2 * Copyright (c) 2016 Cisco Systems, Inc. and others. All rights reserved.
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
8 package org.opendaylight.controller.cluster.databroker.actors.dds;
10 import com.google.common.base.Preconditions;
11 import com.google.common.base.Verify;
12 import java.util.HashMap;
14 import java.util.concurrent.ConcurrentHashMap;
15 import java.util.concurrent.atomic.AtomicLongFieldUpdater;
16 import java.util.concurrent.atomic.AtomicReferenceFieldUpdater;
17 import java.util.concurrent.locks.StampedLock;
18 import javax.annotation.concurrent.GuardedBy;
19 import org.opendaylight.controller.cluster.access.client.AbstractClientConnection;
20 import org.opendaylight.controller.cluster.access.client.ConnectedClientConnection;
21 import org.opendaylight.controller.cluster.access.client.ConnectionEntry;
22 import org.opendaylight.controller.cluster.access.client.InversibleLockException;
23 import org.opendaylight.controller.cluster.access.commands.CreateLocalHistoryRequest;
24 import org.opendaylight.controller.cluster.access.concepts.LocalHistoryIdentifier;
25 import org.opendaylight.controller.cluster.access.concepts.Response;
26 import org.opendaylight.controller.cluster.access.concepts.TransactionIdentifier;
27 import org.opendaylight.mdsal.common.api.TransactionChainClosedException;
28 import org.opendaylight.yangtools.concepts.Identifiable;
29 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
30 import org.slf4j.Logger;
31 import org.slf4j.LoggerFactory;
34 * Abstract base class for client view of a history. This class has two implementations, one for normal local histories
35 * and the other for single transactions.
37 * @author Robert Varga
39 public abstract class AbstractClientHistory extends LocalAbortable implements Identifiable<LocalHistoryIdentifier> {
46 private static final Logger LOG = LoggerFactory.getLogger(AbstractClientHistory.class);
47 private static final AtomicLongFieldUpdater<AbstractClientHistory> NEXT_TX_UPDATER =
48 AtomicLongFieldUpdater.newUpdater(AbstractClientHistory.class, "nextTx");
49 private static final AtomicReferenceFieldUpdater<AbstractClientHistory, State> STATE_UPDATER =
50 AtomicReferenceFieldUpdater.newUpdater(AbstractClientHistory.class, State.class, "state");
53 private final Map<TransactionIdentifier, AbstractClientHandle<?>> openTransactions = new HashMap<>();
55 private final Map<TransactionIdentifier, AbstractTransactionCommitCohort> readyTransactions = new HashMap<>();
58 private final Map<Long, ProxyHistory> histories = new ConcurrentHashMap<>();
59 private final StampedLock lock = new StampedLock();
61 private final AbstractDataStoreClientBehavior client;
62 private final LocalHistoryIdentifier identifier;
64 // Used via NEXT_TX_UPDATER
65 @SuppressWarnings("unused")
66 private volatile long nextTx = 0;
68 private volatile State state = State.IDLE;
70 AbstractClientHistory(final AbstractDataStoreClientBehavior client, final LocalHistoryIdentifier identifier) {
71 this.client = Preconditions.checkNotNull(client);
72 this.identifier = Preconditions.checkNotNull(identifier);
73 Preconditions.checkArgument(identifier.getCookie() == 0);
80 final void updateState(final State expected, final State next) {
81 final boolean success = STATE_UPDATER.compareAndSet(this, expected, next);
82 Preconditions.checkState(success, "Race condition detected, state changed from %s to %s", expected, state);
83 LOG.debug("Client history {} changed state from {} to {}", this, expected, next);
86 final synchronized void doClose() {
87 final State local = state;
88 if (local != State.CLOSED) {
89 Preconditions.checkState(local == State.IDLE, "Local history %s has an open transaction", this);
90 histories.values().forEach(ProxyHistory::close);
91 updateState(local, State.CLOSED);
95 final synchronized void onProxyDestroyed(final ProxyHistory proxyHistory) {
96 histories.remove(proxyHistory.getIdentifier().getCookie());
97 LOG.debug("{}: removed destroyed proxy {}", this, proxyHistory);
101 public LocalHistoryIdentifier getIdentifier() {
105 final long nextTx() {
106 return NEXT_TX_UPDATER.getAndIncrement(this);
109 final Long resolveShardForPath(final YangInstanceIdentifier path) {
110 return client.resolveShardForPath(path);
114 final void localAbort(final Throwable cause) {
115 final State oldState = STATE_UPDATER.getAndSet(this, State.CLOSED);
116 if (oldState != State.CLOSED) {
117 LOG.debug("Force-closing history {}", getIdentifier(), cause);
119 synchronized (this) {
120 for (AbstractClientHandle<?> t : openTransactions.values()) {
123 openTransactions.clear();
124 readyTransactions.clear();
130 * Create a new history proxy for a given shard.
132 * @throws InversibleLockException if the shard is being reconnected
135 private ProxyHistory createHistoryProxy(final Long shard) {
136 final AbstractClientConnection<ShardBackendInfo> connection = client.getConnection(shard);
137 final LocalHistoryIdentifier proxyId = new LocalHistoryIdentifier(identifier.getClientId(),
138 identifier.getHistoryId(), shard);
139 LOG.debug("Created proxyId {} for history {} shard {}", proxyId, identifier, shard);
141 final ProxyHistory ret = createHistoryProxy(proxyId, connection);
143 // Request creation of the history, if it is not the single history
144 if (ret.getIdentifier().getHistoryId() != 0) {
145 connection.sendRequest(new CreateLocalHistoryRequest(ret.getIdentifier(), connection.localActor()),
146 this::createHistoryCallback);
151 abstract ProxyHistory createHistoryProxy(LocalHistoryIdentifier historyId,
152 AbstractClientConnection<ShardBackendInfo> connection);
154 private void createHistoryCallback(final Response<?, ?> response) {
155 LOG.debug("Create history response {}", response);
158 private ProxyHistory ensureHistoryProxy(final TransactionIdentifier transactionId, final Long shard) {
161 // Short-lived lock to ensure exclusion of createHistoryProxy and the lookup phase in startReconnect,
162 // see comments in startReconnect() for details.
