*/
package org.opendaylight.controller.cluster.datastore;
+import static com.google.common.base.Preconditions.checkState;
+import static java.util.Objects.requireNonNull;
+
import akka.actor.ActorSelection;
+import akka.dispatch.Futures;
import akka.dispatch.OnComplete;
-import com.google.common.base.Preconditions;
+import java.util.ArrayList;
import java.util.Collection;
-import java.util.concurrent.atomic.AtomicInteger;
+import java.util.List;
+import java.util.Map.Entry;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ConcurrentMap;
import java.util.concurrent.atomic.AtomicReferenceFieldUpdater;
-import org.opendaylight.controller.cluster.datastore.identifiers.TransactionIdentifier;
+import org.opendaylight.controller.cluster.access.concepts.LocalHistoryIdentifier;
+import org.opendaylight.controller.cluster.access.concepts.TransactionIdentifier;
import org.opendaylight.controller.cluster.datastore.messages.CloseTransactionChain;
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.opendaylight.mdsal.dom.api.DOMTransactionChainClosedException;
+import org.opendaylight.mdsal.dom.spi.store.DOMStoreReadTransaction;
+import org.opendaylight.mdsal.dom.spi.store.DOMStoreReadWriteTransaction;
+import org.opendaylight.mdsal.dom.spi.store.DOMStoreTransactionChain;
+import org.opendaylight.mdsal.dom.spi.store.DOMStoreWriteTransaction;
+import org.opendaylight.yangtools.yang.data.api.schema.tree.ReadOnlyDataTree;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import scala.concurrent.Future;
* at a time. For remote transactions, it also tracks the outstanding readiness requests
* towards the shard and unblocks operations only after all have completed.
*/
-final class TransactionChainProxy extends AbstractTransactionContextFactory<LocalTransactionChain> implements DOMStoreTransactionChain {
- private static abstract class State {
+final class TransactionChainProxy extends AbstractTransactionContextFactory<LocalTransactionChain>
+ implements DOMStoreTransactionChain {
+ private abstract static class State {
/**
* Check if it is okay to allocate a new transaction.
* @throws IllegalStateException if a transaction may not be allocated.
abstract Future<?> previousFuture();
}
- private static abstract class Pending extends State {
+ private abstract static 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);
+ this.transaction = requireNonNull(transaction);
}
@Override
}
}
- private static abstract class DefaultState extends State {
+ private abstract static class DefaultState extends State {
@Override
final Future<?> previousFuture() {
return null;
private static final State CLOSED_STATE = new DefaultState() {
@Override
void checkReady() {
- throw new TransactionChainClosedException("Transaction chain has been closed");
+ throw new DOMTransactionChainClosedException("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<TransactionChainProxy, State> STATE_UPDATER =
AtomicReferenceFieldUpdater.newUpdater(TransactionChainProxy.class, State.class, "currentState");
- private final String transactionChainId;
private final TransactionContextFactory parent;
private volatile State currentState = IDLE_STATE;
- TransactionChainProxy(final TransactionContextFactory parent) {
- super(parent.getActorContext());
- transactionChainId = parent.getActorContext().getCurrentMemberName() + "-txn-chain-" + CHAIN_COUNTER.incrementAndGet();
- this.parent = parent;
- }
+ /**
+ * This map holds Promise instances for each read-only tx. It is used to maintain ordering of tx creates
+ * wrt to read-only tx's between this class and a LocalTransactionChain since they're bridged by
+ * asynchronous futures. Otherwise, in the following scenario, eg:
+ * <p/>
+ * 1) Create write tx1 on chain
+ * 2) do write and submit
+ * 3) Create read-only tx2 on chain and issue read
+ * 4) Create write tx3 on chain, do write but do not submit
+ * <p/>
+ * if the sequence/timing is right, tx3 may create its local tx on the LocalTransactionChain before tx2,
+ * which results in tx2 failing b/c tx3 isn't ready yet. So maintaining ordering prevents this issue
+ * (see Bug 4774).
+ * <p/>
+ * A Promise is added via newReadOnlyTransaction. When the parent class completes the primary shard
+ * lookup and creates the TransactionContext (either success or failure), onTransactionContextCreated is
+ * called which completes the Promise. A write tx that is created prior to completion will wait on the
+ * Promise's Future via findPrimaryShard.
