+++ /dev/null
-/*
- * Copyright (c) 2014 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 com.google.common.annotations.VisibleForTesting;
-import com.google.common.base.Function;
-import com.google.common.base.Optional;
-import com.google.common.base.Preconditions;
-import com.google.common.base.Supplier;
-import com.google.common.collect.Iterables;
-import com.google.common.util.concurrent.CheckedFuture;
-import com.google.common.util.concurrent.Futures;
-import com.google.common.util.concurrent.ListenableFuture;
-import com.google.common.util.concurrent.MoreExecutors;
-import com.google.common.util.concurrent.SettableFuture;
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.List;
-import java.util.Map;
-import java.util.Map.Entry;
-import java.util.Set;
-import java.util.TreeMap;
-import org.opendaylight.controller.cluster.access.concepts.TransactionIdentifier;
-import org.opendaylight.controller.cluster.datastore.messages.AbstractRead;
-import org.opendaylight.controller.cluster.datastore.messages.DataExists;
-import org.opendaylight.controller.cluster.datastore.messages.ReadData;
-import org.opendaylight.controller.cluster.datastore.modification.AbstractModification;
-import org.opendaylight.controller.cluster.datastore.modification.DeleteModification;
-import org.opendaylight.controller.cluster.datastore.modification.MergeModification;
-import org.opendaylight.controller.cluster.datastore.modification.WriteModification;
-import org.opendaylight.controller.cluster.datastore.utils.ActorContext;
-import org.opendaylight.controller.cluster.datastore.utils.NormalizedNodeAggregator;
-import org.opendaylight.mdsal.common.api.MappingCheckedFuture;
-import org.opendaylight.mdsal.common.api.ReadFailedException;
-import org.opendaylight.mdsal.dom.spi.store.AbstractDOMStoreTransaction;
-import org.opendaylight.mdsal.dom.spi.store.DOMStoreReadWriteTransaction;
-import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
-import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
-import org.opendaylight.yangtools.yang.data.api.schema.tree.DataValidationFailedException;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-import scala.concurrent.Future;
-import scala.concurrent.Promise;
-
-/**
- * A transaction potentially spanning multiple backend shards.
- */
-public class TransactionProxy extends AbstractDOMStoreTransaction<TransactionIdentifier>
- implements DOMStoreReadWriteTransaction {
- private enum TransactionState {
- OPEN,
- READY,
- CLOSED,
- }
-
- private static final Logger LOG = LoggerFactory.getLogger(TransactionProxy.class);
-
- // Global lock used for transactions spanning multiple shards - synchronizes sending of the ready messages
- // for atomicity to avoid potential deadlock with concurrent transactions spanning the same shards as outlined
- // in the following scenario:
- //
- // - Tx1 sends ready message to shard A
- // - Tx2 sends ready message to shard A
- // - Tx2 sends ready message to shard B
- // - Tx1 sends ready message to shard B
- //
- // This scenario results in deadlock: after Tx1 canCommits to shard A, it can't proceed with shard B until Tx2
- // completes as Tx2 was readied first on shard B. However Tx2 cannot make progress because it's waiting to canCommit
- // on shard A which is blocked by Tx1.
- //
- // The global lock avoids this as it forces the ready messages to be sent in a predictable order:
- //
- // - Tx1 sends ready message to shard A
- // - Tx1 sends ready message to shard B
- // - Tx2 sends ready message to shard A
- // - Tx2 sends ready message to shard B
- //
- private static final Object GLOBAL_TX_READY_LOCK = new Object();
-
- private final Map<String, TransactionContextWrapper> txContextWrappers = new TreeMap<>();
- private final AbstractTransactionContextFactory<?> txContextFactory;
- private final TransactionType type;
- private TransactionState state = TransactionState.OPEN;
-
- @VisibleForTesting
- public TransactionProxy(final AbstractTransactionContextFactory<?> txContextFactory, final TransactionType type) {
- super(txContextFactory.nextIdentifier(), txContextFactory.getActorContext().getDatastoreContext()
- .isTransactionDebugContextEnabled());
- this.txContextFactory = txContextFactory;
- this.type = Preconditions.checkNotNull(type);
-
- LOG.debug("New {} Tx - {}", type, getIdentifier());
- }
-
- @Override
- public CheckedFuture<Boolean, ReadFailedException> exists(final YangInstanceIdentifier path) {
- return executeRead(shardNameFromIdentifier(path), new DataExists(path, DataStoreVersions.CURRENT_VERSION));
- }
-
- private <T> CheckedFuture<T, ReadFailedException> executeRead(final String shardName,
- final AbstractRead<T> readCmd) {
- Preconditions.checkState(type != TransactionType.WRITE_ONLY,
- "Reads from write-only transactions are not allowed");
