--- a/jdk/src/java.base/share/classes/sun/misc/Perf.java Thu Jan 14 08:08:19 2016 -0800
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,538 +0,0 @@
-/*
- * Copyright (c) 2002, 2006, Oracle and/or its affiliates. All rights reserved.
- * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
- *
- * This code is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License version 2 only, as
- * published by the Free Software Foundation. Oracle designates this
- * particular file as subject to the "Classpath" exception as provided
- * by Oracle in the LICENSE file that accompanied this code.
- *
- * This code is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
- * version 2 for more details (a copy is included in the LICENSE file that
- * accompanied this code).
- *
- * You should have received a copy of the GNU General Public License version
- * 2 along with this work; if not, write to the Free Software Foundation,
- * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
- *
- * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
- * or visit www.oracle.com if you need additional information or have any
- * questions.
- */
-package sun.misc;
-
-import java.nio.ByteBuffer;
-import java.security.Permission;
-import java.security.PrivilegedAction;
-import java.io.IOException;
-import java.io.UnsupportedEncodingException;
-
-/**
- * The Perf class provides the ability to attach to an instrumentation
- * buffer maintained by a Java virtual machine. The instrumentation
- * buffer may be for the Java virtual machine running the methods of
- * this class or it may be for another Java virtual machine on the
- * same system.
- * <p>
- * In addition, this class provides methods to create instrumentation
- * objects in the instrumentation buffer for the Java virtual machine
- * that is running these methods. It also contains methods for acquiring
- * the value of a platform specific high resolution clock for time
- * stamp and interval measurement purposes.
- *
- * @author Brian Doherty
- * @since 1.4.2
- * @see #getPerf
- * @see sun.misc.Perf$GetPerfAction
- * @see java.nio.ByteBuffer
- */
-public final class Perf {
-
- private static Perf instance;
-
- private static final int PERF_MODE_RO = 0;
- private static final int PERF_MODE_RW = 1;
-
- private Perf() { } // prevent instantiation
-
- /**
- * The GetPerfAction class is a convenience class for acquiring access
- * to the singleton Perf instance using the
- * <code>AccessController.doPrivileged()</code> method.
- * <p>
- * An instance of this class can be used as the argument to
- * <code>AccessController.doPrivileged(PrivilegedAction)</code>.
- * <p> Here is a suggested idiom for use of this class:
- *
- * <blockquote><pre>{@code
- * class MyTrustedClass {
- * private static final Perf perf =
- * AccessController.doPrivileged(new Perf.GetPerfAction<Perf>());
- * ...
- * }
- * }</pre></blockquote>
- * <p>
- * In the presence of a security manager, the <code>MyTrustedClass</code>
- * class in the above example will need to be granted the
- * <em>"sun.misc.Perf.getPerf"</em> <code>RuntimePermission</code>
- * permission in order to successfully acquire the singleton Perf instance.
- * <p>
- * Please note that the <em>"sun.misc.Perf.getPerf"</em> permission
- * is not a JDK specified permission.
- *
- * @see java.security.AccessController#doPrivileged(PrivilegedAction)
- * @see java.lang.RuntimePermission
- */
- public static class GetPerfAction implements PrivilegedAction<Perf>
- {
- /**
- * Run the <code>Perf.getPerf()</code> method in a privileged context.
- *
- * @see #getPerf
- */
- public Perf run() {
- return getPerf();
- }
- }
-
- /**
- * Return a reference to the singleton Perf instance.
- * <p>
- * The getPerf() method returns the singleton instance of the Perf
- * class. The returned object provides the caller with the capability
- * for accessing the instrumentation buffer for this or another local
- * Java virtual machine.
- * <p>
- * If a security manager is installed, its <code>checkPermission</code>
- * method is called with a <code>RuntimePermission</code> with a target
- * of <em>"sun.misc.Perf.getPerf"</em>. A security exception will result
- * if the caller has not been granted this permission.
- * <p>
- * Access to the returned <code>Perf</code> object should be protected
- * by its caller and not passed on to untrusted code. This object can
- * be used to attach to the instrumentation buffer provided by this Java
- * virtual machine or for those of other Java virtual machines running
- * on the same system. The instrumentation buffer may contain senstitive
- * information. API's built on top of this interface may want to provide
- * finer grained access control to the contents of individual
- * instrumentation objects contained within the buffer.
- * <p>
- * Please note that the <em>"sun.misc.Perf.getPerf"</em> permission
- * is not a JDK specified permission.
- *
- * @return A reference to the singleton Perf instance.
- * @throws AccessControlException if a security manager exists and
- * its <code>checkPermission</code> method doesn't allow
- * access to the <em>"sun.misc.Perf.getPerf"</em> target.
