removed deprecated objects
parent
47becf1ee5
commit
ece03dbb96
@ -1,216 +0,0 @@
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/**
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* Copyright 2016 Nikita Koksharov
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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/*
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* Written by Doug Lea with assistance from members of JCP JSR-166
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* Expert Group and released to the public domain, as explained at
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* http://creativecommons.org/publicdomain/zero/1.0/
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*/
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package org.redisson.misc;
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import java.io.IOException;
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import java.io.ObjectInputStream;
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import java.io.ObjectOutputStream;
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import java.io.Serializable;
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/**
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* One or more variables that together maintain an initially zero
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* {@code double} sum. When updates (method {@link #add}) are
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* contended across threads, the set of variables may grow dynamically
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* to reduce contention. Method {@link #sum} (or, equivalently {@link
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* #doubleValue}) returns the current total combined across the
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* variables maintaining the sum.
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*
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* <p>This class extends {@link Number}, but does <em>not</em> define
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* methods such as {@code equals}, {@code hashCode} and {@code
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* compareTo} because instances are expected to be mutated, and so are
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* not useful as collection keys.
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*
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* <p><em>jsr166e note: This class is targeted to be placed in
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* java.util.concurrent.atomic.</em>
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*
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* @since 1.8
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* @author Doug Lea
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*/
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public class DoubleAdder extends Striped64 implements Serializable {
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private static final long serialVersionUID = 7249069246863182397L;
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/**
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* Update function. Note that we must use "long" for underlying
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* representations, because there is no compareAndSet for double,
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* due to the fact that the bitwise equals used in any CAS
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* implementation is not the same as double-precision equals.
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* However, we use CAS only to detect and alleviate contention,
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* for which bitwise equals works best anyway. In principle, the
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* long/double conversions used here should be essentially free on
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* most platforms since they just re-interpret bits.
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*
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* Similar conversions are used in other methods.
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*/
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final long fn(long v, long x) {
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return Double.doubleToRawLongBits
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(Double.longBitsToDouble(v) +
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Double.longBitsToDouble(x));
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}
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/**
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* Creates a new adder with initial sum of zero.
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*/
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public DoubleAdder() {
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}
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/**
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* Adds the given value.
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*
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* @param x the value to add
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*/
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public void add(double x) {
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Cell[] as; long b, v; int[] hc; Cell a; int n;
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if ((as = cells) != null ||
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!casBase(b = base,
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Double.doubleToRawLongBits
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(Double.longBitsToDouble(b) + x))) {
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boolean uncontended = true;
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if ((hc = threadHashCode.get()) == null ||
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as == null || (n = as.length) < 1 ||
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(a = as[(n - 1) & hc[0]]) == null ||
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!(uncontended = a.cas(v = a.value,
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Double.doubleToRawLongBits
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(Double.longBitsToDouble(v) + x))))
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retryUpdate(Double.doubleToRawLongBits(x), hc, uncontended);
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}
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}
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/**
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* Returns the current sum. The returned value is <em>NOT</em> an
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* atomic snapshot; invocation in the absence of concurrent
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* updates returns an accurate result, but concurrent updates that
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* occur while the sum is being calculated might not be
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* incorporated. Also, because floating-point arithmetic is not
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* strictly associative, the returned result need not be identical
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* to the value that would be obtained in a sequential series of
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* updates to a single variable.
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*
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* @return the sum
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*/
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public double sum() {
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Cell[] as = cells;
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double sum = Double.longBitsToDouble(base);
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if (as != null) {
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int n = as.length;
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for (int i = 0; i < n; ++i) {
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Cell a = as[i];
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if (a != null)
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sum += Double.longBitsToDouble(a.value);
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}
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}
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return sum;
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}
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/**
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* Resets variables maintaining the sum to zero. This method may
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* be a useful alternative to creating a new adder, but is only
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* effective if there are no concurrent updates. Because this
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* method is intrinsically racy, it should only be used when it is
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* known that no threads are concurrently updating.
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*/
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public void reset() {
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internalReset(0L);
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}
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/**
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* Equivalent in effect to {@link #sum} followed by {@link
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* #reset}. This method may apply for example during quiescent
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* points between multithreaded computations. If there are
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* updates concurrent with this method, the returned value is
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* <em>not</em> guaranteed to be the final value occurring before
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* the reset.