-
- LOG.trace("Tx {} {} {}", getIdentifier(), readCmd.getClass().getSimpleName(), readCmd.getPath());
-
- final SettableFuture<T> proxyFuture = SettableFuture.create();
- TransactionContextWrapper contextWrapper = getContextWrapper(shardName);
- contextWrapper.maybeExecuteTransactionOperation(new TransactionOperation() {
- @Override
- public void invoke(final TransactionContext transactionContext, final Boolean havePermit) {
- transactionContext.executeRead(readCmd, proxyFuture, havePermit);
- }
- });
-
- return MappingCheckedFuture.create(proxyFuture, ReadFailedException.MAPPER);
- }
-
- @Override
- public CheckedFuture<Optional<NormalizedNode<?, ?>>, ReadFailedException> read(final YangInstanceIdentifier path) {
- Preconditions.checkState(type != TransactionType.WRITE_ONLY,
- "Reads from write-only transactions are not allowed");
- Preconditions.checkNotNull(path, "path should not be null");
-
- LOG.trace("Tx {} read {}", getIdentifier(), path);
- return path.isEmpty() ? readAllData() : singleShardRead(shardNameFromIdentifier(path), path);
- }
-
- private CheckedFuture<Optional<NormalizedNode<?, ?>>, ReadFailedException> singleShardRead(
- final String shardName, final YangInstanceIdentifier path) {
- return executeRead(shardName, new ReadData(path, DataStoreVersions.CURRENT_VERSION));
- }
-
- private CheckedFuture<Optional<NormalizedNode<?, ?>>, ReadFailedException> readAllData() {
- final Set<String> allShardNames = txContextFactory.getActorContext().getConfiguration().getAllShardNames();
- final Collection<CheckedFuture<Optional<NormalizedNode<?, ?>>, ReadFailedException>> futures =
- new ArrayList<>(allShardNames.size());
-
- for (String shardName : allShardNames) {
- futures.add(singleShardRead(shardName, YangInstanceIdentifier.EMPTY));
- }
-
- final ListenableFuture<List<Optional<NormalizedNode<?, ?>>>> listFuture = Futures.allAsList(futures);
- final ListenableFuture<Optional<NormalizedNode<?, ?>>> aggregateFuture;
-
- aggregateFuture = Futures.transform(listFuture,
- (Function<List<Optional<NormalizedNode<?, ?>>>, Optional<NormalizedNode<?, ?>>>) input -> {
- try {
- return NormalizedNodeAggregator.aggregate(YangInstanceIdentifier.EMPTY, input,
- txContextFactory.getActorContext().getSchemaContext(),
- txContextFactory.getActorContext().getDatastoreContext().getLogicalStoreType());
- } catch (DataValidationFailedException e) {
- throw new IllegalArgumentException("Failed to aggregate", e);
- }
- }, MoreExecutors.directExecutor());
-
- return MappingCheckedFuture.create(aggregateFuture, ReadFailedException.MAPPER);
- }
-
- @Override
- public void delete(final YangInstanceIdentifier path) {
- executeModification(new DeleteModification(path));
- }
-
- @Override
- public void merge(final YangInstanceIdentifier path, final NormalizedNode<?, ?> data) {
- executeModification(new MergeModification(path, data));
- }
-
- @Override
- public void write(final YangInstanceIdentifier path, final NormalizedNode<?, ?> data) {
- executeModification(new WriteModification(path, data));
- }
-
- private void executeModification(final AbstractModification modification) {
- checkModificationState();
-
- LOG.trace("Tx {} executeModification {} {}", getIdentifier(), modification.getClass().getSimpleName(),
- modification.getPath());
-
- TransactionContextWrapper contextWrapper = getContextWrapper(modification.getPath());
- contextWrapper.maybeExecuteTransactionOperation(new TransactionOperation() {
- @Override
- protected void invoke(final TransactionContext transactionContext, final Boolean havePermit) {
- transactionContext.executeModification(modification, havePermit);
- }
- });
- }
-
- private void checkModificationState() {
- Preconditions.checkState(type != TransactionType.READ_ONLY,
- "Modification operation on read-only transaction is not allowed");
- Preconditions.checkState(state == TransactionState.OPEN,
- "Transaction is sealed - further modifications are not allowed");
- }
-
- private boolean seal(final TransactionState newState) {
- if (state == TransactionState.OPEN) {
- state = newState;
- return true;
- } else {
- return false;
- }
- }
-
- @Override
- public final void close() {
- if (!seal(TransactionState.CLOSED)) {
- Preconditions.checkState(state == TransactionState.CLOSED, "Transaction %s is ready, it cannot be closed",
- getIdentifier());
- // Idempotent no-op as per AutoCloseable recommendation
- return;
- }
-
- for (TransactionContextWrapper contextWrapper : txContextWrappers.values()) {
- contextWrapper.maybeExecuteTransactionOperation(new TransactionOperation() {
- @Override
- public void invoke(final TransactionContext transactionContext, final Boolean havePermit) {
- transactionContext.closeTransaction();
- }
- });
- }
-
-
- txContextWrappers.clear();
- }
-
- @Override
