package org.opendaylight.mdsal.dom.broker;
import com.google.common.base.Preconditions;
-import com.google.common.collect.BiMap;
-import com.google.common.collect.ImmutableBiMap;
-import com.google.common.collect.ImmutableBiMap.Builder;
-import com.google.common.collect.ImmutableMap;
+import com.google.common.base.Verify;
import com.google.common.collect.ImmutableSet;
import java.util.Collection;
-import java.util.Collections;
-import java.util.HashMap;
-import java.util.LinkedList;
import java.util.Map;
-import java.util.Map.Entry;
-import java.util.Queue;
import java.util.Set;
+import java.util.concurrent.atomic.AtomicIntegerFieldUpdater;
+import java.util.concurrent.atomic.AtomicReferenceFieldUpdater;
import javax.annotation.concurrent.GuardedBy;
+import org.opendaylight.mdsal.dom.api.DOMDataTreeCursorAwareTransaction;
import org.opendaylight.mdsal.dom.api.DOMDataTreeIdentifier;
import org.opendaylight.mdsal.dom.api.DOMDataTreeProducer;
import org.opendaylight.mdsal.dom.api.DOMDataTreeProducerBusyException;
import org.opendaylight.mdsal.dom.api.DOMDataTreeProducerException;
import org.opendaylight.mdsal.dom.api.DOMDataTreeShard;
-import org.opendaylight.mdsal.dom.api.DOMDataWriteTransaction;
-import org.opendaylight.mdsal.dom.spi.store.DOMStore;
-import org.opendaylight.mdsal.dom.spi.store.DOMStoreTransactionChain;
-import org.opendaylight.mdsal.dom.spi.store.DOMStoreWriteTransaction;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
-final class ShardedDOMDataTreeProducer implements DOMDataTreeProducer {
+class ShardedDOMDataTreeProducer implements DOMDataTreeProducer {
private static final Logger LOG = LoggerFactory.getLogger(ShardedDOMDataTreeProducer.class);
- private final BiMap<DOMDataTreeShard, DOMStoreTransactionChain> shardToChain;
- private final Map<DOMDataTreeIdentifier, DOMDataTreeShard> idToShard;
+
+ private final Set<DOMDataTreeIdentifier> subtrees;
private final ShardedDOMDataTree dataTree;
- @GuardedBy("this")
- private Map<DOMDataTreeIdentifier, DOMDataTreeProducer> children = Collections.emptyMap();
- @GuardedBy("this")
- private DOMDataWriteTransaction openTx;
- @GuardedBy("this")
- private boolean closed;
+ private static final AtomicReferenceFieldUpdater<ShardedDOMDataTreeProducer, ShardedDOMDataTreeWriteTransaction>
+ CURRENT_UPDATER = AtomicReferenceFieldUpdater.newUpdater(ShardedDOMDataTreeProducer.class,
+ ShardedDOMDataTreeWriteTransaction.class, "currentTx");
+ private volatile ShardedDOMDataTreeWriteTransaction currentTx;
- @GuardedBy("this")
- private ShardedDOMDataTreeListenerContext<?> attachedListener;
+ private static final AtomicReferenceFieldUpdater<ShardedDOMDataTreeProducer, ShardedDOMDataTreeWriteTransaction>
+ OPEN_UPDATER = AtomicReferenceFieldUpdater.newUpdater(ShardedDOMDataTreeProducer.class,
+ ShardedDOMDataTreeWriteTransaction.class, "openTx");
+ private volatile ShardedDOMDataTreeWriteTransaction openTx;
- ShardedDOMDataTreeProducer(final ShardedDOMDataTree dataTree, final Map<DOMDataTreeIdentifier, DOMDataTreeShard> shardMap, final Set<DOMDataTreeShard> shards) {
- this.dataTree = Preconditions.checkNotNull(dataTree);
+ private static final AtomicReferenceFieldUpdater<ShardedDOMDataTreeProducer, ShardedDOMDataTreeWriteTransaction>
+ LAST_UPDATER = AtomicReferenceFieldUpdater.newUpdater(ShardedDOMDataTreeProducer.class,
+ ShardedDOMDataTreeWriteTransaction.class, "lastTx");
+ private volatile ShardedDOMDataTreeWriteTransaction lastTx;
- // Create shard -> chain map
- final Builder<DOMDataTreeShard, DOMStoreTransactionChain> cb = ImmutableBiMap.builder();
- final Queue<Exception> es = new LinkedList<>();
-
- for (final DOMDataTreeShard s : shards) {
- if (s instanceof DOMStore) {
- try {
- final DOMStoreTransactionChain c = ((DOMStore)s).createTransactionChain();
- LOG.trace("Using DOMStore chain {} to access shard {}", c, s);
- cb.put(s, c);
- } catch (final Exception e) {
- LOG.error("Failed to instantiate chain for shard {}", s, e);
- es.add(e);
- }
- } else {
- LOG.error("Unhandled shard instance type {}", s.getClass());
- }
- }
