copyMemory", Object.class, long.class, Object.class, |
| long.class, long.class); |
| if (m == null) { |
| LOG.warn("sun.misc.Unsafe is missing copyMemory(Object,long,Object,long,long)"); |
| return false; |
| } |
| m = clazz.getDeclaredMethod("getByte", Object.class, long.class); |
| if (m == null) { |
| LOG.warn("sun.misc.Unsafe is missing getByte(Object,long)"); |
| return false; |
| } |
| m = clazz.getDeclaredMethod("getShort", long.class); |
| if (m == null) { |
| LOG.warn("sun.misc.Unsafe is missing getShort(long)"); |
| return false; |
| } |
| m = clazz.getDeclaredMethod("getShort", Object.class, long.class); |
| if (m == null) { |
| LOG.warn("sun.misc.Unsafe is missing getShort(Object,long)"); |
| return false; |
| } |
| m = clazz.getDeclaredMethod("getInt", long.class); |
| if (m == null) { |
| LOG.warn("sun.misc.Unsafe is missing getInt(long)"); |
| return false; |
| } |
| m = clazz.getDeclaredMethod("getInt", Object.class, long.class); |
| if (m == null) { |
| LOG.warn("sun.misc.Unsafe is missing getInt(Object,long)"); |
| return false; |
| } |
| m = clazz.getDeclaredMethod("getLong", long.class); |
| if (m == null) { |
| LOG.warn("sun.misc.Unsafe is missing getLong(long)"); |
| return false; |
| } |
| m = clazz.getDeclaredMethod("getLong", Object.class, long.class); |
| if (m == null) { |
| LOG.warn("sun.misc.Unsafe is missing getLong(Object,long)"); |
| return false; |
| } |
| m = clazz.getDeclaredMethod("putByte", long.class, byte.class); |
| if (m == null) { |
| LOG.warn("sun.misc.Unsafe is missing putByte(long,byte)"); |
| return false; |
| } |
| m = clazz.getDeclaredMethod("putByte", Object.class, long.class, byte.class); |
| if (m == null) { |
| LOG.warn("sun.misc.Unsafe is missing putByte(Object,long,byte)"); |
| return false; |
| } |
| m = clazz.getDeclaredMethod("putShort", long.class, short.class); |
| if (m == null) { |
| LOG.warn("sun.misc.Unsafe is missing putShort(long,short)"); |
| return false; |
| } |
| m = clazz.getDeclaredMethod("putShort", Object.class, long.class, short.class); |
| if (m == null) { |
| LOG.warn("sun.misc.Unsafe is missing putShort(Object,long,short)"); |
| return false; |
| } |
| m = clazz.getDeclaredMethod("putInt", long.class, int.class); |
| if (m == null) { |
| LOG.warn("sun.misc.Unsafe is missing putInt(long,int)"); |
| return false; |
| } |
| m = clazz.getDeclaredMethod("putInt", Object.class, long.class, int.class); |
| if (m == null) { |
| LOG.warn("sun.misc.Unsafe is missing putInt(Object,long,int)"); |
| return false; |
| } |
| m = clazz.getDeclaredMethod("putLong", long.class, long.class); |
| if (m == null) { |
| LOG.warn("sun.misc.Unsafe is missing putLong(long,long)"); |
| return false; |
| } |
| m = clazz.getDeclaredMethod("putLong", Object.class, long.class, long.class); |
| if (m == null) { |
| LOG.warn("sun.misc.Unsafe is missing putLong(Object,long,long)"); |
| return false; |
| } |
| // theUnsafe is accessible and all methods are available |
| return true; |
| } catch (Throwable e) { |
| LOG.warn("sun.misc.Unsafe is missing one or more required methods", e); |
| } |
| } catch (Throwable e) { |
| LOG.warn("sun.misc.Unsafe is not available/accessible", e); |
| } |
| return false; |
| } |
| }); |
| // When Unsafe itself is not available/accessible consider unaligned as false. |
| if (avail) { |
| String arch = System.getProperty("os.arch"); |
| if ("ppc64".equals(arch) || "ppc64le".equals(arch) || "aarch64".equals(arch)) { |
| // java.nio.Bits.unaligned() wrongly returns false on ppc (JDK-8165231), |
| unaligned = true; |
| } else { |
| try { |
| // Using java.nio.Bits#unaligned() to check for unaligned-access capability |
| Class<?> clazz = Class.forName("java.nio.Bits"); |
| Method m = clazz.getDeclaredMethod("unaligned"); |
| m.setAccessible(true); |
| unaligned = (Boolean) m.invoke(null); |
| } catch (Exception e) { |
| LOG.warn("java.nio.Bits#unaligned() check failed." |
| + "Unsafe based read/write of primitive types won't be used", e); |
| } |
| } |
| } |
| } |
| |
| /** |
| * @return true when running JVM is having sun's Unsafe package available in it and it is |
| * accessible. |
| */ |
| public static boolean isAvailable() { |
| return avail; |
| } |
| |
| /** |
| * @return true when running JVM is having sun's Unsafe package available in it and underlying |
| * system having unaligned-access capability. |
| */ |
| public static boolean unaligned() { |
| return unaligned; |
| } |
| |
| private UnsafeAvailChecker() { |
| // private constructor to avoid instantiation |
| } |
| } |