dom/mdsal-dom-broker/src/main/java/org/opendaylight/mdsal/dom/broker/ShardedDOMDataTreeProducer.java

   1 /*
   2  * Copyright (c) 2015 Cisco Systems, Inc. and others.  All rights reserved.
   3  *
   4  * This program and the accompanying materials are made available under the
   5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   6  * and is available at http://www.eclipse.org/legal/epl-v10.html
   7  */
   8 package org.opendaylight.mdsal.dom.broker;
   9
  10 import com.google.common.base.Preconditions;
  11 import com.google.common.base.Verify;
  12 import com.google.common.collect.ArrayListMultimap;
  13 import com.google.common.collect.BiMap;
  14 import com.google.common.collect.ImmutableBiMap;
  15 import com.google.common.collect.ImmutableBiMap.Builder;
  16 import com.google.common.collect.ImmutableMap;
  17 import com.google.common.collect.ImmutableSet;
  18 import com.google.common.collect.Multimap;
  19 import java.util.Collection;
  20 import java.util.Collections;
  21 import java.util.Map;
  22 import java.util.Map.Entry;
  23 import java.util.Set;
  24 import java.util.concurrent.atomic.AtomicReferenceFieldUpdater;
  25 import javax.annotation.concurrent.GuardedBy;
  26 import org.opendaylight.mdsal.dom.api.DOMDataTreeCursorAwareTransaction;
  27 import org.opendaylight.mdsal.dom.api.DOMDataTreeIdentifier;
  28 import org.opendaylight.mdsal.dom.api.DOMDataTreeProducer;
  29 import org.opendaylight.mdsal.dom.api.DOMDataTreeProducerBusyException;
  30 import org.opendaylight.mdsal.dom.api.DOMDataTreeProducerException;
  31 import org.opendaylight.mdsal.dom.api.DOMDataTreeShard;
  32 import org.opendaylight.mdsal.dom.store.inmemory.DOMDataTreeShardProducer;
  33 import org.opendaylight.mdsal.dom.store.inmemory.WriteableDOMDataTreeShard;
  34 import org.slf4j.Logger;
  35 import org.slf4j.LoggerFactory;
  36
  37 class ShardedDOMDataTreeProducer implements DOMDataTreeProducer {
  38     private static final Logger LOG = LoggerFactory.getLogger(ShardedDOMDataTreeProducer.class);
  39
  40     private final Set<DOMDataTreeIdentifier> subtrees;
  41     private final ShardedDOMDataTree dataTree;
  42
  43     private BiMap<DOMDataTreeIdentifier, DOMDataTreeShardProducer> idToProducer = ImmutableBiMap.of();
  44     private Map<DOMDataTreeIdentifier, DOMDataTreeShard> idToShard;
  45
  46     private static final AtomicReferenceFieldUpdater<ShardedDOMDataTreeProducer, ShardedDOMDataTreeWriteTransaction>
  47         CURRENT_UPDATER = AtomicReferenceFieldUpdater.newUpdater(ShardedDOMDataTreeProducer.class,
  48             ShardedDOMDataTreeWriteTransaction.class, "currentTx");
  49     @SuppressWarnings("unused")
  50     private volatile ShardedDOMDataTreeWriteTransaction currentTx;
  51
  52     private static final AtomicReferenceFieldUpdater<ShardedDOMDataTreeProducer, ShardedDOMDataTreeWriteTransaction>
  53         OPEN_UPDATER = AtomicReferenceFieldUpdater.newUpdater(ShardedDOMDataTreeProducer.class,
  54             ShardedDOMDataTreeWriteTransaction.class, "openTx");
  55     private volatile ShardedDOMDataTreeWriteTransaction openTx;
  56
  57     private static final AtomicReferenceFieldUpdater<ShardedDOMDataTreeProducer, ShardedDOMDataTreeWriteTransaction>
  58         LAST_UPDATER = AtomicReferenceFieldUpdater.newUpdater(ShardedDOMDataTreeProducer.class,
  59             ShardedDOMDataTreeWriteTransaction.class, "lastTx");
  60     private volatile ShardedDOMDataTreeWriteTransaction lastTx;
  61
  62     @GuardedBy("this")
  63     private Map<DOMDataTreeIdentifier, DOMDataTreeProducer> children = Collections.emptyMap();
  64     @GuardedBy("this")
  65     private boolean closed;
  66
  67     @GuardedBy("this")
  68     private ShardedDOMDataTreeListenerContext<?> attachedListener;
  69
  70     ShardedDOMDataTreeProducer(final ShardedDOMDataTree dataTree,
  71                                final Collection<DOMDataTreeIdentifier> subtrees,
  72                                final Map<DOMDataTreeIdentifier, DOMDataTreeShard> shardMap,
  73                                final Multimap<DOMDataTreeShard, DOMDataTreeIdentifier> shardToId) {
  74         this.dataTree = Preconditions.checkNotNull(dataTree);
  75         if (!shardToId.isEmpty()) {
  76             this.idToProducer = mapIdsToProducer(shardToId);
  77         }
  78         idToShard = ImmutableMap.copyOf(shardMap);
  79         this.subtrees = ImmutableSet.copyOf(subtrees);
  80     }
  81
  82     static DOMDataTreeProducer create(final ShardedDOMDataTree dataTree,
  83                                       final Collection<DOMDataTreeIdentifier> subtrees,
  84                                       final Map<DOMDataTreeIdentifier, DOMDataTreeShard> shardMap) {
  85         final Multimap<DOMDataTreeShard, DOMDataTreeIdentifier> shardToIdentifiers = ArrayListMultimap.create();
  86         // map which identifier belongs to which shard
  87         for (final Entry<DOMDataTreeIdentifier, DOMDataTreeShard> entry : shardMap.entrySet()) {
  88             shardToIdentifiers.put(entry.getValue(), entry.getKey());
  89         }
  90
  91         return new ShardedDOMDataTreeProducer(dataTree, subtrees, shardMap, shardToIdentifiers);
  92     }
  93
  94     void subshardAdded(final Map<DOMDataTreeIdentifier, DOMDataTreeShard> shardMap) {