- * @see java.lang.RuntimePermission
- * @see #attach
- */
- public static Perf getPerf()
- {
- SecurityManager security = System.getSecurityManager();
- if (security != null) {
- Permission perm = new RuntimePermission("sun.misc.Perf.getPerf");
- security.checkPermission(perm);
- }
-
- return instance;
- }
-
- /**
- * Attach to the instrumentation buffer for the specified Java virtual
- * machine.
- * <p>
- * This method will attach to the instrumentation buffer for the
- * specified virtual machine. It returns a <code>ByteBuffer</code> object
- * that is initialized to access the instrumentation buffer for the
- * indicated Java virtual machine. The <code>lvmid</code> parameter is
- * a integer value that uniquely identifies the target local Java virtual
- * machine. It is typically, but not necessarily, the process id of
- * the target Java virtual machine.
- * <p>
- * If the <code>lvmid</code> identifies a Java virtual machine different
- * from the one running this method, then the coherency characteristics
- * of the buffer are implementation dependent. Implementations that do
- * not support named, coherent, shared memory may return a
- * <code>ByteBuffer</code> object that contains only a snap shot of the
- * data in the instrumentation buffer. Implementations that support named,
- * coherent, shared memory, may return a <code>ByteBuffer</code> object
- * that will be changing dynamically over time as the target Java virtual
- * machine updates its mapping of this buffer.
- * <p>
- * If the <code>lvmid</code> is 0 or equal to the actual <code>lvmid</code>
- * for the Java virtual machine running this method, then the returned
- * <code>ByteBuffer</code> object will always be coherent and dynamically
- * changing.
- * <p>
- * The attach mode specifies the access permissions requested for the
- * instrumentation buffer of the target virtual machine. The permitted
- * access permissions are:
- * <ul>
- * <li>"r" - Read only access. This Java virtual machine has only
- * read access to the instrumentation buffer for the target Java
- * virtual machine.
- * <li>"rw" - Read/Write access. This Java virtual machine has read and
- * write access to the instrumentation buffer for the target Java virtual
- * machine. This mode is currently not supported and is reserved for
- * future enhancements.
- * </ul>
- *
- * @param lvmid an integer that uniquely identifies the
- * target local Java virtual machine.
- * @param mode a string indicating the attach mode.
- * @return ByteBuffer a direct allocated byte buffer
- * @throws IllegalArgumentException The lvmid or mode was invalid.
- * @throws IOException An I/O error occurred while trying to acquire
- * the instrumentation buffer.
- * @throws OutOfMemoryError The instrumentation buffer could not be mapped
- * into the virtual machine's address space.
- * @see java.nio.ByteBuffer
- */
- public ByteBuffer attach(int lvmid, String mode)
- throws IllegalArgumentException, IOException
- {
- if (mode.compareTo("r") == 0) {
- return attachImpl(null, lvmid, PERF_MODE_RO);
- }
- else if (mode.compareTo("rw") == 0) {
- return attachImpl(null, lvmid, PERF_MODE_RW);
- }
- else {
- throw new IllegalArgumentException("unknown mode");
- }
- }
-
- /**
- * Attach to the instrumentation buffer for the specified Java virtual
- * machine owned by the given user.
- * <p>
- * This method behaves just as the <code>attach(int lvmid, String mode)
- * </code> method, except that it only searches for Java virtual machines
- * owned by the specified user.
- *
- * @param user A <code>String</code> object containing the
- * name of the user that owns the target Java
- * virtual machine.
- * @param lvmid an integer that uniquely identifies the
- * target local Java virtual machine.
- * @param mode a string indicating the attach mode.
- * @return ByteBuffer a direct allocated byte buffer
- * @throws IllegalArgumentException The lvmid or mode was invalid.
- * @throws IOException An I/O error occurred while trying to acquire
- * the instrumentation buffer.
- * @throws OutOfMemoryError The instrumentation buffer could not be mapped
- * into the virtual machine's address space.
- * @see java.nio.ByteBuffer
- */
- public ByteBuffer attach(String user, int lvmid, String mode)
- throws IllegalArgumentException, IOException
- {
- if (mode.compareTo("r") == 0) {
- return attachImpl(user, lvmid, PERF_MODE_RO);
- }
- else if (mode.compareTo("rw") == 0) {
- return attachImpl(user, lvmid, PERF_MODE_RW);
- }
- else {
- throw new IllegalArgumentException("unknown mode");
- }
- }
-
- /**
- * Call the implementation specific attach method.
- * <p>
- * This method calls into the Java virtual machine to perform the platform
- * specific attach method. Buffers returned from this method are
- * internally managed as <code>PhantomRefereces</code> to provide for
- * guaranteed, secure release of the native resources.
- *
- * @param user A <code>String</code> object containing the
- * name of the user that owns the target Java
- * virtual machine.
- * @param lvmid an integer that uniquely identifies the
- * target local Java virtual machine.