- this.shardToChain = cb.build();
-
- // An error was encountered, close chains and report the error
- if (shardToChain.size() != shards.size()) {
- for (final DOMStoreTransactionChain c : shardToChain.values()) {
- try {
- c.close();
- } catch (final Exception e) {
- LOG.warn("Exception raised while closing chain {}", c, e);
- }
- }
+ private static final AtomicIntegerFieldUpdater<ShardedDOMDataTreeProducer> CLOSED_UPDATER =
+ AtomicIntegerFieldUpdater.newUpdater(ShardedDOMDataTreeProducer.class, "closed");
+ private volatile int closed;
- final IllegalStateException e = new IllegalStateException("Failed to completely allocate contexts", es.poll());
- while (!es.isEmpty()) {
- e.addSuppressed(es.poll());
- }
+ private volatile ShardedDOMDataTreeListenerContext<?> attachedListener;
+ private volatile ProducerLayout layout;
- throw e;
- }
+ private ShardedDOMDataTreeProducer(final ShardedDOMDataTree dataTree,
+ final Collection<DOMDataTreeIdentifier> subtrees,
+ final Map<DOMDataTreeIdentifier, DOMDataTreeShard> shardMap) {
+ this.dataTree = Preconditions.checkNotNull(dataTree);
+ this.subtrees = ImmutableSet.copyOf(subtrees);
+ this.layout = ProducerLayout.create(shardMap);
+ }
- idToShard = ImmutableMap.copyOf(shardMap);
+ static DOMDataTreeProducer create(final ShardedDOMDataTree dataTree,
+ final Collection<DOMDataTreeIdentifier> subtrees,
+ final Map<DOMDataTreeIdentifier, DOMDataTreeShard> shardMap) {
+ return new ShardedDOMDataTreeProducer(dataTree, subtrees, shardMap);
}
- @Override
- public synchronized DOMDataWriteTransaction createTransaction(final boolean isolated) {
- Preconditions.checkState(!closed, "Producer is already closed");
+ private void checkNotClosed() {
+ Preconditions.checkState(closed == 0, "Producer is already closed");
+ }
+
+ private void checkIdle() {
Preconditions.checkState(openTx == null, "Transaction %s is still open", openTx);
+ }
- // Allocate backing transactions
- final Map<DOMDataTreeShard, DOMStoreWriteTransaction> shardToTx = new HashMap<>();
- for (final Entry<DOMDataTreeShard, DOMStoreTransactionChain> e : shardToChain.entrySet()) {
- shardToTx.put(e.getKey(), e.getValue().newWriteOnlyTransaction());
- }
+ void subshardAdded(final Map<DOMDataTreeIdentifier, DOMDataTreeShard> shardMap) {
+ checkIdle();
+
+ layout = layout.reshard(shardMap);
+ }
- // Create the ID->transaction map
- final ImmutableMap.Builder<DOMDataTreeIdentifier, DOMStoreWriteTransaction> b = ImmutableMap.builder();
- for (final Entry<DOMDataTreeIdentifier, DOMDataTreeShard> e : idToShard.entrySet()) {
- b.put(e.getKey(), shardToTx.get(e.getValue()));
+ @Override
+ public DOMDataTreeCursorAwareTransaction createTransaction(final boolean isolated) {
+ checkNotClosed();
+ checkIdle();
+
+ LOG.debug("Creating transaction from producer {}", this);
+
+ final ShardedDOMDataTreeWriteTransaction current = CURRENT_UPDATER.getAndSet(this, null);
+ final ShardedDOMDataTreeWriteTransaction ret;
+ if (isolated) {
+ ret = createIsolatedTransaction(layout, current);
+ } else {
+ ret = createReusedTransaction(layout, current);
}
- final ShardedDOMDataWriteTransaction ret = new ShardedDOMDataWriteTransaction(this, b.build());
- openTx = ret;
+ final boolean success = OPEN_UPDATER.compareAndSet(this, null, ret);
+ Preconditions.checkState(success, "Illegal concurrent access to producer %s detected", this);
return ret;
}
+ // This may look weird, but this has side-effects on local's producers, hence it needs to be properly synchronized
+ // so that it happens-after submitTransaction() which may have been stolen by a callback.
@GuardedBy("this")
- private boolean haveSubtree(final DOMDataTreeIdentifier subtree) {
- for (final DOMDataTreeIdentifier i : idToShard.keySet()) {
- if (i.contains(subtree)) {
- return true;
- }
+ private ShardedDOMDataTreeWriteTransaction createTransaction(final ProducerLayout local) {
+ return new ShardedDOMDataTreeWriteTransaction(this, local.createTransactions(), local);
+
+ }
+
+ // Isolated case. If we have a previous transaction, submit it before returning this one.