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*
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* @return the sum
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*/
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public double sumThenReset() {
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Cell[] as = cells;
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double sum = Double.longBitsToDouble(base);
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base = 0L;
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if (as != null) {
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int n = as.length;
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for (int i = 0; i < n; ++i) {
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Cell a = as[i];
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if (a != null) {
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long v = a.value;
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a.value = 0L;
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sum += Double.longBitsToDouble(v);
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}
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}
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}
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return sum;
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}
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/**
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* Returns the String representation of the {@link #sum}.
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* @return the String representation of the {@link #sum}
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*/
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public String toString() {
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return Double.toString(sum());
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}
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/**
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* Equivalent to {@link #sum}.
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*
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* @return the sum
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*/
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public double doubleValue() {
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return sum();
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}
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/**
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* Returns the {@link #sum} as a {@code long} after a
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* narrowing primitive conversion.
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*/
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public long longValue() {
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return (long)sum();
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}
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/**
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* Returns the {@link #sum} as an {@code int} after a
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* narrowing primitive conversion.
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*/
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public int intValue() {
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return (int)sum();
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}
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/**
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* Returns the {@link #sum} as a {@code float}
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* after a narrowing primitive conversion.
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*/
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public float floatValue() {
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return (float)sum();
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}
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private void writeObject(ObjectOutputStream s) throws IOException {
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s.defaultWriteObject();
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s.writeDouble(sum());
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}
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private void readObject(ObjectInputStream s)
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throws IOException, ClassNotFoundException {
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s.defaultReadObject();
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busy = 0;
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cells = null;
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base = Double.doubleToRawLongBits(s.readDouble());
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}
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}
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@ -1,217 +0,0 @@
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/**
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* Copyright 2016 Nikita Koksharov
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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/*
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* Written by Doug Lea with assistance from members of JCP JSR-166
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* Expert Group and released to the public domain, as explained at
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* http://creativecommons.org/publicdomain/zero/1.0/
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*/
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package org.redisson.misc;
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import java.io.IOException;
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import java.io.ObjectInputStream;
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import java.io.ObjectOutputStream;
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import java.io.Serializable;
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import java.util.concurrent.atomic.AtomicLong;
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/**
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* One or more variables that together maintain an initially zero
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* {@code long} sum. When updates (method {@link #add}) are contended
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* across threads, the set of variables may grow dynamically to reduce
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* contention. Method {@link #sum} (or, equivalently, {@link
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* #longValue}) returns the current total combined across the
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* variables maintaining the sum.
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*
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* <p>This class is usually preferable to {@link AtomicLong} when
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* multiple threads update a common sum that is used for purposes such
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* as collecting statistics, not for fine-grained synchronization
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* control. Under low update contention, the two classes have similar
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* characteristics. But under high contention, expected throughput of
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* this class is significantly higher, at the expense of higher space
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* consumption.
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*
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* <p>This class extends {@link Number}, but does <em>not</em> define
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* methods such as {@code equals}, {@code hashCode} and {@code
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* compareTo} because instances are expected to be mutated, and so are
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* not useful as collection keys.
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*
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* <p><em>jsr166e note: This class is targeted to be placed in
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* java.util.concurrent.atomic.</em>
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*
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* @since 1.8
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* @author Doug Lea
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*/
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public class LongAdder extends Striped64 implements Serializable {
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private static final long serialVersionUID = 7249069246863182397L;
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/**
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* Version of plus for use in retryUpdate
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*/
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final long fn(long v, long x) { return v + x; }
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/**
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* Creates a new adder with initial sum of zero.
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*/
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public LongAdder() {
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}
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/**
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* Adds the given value.
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*
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* @param x the value to add
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*/
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public void add(long x) {
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Cell[] as; long b, v; int[] hc; Cell a; int n;
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if ((as = cells) != null || !casBase(b = base, b + x)) {
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boolean uncontended = true;
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if ((hc = threadHashCode.get()) == null ||
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as == null || (n = as.length) < 1 ||
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(a = as[(n - 1) & hc[0]]) == null ||
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!(uncontended = a.cas(v = a.value, v + x)))
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retryUpdate(x, hc, uncontended);
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}
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}
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/**
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* Equivalent to {@code add(1)}.
