*/
package org.opendaylight.mdsal.dom.broker;
+import static java.util.Objects.requireNonNull;
+
import com.google.common.base.Preconditions;
import com.google.common.base.Verify;
-import com.google.common.collect.ArrayListMultimap;
-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.collect.ImmutableSet;
-import com.google.common.collect.Multimap;
import java.util.Collection;
-import java.util.Collections;
import java.util.Map;
-import java.util.Map.Entry;
import java.util.Set;
+import java.util.concurrent.atomic.AtomicIntegerFieldUpdater;
import java.util.concurrent.atomic.AtomicReferenceFieldUpdater;
-import javax.annotation.concurrent.GuardedBy;
+import org.checkerframework.checker.lock.qual.GuardedBy;
+import org.checkerframework.checker.lock.qual.Holding;
+import org.opendaylight.mdsal.common.api.CommitInfo;
import org.opendaylight.mdsal.dom.api.DOMDataTreeCursorAwareTransaction;
import org.opendaylight.mdsal.dom.api.DOMDataTreeIdentifier;
+import org.opendaylight.mdsal.dom.api.DOMDataTreeListener;
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.store.inmemory.DOMDataTreeShardProducer;
-import org.opendaylight.mdsal.dom.store.inmemory.WriteableDOMDataTreeShard;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
private final Set<DOMDataTreeIdentifier> subtrees;
private final ShardedDOMDataTree dataTree;
- private BiMap<DOMDataTreeIdentifier, DOMDataTreeShardProducer> idToProducer = ImmutableBiMap.of();
- private Map<DOMDataTreeIdentifier, DOMDataTreeShard> idToShard;
-
private static final AtomicReferenceFieldUpdater<ShardedDOMDataTreeProducer, ShardedDOMDataTreeWriteTransaction>
CURRENT_UPDATER = AtomicReferenceFieldUpdater.newUpdater(ShardedDOMDataTreeProducer.class,
ShardedDOMDataTreeWriteTransaction.class, "currentTx");
- @SuppressWarnings("unused")
private volatile ShardedDOMDataTreeWriteTransaction currentTx;
private static final AtomicReferenceFieldUpdater<ShardedDOMDataTreeProducer, ShardedDOMDataTreeWriteTransaction>
ShardedDOMDataTreeWriteTransaction.class, "lastTx");
private volatile ShardedDOMDataTreeWriteTransaction lastTx;
- @GuardedBy("this")
- private Map<DOMDataTreeIdentifier, DOMDataTreeProducer> children = Collections.emptyMap();
- @GuardedBy("this")
- private boolean closed;
+ private static final AtomicIntegerFieldUpdater<ShardedDOMDataTreeProducer> CLOSED_UPDATER =
+ AtomicIntegerFieldUpdater.newUpdater(ShardedDOMDataTreeProducer.class, "closed");
+ private volatile int closed;
- @GuardedBy("this")
- private ShardedDOMDataTreeListenerContext<?> attachedListener;
+ private volatile DOMDataTreeListener attachedListener;
+ private volatile ProducerLayout layout;
ShardedDOMDataTreeProducer(final ShardedDOMDataTree dataTree,
final Collection<DOMDataTreeIdentifier> subtrees,
- final Map<DOMDataTreeIdentifier, DOMDataTreeShard> shardMap,
- final Multimap<DOMDataTreeShard, DOMDataTreeIdentifier> shardToId) {
- this.dataTree = Preconditions.checkNotNull(dataTree);
- if (!shardToId.isEmpty()) {
- this.idToProducer = mapIdsToProducer(shardToId);
- }
- idToShard = ImmutableMap.copyOf(shardMap);
+ final Map<DOMDataTreeIdentifier, DOMDataTreeShard> shardMap) {
+ this.dataTree = requireNonNull(dataTree);
this.subtrees = ImmutableSet.copyOf(subtrees);
+ this.layout = ProducerLayout.create(shardMap);
}
static DOMDataTreeProducer create(final ShardedDOMDataTree dataTree,
final Collection<DOMDataTreeIdentifier> subtrees,
final Map<DOMDataTreeIdentifier, DOMDataTreeShard> shardMap) {
- final Multimap<DOMDataTreeShard, DOMDataTreeIdentifier> shardToIdentifiers = ArrayListMultimap.create();
- // map which identifier belongs to which shard
- for (final Entry<DOMDataTreeIdentifier, DOMDataTreeShard> entry : shardMap.entrySet()) {
- shardToIdentifiers.put(entry.getValue(), entry.getKey());
- }
+ return new ShardedDOMDataTreeProducer(dataTree, subtrees, shardMap);
+ }
- return new ShardedDOMDataTreeProducer(dataTree, subtrees, shardMap, shardToIdentifiers);
+ private void checkNotClosed() {
+ Preconditions.checkState(closed == 0, "Producer is already closed");