163 final long stamp = lock.readLock();
165 return histories.computeIfAbsent(shard, this::createHistoryProxy);
167 lock.unlockRead(stamp);
169 } catch (InversibleLockException e) {
170 LOG.trace("Waiting for transaction {} shard {} connection to resolve", transactionId, shard);
172 LOG.trace("Retrying transaction {} shard {} connection", transactionId, shard);
177 final AbstractProxyTransaction createSnapshotProxy(final TransactionIdentifier transactionId, final Long shard) {
178 return ensureHistoryProxy(transactionId, shard).createTransactionProxy(transactionId, true);
181 final AbstractProxyTransaction createTransactionProxy(final TransactionIdentifier transactionId, final Long shard) {
182 return ensureHistoryProxy(transactionId, shard).createTransactionProxy(transactionId, false);
185 private void checkNotClosed() {
186 if (state == State.CLOSED) {
187 throw new TransactionChainClosedException(String.format("Local history %s is closed", identifier));
192 * Allocate a new {@link ClientTransaction}.
194 * @return A new {@link ClientTransaction}
195 * @throws TransactionChainClosedException if this history is closed
196 * @throws IllegalStateException if a previous dependent transaction has not been closed
198 public ClientTransaction createTransaction() {
201 synchronized (this) {
202 final ClientTransaction ret = doCreateTransaction();
203 openTransactions.put(ret.getIdentifier(), ret);
209 * Create a new {@link ClientSnapshot}.
211 * @return A new {@link ClientSnapshot}
212 * @throws TransactionChainClosedException if this history is closed
213 * @throws IllegalStateException if a previous dependent transaction has not been closed
215 public ClientSnapshot takeSnapshot() {
218 synchronized (this) {
219 final ClientSnapshot ret = doCreateSnapshot();
220 openTransactions.put(ret.getIdentifier(), ret);
226 abstract ClientSnapshot doCreateSnapshot();
229 abstract ClientTransaction doCreateTransaction();
232 * Callback invoked from {@link ClientTransaction} when a child transaction readied for submission.
234 * @param txId Transaction identifier
235 * @param cohort Transaction commit cohort
237 synchronized AbstractTransactionCommitCohort onTransactionReady(final ClientTransaction tx,
238 final AbstractTransactionCommitCohort cohort) {
239 final TransactionIdentifier txId = tx.getIdentifier();
240 if (openTransactions.remove(txId) == null) {
241 LOG.warn("Transaction {} not recorded, proceeding with readiness", txId);
244 final AbstractTransactionCommitCohort previous = readyTransactions.putIfAbsent(txId, cohort);
245 Preconditions.checkState(previous == null, "Duplicate cohort %s for transaction %s, already have %s",
246 cohort, txId, previous);
248 LOG.debug("Local history {} readied transaction {}", this, txId);
253 * Callback invoked from {@link ClientTransaction} when a child transaction has been aborted without touching
256 * @param snapshot transaction identifier
258 synchronized void onTransactionAbort(final AbstractClientHandle<?> snapshot) {
259 if (openTransactions.remove(snapshot.getIdentifier()) == null) {
260 LOG.warn("Could not find aborting transaction {}", snapshot.getIdentifier());
265 * Callback invoked from {@link AbstractTransactionCommitCohort} when a child transaction has been completed
266 * and all its state can be removed.
268 * @param txId transaction identifier
270 synchronized void onTransactionComplete(final TransactionIdentifier txId) {
271 if (readyTransactions.remove(txId) == null) {
272 LOG.warn("Could not find completed transaction {}", txId);
276 HistoryReconnectCohort startReconnect(final ConnectedClientConnection<ShardBackendInfo> newConn) {
278 * This looks ugly and unusual and there is a reason for that, as the locking involved is in multiple places.
280 * We need to make sure that a new proxy is not created while we are reconnecting, which is partially satisfied
281 * by client.getConnection() throwing InversibleLockException by the time this method is invoked. That does
282 * not cover the case when createHistoryProxy() has already acquired the connection, but has not yet populated
285 * Hence we need to make sure no potential computation is happening concurrently with us looking at the history
286 * map. Once we have performed that lookup, though, we can release the lock immediately, as all creation
287 * requests are established to happen either before or after the reconnect attempt.
289 final ProxyHistory oldProxy;
290 final long stamp = lock.writeLock();
292 oldProxy = histories.get(newConn.cookie());
294 lock.unlockWrite(stamp);
297 if (oldProxy == null) {
301 final ProxyReconnectCohort proxy = Verify.verifyNotNull(oldProxy.startReconnect(newConn));
302 return new HistoryReconnectCohort() {
304 ProxyReconnectCohort getProxy() {
309 void replayRequests(final Iterable<ConnectionEntry> previousEntries) {
310 proxy.replayRequests(previousEntries);
314 public void close() {
315 LOG.debug("Client history {} finishing reconnect to {}", AbstractClientHistory.this, newConn);
316 final ProxyHistory newProxy = proxy.finishReconnect();
317 if (!histories.replace(newConn.cookie(), oldProxy, newProxy)) {
318 LOG.warn("Failed to replace proxy {} with {} in {}", oldProxy, newProxy,
319 AbstractClientHistory.this);