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*/
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public void increment() {
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add(1L);
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}
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/**
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* Equivalent to {@code add(-1)}.
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*/
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public void decrement() {
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add(-1L);
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}
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/**
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* Returns the current sum. The returned value is <em>NOT</em> an
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* atomic snapshot; invocation in the absence of concurrent
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* updates returns an accurate result, but concurrent updates that
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* occur while the sum is being calculated might not be
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* incorporated.
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*
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* @return the sum
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*/
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public long sum() {
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long sum = base;
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Cell[] as = cells;
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if (as != null) {
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int n = as.length;
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for (int i = 0; i < n; ++i) {
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Cell a = as[i];
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if (a != null)
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sum += a.value;
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}
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}
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return sum;
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}
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/**
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* Resets variables maintaining the sum to zero. This method may
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* be a useful alternative to creating a new adder, but is only
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* effective if there are no concurrent updates. Because this
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* method is intrinsically racy, it should only be used when it is
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* known that no threads are concurrently updating.
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*/
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public void reset() {
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internalReset(0L);
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}
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/**
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* Equivalent in effect to {@link #sum} followed by {@link
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* #reset}. This method may apply for example during quiescent
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* points between multithreaded computations. If there are
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* updates concurrent with this method, the returned value is
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* <em>not</em> guaranteed to be the final value occurring before
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* the reset.
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*
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* @return the sum
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*/
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public long sumThenReset() {
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long sum = base;
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Cell[] as = cells;
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base = 0L;
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if (as != null) {
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int n = as.length;
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for (int i = 0; i < n; ++i) {
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Cell a = as[i];
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if (a != null) {
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sum += a.value;
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a.value = 0L;
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}
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}
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}
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return sum;
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}
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/**
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* Returns the String representation of the {@link #sum}.
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* @return the String representation of the {@link #sum}
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*/
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public String toString() {
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return Long.toString(sum());
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}
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/**
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* Equivalent to {@link #sum}.
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*
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* @return the sum
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*/
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public long longValue() {
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return sum();
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}
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/**
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* Returns the {@link #sum} as an {@code int} after a narrowing
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* primitive conversion.
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*/
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public int intValue() {
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return (int)sum();
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}
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/**
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* Returns the {@link #sum} as a {@code float}
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* after a widening primitive conversion.
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*/
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public float floatValue() {
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return (float)sum();
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}
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/**
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* Returns the {@link #sum} as a {@code double} after a widening
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* primitive conversion.
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*/
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public double doubleValue() {
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return (double)sum();
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}
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private void writeObject(ObjectOutputStream s) throws IOException {
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s.defaultWriteObject();
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s.writeLong(sum());
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}
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private void readObject(ObjectInputStream s)
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throws IOException, ClassNotFoundException {
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s.defaultReadObject();
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busy = 0;
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cells = null;
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base = s.readLong();
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}
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}
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@ -1,349 +0,0 @@
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/**
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* Copyright 2016 Nikita Koksharov
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*
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* Licensed 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
|
||||
*
|
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* 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.
|
||||
*/
|
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|
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/*
|
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* Written by Doug Lea with assistance from members of JCP JSR-166
|
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* Expert Group and released to the public domain, as explained at
|
||||
* http://creativecommons.org/publicdomain/zero/1.0/
|
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*/
|
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package org.redisson.misc;
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import java.util.Random;
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/**
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* A package-local class holding common representation and mechanics
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* for classes supporting dynamic striping on 64bit values. The class
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* extends Number so that concrete subclasses must publicly do so.
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*/
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abstract class Striped64 extends Number {
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/*
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* This class maintains a lazily-initialized table of atomically
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* updated variables, plus an extra "base" field. The table size
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* is a power of two. Indexing uses masked per-thread hash codes.
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* Nearly all declarations in this class are package-private,
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* accessed directly by subclasses.