  95         Preconditions.checkState(openTx == null, "Transaction %s is still open", openTx);
  96         final Multimap<DOMDataTreeShard, DOMDataTreeIdentifier> shardToIdentifiers = ArrayListMultimap.create();
  97         // map which identifier belongs to which shard
  98         for (final Entry<DOMDataTreeIdentifier, DOMDataTreeShard> entry : shardMap.entrySet()) {
  99             shardToIdentifiers.put(entry.getValue(), entry.getKey());
 100         }
 101         this.idToProducer = mapIdsToProducer(shardToIdentifiers);
 102         idToShard = ImmutableMap.copyOf(shardMap);
 103     }
 104
 105     private static BiMap<DOMDataTreeIdentifier, DOMDataTreeShardProducer> mapIdsToProducer(
 106             final Multimap<DOMDataTreeShard, DOMDataTreeIdentifier> shardToId) {
 107         final Builder<DOMDataTreeIdentifier, DOMDataTreeShardProducer> idToProducerBuilder = ImmutableBiMap.builder();
 108         for (final Entry<DOMDataTreeShard, Collection<DOMDataTreeIdentifier>> entry : shardToId.asMap().entrySet()) {
 109             if (entry.getKey() instanceof WriteableDOMDataTreeShard) {
 110                 //create a single producer for all prefixes in a single shard
 111                 final DOMDataTreeShardProducer producer = ((WriteableDOMDataTreeShard) entry.getKey())
 112                         .createProducer(entry.getValue());
 113                 // id mapped to producers
 114                 for (final DOMDataTreeIdentifier id : entry.getValue()) {
 115                     idToProducerBuilder.put(id, producer);
 116                 }
 117             } else {
 118                 LOG.error("Unable to create a producer for shard that's not a WriteableDOMDataTreeShard");
 119             }
 120         }
 121
 122         return idToProducerBuilder.build();
 123     }
 124
 125     @Override
 126     public synchronized DOMDataTreeCursorAwareTransaction createTransaction(final boolean isolated) {
 127         Preconditions.checkState(!closed, "Producer is already closed");
 128         Preconditions.checkState(openTx == null, "Transaction %s is still open", openTx);
 129
 130         LOG.debug("Creating transaction from producer");
 131         final ShardedDOMDataTreeWriteTransaction current = CURRENT_UPDATER.getAndSet(this, null);
 132         final ShardedDOMDataTreeWriteTransaction ret;
 133         if (isolated) {
 134             // Isolated case. If we have a previous transaction, submit it before returning this one.
 135             if (current != null) {
 136                 submitTransaction(current);
 137             }
 138             ret = new ShardedDOMDataTreeWriteTransaction(this, idToProducer, children, true);
 139         } else {
 140             // Non-isolated case, see if we can reuse the transaction
 141             if (current != null) {
 142                 LOG.debug("Reusing previous transaction {} since there is still a transaction inflight",
 143                         current.getIdentifier());
 144                 ret = current;
 145             } else {
 146                 ret = new ShardedDOMDataTreeWriteTransaction(this, idToProducer, children, false);
 147             }
 148         }
 149
 150         final boolean success = OPEN_UPDATER.compareAndSet(this, null, ret);
 151         Verify.verify(success);
 152         return ret;
 153     }
 154
 155     private void submitTransaction(final ShardedDOMDataTreeWriteTransaction current) {
 156         lastTx = current;
 157         current.doSubmit(this::transactionSuccessful, this::transactionFailed);
 158     }
 159
 160     @GuardedBy("this")
 161     private boolean haveSubtree(final DOMDataTreeIdentifier subtree) {
 162         for (final DOMDataTreeIdentifier i : idToShard.keySet()) {
 163             if (i.contains(subtree)) {
 164                 return true;
 165             }
 166         }
 167
 168         return false;
 169     }
 170
 171     @GuardedBy("this")
 172     private DOMDataTreeProducer lookupChild(final DOMDataTreeIdentifier domDataTreeIdentifier) {
 173         for (final Entry<DOMDataTreeIdentifier, DOMDataTreeProducer> e : children.entrySet()) {
 174             if (e.getKey().contains(domDataTreeIdentifier)) {
 175                 return e.getValue();
 176             }
 177         }
 178
 179         return null;
 180     }
 181
 182     @Override
 183     public synchronized DOMDataTreeProducer createProducer(final Collection<DOMDataTreeIdentifier> subtrees) {
 184         Preconditions.checkState(!closed, "Producer is already closed");
 185         Preconditions.checkState(openTx == null, "Transaction %s is still open", openTx);
 186
 187         for (final DOMDataTreeIdentifier s : subtrees) {
 188             // Check if the subtree was visible at any time
 189             Preconditions.checkArgument(haveSubtree(s), "Subtree %s was never available in producer %s", s, this);
 190             // Check if the subtree has not been delegated to a child
 191             final DOMDataTreeProducer child = lookupChild(s);
 192             Preconditions.checkArgument(child == null, "Subtree %s is delegated to child producer %s", s, child);
 193
 194             // Check if part of the requested subtree is not delegated to a child.