+ */
+ private final ConcurrentMap<TransactionIdentifier, Promise<Object>> priorReadOnlyTxPromises =
+ new ConcurrentHashMap<>();
- public String getTransactionChainId() {
- return transactionChainId;
+ TransactionChainProxy(final TransactionContextFactory parent, final LocalHistoryIdentifier historyId) {
+ super(parent.getActorUtils(), historyId);
+ this.parent = parent;
}
@Override
public DOMStoreReadTransaction newReadOnlyTransaction() {
currentState.checkReady();
- return new TransactionProxy(this, TransactionType.READ_ONLY);
+ TransactionProxy transactionProxy = new TransactionProxy(this, TransactionType.READ_ONLY);
+ priorReadOnlyTxPromises.put(transactionProxy.getIdentifier(), Futures.<Object>promise());
+ return transactionProxy;
}
@Override
public DOMStoreReadWriteTransaction newReadWriteTransaction() {
- getActorContext().acquireTxCreationPermit();
+ getActorUtils().acquireTxCreationPermit();
return allocateWriteTransaction(TransactionType.READ_WRITE);
}
@Override
public DOMStoreWriteTransaction newWriteOnlyTransaction() {
- getActorContext().acquireTxCreationPermit();
+ getActorUtils().acquireTxCreationPermit();
return allocateWriteTransaction(TransactionType.WRITE_ONLY);
}
currentState = CLOSED_STATE;
// Send a close transaction chain request to each and every shard
- getActorContext().broadcast(new CloseTransactionChain(transactionChainId).toSerializable());
+
+ getActorUtils().broadcast(version -> new CloseTransactionChain(getHistoryId(), version).toSerializable(),
+ CloseTransactionChain.class);
}
private TransactionProxy allocateWriteTransaction(final TransactionType type) {
}
@Override
- protected LocalTransactionChain factoryForShard(final String shardName, final ActorSelection shardLeader, final DataTree dataTree) {
+ protected LocalTransactionChain factoryForShard(final String shardName, final ActorSelection shardLeader,
+ final ReadOnlyDataTree dataTree) {
final LocalTransactionChain ret = new LocalTransactionChain(this, shardLeader, dataTree);
LOG.debug("Allocated transaction chain {} for shard {} leader {}", ret, shardName, shardLeader);
return ret;
* before we initiate the next Tx in the chain to avoid creation failures if the
* previous Tx's ready operations haven't completed yet.
*/
+ @SuppressWarnings({ "unchecked", "rawtypes" })
@Override
- protected Future<PrimaryShardInfo> findPrimaryShard(final String shardName) {
+ protected Future<PrimaryShardInfo> findPrimaryShard(final String shardName, final TransactionIdentifier txId) {
// Read current state atomically
final State localState = currentState;
// There are no outstanding futures, shortcut
- final Future<?> previous = localState.previousFuture();
+ Future<?> previous = localState.previousFuture();
if (previous == null) {
- return parent.findPrimaryShard(shardName);
+ return combineFutureWithPossiblePriorReadOnlyTxFutures(parent.findPrimaryShard(shardName, txId), txId);
}
- LOG.debug("Waiting for ready futures for on chain {}", getTransactionChainId());
+ final String previousTransactionId;
+
+ if (localState instanceof Pending) {
+ previousTransactionId = ((Pending) localState).getIdentifier().toString();
+ LOG.debug("Tx: {} - waiting for ready futures with pending Tx {}", txId, previousTransactionId);
+ } else {
+ previousTransactionId = "";
+ LOG.debug("Waiting for ready futures on chain {}", getHistoryId());
+ }
+
+ previous = combineFutureWithPossiblePriorReadOnlyTxFutures(previous, txId);
// Add a callback for completion of the combined Futures.
- final Promise<PrimaryShardInfo> returnPromise = akka.dispatch.Futures.promise();
+ final Promise<PrimaryShardInfo> returnPromise = Futures.promise();
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("Tx: {} - ready future failed for previous Tx {}", txId, previousTransactionId);
returnPromise.failure(failure);
} else {
- LOG.debug("Previous Tx readied - proceeding to FindPrimaryShard on chain {}",
- getTransactionChainId());
+ LOG.debug("Tx: {} - previous Tx {} readied - proceeding to FindPrimaryShard",
+ txId, previousTransactionId);
// Send the FindPrimaryShard message and use the resulting Future to complete the
// returned Promise.