- * @param mode a string indicating the attach mode.
- * @return ByteBuffer a direct allocated byte buffer
- * @throws IllegalArgumentException The lvmid or mode was invalid.
- * @throws IOException An I/O error occurred while trying to acquire
- * the instrumentation buffer.
- * @throws OutOfMemoryError The instrumentation buffer could not be mapped
- * into the virtual machine's address space.
- */
- private ByteBuffer attachImpl(String user, int lvmid, int mode)
- throws IllegalArgumentException, IOException
- {
- final ByteBuffer b = attach(user, lvmid, mode);
-
- if (lvmid == 0) {
- // The native instrumentation buffer for this Java virtual
- // machine is never unmapped.
- return b;
- }
- else {
- // This is an instrumentation buffer for another Java virtual
- // machine with native resources that need to be managed. We
- // create a duplicate of the native ByteBuffer and manage it
- // with a Cleaner object (PhantomReference). When the duplicate
- // becomes only phantomly reachable, the native resources will
- // be released.
-
- final ByteBuffer dup = b.duplicate();
- Cleaner.create(dup, new Runnable() {
- public void run() {
- try {
- instance.detach(b);
- }
- catch (Throwable th) {
- // avoid crashing the reference handler thread,
- // but provide for some diagnosability
- assert false : th.toString();
- }
- }
- });
- return dup;
- }
- }
-
- /**
- * Native method to perform the implementation specific attach mechanism.
- * <p>
- * The implementation of this method may return distinct or identical
- * <code>ByteBuffer</code> objects for two distinct calls requesting
- * attachment to the same Java virtual machine.
- * <p>
- * For the Sun HotSpot JVM, two distinct calls to attach to the same
- * target Java virtual machine will result in two distinct ByteBuffer
- * objects returned by this method. This may change in a future release.
- *
- * @param user A <code>String</code> object containing the
- * name of the user that owns the target Java
- * virtual machine.
- * @param lvmid an integer that uniquely identifies the
- * target local Java virtual machine.
- * @param mode a string indicating the attach mode.
- * @return ByteBuffer a direct allocated byte buffer
- * @throws IllegalArgumentException The lvmid or mode was invalid.
- * @throws IOException An I/O error occurred while trying to acquire
- * the instrumentation buffer.
- * @throws OutOfMemoryError The instrumentation buffer could not be mapped
- * into the virtual machine's address space.
- */
- private native ByteBuffer attach(String user, int lvmid, int mode)
- throws IllegalArgumentException, IOException;
-
- /**
- * Native method to perform the implementation specific detach mechanism.
- * <p>
- * If this method is passed a <code>ByteBuffer</code> object that is
- * not created by the <code>attach</code> method, then the results of
- * this method are undefined, with unpredictable and potentially damaging
- * effects to the Java virtual machine. To prevent accidental or malicious
- * use of this method, all native ByteBuffer created by the <code>
- * attach</code> method are managed internally as PhantomReferences
- * and resources are freed by the system.
- * <p>
- * If this method is passed a <code>ByteBuffer</code> object created
- * by the <code>attach</code> method with a lvmid for the Java virtual
- * machine running this method (lvmid=0, for example), then the detach
- * request is silently ignored.
- *
- * @param ByteBuffer A direct allocated byte buffer created by the
- * <code>attach</code> method.
- * @see java.nio.ByteBuffer
- * @see #attach
- */
- private native void detach(ByteBuffer bb);
-
- /**
- * Create a <code>long</code> scalar entry in the instrumentation buffer
- * with the given variability characteristic, units, and initial value.
- * <p>
- * Access to the instrument is provided through the returned <code>
- * ByteBuffer</code> object. Typically, this object should be wrapped
- * with <code>LongBuffer</code> view object.
- *
- * @param variability the variability characteristic for this entry.
- * @param units the units for this entry.
- * @param name the name of this entry.
- * @param value the initial value for this entry.
- * @return ByteBuffer a direct allocated ByteBuffer object that
- * allows write access to a native memory location
- * containing a <code>long</code> value.
- *
- * see sun.misc.perf.Variability
- * see sun.misc.perf.Units
- * @see java.nio.ByteBuffer
- */
- public native ByteBuffer createLong(String name, int variability,
- int units, long value);
-
- /**
- * Create a <code>String</code> entry in the instrumentation buffer with
- * the given variability characteristic, units, and initial value.
- * <p>
- * The maximum length of the <code>String</code> stored in this string
- * instrument is given in by <code>maxLength</code> parameter. Updates
- * to this instrument with <code>String</code> values with lengths greater
- * than <code>maxLength</code> will be truncated to <code>maxLength</code>.
- * The truncated value will be terminated by a null character.
- * <p>
- * The underlying implementation may further limit the length of the
- * value, but will continue to preserve the null terminator.