}
- void subshardAdded(final Map<DOMDataTreeIdentifier, DOMDataTreeShard> shardMap) {
+ private void checkIdle() {
Preconditions.checkState(openTx == null, "Transaction %s is still open", openTx);
- final Multimap<DOMDataTreeShard, DOMDataTreeIdentifier> shardToIdentifiers = ArrayListMultimap.create();
- // map which identifier belongs to which shard
- for (final Entry<DOMDataTreeIdentifier, DOMDataTreeShard> entry : shardMap.entrySet()) {
- shardToIdentifiers.put(entry.getValue(), entry.getKey());
- }
- this.idToProducer = mapIdsToProducer(shardToIdentifiers);
- idToShard = ImmutableMap.copyOf(shardMap);
}
- private static BiMap<DOMDataTreeIdentifier, DOMDataTreeShardProducer> mapIdsToProducer(
- final Multimap<DOMDataTreeShard, DOMDataTreeIdentifier> shardToId) {
- final Builder<DOMDataTreeIdentifier, DOMDataTreeShardProducer> idToProducerBuilder = ImmutableBiMap.builder();
- for (final Entry<DOMDataTreeShard, Collection<DOMDataTreeIdentifier>> entry : shardToId.asMap().entrySet()) {
- if (entry.getKey() instanceof WriteableDOMDataTreeShard) {
- //create a single producer for all prefixes in a single shard
- final DOMDataTreeShardProducer producer = ((WriteableDOMDataTreeShard) entry.getKey())
- .createProducer(entry.getValue());
- // id mapped to producers
- for (final DOMDataTreeIdentifier id : entry.getValue()) {
- idToProducerBuilder.put(id, producer);
- }
- } else {
- LOG.error("Unable to create a producer for shard that's not a WriteableDOMDataTreeShard");
- }
- }
-
- return idToProducerBuilder.build();
+ void subshardAdded(final Map<DOMDataTreeIdentifier, DOMDataTreeShard> shardMap) {
+ checkIdle();
+ layout = layout.reshard(shardMap);
}
@Override
- public synchronized DOMDataTreeCursorAwareTransaction createTransaction(final boolean isolated) {
- Preconditions.checkState(!closed, "Producer is already closed");
- Preconditions.checkState(openTx == null, "Transaction %s is still open", openTx);
+ public DOMDataTreeCursorAwareTransaction createTransaction(final boolean isolated) {
+ checkNotClosed();
+ checkIdle();
+
+ LOG.debug("Creating transaction from producer {}", this);
- LOG.debug("Creating transaction from producer");
final ShardedDOMDataTreeWriteTransaction current = CURRENT_UPDATER.getAndSet(this, null);
final ShardedDOMDataTreeWriteTransaction ret;
if (isolated) {
- // Isolated case. If we have a previous transaction, submit it before returning this one.
- if (current != null) {
- submitTransaction(current);
- }
- ret = new ShardedDOMDataTreeWriteTransaction(this, idToProducer, children, true);
+ ret = createIsolatedTransaction(layout, current);
} else {
- // Non-isolated case, see if we can reuse the transaction
- if (current != null) {
- LOG.debug("Reusing previous transaction {} since there is still a transaction inflight",
- current.getIdentifier());
- ret = current;
- } else {
- ret = new ShardedDOMDataTreeWriteTransaction(this, idToProducer, children, false);
- }
+ ret = createReusedTransaction(layout, current);
}
final boolean success = OPEN_UPDATER.compareAndSet(this, null, ret);
- Verify.verify(success);
+ Preconditions.checkState(success, "Illegal concurrent access to producer %s detected", this);
return ret;
}
- private void submitTransaction(final ShardedDOMDataTreeWriteTransaction current) {
- lastTx = current;
- current.doSubmit(this::transactionSuccessful, this::transactionFailed);
+ // 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 ShardedDOMDataTreeWriteTransaction createTransaction(final ProducerLayout local) {
+ return new ShardedDOMDataTreeWriteTransaction(this, local.createTransactions(), local);
+
}
- @GuardedBy("this")
- private boolean haveSubtree(final DOMDataTreeIdentifier subtree) {
- for (final DOMDataTreeIdentifier i : idToShard.keySet()) {
- if (i.contains(subtree)) {
- return true;
- }
+ // 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 domDataTreeIdentifier) {
- for (final Entry<DOMDataTreeIdentifier, DOMDataTreeProducer> e : children.entrySet()) {
