org.neo4j.driver.internal.shaded.io.netty.util.internal.shaded.org.jctools.queues.atomic.BaseLinkedAtomicQueue Maven / Gradle / Ivy
/*
* 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
*
* 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 io.netty.util.internal.shaded.org.jctools.queues.atomic;
import java.util.AbstractQueue;
import java.util.Iterator;
import java.util.Queue;
import java.util.concurrent.atomic.AtomicReferenceFieldUpdater;
import java.util.concurrent.atomic.AtomicLongFieldUpdater;
import java.util.concurrent.atomic.AtomicReferenceArray;
import io.netty.util.internal.shaded.org.jctools.queues.MessagePassingQueue;
import io.netty.util.internal.shaded.org.jctools.queues.MessagePassingQueue.Supplier;
import io.netty.util.internal.shaded.org.jctools.queues.MessagePassingQueueUtil;
import io.netty.util.internal.shaded.org.jctools.queues.QueueProgressIndicators;
import io.netty.util.internal.shaded.org.jctools.queues.IndexedQueueSizeUtil;
import static io.netty.util.internal.shaded.org.jctools.queues.atomic.AtomicQueueUtil.*;
/**
* NOTE: This class was automatically generated by io.netty.util.internal.shaded.org.jctools.queues.atomic.JavaParsingAtomicLinkedQueueGenerator
* which can found in the jctools-build module. The original source file is BaseLinkedQueue.java.
*/
abstract class BaseLinkedAtomicQueuePad0 extends AbstractQueue implements MessagePassingQueue {
// 8b
byte b000, b001, b002, b003, b004, b005, b006, b007;
// 16b
byte b010, b011, b012, b013, b014, b015, b016, b017;
// 24b
byte b020, b021, b022, b023, b024, b025, b026, b027;
// 32b
byte b030, b031, b032, b033, b034, b035, b036, b037;
// 40b
byte b040, b041, b042, b043, b044, b045, b046, b047;
// 48b
byte b050, b051, b052, b053, b054, b055, b056, b057;
// 56b
byte b060, b061, b062, b063, b064, b065, b066, b067;
// 64b
byte b070, b071, b072, b073, b074, b075, b076, b077;
// 72b
byte b100, b101, b102, b103, b104, b105, b106, b107;
// 80b
byte b110, b111, b112, b113, b114, b115, b116, b117;
// 88b
byte b120, b121, b122, b123, b124, b125, b126, b127;
// 96b
byte b130, b131, b132, b133, b134, b135, b136, b137;
// 104b
byte b140, b141, b142, b143, b144, b145, b146, b147;
// 112b
byte b150, b151, b152, b153, b154, b155, b156, b157;
// 120b
byte b160, b161, b162, b163, b164, b165, b166, b167;
}
/**
* NOTE: This class was automatically generated by io.netty.util.internal.shaded.org.jctools.queues.atomic.JavaParsingAtomicLinkedQueueGenerator
* which can found in the jctools-build module. The original source file is BaseLinkedQueue.java.
*/
abstract class BaseLinkedAtomicQueueProducerNodeRef extends BaseLinkedAtomicQueuePad0 {
private static final AtomicReferenceFieldUpdater P_NODE_UPDATER = AtomicReferenceFieldUpdater.newUpdater(BaseLinkedAtomicQueueProducerNodeRef.class, LinkedQueueAtomicNode.class, "producerNode");
private volatile LinkedQueueAtomicNode producerNode;
final void spProducerNode(LinkedQueueAtomicNode newValue) {
P_NODE_UPDATER.lazySet(this, newValue);
}
final void soProducerNode(LinkedQueueAtomicNode newValue) {
P_NODE_UPDATER.lazySet(this, newValue);
}
final LinkedQueueAtomicNode lvProducerNode() {
return producerNode;
}
final boolean casProducerNode(LinkedQueueAtomicNode expect, LinkedQueueAtomicNode newValue) {
return P_NODE_UPDATER.compareAndSet(this, expect, newValue);
}
final LinkedQueueAtomicNode lpProducerNode() {
return producerNode;
}
protected final LinkedQueueAtomicNode xchgProducerNode(LinkedQueueAtomicNode newValue) {
return P_NODE_UPDATER.getAndSet(this, newValue);
}
}
/**
* NOTE: This class was automatically generated by io.netty.util.internal.shaded.org.jctools.queues.atomic.JavaParsingAtomicLinkedQueueGenerator
* which can found in the jctools-build module. The original source file is BaseLinkedQueue.java.