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*
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* Table entries are of class Cell; a variant of AtomicLong padded
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* to reduce cache contention on most processors. Padding is
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* overkill for most Atomics because they are usually irregularly
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* scattered in memory and thus don't interfere much with each
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* other. But Atomic objects residing in arrays will tend to be
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* placed adjacent to each other, and so will most often share
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* cache lines (with a huge negative performance impact) without
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* this precaution.
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*
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* In part because Cells are relatively large, we avoid creating
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* them until they are needed. When there is no contention, all
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* updates are made to the base field. Upon first contention (a
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* failed CAS on base update), the table is initialized to size 2.
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* The table size is doubled upon further contention until
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* reaching the nearest power of two greater than or equal to the
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* number of CPUS. Table slots remain empty (null) until they are
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* needed.
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*
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* A single spinlock ("busy") is used for initializing and
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* resizing the table, as well as populating slots with new Cells.
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* There is no need for a blocking lock; when the lock is not
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* available, threads try other slots (or the base). During these
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* retries, there is increased contention and reduced locality,
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* which is still better than alternatives.
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*
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* Per-thread hash codes are initialized to random values.
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* Contention and/or table collisions are indicated by failed
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* CASes when performing an update operation (see method
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* retryUpdate). Upon a collision, if the table size is less than
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* the capacity, it is doubled in size unless some other thread
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* holds the lock. If a hashed slot is empty, and lock is
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* available, a new Cell is created. Otherwise, if the slot
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* exists, a CAS is tried. Retries proceed by "double hashing",
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* using a secondary hash (Marsaglia XorShift) to try to find a
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* free slot.
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*
|
||||
* The table size is capped because, when there are more threads
|
||||
* than CPUs, supposing that each thread were bound to a CPU,
|
||||
* there would exist a perfect hash function mapping threads to
|
||||
* slots that eliminates collisions. When we reach capacity, we
|
||||
* search for this mapping by randomly varying the hash codes of
|
||||
* colliding threads. Because search is random, and collisions
|
||||
* only become known via CAS failures, convergence can be slow,
|
||||
* and because threads are typically not bound to CPUS forever,
|
||||
* may not occur at all. However, despite these limitations,
|
||||
* observed contention rates are typically low in these cases.
|
||||
*
|
||||
* It is possible for a Cell to become unused when threads that
|
||||
* once hashed to it terminate, as well as in the case where
|
||||
* doubling the table causes no thread to hash to it under
|
||||
* expanded mask. We do not try to detect or remove such cells,
|
||||
* under the assumption that for long-running instances, observed
|
||||
* contention levels will recur, so the cells will eventually be
|
||||
* needed again; and for short-lived ones, it does not matter.
|
||||
*/
|
||||
|
||||
/**
|
||||
* Padded variant of AtomicLong supporting only raw accesses plus CAS.
|
||||
* The value field is placed between pads, hoping that the JVM doesn't
|
||||
* reorder them.
|
||||
*
|
||||
* JVM intrinsics note: It would be possible to use a release-only
|
||||
* form of CAS here, if it were provided.
|
||||
*/
|
||||
static final class Cell {
|
||||
volatile long p0, p1, p2, p3, p4, p5, p6;
|
||||
volatile long value;
|
||||
volatile long q0, q1, q2, q3, q4, q5, q6;
|
||||
Cell(long x) { value = x; }
|
||||
|
||||
final boolean cas(long cmp, long val) {
|
||||
return UNSAFE.compareAndSwapLong(this, valueOffset, cmp, val);
|
||||
}
|
||||
|
||||
// Unsafe mechanics
|
||||
private static final sun.misc.Unsafe UNSAFE;
|
||||
private static final long valueOffset;
|
||||
static {
|
||||
try {
|
||||
UNSAFE = getUnsafe();
|
||||
Class<?> ak = Cell.class;
|
||||
valueOffset = UNSAFE.objectFieldOffset
|
||||
(ak.getDeclaredField("value"));
|
||||
} catch (Exception e) {
|
||||
throw new Error(e);
|
||||
}
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
/**
|
||||
* ThreadLocal holding a single-slot int array holding hash code.
|
||||
* Unlike the JDK8 version of this class, we use a suboptimal
|
||||
* int[] representation to avoid introducing a new type that can
|
||||
* impede class-unloading when ThreadLocals are not removed.