+ private synchronized ShardedDOMDataTreeWriteTransaction createIsolatedTransaction(
+ final ProducerLayout local, final ShardedDOMDataTreeWriteTransaction current) {
+ if (current != null) {
+ submitTransaction(current);
}
- return false;
+ return createTransaction(local);
}
- @GuardedBy("this")
- private DOMDataTreeProducer lookupChild(final DOMDataTreeIdentifier s) {
- for (final Entry<DOMDataTreeIdentifier, DOMDataTreeProducer> e : children.entrySet()) {
- if (e.getKey().contains(s)) {
- return e.getValue();
+ private ShardedDOMDataTreeWriteTransaction createReusedTransaction(final ProducerLayout local,
+ final ShardedDOMDataTreeWriteTransaction current) {
+ if (current != null) {
+ // Lock-free fast path
+ if (local.equals(current.getLayout())) {
+ LOG.debug("Reusing previous transaction {} since there is still a transaction inflight",
+ current.getIdentifier());
+ return current;
+ }
+
+ synchronized (this) {
+ submitTransaction(current);
+ return createTransaction(local);
}
}
- return null;
+ // Null indicates we have not seen a previous transaction -- which does not mean it is ready, as it may have
+ // been stolen and in is process of being submitted.
+ synchronized (this) {
+ return createTransaction(local);
+ }
+ }
+
+ @GuardedBy("this")
+ private void submitTransaction(final ShardedDOMDataTreeWriteTransaction tx) {
+ lastTx = tx;
+ tx.doSubmit(this::transactionSuccessful, this::transactionFailed);
}
@Override
- public synchronized DOMDataTreeProducer createProducer(final Collection<DOMDataTreeIdentifier> subtrees) {
- Preconditions.checkState(!closed, "Producer is already closed");
- Preconditions.checkState(openTx == null, "Transaction %s is still open", openTx);
+ public DOMDataTreeProducer createProducer(final Collection<DOMDataTreeIdentifier> subtrees) {
+ checkNotClosed();
+ checkIdle();
+
+ final ProducerLayout local = layout;
for (final DOMDataTreeIdentifier s : subtrees) {
// Check if the subtree was visible at any time
- Preconditions.checkArgument(haveSubtree(s), "Subtree %s was never available in producer %s", s, this);
+ Preconditions.checkArgument(local.haveSubtree(s), "Subtree %s was never available in producer %s", s, this);
// Check if the subtree has not been delegated to a child
- final DOMDataTreeProducer child = lookupChild(s);
+ final DOMDataTreeProducer child = local.lookupChild(s);
Preconditions.checkArgument(child == null, "Subtree %s is delegated to child producer %s", s, child);
// Check if part of the requested subtree is not delegated to a child.
- for (final DOMDataTreeIdentifier c : children.keySet()) {
- if (s.contains(c)) {
- throw new IllegalArgumentException(String.format("Subtree %s cannot be delegated as it is superset of already-delegated %s", s, c));
- }
+ for (final DOMDataTreeIdentifier c : local.getChildTrees()) {
+ Preconditions.checkArgument(!s.contains(c),
+ "Subtree %s cannot be delegated as it is a superset of already-delegated %s", s, c);
}
}
- final DOMDataTreeProducer ret = dataTree.createProducer(this, subtrees);
- final ImmutableMap.Builder<DOMDataTreeIdentifier, DOMDataTreeProducer> cb = ImmutableMap.builder();
- cb.putAll(children);
- for (final DOMDataTreeIdentifier s : subtrees) {
- cb.put(s, ret);
+
+ final DOMDataTreeProducer ret;
+ synchronized (this) {
+ ret = dataTree.createProducer(this, subtrees);
}
- children = cb.build();
+ layout = local.addChild(ret, subtrees);
return ret;
}
- boolean isDelegatedToChild(DOMDataTreeIdentifier path) {
- for (final DOMDataTreeIdentifier c : children.keySet()) {
- if (c.contains(path)) {
- return true;
+ boolean isDelegatedToChild(final DOMDataTreeIdentifier path) {
+ return layout.lookupChild(path) != null;
+ }
+
+ @Override
+ public void close() throws DOMDataTreeProducerException {
+ if (openTx != null) {
+ throw new DOMDataTreeProducerBusyException(String.format("Transaction %s is still open", openTx));
+ }
+
+ if (CLOSED_UPDATER.compareAndSet(this, 0, 1)) {
+ synchronized (this) {
+ dataTree.destroyProducer(this);
}
}
- return false;
}
+ protected Set<DOMDataTreeIdentifier> getSubtrees() {
+ return subtrees;
+ }
- @Override
- public synchronized void close() throws DOMDataTreeProducerException {