*/
abstract class BaseLinkedAtomicQueuePad1 extends BaseLinkedAtomicQueueProducerNodeRef {
// 8b
byte b000, b001, b002, b003, b004, b005, b006, b007;
// 16b
byte b010, b011, b012, b013, b014, b015, b016, b017;
// 24b
byte b020, b021, b022, b023, b024, b025, b026, b027;
// 32b
byte b030, b031, b032, b033, b034, b035, b036, b037;
// 40b
byte b040, b041, b042, b043, b044, b045, b046, b047;
// 48b
byte b050, b051, b052, b053, b054, b055, b056, b057;
// 56b
byte b060, b061, b062, b063, b064, b065, b066, b067;
// 64b
byte b070, b071, b072, b073, b074, b075, b076, b077;
// 72b
byte b100, b101, b102, b103, b104, b105, b106, b107;
// 80b
byte b110, b111, b112, b113, b114, b115, b116, b117;
// 88b
byte b120, b121, b122, b123, b124, b125, b126, b127;
// 96b
byte b130, b131, b132, b133, b134, b135, b136, b137;
// 104b
byte b140, b141, b142, b143, b144, b145, b146, b147;
// 112b
byte b150, b151, b152, b153, b154, b155, b156, b157;
// 120b
byte b160, b161, b162, b163, b164, b165, b166, b167;
// 128b
byte b170, b171, b172, b173, b174, b175, b176, b177;
}
/**
* NOTE: This class was automatically generated by io.netty.util.internal.shaded.org.jctools.queues.atomic.JavaParsingAtomicLinkedQueueGenerator
* which can found in the jctools-build module. The original source file is BaseLinkedQueue.java.
*/
abstract class BaseLinkedAtomicQueueConsumerNodeRef extends BaseLinkedAtomicQueuePad1 {
private static final AtomicReferenceFieldUpdater C_NODE_UPDATER = AtomicReferenceFieldUpdater.newUpdater(BaseLinkedAtomicQueueConsumerNodeRef.class, LinkedQueueAtomicNode.class, "consumerNode");
private volatile LinkedQueueAtomicNode consumerNode;
final void spConsumerNode(LinkedQueueAtomicNode newValue) {
C_NODE_UPDATER.lazySet(this, newValue);
}
@SuppressWarnings("unchecked")
final LinkedQueueAtomicNode lvConsumerNode() {
return consumerNode;
}
final LinkedQueueAtomicNode lpConsumerNode() {
return consumerNode;
}
}
/**
* NOTE: This class was automatically generated by io.netty.util.internal.shaded.org.jctools.queues.atomic.JavaParsingAtomicLinkedQueueGenerator
* which can found in the jctools-build module. The original source file is BaseLinkedQueue.java.
*/
abstract class BaseLinkedAtomicQueuePad2 extends BaseLinkedAtomicQueueConsumerNodeRef {
// 8b
byte b000, b001, b002, b003, b004, b005, b006, b007;
// 16b
byte b010, b011, b012, b013, b014, b015, b016, b017;
// 24b
byte b020, b021, b022, b023, b024, b025, b026, b027;
// 32b
byte b030, b031, b032, b033, b034, b035, b036, b037;
// 40b
byte b040, b041, b042, b043, b044, b045, b046, b047;
// 48b
byte b050, b051, b052, b053, b054, b055, b056, b057;
// 56b
byte b060, b061, b062, b063, b064, b065, b066, b067;
// 64b
byte b070, b071, b072, b073, b074, b075, b076, b077;
// 72b
byte b100, b101, b102, b103, b104, b105, b106, b107;
// 80b
byte b110, b111, b112, b113, b114, b115, b116, b117;
// 88b
byte b120, b121, b122, b123, b124, b125, b126, b127;
// 96b
byte b130, b131, b132, b133, b134, b135, b136, b137;
// 104b
byte b140, b141, b142, b143, b144, b145, b146, b147;
// 112b
byte b150, b151, b152, b153, b154, b155, b156, b157;
// 120b
byte b160, b161, b162, b163, b164, b165, b166, b167;
// 128b
byte b170, b171, b172, b173, b174, b175, b176, b177;
}
/**
* NOTE: This class was automatically generated by io.netty.util.internal.shaded.org.jctools.queues.atomic.JavaParsingAtomicLinkedQueueGenerator
* which can found in the jctools-build module. The original source file is BaseLinkedQueue.java.