- public final AbstractThreePhaseCommitCohort<?> ready() {
- Preconditions.checkState(type != TransactionType.READ_ONLY, "Read-only transactions cannot be readied");
-
- final boolean success = seal(TransactionState.READY);
- Preconditions.checkState(success, "Transaction %s is %s, it cannot be readied", getIdentifier(), state);
-
- LOG.debug("Tx {} Readying {} components for commit", getIdentifier(), txContextWrappers.size());
-
- final AbstractThreePhaseCommitCohort<?> ret;
- switch (txContextWrappers.size()) {
- case 0:
- ret = NoOpDOMStoreThreePhaseCommitCohort.INSTANCE;
- break;
- case 1:
- final Entry<String, TransactionContextWrapper> e = Iterables.getOnlyElement(
- txContextWrappers.entrySet());
- ret = createSingleCommitCohort(e.getKey(), e.getValue());
- break;
- default:
- ret = createMultiCommitCohort(txContextWrappers.entrySet());
- }
-
- txContextFactory.onTransactionReady(getIdentifier(), ret.getCohortFutures());
-
- final Throwable debugContext = getDebugContext();
- return debugContext == null ? ret : new DebugThreePhaseCommitCohort(getIdentifier(), ret, debugContext);
- }
-
- @SuppressWarnings({ "rawtypes", "unchecked" })
- private AbstractThreePhaseCommitCohort<?> createSingleCommitCohort(final String shardName,
- final TransactionContextWrapper contextWrapper) {
-
- LOG.debug("Tx {} Readying transaction for shard {}", getIdentifier(), shardName);
-
- final OperationCallback.Reference operationCallbackRef =
- new OperationCallback.Reference(OperationCallback.NO_OP_CALLBACK);
-
- final TransactionContext transactionContext = contextWrapper.getTransactionContext();
- final Future future;
- if (transactionContext == null) {
- final Promise promise = akka.dispatch.Futures.promise();
- contextWrapper.maybeExecuteTransactionOperation(new TransactionOperation() {
- @Override
- public void invoke(final TransactionContext newTransactionContext, final Boolean havePermit) {
- promise.completeWith(getDirectCommitFuture(newTransactionContext, operationCallbackRef,
- havePermit));
- }
- });
- future = promise.future();
- } else {
- // avoid the creation of a promise and a TransactionOperation
- future = getDirectCommitFuture(transactionContext, operationCallbackRef, null);
- }
-
- return new SingleCommitCohortProxy(txContextFactory.getActorContext(), future, getIdentifier(),
- operationCallbackRef);
- }
-
- private Future<?> getDirectCommitFuture(final TransactionContext transactionContext,
- final OperationCallback.Reference operationCallbackRef, final Boolean havePermit) {
- TransactionRateLimitingCallback rateLimitingCallback = new TransactionRateLimitingCallback(
- txContextFactory.getActorContext());
- operationCallbackRef.set(rateLimitingCallback);
- rateLimitingCallback.run();
- return transactionContext.directCommit(havePermit);
- }
-
- private AbstractThreePhaseCommitCohort<ActorSelection> createMultiCommitCohort(
- final Set<Entry<String, TransactionContextWrapper>> txContextWrapperEntries) {
-
- final List<ThreePhaseCommitCohortProxy.CohortInfo> cohorts = new ArrayList<>(txContextWrapperEntries.size());
-
- synchronized (GLOBAL_TX_READY_LOCK) {
- for (Entry<String, TransactionContextWrapper> e : txContextWrapperEntries) {
- LOG.debug("Tx {} Readying transaction for shard {}", getIdentifier(), e.getKey());
-
- final TransactionContextWrapper wrapper = e.getValue();
-
- // The remote tx version is obtained the via TransactionContext which may not be available yet so
- // we pass a Supplier to dynamically obtain it. Once the ready Future is resolved the
- // TransactionContext is available.
- Supplier<Short> txVersionSupplier = () -> wrapper.getTransactionContext().getTransactionVersion();
-
- cohorts.add(new ThreePhaseCommitCohortProxy.CohortInfo(wrapper.readyTransaction(), txVersionSupplier));
- }
- }
-
- return new ThreePhaseCommitCohortProxy(txContextFactory.getActorContext(), cohorts, getIdentifier());
- }
-
- private String shardNameFromIdentifier(final YangInstanceIdentifier path) {
- return txContextFactory.getActorContext().getShardStrategyFactory().getStrategy(path).findShard(path);
- }
-
- private TransactionContextWrapper getContextWrapper(final YangInstanceIdentifier path) {
- return getContextWrapper(shardNameFromIdentifier(path));
- }
-
- private TransactionContextWrapper getContextWrapper(final String shardName) {
- final TransactionContextWrapper existing = txContextWrappers.get(shardName);
- if (existing != null) {
- return existing;
- }
-
- final TransactionContextWrapper fresh = txContextFactory.newTransactionContextWrapper(this, shardName);
- txContextWrappers.put(shardName, fresh);
- return fresh;
- }
-
- TransactionType getType() {
- return type;
- }
-
- boolean isReady() {
- return state != TransactionState.OPEN;
- }
-
- ActorContext getActorContext() {
- return txContextFactory.getActorContext();
- }
-}