- * <p>
- * Access to the instrument is provided through the returned <code>
- * ByteBuffer</code> object.
- *
- * @param variability the variability characteristic for this entry.
- * @param units the units for this entry.
- * @param name the name of this entry.
- * @param value the initial value for this entry.
- * @param maxLength the maximum string length for this string
- * instrument.
- * @return ByteBuffer a direct allocated ByteBuffer that allows
- * write access to a native memory location
- * containing a <code>long</code> value.
- *
- * see sun.misc.perf.Variability
- * see sun.misc.perf.Units
- * @see java.nio.ByteBuffer
- */
- public ByteBuffer createString(String name, int variability,
- int units, String value, int maxLength)
- {
- byte[] v = getBytes(value);
- byte[] v1 = new byte[v.length+1];
- System.arraycopy(v, 0, v1, 0, v.length);
- v1[v.length] = '\0';
- return createByteArray(name, variability, units, v1, Math.max(v1.length, maxLength));
- }
-
- /**
- * Create a <code>String</code> entry in the instrumentation buffer with
- * the given variability characteristic, units, and initial value.
- * <p>
- * The maximum length of the <code>String</code> stored in this string
- * instrument is implied by the length of the <code>value</code> parameter.
- * Subsequent updates to the value of this instrument will be truncated
- * to this implied maximum length. The truncated value will be terminated
- * by a null character.
- * <p>
- * The underlying implementation may further limit the length of the
- * initial or subsequent value, but will continue to preserve the null
- * terminator.
- * <p>
- * Access to the instrument is provided through the returned <code>
- * ByteBuffer</code> object.
- *
- * @param variability the variability characteristic for this entry.
- * @param units the units for this entry.
- * @param name the name of this entry.
- * @param value the initial value for this entry.
- * @return ByteBuffer a direct allocated ByteBuffer that allows
- * write access to a native memory location
- * containing a <code>long</code> value.
- *
- * see sun.misc.perf.Variability
- * see sun.misc.perf.Units
- * @see java.nio.ByteBuffer
- */
- public ByteBuffer createString(String name, int variability,
- int units, String value)
- {
- byte[] v = getBytes(value);
- byte[] v1 = new byte[v.length+1];
- System.arraycopy(v, 0, v1, 0, v.length);
- v1[v.length] = '\0';
- return createByteArray(name, variability, units, v1, v1.length);
- }
-
- /**
- * Create a <code>byte</code> vector entry in the instrumentation buffer
- * with the given variability characteristic, units, and initial value.
- * <p>
- * The <code>maxLength</code> parameter limits the size of the byte
- * array instrument such that the initial or subsequent updates beyond
- * this length are silently ignored. No special handling of truncated
- * updates is provided.
- * <p>
- * The underlying implementation may further limit the length of the
- * length of the initial or subsequent value.
- * <p>
- * Access to the instrument is provided through the returned <code>
- * ByteBuffer</code> object.
- *
- * @param variability the variability characteristic for this entry.
- * @param units the units for this entry.
- * @param name the name of this entry.
- * @param value the initial value for this entry.
- * @param maxLength the maximum length of this byte array.
- * @return ByteBuffer a direct allocated byte buffer that allows
- * write access to a native memory location
- * containing a <code>long</code> value.
- *
- * see sun.misc.perf.Variability
- * see sun.misc.perf.Units
- * @see java.nio.ByteBuffer
- */
- public native ByteBuffer createByteArray(String name, int variability,
- int units, byte[] value,
- int maxLength);
-
-
- /**
- * convert string to an array of UTF-8 bytes
- */
- private static byte[] getBytes(String s)
- {
- byte[] bytes = null;
-
- try {
- bytes = s.getBytes("UTF-8");
- }
- catch (UnsupportedEncodingException e) {
- // ignore, UTF-8 encoding is always known
- }
-
- return bytes;
- }
-
- /**
- * Return the value of the High Resolution Counter.
- *
- * The High Resolution Counter returns the number of ticks since
- * since the start of the Java virtual machine. The resolution of
- * the counter is machine dependent and can be determined from the
- * value return by the {@link #highResFrequency} method.
- *
- * @return the number of ticks of machine dependent resolution since
- * the start of the Java virtual machine.
- *
- * @see #highResFrequency
- * @see java.lang.System#currentTimeMillis()
- */
- public native long highResCounter();
-
- /**
- * Returns the frequency of the High Resolution Counter, in ticks per
- * second.
- *
- * This value can be used to convert the value of the High Resolution
- * Counter, as returned from a call to the {@link #highResCounter} method,
- * into the number of seconds since the start of the Java virtual machine.
- *
- * @return the frequency of the High Resolution Counter.
- * @see #highResCounter
- */
- public native long highResFrequency();
-
- private static native void registerNatives();
-
- static {
- registerNatives();
- instance = new Perf();
- }
-}