*
* A base data structure for concurrent linked queues. For convenience also pulled in common single consumer
* methods since at this time there's no plan to implement MC.
*/
abstract class BaseLinkedAtomicQueue extends BaseLinkedAtomicQueuePad2 {
@Override
public final Iterator iterator() {
throw new UnsupportedOperationException();
}
@Override
public String toString() {
return this.getClass().getName();
}
protected final LinkedQueueAtomicNode newNode() {
return new LinkedQueueAtomicNode();
}
protected final LinkedQueueAtomicNode newNode(E e) {
return new LinkedQueueAtomicNode(e);
}
/**
* {@inheritDoc}
*
* IMPLEMENTATION NOTES:
* This is an O(n) operation as we run through all the nodes and count them.
* The accuracy of the value returned by this method is subject to races with producer/consumer threads. In
* particular when racing with the consumer thread this method may under estimate the size.
*
* @see java.util.Queue#size()
*/
@Override
public final int size() {
// Read consumer first, this is important because if the producer is node is 'older' than the consumer
// the consumer may overtake it (consume past it) invalidating the 'snapshot' notion of size.
LinkedQueueAtomicNode chaserNode = lvConsumerNode();
LinkedQueueAtomicNode producerNode = lvProducerNode();
int size = 0;
// must chase the nodes all the way to the producer node, but there's no need to count beyond expected head.
while (// don't go passed producer node
chaserNode != producerNode && // stop at last node
chaserNode != null && // stop at max int
size < Integer.MAX_VALUE) {
LinkedQueueAtomicNode next;
next = chaserNode.lvNext();
// check if this node has been consumed, if so return what we have
if (next == chaserNode) {
return size;
}
chaserNode = next;
size++;
}
return size;
}
/**
* {@inheritDoc}
*
* IMPLEMENTATION NOTES:
* Queue is empty when producerNode is the same as consumerNode. An alternative implementation would be to
* observe the producerNode.value is null, which also means an empty queue because only the
* consumerNode.value is allowed to be null.
*
* @see MessagePassingQueue#isEmpty()
*/
@Override
public boolean isEmpty() {
LinkedQueueAtomicNode consumerNode = lvConsumerNode();
LinkedQueueAtomicNode producerNode = lvProducerNode();
return consumerNode == producerNode;
}
protected E getSingleConsumerNodeValue(LinkedQueueAtomicNode currConsumerNode, LinkedQueueAtomicNode nextNode) {
// we have to null out the value because we are going to hang on to the node
final E nextValue = nextNode.getAndNullValue();
// Fix up the next ref of currConsumerNode to prevent promoted nodes from keeping new ones alive.
// We use a reference to self instead of null because null is already a meaningful value (the next of
// producer node is null).
currConsumerNode.soNext(currConsumerNode);
spConsumerNode(nextNode);
// currConsumerNode is now no longer referenced and can be collected
return nextValue;
}
/**
* {@inheritDoc}
*
* IMPLEMENTATION NOTES:
* Poll is allowed from a SINGLE thread.
* Poll is potentially blocking here as the {@link Queue#poll()} does not allow returning {@code null} if the queue is not
* empty. This is very different from the original Vyukov guarantees. See {@link #relaxedPoll()} for the original
* semantics.
