Split TransactionChainProxy.combineWithPriorReadOnlyTxFutures()
[controller.git] / opendaylight / md-sal / sal-distributed-datastore / src / main / java / org / opendaylight / controller / cluster / datastore / TransactionChainProxy.java
index cf00d5fa39e3d317fe99af05d2f30f112fcb6f22..4ef89b4684c907923274ee1fb4ef0ae6d554da27 100644 (file)
@@ -7,30 +7,29 @@
  */
 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.List;
 import java.util.Map.Entry;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ConcurrentMap;
-import java.util.concurrent.atomic.AtomicInteger;
 import java.util.concurrent.atomic.AtomicReferenceFieldUpdater;
-import java.util.function.Function;
-import javax.annotation.Nonnull;
-import org.opendaylight.controller.cluster.datastore.identifiers.TransactionChainIdentifier;
-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;
@@ -41,8 +40,9 @@ import scala.concurrent.Promise;
  * 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.
@@ -57,13 +57,13 @@ final class TransactionChainProxy extends AbstractTransactionContextFactory<Loca
         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
@@ -98,7 +98,7 @@ final class TransactionChainProxy extends AbstractTransactionContextFactory<Loca
         }
     }
 
-    private static abstract class DefaultState extends State {
+    private abstract static class DefaultState extends State {
         @Override
         final Future<?> previousFuture() {
             return null;
@@ -115,16 +115,14 @@ final class TransactionChainProxy extends AbstractTransactionContextFactory<Loca
     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 TransactionChainIdentifier transactionChainId;
     private final TransactionContextFactory parent;
     private volatile State currentState = IDLE_STATE;
 
@@ -132,34 +130,29 @@ final class TransactionChainProxy extends AbstractTransactionContextFactory<Loca
      * 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>
+     * <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<>();
-
-    TransactionChainProxy(final TransactionContextFactory parent) {
-        super(parent.getActorContext());
+    private final ConcurrentMap<TransactionIdentifier, Promise<Object>> priorReadOnlyTxPromises =
+            new ConcurrentHashMap<>();
 
-        transactionChainId = new TransactionChainIdentifier(parent.getActorContext().getCurrentMemberName(), CHAIN_COUNTER.incrementAndGet());
+    TransactionChainProxy(final TransactionContextFactory parent, final LocalHistoryIdentifier historyId) {
+        super(parent.getActorUtils(), historyId);
         this.parent = parent;
     }
 
-    public String getTransactionChainId() {
-        return transactionChainId.toString();
-    }
-
     @Override
     public DOMStoreReadTransaction newReadOnlyTransaction() {
         currentState.checkReady();
@@ -170,13 +163,13 @@ final class TransactionChainProxy extends AbstractTransactionContextFactory<Loca
 
     @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);
     }
 
@@ -186,12 +179,8 @@ final class TransactionChainProxy extends AbstractTransactionContextFactory<Loca
 
         // Send a close transaction chain request to each and every shard
 
-        getActorContext().broadcast(new Function<Short, Object>() {
-            @Override
-            public Object apply(Short version) {
-                return new CloseTransactionChain(transactionChainId.toString(), version).toSerializable();
-            }
-        });
+        getActorUtils().broadcast(version -> new CloseTransactionChain(getHistoryId(), version).toSerializable(),
+                CloseTransactionChain.class);
     }
 
     private TransactionProxy allocateWriteTransaction(final TransactionType type) {
@@ -204,7 +193,8 @@ final class TransactionChainProxy extends AbstractTransactionContextFactory<Loca
     }
 
     @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;
@@ -229,12 +219,12 @@ final class TransactionChainProxy extends AbstractTransactionContextFactory<Loca
 
         final String previousTransactionId;
 
-        if(localState instanceof Pending){
+        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 {}", getTransactionChainId());
+            LOG.debug("Waiting for ready futures on chain {}", getHistoryId());
         }
 
         previous = combineFutureWithPossiblePriorReadOnlyTxFutures(previous, txId);
@@ -260,52 +250,59 @@ final class TransactionChainProxy extends AbstractTransactionContextFactory<Loca
             }
         };
 
-        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) {
-        if(!priorReadOnlyTxPromises.containsKey(txId) && !priorReadOnlyTxPromises.isEmpty()) {
-            Collection<Entry<TransactionIdentifier, Promise<Object>>> priorReadOnlyTxPromiseEntries =
-                    new ArrayList<>(priorReadOnlyTxPromises.entrySet());
-            if(priorReadOnlyTxPromiseEntries.isEmpty()) {
-                return future;
-            }
+        return priorReadOnlyTxPromises.isEmpty() || priorReadOnlyTxPromises.containsKey(txId) ? future
+                // Tough luck, we need do some work
+                : combineWithPriorReadOnlyTxFutures(future, txId);
+    }
 
-            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());
-            }
+    // 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());
+        }
 
-            Future<Iterable<Object>> combinedFutures = Futures.sequence(priorReadOnlyTxFutures,
-                    getActorContext().getClientDispatcher());
+        final Future<Iterable<Object>> combinedFutures = Futures.sequence(priorReadOnlyTxFutures,
+            getActorUtils().getClientDispatcher());
 
-            final Promise<T> returnPromise = Futures.promise();
-            final OnComplete<Iterable<Object>> onComplete = new OnComplete<Iterable<Object>>() {
-                @Override
-                public void onComplete(final Throwable failure, final Iterable<Object> notUsed) {
-                    LOG.debug("Tx: {} - prior read-only Tx futures complete", txId);
+        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);
-                }
-            };
+                // Complete the returned Promise with the original Future.
+                returnPromise.completeWith(future);
+            }
+        };
 
-            combinedFutures.onComplete(onComplete, getActorContext().getClientDispatcher());
-            return returnPromise.future();
-        } else {
-            return 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()) {
@@ -314,7 +311,7 @@ final class TransactionChainProxy extends AbstractTransactionContextFactory<Loca
         }
 
         // Combine the ready Futures into 1
-        final Future<Iterable<T>> combined = 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);
@@ -327,19 +324,14 @@ final class TransactionChainProxy extends AbstractTransactionContextFactory<Loca
             public void onComplete(final Throwable arg0, final Iterable<T> arg1) {
                 STATE_UPDATER.compareAndSet(TransactionChainProxy.this, newState, IDLE_STATE);
             }
-        }, getActorContext().getClientDispatcher());
+        }, getActorUtils().getClientDispatcher());
     }
 
     @Override
-    protected void onTransactionContextCreated(@Nonnull TransactionIdentifier transactionId) {
+    protected void onTransactionContextCreated(final TransactionIdentifier transactionId) {
         Promise<Object> promise = priorReadOnlyTxPromises.remove(transactionId);
-        if(promise != null) {
+        if (promise != null) {
             promise.success(null);
         }
     }
-
-    @Override
-    protected TransactionIdentifier nextIdentifier() {
-        return transactionChainId.newTransactionIdentifier();
-    }
 }