 195             for (final DOMDataTreeIdentifier c : children.keySet()) {
 196                 if (s.contains(c)) {
 197                     throw new IllegalArgumentException(String.format("Subtree %s cannot be delegated as it is"
 198                             + " superset of already-delegated %s", s, c));
 199                 }
 200             }
 201         }
 202
 203         final DOMDataTreeProducer ret = dataTree.createProducer(this, subtrees);
 204         final ImmutableMap.Builder<DOMDataTreeIdentifier, DOMDataTreeProducer> cb = ImmutableMap.builder();
 205         cb.putAll(children);
 206         for (final DOMDataTreeIdentifier s : subtrees) {
 207             cb.put(s, ret);
 208         }
 209
 210         children = cb.build();
 211         return ret;
 212     }
 213
 214     boolean isDelegatedToChild(final DOMDataTreeIdentifier path) {
 215         for (final DOMDataTreeIdentifier c : children.keySet()) {
 216             if (c.contains(path)) {
 217                 return true;
 218             }
 219         }
 220         return false;
 221     }
 222
 223
 224     @Override
 225     public synchronized void close() throws DOMDataTreeProducerException {
 226         if (!closed) {
 227             if (openTx != null) {
 228                 throw new DOMDataTreeProducerBusyException(String.format("Transaction %s is still open", openTx));
 229             }
 230
 231             closed = true;
 232             dataTree.destroyProducer(this);
 233         }
 234     }
 235
 236     protected Set<DOMDataTreeIdentifier> getSubtrees() {
 237         return subtrees;
 238     }
 239
 240     void cancelTransaction(final ShardedDOMDataTreeWriteTransaction transaction) {
 241         final boolean success = OPEN_UPDATER.compareAndSet(this, transaction, null);
 242         if (success) {
 243             LOG.debug("Transaction {} cancelled", transaction);
 244         } else {
 245             LOG.warn("Transaction {} is not open in producer {}", transaction, this);
 246         }
 247     }
 248
 249     void processTransaction(final ShardedDOMDataTreeWriteTransaction transaction) {
 250         final boolean wasOpen = OPEN_UPDATER.compareAndSet(this, transaction, null);
 251         Verify.verify(wasOpen);
 252
 253         if (lastTx != null) {
 254             final boolean success = CURRENT_UPDATER.compareAndSet(this, null, transaction);
 255             Verify.verify(success);
 256             if (lastTx == null) {
 257                 // Dispatch after requeue
 258                 processCurrentTransaction();
 259             }
 260         } else {
 261             submitTransaction(transaction);
 262         }
 263     }
 264
 265     void transactionSuccessful(final ShardedDOMDataTreeWriteTransaction tx, final Void result) {
 266         LOG.debug("Transaction {} completed successfully", tx.getIdentifier());
 267
 268         tx.onTransactionSuccess(result);
 269         processNextTransaction(tx);
 270     }
 271
 272     void transactionFailed(final ShardedDOMDataTreeWriteTransaction tx, final Throwable throwable) {
 273         LOG.debug("Transaction {} failed", tx.getIdentifier(), throwable);
 274
 275         tx.onTransactionFailure(throwable);
 276         processNextTransaction(tx);
 277     }
 278
 279     private void processCurrentTransaction() {
 280         final ShardedDOMDataTreeWriteTransaction current = CURRENT_UPDATER.getAndSet(this, null);
 281         if (current != null) {
 282             submitTransaction(current);
 283         }
 284     }
 285
 286     private void processNextTransaction(final ShardedDOMDataTreeWriteTransaction tx) {
 287         final boolean wasLast = LAST_UPDATER.compareAndSet(this, tx, null);
 288         if (wasLast) {
 289             processCurrentTransaction();
 290         }
 291     }
 292
 293     synchronized void boundToListener(final ShardedDOMDataTreeListenerContext<?> listener) {
 294         // FIXME: Add option to detach
 295         Preconditions.checkState(this.attachedListener == null, "Producer %s is already attached to other listener.",
 296                 listener.getListener());
 297         this.attachedListener = listener;
 298     }
 299 }