|
||||
*/
|
||||
static final ThreadLocal<int[]> threadHashCode = new ThreadLocal<int[]>();
|
||||
|
||||
/**
|
||||
* Generator of new random hash codes
|
||||
*/
|
||||
static final Random rng = new Random();
|
||||
|
||||
/** Number of CPUS, to place bound on table size */
|
||||
static final int NCPU = Runtime.getRuntime().availableProcessors();
|
||||
|
||||
/**
|
||||
* Table of cells. When non-null, size is a power of 2.
|
||||
*/
|
||||
transient volatile Cell[] cells;
|
||||
|
||||
/**
|
||||
* Base value, used mainly when there is no contention, but also as
|
||||
* a fallback during table initialization races. Updated via CAS.
|
||||
*/
|
||||
transient volatile long base;
|
||||
|
||||
/**
|
||||
* Spinlock (locked via CAS) used when resizing and/or creating Cells.
|
||||
*/
|
||||
transient volatile int busy;
|
||||
|
||||
/**
|
||||
* Package-private default constructor
|
||||
*/
|
||||
Striped64() {
|
||||
}
|
||||
|
||||
/**
|
||||
* CASes the base field.
|
||||
*/
|
||||
final boolean casBase(long cmp, long val) {
|
||||
return UNSAFE.compareAndSwapLong(this, baseOffset, cmp, val);
|
||||
}
|
||||
|
||||
/**
|
||||
* CASes the busy field from 0 to 1 to acquire lock.
|
||||
*/
|
||||
final boolean casBusy() {
|
||||
return UNSAFE.compareAndSwapInt(this, busyOffset, 0, 1);
|
||||
}
|
||||
|
||||
/**
|
||||
* Computes the function of current and new value. Subclasses
|
||||
* should open-code this update function for most uses, but the
|
||||
* virtualized form is needed within retryUpdate.
|
||||
*
|
||||
* @param currentValue the current value (of either base or a cell)
|
||||
* @param newValue the argument from a user update call
|
||||
* @return result of the update function
|
||||
*/
|
||||
abstract long fn(long currentValue, long newValue);
|
||||
|
||||
/**
|
||||
* Handles cases of updates involving initialization, resizing,
|
||||
* creating new Cells, and/or contention. See above for
|
||||
* explanation. This method suffers the usual non-modularity
|
||||
* problems of optimistic retry code, relying on rechecked sets of
|
||||
* reads.
|
||||
*
|
||||
* @param x the value
|
||||
* @param hc the hash code holder
|
||||
* @param wasUncontended false if CAS failed before call
|
||||
*/
|
||||
final void retryUpdate(long x, int[] hc, boolean wasUncontended) {
|
||||
int h;
|
||||
if (hc == null) {
|
||||
threadHashCode.set(hc = new int[1]); // Initialize randomly
|
||||
int r = rng.nextInt(); // Avoid zero to allow xorShift rehash
|
||||
h = hc[0] = (r == 0) ? 1 : r;
|
||||
}
|
||||
else
|
||||
h = hc[0];
|
||||
boolean collide = false; // True if last slot nonempty
|
||||
for (;;) {
|
||||
Cell[] as; Cell a; int n; long v;
|
||||
if ((as = cells) != null && (n = as.length) > 0) {
|
||||
if ((a = as[(n - 1) & h]) == null) {
|
||||
if (busy == 0) { // Try to attach new Cell
|
||||
Cell r = new Cell(x); // Optimistically create
|
||||
if (busy == 0 && casBusy()) {
|
||||
boolean created = false;
|
||||
try { // Recheck under lock
|
||||
Cell[] rs; int m, j;
|
||||
if ((rs = cells) != null &&
|
||||
(m = rs.length) > 0 &&
|
||||
rs[j = (m - 1) & h] == null) {
|
||||
rs[j] = r;
|
||||
created = true;
|
||||
}
|
||||
} finally {
|
||||
busy = 0;
|
||||
}
|
||||
if (created)
|
||||
break;
|
||||
continue; // Slot is now non-empty
|
||||
}
|
||||
}
|
||||