- if (e.getKey().contains(domDataTreeIdentifier)) {
- 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);
+ }
+ }
+
+ @Holding("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);
+ @SuppressWarnings("checkstyle:hiddenField")
+ 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(final DOMDataTreeIdentifier path) {
- for (final DOMDataTreeIdentifier c : children.keySet()) {
- if (c.contains(path)) {
- return true;
- }
- }
- return false;
+ return layout.lookupChild(path) != null;
}
-
@Override
- public synchronized void close() throws DOMDataTreeProducerException {
- if (!closed) {
- if (openTx != null) {
- throw new DOMDataTreeProducerBusyException(String.format("Transaction %s is still open", openTx));
- }
+ public void close() throws DOMDataTreeProducerException {
+ if (openTx != null) {
+ throw new DOMDataTreeProducerBusyException(String.format("Transaction %s is still open", openTx));
+ }
- closed = true;
- dataTree.destroyProducer(this);
+ if (CLOSED_UPDATER.compareAndSet(this, 0, 1)) {
+ synchronized (this) {
+ dataTree.destroyProducer(this);
+ layout.close();
+ }
}
}
}
}
- void processTransaction(final ShardedDOMDataTreeWriteTransaction transaction) {
+ // Called when the user submits a transaction
+ void transactionSubmitted(final ShardedDOMDataTreeWriteTransaction transaction) {
final boolean wasOpen = OPEN_UPDATER.compareAndSet(this, transaction, null);
- Verify.verify(wasOpen);
-
- if (lastTx != null) {
- final boolean success = CURRENT_UPDATER.compareAndSet(this, null, transaction);
- Verify.verify(success);
- if (lastTx == null) {
- // Dispatch after requeue
- processCurrentTransaction();
+ 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);
+ }
+
+ return;
+ }
+
+ // 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();
+ }
+ }
+
+ private void submitCurrentTransaction() {
+ final ShardedDOMDataTreeWriteTransaction current = currentTx;
+ if (current != null) {
+ synchronized (this) {
+ if (CURRENT_UPDATER.compareAndSet(this, current, null)) {
+ submitTransaction(current);
+ }
}
- } else {
- submitTransaction(transaction);
}
}
- void transactionSuccessful(final ShardedDOMDataTreeWriteTransaction tx, final Void result) {
+ private void transactionSuccessful(final ShardedDOMDataTreeWriteTransaction tx) {
LOG.debug("Transaction {} completed successfully", tx.getIdentifier());
- tx.onTransactionSuccess(result);
- processNextTransaction(tx);
+ tx.onTransactionSuccess(CommitInfo.empty());
+ transactionCompleted(tx);
}
- void transactionFailed(final ShardedDOMDataTreeWriteTransaction tx, final Throwable throwable) {
+ private void transactionFailed(final ShardedDOMDataTreeWriteTransaction tx, final Throwable throwable) {
LOG.debug("Transaction {} failed", tx.getIdentifier(), throwable);
tx.onTransactionFailure(throwable);
- processNextTransaction(tx);
- }
-
- private void processCurrentTransaction() {
- final ShardedDOMDataTreeWriteTransaction current = CURRENT_UPDATER.getAndSet(this, null);
- if (current != null) {
- submitTransaction(current);
- }
+ // FIXME: transaction failure should result in a hard error
+ transactionCompleted(tx);
}
- private void processNextTransaction(final ShardedDOMDataTreeWriteTransaction tx) {
+ private void transactionCompleted(final ShardedDOMDataTreeWriteTransaction tx) {
final boolean wasLast = LAST_UPDATER.compareAndSet(this, tx, null);
if (wasLast) {
- processCurrentTransaction();
+ submitCurrentTransaction();
}
}
- synchronized void boundToListener(final ShardedDOMDataTreeListenerContext<?> listener) {
- // FIXME: Add option to detach
- Preconditions.checkState(this.attachedListener == null, "Producer %s is already attached to other listener.",
- listener.getListener());
- this.attachedListener = listener;
+ void bindToListener(final DOMDataTreeListener listener) {
+ final DOMDataTreeListener local = attachedListener;
+ Preconditions.checkState(local == null, "Producer %s is already attached to listener %s", this, local);
+ this.attachedListener = requireNonNull(listener);
}
}