- if (!closed) {
- if (openTx != null) {
- throw new DOMDataTreeProducerBusyException(String.format("Transaction %s is still open", openTx));
+ void cancelTransaction(final ShardedDOMDataTreeWriteTransaction transaction) {
+ final boolean success = OPEN_UPDATER.compareAndSet(this, transaction, null);
+ if (success) {
+ LOG.debug("Transaction {} cancelled", transaction);
+ } else {
+ LOG.warn("Transaction {} is not open in producer {}", transaction, this);
+ }
+ }
+
+ // Called when the user submits a transaction
+ void transactionSubmitted(final ShardedDOMDataTreeWriteTransaction transaction) {
+ final boolean wasOpen = OPEN_UPDATER.compareAndSet(this, transaction, null);
+ Preconditions.checkState(wasOpen, "Attempted to submit non-open transaction %s", transaction);
+
+ if (lastTx == null) {
+ // No transaction outstanding, we need to submit it now
+ synchronized (this) {
+ submitTransaction(transaction);
}
- closed = true;
- dataTree.destroyProducer(this);
+ return;
}
- }
- static DOMDataTreeProducer create(final ShardedDOMDataTree dataTree, final Map<DOMDataTreeIdentifier, DOMDataTreeShard> shardMap) {
- /*
- * FIXME: we do not allow multiple multiple shards in a producer because we do not implement the
- * synchronization primitives yet
- */
- final Set<DOMDataTreeShard> shards = ImmutableSet.copyOf(shardMap.values());
- if (shards.size() > 1) {
- throw new UnsupportedOperationException("Cross-shard producers are not supported yet");
+ // There is a potentially-racing submitted transaction. Publish the new one, which may end up being
+ // picked up by processNextTransaction.
+ final boolean success = CURRENT_UPDATER.compareAndSet(this, null, transaction);
+ Verify.verify(success);
+
+ // Now a quick check: if the racing transaction completed in between, it may have missed the current
+ // transaction, hence we need to re-check
+ if (lastTx == null) {
+ submitCurrentTransaction();
}
+ }
- return new ShardedDOMDataTreeProducer(dataTree, shardMap, shards);
+ private void submitCurrentTransaction() {
+ final ShardedDOMDataTreeWriteTransaction current = currentTx;
+ if (current != null) {
+ synchronized (this) {
+ if (CURRENT_UPDATER.compareAndSet(this, current, null)) {
+ submitTransaction(current);
+ }
+ }
+ }
}
- Set<DOMDataTreeIdentifier> getSubtrees() {
- return idToShard.keySet();
+ private void transactionSuccessful(final ShardedDOMDataTreeWriteTransaction tx) {
+ LOG.debug("Transaction {} completed successfully", tx.getIdentifier());
+
+ tx.onTransactionSuccess(null);
+ transactionCompleted(tx);
}
- synchronized void cancelTransaction(final ShardedDOMDataWriteTransaction transaction) {
- if (!openTx.equals(transaction)) {
- LOG.warn("Transaction {} is not open in producer {}", transaction, this);
- return;
- }
+ private void transactionFailed(final ShardedDOMDataTreeWriteTransaction tx, final Throwable throwable) {
+ LOG.debug("Transaction {} failed", tx.getIdentifier(), throwable);
- LOG.debug("Transaction {} cancelled", transaction);
- openTx = null;
+ tx.onTransactionFailure(throwable);
+ // FIXME: transaction failure should result in a hard error
+ transactionCompleted(tx);
}
- synchronized void transactionSubmitted(ShardedDOMDataWriteTransaction transaction) {
- Preconditions.checkState(openTx.equals(transaction));
- openTx = null;
+ private void transactionCompleted(final ShardedDOMDataTreeWriteTransaction tx) {
+ final boolean wasLast = LAST_UPDATER.compareAndSet(this, tx, null);
+ if (wasLast) {
+ submitCurrentTransaction();
+ }
}
- synchronized void boundToListener(ShardedDOMDataTreeListenerContext<?> listener) {
- // FIXME: Add option to dettach
- Preconditions.checkState(this.attachedListener == null,
- "Producer %s is already attached to other listener.",
- listener.getListener());
+ void bindToListener(final ShardedDOMDataTreeListenerContext<?> listener) {
+ Preconditions.checkNotNull(listener);
+
+ final ShardedDOMDataTreeListenerContext<?> local = attachedListener;
+ if (local != null) {
+ throw new IllegalStateException(String.format("Producer %s is already attached to listener %s", this,
+ local.getListener()));
+ }
+
this.attachedListener = listener;
}
}
Code Review / mdsal.git / blobdiff