- returnPromise.completeWith(parent.findPrimaryShard(shardName));
+ returnPromise.completeWith(parent.findPrimaryShard(shardName, txId));
}
}
};
- previous.onComplete(onComplete, getActorContext().getClientDispatcher());
+ previous.onComplete(onComplete, getActorUtils().getClientDispatcher());
+ return returnPromise.future();
+ }
+
+ private <T> Future<T> combineFutureWithPossiblePriorReadOnlyTxFutures(final Future<T> future,
+ final TransactionIdentifier txId) {
+ return priorReadOnlyTxPromises.isEmpty() || priorReadOnlyTxPromises.containsKey(txId) ? future
+ // Tough luck, we need do some work
+ : combineWithPriorReadOnlyTxFutures(future, txId);
+ }
+
+ // Split out of the common path
+ private <T> Future<T> combineWithPriorReadOnlyTxFutures(final Future<T> future, final TransactionIdentifier txId) {
+ // Take a stable snapshot, and check if we raced
+ final List<Entry<TransactionIdentifier, Promise<Object>>> priorReadOnlyTxPromiseEntries =
+ new ArrayList<>(priorReadOnlyTxPromises.entrySet());
+ if (priorReadOnlyTxPromiseEntries.isEmpty()) {
+ return future;
+ }
+
+ final List<Future<Object>> priorReadOnlyTxFutures = new ArrayList<>(priorReadOnlyTxPromiseEntries.size());
+ for (Entry<TransactionIdentifier, Promise<Object>> entry: priorReadOnlyTxPromiseEntries) {
+ LOG.debug("Tx: {} - waiting on future for prior read-only Tx {}", txId, entry.getKey());
+ priorReadOnlyTxFutures.add(entry.getValue().future());
+ }
+
+ final Future<Iterable<Object>> combinedFutures = Futures.sequence(priorReadOnlyTxFutures,
+ getActorUtils().getClientDispatcher());
+
+ final Promise<T> returnPromise = Futures.promise();
+ final OnComplete<Iterable<Object>> onComplete = new OnComplete<>() {
+ @Override
+ public void onComplete(final Throwable failure, final Iterable<Object> notUsed) {
+ LOG.debug("Tx: {} - prior read-only Tx futures complete", txId);
+
+ // Complete the returned Promise with the original Future.
+ returnPromise.completeWith(future);
+ }
+ };
+
+ combinedFutures.onComplete(onComplete, getActorUtils().getClientDispatcher());
return returnPromise.future();
}
@Override
- protected <T> void onTransactionReady(final TransactionIdentifier transaction, final Collection<Future<T>> cohortFutures) {
+ protected <T> void onTransactionReady(final TransactionIdentifier transaction,
+ final Collection<Future<T>> cohortFutures) {
final State localState = currentState;
- Preconditions.checkState(localState instanceof Allocated, "Readying transaction %s while state is %s", transaction, localState);
+ 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);
+ 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()) {
}
// Combine the ready Futures into 1
- final Future<Iterable<T>> combined = akka.dispatch.Futures.sequence(
- cohortFutures, getActorContext().getClientDispatcher());
+ final Future<Iterable<T>> combined = Futures.sequence(cohortFutures, getActorUtils().getClientDispatcher());
// Record the we have outstanding futures
final State newState = new Submitted(transaction, combined);
public void onComplete(final Throwable arg0, final Iterable<T> arg1) {
STATE_UPDATER.compareAndSet(TransactionChainProxy.this, newState, IDLE_STATE);
}
- }, getActorContext().getClientDispatcher());
+ }, getActorUtils().getClientDispatcher());
}
@Override
- protected TransactionIdentifier nextIdentifier() {
- return TransactionIdentifier.create(getMemberName(), TX_COUNTER.getAndIncrement(), transactionChainId);
+ protected void onTransactionContextCreated(final TransactionIdentifier transactionId) {
+ Promise<Object> promise = priorReadOnlyTxPromises.remove(transactionId);
+ if (promise != null) {
+ promise.success(null);
+ }
}
}