collide = false;
|
||||
}
|
||||
else if (!wasUncontended) // CAS already known to fail
|
||||
wasUncontended = true; // Continue after rehash
|
||||
else if (a.cas(v = a.value, fn(v, x)))
|
||||
break;
|
||||
else if (n >= NCPU || cells != as)
|
||||
collide = false; // At max size or stale
|
||||
else if (!collide)
|
||||
collide = true;
|
||||
else if (busy == 0 && casBusy()) {
|
||||
try {
|
||||
if (cells == as) { // Expand table unless stale
|
||||
Cell[] rs = new Cell[n << 1];
|
||||
for (int i = 0; i < n; ++i)
|
||||
rs[i] = as[i];
|
||||
cells = rs;
|
||||
}
|
||||
} finally {
|
||||
busy = 0;
|
||||
}
|
||||
collide = false;
|
||||
continue; // Retry with expanded table
|
||||
}
|
||||
h ^= h << 13; // Rehash
|
||||
h ^= h >>> 17;
|
||||
h ^= h << 5;
|
||||
hc[0] = h; // Record index for next time
|
||||
}
|
||||
else if (busy == 0 && cells == as && casBusy()) {
|
||||
boolean init = false;
|
||||
try { // Initialize table
|
||||
if (cells == as) {
|
||||
Cell[] rs = new Cell[2];
|
||||
rs[h & 1] = new Cell(x);
|
||||
cells = rs;
|
||||
init = true;
|
||||
}
|
||||
} finally {
|
||||
busy = 0;
|
||||
}
|
||||
if (init)
|
||||
break;
|
||||
}
|
||||
else if (casBase(v = base, fn(v, x)))
|
||||
break; // Fall back on using base
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
/**
|
||||
* Sets base and all cells to the given value.
|
||||
*/
|
||||
final void internalReset(long initialValue) {
|
||||
Cell[] as = cells;
|
||||
base = initialValue;
|
||||
if (as != null) {
|
||||
int n = as.length;
|
||||
for (int i = 0; i < n; ++i) {
|
||||
Cell a = as[i];
|
||||
if (a != null)
|
||||
a.value = initialValue;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// Unsafe mechanics
|
||||
private static final sun.misc.Unsafe UNSAFE;
|
||||
private static final long baseOffset;
|
||||
private static final long busyOffset;
|
||||
static {
|
||||
try {
|
||||
UNSAFE = getUnsafe();
|
||||
Class<?> sk = Striped64.class;
|
||||
baseOffset = UNSAFE.objectFieldOffset
|
||||
(sk.getDeclaredField("base"));
|
||||
busyOffset = UNSAFE.objectFieldOffset
|
||||
(sk.getDeclaredField("busy"));
|
||||
} catch (Exception e) {
|
||||
throw new Error(e);
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Returns a sun.misc.Unsafe. Suitable for use in a 3rd party package.
|
||||
* Replace with a simple call to Unsafe.getUnsafe when integrating
|
||||
* into a jdk.
|
||||
*
|
||||
* @return a sun.misc.Unsafe
|
||||
*/
|
||||
private static sun.misc.Unsafe getUnsafe() {
|
||||
try {
|
||||
return sun.misc.Unsafe.getUnsafe();
|
||||
} catch (SecurityException tryReflectionInstead) {}
|
||||
try {
|
||||
return java.security.AccessController.doPrivileged
|
||||
(new java.security.PrivilegedExceptionAction<sun.misc.Unsafe>() {
|
||||
public sun.misc.Unsafe run() throws Exception {
|
||||
Class<sun.misc.Unsafe> k = sun.misc.Unsafe.class;
|
||||
for (java.lang.reflect.Field f : k.getDeclaredFields()) {
|
||||
f.setAccessible(true);
|
||||
Object x = f.get(null);
|
||||
if (k.isInstance(x))
|
||||
return k.cast(x);
|
||||
}
|
||||
throw new NoSuchFieldError("the Unsafe");
|
||||
}});
|
||||
} catch (java.security.PrivilegedActionException e) {
|
||||
throw new RuntimeException("Could not initialize intrinsics",
|
||||
e.getCause());
|
||||
}
|
||||
}
|
||||
}
|
Loading…
Reference in New Issue