Jordan Halterman | a76f231 | 2018-01-25 16:56:45 -0800 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 2018-present Open Networking Foundation |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | package org.onosproject.store.primitives.resources.impl; |
| 17 | |
| 18 | import java.time.Duration; |
| 19 | import java.util.ArrayDeque; |
| 20 | import java.util.HashMap; |
| 21 | import java.util.Map; |
| 22 | import java.util.Queue; |
| 23 | |
| 24 | import io.atomix.protocols.raft.service.AbstractRaftService; |
| 25 | import io.atomix.protocols.raft.service.Commit; |
| 26 | import io.atomix.protocols.raft.service.RaftServiceExecutor; |
| 27 | import io.atomix.protocols.raft.session.RaftSession; |
| 28 | import io.atomix.protocols.raft.storage.snapshot.SnapshotReader; |
| 29 | import io.atomix.protocols.raft.storage.snapshot.SnapshotWriter; |
| 30 | import io.atomix.utils.concurrent.Scheduled; |
| 31 | import org.onlab.util.KryoNamespace; |
| 32 | import org.onosproject.store.serializers.KryoNamespaces; |
| 33 | import org.onosproject.store.service.Serializer; |
| 34 | |
| 35 | import static com.google.common.base.MoreObjects.toStringHelper; |
| 36 | import static org.onosproject.store.primitives.resources.impl.AtomixDistributedLockEvents.FAIL; |
| 37 | import static org.onosproject.store.primitives.resources.impl.AtomixDistributedLockOperations.LOCK; |
| 38 | import static org.onosproject.store.primitives.resources.impl.AtomixDistributedLockOperations.Lock; |
| 39 | import static org.onosproject.store.primitives.resources.impl.AtomixDistributedLockOperations.UNLOCK; |
| 40 | import static org.onosproject.store.primitives.resources.impl.AtomixDistributedLockOperations.Unlock; |
| 41 | |
| 42 | /** |
| 43 | * Raft atomic value service. |
| 44 | */ |
| 45 | public class AtomixDistributedLockService extends AbstractRaftService { |
| 46 | private static final Serializer SERIALIZER = Serializer.using(KryoNamespace.newBuilder() |
| 47 | .register(KryoNamespaces.BASIC) |
| 48 | .register(AtomixDistributedLockOperations.NAMESPACE) |
| 49 | .register(AtomixDistributedLockEvents.NAMESPACE) |
| 50 | .register(LockHolder.class) |
| 51 | .register(ArrayDeque.class) |
| 52 | .build()); |
| 53 | |
| 54 | private LockHolder lock; |
| 55 | private Queue<LockHolder> queue = new ArrayDeque<>(); |
| 56 | private final Map<Long, Scheduled> timers = new HashMap<>(); |
| 57 | |
| 58 | @Override |
| 59 | protected void configure(RaftServiceExecutor executor) { |
| 60 | executor.register(LOCK, SERIALIZER::decode, this::lock); |
| 61 | executor.register(UNLOCK, SERIALIZER::decode, this::unlock); |
| 62 | } |
| 63 | |
| 64 | @Override |
| 65 | public void snapshot(SnapshotWriter writer) { |
| 66 | writer.writeObject(lock, SERIALIZER::encode); |
| 67 | writer.writeObject(queue, SERIALIZER::encode); |
| 68 | } |
| 69 | |
| 70 | @Override |
| 71 | public void install(SnapshotReader reader) { |
| 72 | lock = reader.readObject(SERIALIZER::decode); |
| 73 | queue = reader.readObject(SERIALIZER::decode); |
| 74 | timers.values().forEach(Scheduled::cancel); |
| 75 | timers.clear(); |
| 76 | for (LockHolder holder : queue) { |
| 77 | if (holder.expire > 0) { |
| 78 | timers.put(holder.index, |
| 79 | scheduler().schedule(Duration.ofMillis(holder.expire - wallClock().getTime().unixTimestamp()), |
| 80 | () -> { |
| 81 | timers.remove(holder.index); |
| 82 | queue.remove(holder); |
| 83 | RaftSession session = sessions().getSession(holder.session); |
| 84 | if (session != null && session.getState().active()) { |
| 85 | session.publish(FAIL, SERIALIZER::encode, new LockEvent(holder.id, holder.index)); |
| 86 | } |
| 87 | })); |
| 88 | } |
| 89 | } |
| 90 | } |
| 91 | |
| 92 | @Override |
| 93 | public void onExpire(RaftSession session) { |
| 94 | releaseSession(session); |
| 95 | } |
| 96 | |
| 97 | @Override |
| 98 | public void onClose(RaftSession session) { |
| 99 | releaseSession(session); |
| 100 | } |
| 101 | |
| 102 | /** |
| 103 | * Applies a lock commit. |
| 104 | * |
| 105 | * @param commit the lock commit |
| 106 | */ |
| 107 | protected void lock(Commit<Lock> commit) { |
