X-Git-Url: https://git.opendaylight.org/gerrit/gitweb?p=controller.git;a=blobdiff_plain;f=opendaylight%2Fmd-sal%2Fsal-distributed-datastore%2Fsrc%2Fmain%2Fjava%2Forg%2Fopendaylight%2Fcontroller%2Fcluster%2Fdatastore%2FTransactionChainProxy.java;h=0946b402fd9bb02b3129d48d5f5236ea605510a5;hp=93f9e6b7de1e2085f01d36c74a37b84ff7ecb4d2;hb=86e398bb1e1a60f7516b398a0f27268bf232049d;hpb=f91539efb39f81d5db8cd15331d66b7589b745a8 diff --git a/opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/TransactionChainProxy.java b/opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/TransactionChainProxy.java index 93f9e6b7de..0946b402fd 100644 --- a/opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/TransactionChainProxy.java +++ b/opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/TransactionChainProxy.java @@ -1,120 +1,262 @@ /* - * Copyright (c) 2014 Cisco Systems, Inc. and others. All rights reserved. + * Copyright (c) 2015 Cisco Systems, Inc. and others. All rights reserved. * * This program and the accompanying materials are made available under the * terms of the Eclipse Public License v1.0 which accompanies this distribution, * and is available at http://www.eclipse.org/legal/epl-v10.html */ - package org.opendaylight.controller.cluster.datastore; import akka.actor.ActorSelection; import akka.dispatch.OnComplete; -import java.util.AbstractMap.SimpleEntry; -import java.util.List; +import com.google.common.base.Preconditions; +import java.util.Collection; +import java.util.concurrent.atomic.AtomicInteger; +import java.util.concurrent.atomic.AtomicReferenceFieldUpdater; +import org.opendaylight.controller.cluster.datastore.identifiers.TransactionChainIdentifier; +import org.opendaylight.controller.cluster.datastore.identifiers.TransactionIdentifier; import org.opendaylight.controller.cluster.datastore.messages.CloseTransactionChain; -import org.opendaylight.controller.cluster.datastore.utils.ActorContext; +import org.opendaylight.controller.cluster.datastore.messages.PrimaryShardInfo; +import org.opendaylight.controller.md.sal.common.api.data.TransactionChainClosedException; import org.opendaylight.controller.sal.core.spi.data.DOMStoreReadTransaction; import org.opendaylight.controller.sal.core.spi.data.DOMStoreReadWriteTransaction; import org.opendaylight.controller.sal.core.spi.data.DOMStoreTransactionChain; import org.opendaylight.controller.sal.core.spi.data.DOMStoreWriteTransaction; +import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTree; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; import scala.concurrent.Future; import scala.concurrent.Promise; /** - * TransactionChainProxy acts as a proxy for a DOMStoreTransactionChain created on a remote shard + * A chain of {@link TransactionProxy}s. It allows a single open transaction to be open + * at a time. For remote transactions, it also tracks the outstanding readiness requests + * towards the shard and unblocks operations only after all have completed. */ -public class TransactionChainProxy implements DOMStoreTransactionChain{ - private final ActorContext actorContext; - private final String transactionChainId; - private volatile SimpleEntry>> previousTxReadyFutures; +final class TransactionChainProxy extends AbstractTransactionContextFactory implements DOMStoreTransactionChain { + private static abstract class State { + /** + * Check if it is okay to allocate a new transaction. + * @throws IllegalStateException if a transaction may not be allocated. + */ + abstract void checkReady(); + + /** + * Return the future which needs to be waited for before shard information + * is returned (which unblocks remote transactions). + * @return Future to wait for, or null of no wait is necessary + */ + abstract Future previousFuture(); + } + + private static abstract class Pending extends State { + private final TransactionIdentifier transaction; + private final Future previousFuture; + + Pending(final TransactionIdentifier transaction, final Future previousFuture) { + this.previousFuture = previousFuture; + this.transaction = Preconditions.checkNotNull(transaction); + } + + @Override + final Future previousFuture() { + return previousFuture; + } + + final TransactionIdentifier getIdentifier() { + return transaction; + } + } + + private static final class Allocated extends Pending { + Allocated(final TransactionIdentifier transaction, final Future previousFuture) { + super(transaction, previousFuture); + } + + @Override + void checkReady() { + throw new IllegalStateException(String.format("Previous transaction %s is not ready yet", getIdentifier())); + } + } + + private static final class Submitted extends Pending { + Submitted(final TransactionIdentifier transaction, final Future previousFuture) { + super(transaction, previousFuture); + } + + @Override + void checkReady() { + // Okay to allocate + } + } + + private static abstract class DefaultState extends State { + @Override + final Future previousFuture() { + return null; + } + } + + private static final State IDLE_STATE = new DefaultState() { + @Override + void checkReady() { + // Okay to allocate + } + }; - public TransactionChainProxy(ActorContext actorContext) { - this.actorContext = actorContext; - transactionChainId = actorContext.getCurrentMemberName() + "-" + System.currentTimeMillis(); + private static final State CLOSED_STATE = new DefaultState() { + @Override + void checkReady() { + throw new TransactionChainClosedException("Transaction chain has been closed"); + } + }; + + private static final Logger LOG = LoggerFactory.getLogger(TransactionChainProxy.class); + private static final AtomicInteger CHAIN_COUNTER = new AtomicInteger(); + private static final AtomicReferenceFieldUpdater STATE_UPDATER = + AtomicReferenceFieldUpdater.newUpdater(TransactionChainProxy.class, State.class, "currentState"); + + private final TransactionChainIdentifier transactionChainId; + private final TransactionContextFactory parent; + private volatile State currentState = IDLE_STATE; + + TransactionChainProxy(final TransactionContextFactory parent) { + super(parent.getActorContext()); + + transactionChainId = new TransactionChainIdentifier(parent.getActorContext().getCurrentMemberName(), CHAIN_COUNTER.incrementAndGet()); + this.parent = parent; + } + + public String getTransactionChainId() { + return transactionChainId.toString(); } @Override public DOMStoreReadTransaction newReadOnlyTransaction() { - return new ChainedTransactionProxy(actorContext, TransactionProxy.TransactionType.READ_ONLY); + currentState.checkReady(); + return new TransactionProxy(this, TransactionType.READ_ONLY); } @Override public DOMStoreReadWriteTransaction newReadWriteTransaction() { - return new ChainedTransactionProxy(actorContext, TransactionProxy.TransactionType.READ_WRITE); + getActorContext().acquireTxCreationPermit(); + return allocateWriteTransaction(TransactionType.READ_WRITE); } @Override public DOMStoreWriteTransaction newWriteOnlyTransaction() { - return new ChainedTransactionProxy(actorContext, TransactionProxy.TransactionType.WRITE_ONLY); + getActorContext().acquireTxCreationPermit(); + return allocateWriteTransaction(TransactionType.WRITE_ONLY); } @Override public void close() { + currentState = CLOSED_STATE; + // Send a close transaction chain request to each and every shard - actorContext.broadcast(new CloseTransactionChain(transactionChainId)); + getActorContext().broadcast(new CloseTransactionChain(transactionChainId.toString()).toSerializable()); } - public String getTransactionChainId() { - return transactionChainId; + private TransactionProxy allocateWriteTransaction(final TransactionType type) { + State localState = currentState; + localState.checkReady(); + + final TransactionProxy ret = new TransactionProxy(this, type); + currentState = new Allocated(ret.getIdentifier(), localState.previousFuture()); + return ret; } - private class ChainedTransactionProxy extends TransactionProxy { + @Override + protected LocalTransactionChain factoryForShard(final String shardName, final ActorSelection shardLeader, final DataTree dataTree) { + final LocalTransactionChain ret = new LocalTransactionChain(this, shardLeader, dataTree); + LOG.debug("Allocated transaction chain {} for shard {} leader {}", ret, shardName, shardLeader); + return ret; + } - ChainedTransactionProxy(ActorContext actorContext, TransactionType transactionType) { - super(actorContext, transactionType, transactionChainId); + /** + * This method is overridden to ensure the previous Tx's ready operations complete + * before we initiate the next Tx in the chain to avoid creation failures if the + * previous Tx's ready operations haven't completed yet. + */ + @Override + protected Future findPrimaryShard(final String shardName) { + // Read current state atomically + final State localState = currentState; + + // There are no outstanding futures, shortcut + final Future previous = localState.previousFuture(); + if (previous == null) { + return parent.findPrimaryShard(shardName); } - @Override - protected void onTransactionReady(List> cohortFutures) { - if(!cohortFutures.isEmpty()) { - previousTxReadyFutures = new SimpleEntry<>(getIdentifier(), cohortFutures); - } else { - previousTxReadyFutures = null; - } + final String previousTransactionId; + + if(localState instanceof Pending){ + previousTransactionId = ((Pending) localState).getIdentifier().toString(); + LOG.debug("Waiting for ready futures with pending Tx {}", previousTransactionId); + } else { + previousTransactionId = ""; + LOG.debug("Waiting for ready futures on chain {}", getTransactionChainId()); } - /** - * This method is overridden to ensure the previous Tx's ready operations complete - * before we create the next shard Tx in the chain to avoid creation failures if the - * previous Tx's ready operations haven't completed yet. - */ - @Override - protected Future sendCreateTransaction(final ActorSelection shard, - final Object serializedCreateMessage) { - // Check if there are any previous ready Futures. Also make sure the previous ready - // Futures aren't for this Tx as deadlock would occur if tried to wait on our own - // Futures. This may happen b/c the shard Tx creates are done async so it's possible - // for the client to ready this Tx before we've even attempted to create a shard Tx. - if(previousTxReadyFutures == null || - previousTxReadyFutures.getKey().equals(getIdentifier())) { - return super.sendCreateTransaction(shard, serializedCreateMessage); - } + // Add a callback for completion of the combined Futures. + final Promise returnPromise = akka.dispatch.Futures.promise(); - // Combine the ready Futures into 1. - Future> combinedFutures = akka.dispatch.Futures.sequence( - previousTxReadyFutures.getValue(), actorContext.getActorSystem().dispatcher()); - - // Add a callback for completion of the combined Futures. - final Promise createTxPromise = akka.dispatch.Futures.promise(); - OnComplete> onComplete = new OnComplete>() { - @Override - public void onComplete(Throwable failure, Iterable notUsed) { - if(failure != null) { - // A Ready Future failed so fail the returned Promise. - createTxPromise.failure(failure); - } else { - // Send the CreateTx message and use the resulting Future to complete the - // returned Promise. - createTxPromise.completeWith(actorContext.executeOperationAsync(shard, - serializedCreateMessage)); - } + final OnComplete onComplete = new OnComplete() { + @Override + public void onComplete(final Throwable failure, final Object notUsed) { + if (failure != null) { + // A Ready Future failed so fail the returned Promise. + LOG.error("Ready future failed for Tx {}", previousTransactionId); + returnPromise.failure(failure); + } else { + LOG.debug("Previous Tx {} readied - proceeding to FindPrimaryShard", + previousTransactionId); + + // Send the FindPrimaryShard message and use the resulting Future to complete the + // returned Promise. + returnPromise.completeWith(parent.findPrimaryShard(shardName)); } - }; + } + }; - combinedFutures.onComplete(onComplete, actorContext.getActorSystem().dispatcher()); + previous.onComplete(onComplete, getActorContext().getClientDispatcher()); + return returnPromise.future(); + } - return createTxPromise.future(); + @Override + protected void onTransactionReady(final TransactionIdentifier transaction, final Collection> cohortFutures) { + final State localState = currentState; + Preconditions.checkState(localState instanceof Allocated, "Readying transaction %s while state is %s", transaction, localState); + final TransactionIdentifier currentTx = ((Allocated)localState).getIdentifier(); + Preconditions.checkState(transaction.equals(currentTx), "Readying transaction %s while %s is allocated", transaction, currentTx); + + // Transaction ready and we are not waiting for futures -- go to idle + if (cohortFutures.isEmpty()) { + currentState = IDLE_STATE; + return; } + + // Combine the ready Futures into 1 + final Future> combined = akka.dispatch.Futures.sequence( + cohortFutures, getActorContext().getClientDispatcher()); + + // Record the we have outstanding futures + final State newState = new Submitted(transaction, combined); + currentState = newState; + + // Attach a completion reset, but only if we do not allocate a transaction + // in-between + combined.onComplete(new OnComplete>() { + @Override + public void onComplete(final Throwable arg0, final Iterable arg1) { + STATE_UPDATER.compareAndSet(TransactionChainProxy.this, newState, IDLE_STATE); + } + }, getActorContext().getClientDispatcher()); + } + + @Override + protected TransactionIdentifier nextIdentifier() { + return transactionChainId.newTransactionIdentifier(); } }