* Poll reads {@code consumerNode.next} and:
*
* - If it is {@code null} AND the queue is empty return {@code null}, if queue is not empty spin wait for
* value to become visible.
*
- If it is not {@code null} set it as the consumer node and return it's now evacuated value.
*
* This means the consumerNode.value is always {@code null}, which is also the starting point for the queue.
* Because {@code null} values are not allowed to be offered this is the only node with it's value set to
* {@code null} at any one time.
*
* @see MessagePassingQueue#poll()
* @see java.util.Queue#poll()
*/
@Override
public E poll() {
final LinkedQueueAtomicNode currConsumerNode = lpConsumerNode();
LinkedQueueAtomicNode nextNode = currConsumerNode.lvNext();
if (nextNode != null) {
return getSingleConsumerNodeValue(currConsumerNode, nextNode);
} else if (currConsumerNode != lvProducerNode()) {
nextNode = spinWaitForNextNode(currConsumerNode);
// got the next node...
return getSingleConsumerNodeValue(currConsumerNode, nextNode);
}
return null;
}
/**
* {@inheritDoc}
*
* IMPLEMENTATION NOTES:
* Peek is allowed from a SINGLE thread.
* Peek is potentially blocking here as the {@link Queue#peek()} does not allow returning {@code null} if the queue is not
* empty. This is very different from the original Vyukov guarantees. See {@link #relaxedPeek()} for the original
* semantics.
* Poll reads the next node from the consumerNode and:
*
* - If it is {@code null} AND the queue is empty return {@code null}, if queue is not empty spin wait for
* value to become visible.
*
- If it is not {@code null} return it's value.
*
*
* @see MessagePassingQueue#peek()
* @see java.util.Queue#peek()
*/
@Override
public E peek() {
final LinkedQueueAtomicNode currConsumerNode = lpConsumerNode();
LinkedQueueAtomicNode nextNode = currConsumerNode.lvNext();
if (nextNode != null) {
return nextNode.lpValue();
} else if (currConsumerNode != lvProducerNode()) {
nextNode = spinWaitForNextNode(currConsumerNode);
// got the next node...
return nextNode.lpValue();
}
return null;
}
LinkedQueueAtomicNode spinWaitForNextNode(LinkedQueueAtomicNode currNode) {
LinkedQueueAtomicNode nextNode;
while ((nextNode = currNode.lvNext()) == null) {
// spin, we are no longer wait free
}
return nextNode;
}
@Override
public E relaxedPoll() {
final LinkedQueueAtomicNode currConsumerNode = lpConsumerNode();
final LinkedQueueAtomicNode nextNode = currConsumerNode.lvNext();
if (nextNode != null) {
return getSingleConsumerNodeValue(currConsumerNode, nextNode);
}
return null;
}
@Override
public E relaxedPeek() {
final LinkedQueueAtomicNode nextNode = lpConsumerNode().lvNext();
if (nextNode != null) {
return nextNode.lpValue();
}
return null;
}
@Override
public boolean relaxedOffer(E e) {
return offer(e);
}
@Override
public int drain(Consumer c, int limit) {
if (null == c)
throw new IllegalArgumentException("c is null");
if (limit < 0)
throw new IllegalArgumentException("limit is negative: " + limit);
if (limit == 0)
return 0;
LinkedQueueAtomicNode chaserNode = this.lpConsumerNode();
for (int i = 0; i < limit; i++) {
final LinkedQueueAtomicNode nextNode = chaserNode.lvNext();
if (nextNode == null) {
return i;
}
// we have to null out the value because we are going to hang on to the node
final E nextValue = getSingleConsumerNodeValue(chaserNode, nextNode);
chaserNode = nextNode;
c.accept(nextValue);
}
return limit;
}
@Override
public int drain(Consumer c) {
return MessagePassingQueueUtil.drain(this, c);
}
@Override
public void drain(Consumer c, WaitStrategy wait, ExitCondition exit) {
MessagePassingQueueUtil.drain(this, c, wait, exit);
}
@Override
public int capacity() {
return UNBOUNDED_CAPACITY;
}
}