| 108 | if (lock == null) { |
| 109 | lock = new LockHolder( |
| 110 | commit.value().id(), |
| 111 | commit.index(), |
| 112 | commit.session().sessionId().id(), |
| 113 | 0); |
| 114 | commit.session().publish( |
| 115 | AtomixDistributedLockEvents.LOCK, |
| 116 | SERIALIZER::encode, |
| 117 | new LockEvent(commit.value().id(), commit.index())); |
| 118 | } else if (commit.value().timeout() == 0) { |
| 119 | commit.session().publish(FAIL, SERIALIZER::encode, new LockEvent(commit.value().id(), commit.index())); |
| 120 | } else if (commit.value().timeout() > 0) { |
| 121 | LockHolder holder = new LockHolder( |
| 122 | commit.value().id(), |
| 123 | commit.index(), |
| 124 | commit.session().sessionId().id(), |
| 125 | wallClock().getTime().unixTimestamp() + commit.value().timeout()); |
| 126 | queue.add(holder); |
| 127 | timers.put(commit.index(), scheduler().schedule(Duration.ofMillis(commit.value().timeout()), () -> { |
| 128 | timers.remove(commit.index()); |
| 129 | queue.remove(holder); |
| 130 | if (commit.session().getState().active()) { |
| 131 | commit.session().publish( |
| 132 | FAIL, |
| 133 | SERIALIZER::encode, |
| 134 | new LockEvent(commit.value().id(), commit.index())); |
| 135 | } |
| 136 | })); |
| 137 | } else { |
| 138 | LockHolder holder = new LockHolder( |
| 139 | commit.value().id(), |
| 140 | commit.index(), |
| 141 | commit.session().sessionId().id(), |
| 142 | 0); |
| 143 | queue.add(holder); |
| 144 | } |
| 145 | } |
| 146 | |
| 147 | /** |
| 148 | * Applies an unlock commit. |
| 149 | * |
| 150 | * @param commit the unlock commit |
| 151 | */ |
| 152 | protected void unlock(Commit<Unlock> commit) { |
| 153 | if (lock != null) { |
| 154 | if (lock.session != commit.session().sessionId().id()) { |
| 155 | return; |
| 156 | } |
| 157 | |
| 158 | lock = queue.poll(); |
| 159 | while (lock != null) { |
| 160 | Scheduled timer = timers.remove(lock.index); |
| 161 | if (timer != null) { |
| 162 | timer.cancel(); |
| 163 | } |
| 164 | |
| 165 | RaftSession session = sessions().getSession(lock.session); |
| 166 | if (session == null || session.getState() == RaftSession.State.EXPIRED |
| 167 | || session.getState() == RaftSession.State.CLOSED) { |
| 168 | lock = queue.poll(); |
| 169 | } else { |
| 170 | session.publish( |
| 171 | AtomixDistributedLockEvents.LOCK, |
| 172 | SERIALIZER::encode, |
| 173 | new LockEvent(lock.id, commit.index())); |
| 174 | break; |
| 175 | } |
| 176 | } |
| 177 | } |
| 178 | } |
| 179 | |
| 180 | private void releaseSession(RaftSession session) { |
| 181 | if (lock != null && lock.session == session.sessionId().id()) { |
| 182 | lock = queue.poll(); |
| 183 | while (lock != null) { |
| 184 | if (lock.session == session.sessionId().id()) { |
| 185 | lock = queue.poll(); |
| 186 | } else { |
| 187 | Scheduled timer = timers.remove(lock.index); |
| 188 | if (timer != null) { |
| 189 | timer.cancel(); |
| 190 | } |
| 191 | |
| 192 | RaftSession lockSession = sessions().getSession(lock.session); |
| 193 | if (lockSession == null || lockSession.getState() == RaftSession.State.EXPIRED |
| 194 | || lockSession.getState() == RaftSession.State.CLOSED) { |
| 195 | lock = queue.poll(); |
| 196 | } else { |
| 197 | lockSession.publish( |
| 198 | AtomixDistributedLockEvents.LOCK, |
| 199 | SERIALIZER::encode, |
| 200 | new LockEvent(lock.id, lock.index)); |
| 201 | break; |
| 202 | } |
| 203 | } |
| 204 | } |
| 205 | } |
| 206 | } |
| 207 | |
| 208 | private class LockHolder { |
| 209 | private final int id; |
| 210 | private final long index; |
| 211 | private final long session; |
| 212 | private final long expire; |
| 213 | |
| 214 | public LockHolder(int id, long index, long session, long expire) { |
| 215 | this.id = id; |
| 216 | this.index = index; |
| 217 | this.session = session; |
| 218 | this.expire = expire; |
| 219 | } |
| 220 | |
| 221 | @Override |
| 222 | public String toString() { |
| 223 | return toStringHelper(this) |
| 224 | .add("id", id) |
| 225 | .add("index", index) |
| 226 | .add("session", session) |
| 227 | .add("expire", expire) |
| 228 | .toString(); |
| 229 | } |
| 230 | } |
| 231 | } |