alshabib | ab98466 | 2014-12-04 18:56:18 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2014 Open Networking Laboratory |
| 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 | */ |
Brian O'Connor | abafb50 | 2014-12-02 22:26:20 -0800 | [diff] [blame] | 16 | package org.onosproject.store.service.impl; |
Madan Jampani | 12390c1 | 2014-11-12 00:35:56 -0800 | [diff] [blame] | 17 | |
Madan Jampani | 1ee9178 | 2014-11-20 20:24:24 -0800 | [diff] [blame] | 18 | import static com.google.common.base.Verify.verify; |
Madan Jampani | a88d1f5 | 2014-11-14 16:45:24 -0800 | [diff] [blame] | 19 | import static org.slf4j.LoggerFactory.getLogger; |
| 20 | |
Ray Milkey | 241b96a | 2014-11-17 13:08:20 -0800 | [diff] [blame] | 21 | import java.nio.charset.StandardCharsets; |
Madan Jampani | 1ee9178 | 2014-11-20 20:24:24 -0800 | [diff] [blame] | 22 | import java.util.Arrays; |
Madan Jampani | 12390c1 | 2014-11-12 00:35:56 -0800 | [diff] [blame] | 23 | import java.util.UUID; |
| 24 | import java.util.concurrent.CompletableFuture; |
| 25 | import java.util.concurrent.ExecutionException; |
| 26 | import java.util.concurrent.TimeUnit; |
| 27 | import java.util.concurrent.TimeoutException; |
| 28 | import java.util.concurrent.atomic.AtomicBoolean; |
| 29 | |
| 30 | import org.joda.time.DateTime; |
Brian O'Connor | abafb50 | 2014-12-02 22:26:20 -0800 | [diff] [blame] | 31 | import org.onosproject.cluster.ClusterService; |
| 32 | import org.onosproject.store.service.DatabaseException; |
| 33 | import org.onosproject.store.service.DatabaseService; |
| 34 | import org.onosproject.store.service.Lock; |
| 35 | import org.onosproject.store.service.VersionedValue; |
Madan Jampani | a88d1f5 | 2014-11-14 16:45:24 -0800 | [diff] [blame] | 36 | import org.slf4j.Logger; |
Madan Jampani | 12390c1 | 2014-11-12 00:35:56 -0800 | [diff] [blame] | 37 | |
| 38 | /** |
| 39 | * A distributed lock implementation. |
| 40 | */ |
| 41 | public class DistributedLock implements Lock { |
| 42 | |
Madan Jampani | a88d1f5 | 2014-11-14 16:45:24 -0800 | [diff] [blame] | 43 | private final Logger log = getLogger(getClass()); |
| 44 | |
Madan Jampani | 12390c1 | 2014-11-12 00:35:56 -0800 | [diff] [blame] | 45 | private final DistributedLockManager lockManager; |
| 46 | private final DatabaseService databaseService; |
| 47 | private final String path; |
| 48 | private DateTime lockExpirationTime; |
| 49 | private AtomicBoolean isLocked = new AtomicBoolean(false); |
Madan Jampani | 1ee9178 | 2014-11-20 20:24:24 -0800 | [diff] [blame] | 50 | private volatile long epoch = 0; |
Madan Jampani | 12390c1 | 2014-11-12 00:35:56 -0800 | [diff] [blame] | 51 | private byte[] lockId; |
| 52 | |
| 53 | public DistributedLock( |
| 54 | String path, |
| 55 | DatabaseService databaseService, |
| 56 | ClusterService clusterService, |
| 57 | DistributedLockManager lockManager) { |
| 58 | |
| 59 | this.path = path; |
| 60 | this.databaseService = databaseService; |
| 61 | this.lockManager = lockManager; |
| 62 | this.lockId = |
Ray Milkey | 241b96a | 2014-11-17 13:08:20 -0800 | [diff] [blame] | 63 | (UUID.randomUUID().toString() + "::" + |
| 64 | clusterService.getLocalNode().id().toString()). |
| 65 | getBytes(StandardCharsets.UTF_8); |
Madan Jampani | 12390c1 | 2014-11-12 00:35:56 -0800 | [diff] [blame] | 66 | } |
| 67 | |
| 68 | @Override |
| 69 | public String path() { |
| 70 | return path; |
| 71 | } |
| 72 | |
| 73 | @Override |
Madan Jampani | 71582ed | 2014-11-18 10:06:01 -0800 | [diff] [blame] | 74 | public void lock(int leaseDurationMillis) throws InterruptedException { |
Madan Jampani | 1769a1a | 2014-11-19 21:51:44 -0800 | [diff] [blame] | 75 | try { |
| 76 | lockAsync(leaseDurationMillis).get(); |
| 77 | } catch (ExecutionException e) { |
| 78 | throw new DatabaseException(e); |
Madan Jampani | 12390c1 | 2014-11-12 00:35:56 -0800 | [diff] [blame] | 79 | } |
| 80 | } |
| 81 | |
| 82 | @Override |
Madan Jampani | 1d3494e | 2014-11-20 11:24:22 -0800 | [diff] [blame] | 83 | public CompletableFuture<Void> lockAsync(int leaseDurationMillis) { |
Madan Jampani | ddaffd0 | 2014-11-21 13:12:09 -0800 | [diff] [blame] | 84 | try { |
| 85 | if (isLocked() || tryLock(leaseDurationMillis)) { |
| 86 | return CompletableFuture.<Void>completedFuture(null); |
| 87 | } |
| 88 | return lockManager.lockIfAvailable(this, leaseDurationMillis); |
| 89 | } catch (DatabaseException e) { |
| 90 | CompletableFuture<Void> lockFuture = new CompletableFuture<>(); |
| 91 | lockFuture.completeExceptionally(e); |
| 92 | return lockFuture; |
Madan Jampani | 1769a1a | 2014-11-19 21:51:44 -0800 | [diff] [blame] | 93 | } |
Madan Jampani | 1769a1a | 2014-11-19 21:51:44 -0800 | [diff] [blame] | 94 | } |
| 95 | |
| 96 | @Override |
Madan Jampani | 12390c1 | 2014-11-12 00:35:56 -0800 | [diff] [blame] | 97 | public boolean tryLock(int leaseDurationMillis) { |
Madan Jampani | a88d1f5 | 2014-11-14 16:45:24 -0800 | [diff] [blame] | 98 | if (databaseService.putIfAbsent( |
Madan Jampani | c22123d | 2014-11-12 02:12:19 -0800 | [diff] [blame] | 99 | DistributedLockManager.ONOS_LOCK_TABLE_NAME, |
| 100 | path, |
Madan Jampani | a88d1f5 | 2014-11-14 16:45:24 -0800 | [diff] [blame] | 101 | lockId)) { |
Madan Jampani | 1ee9178 | 2014-11-20 20:24:24 -0800 | [diff] [blame] | 102 | VersionedValue vv = |
| 103 | databaseService.get(DistributedLockManager.ONOS_LOCK_TABLE_NAME, path); |
| 104 | verify(Arrays.equals(vv.value(), lockId)); |
| 105 | epoch = vv.version(); |
Madan Jampani | a88d1f5 | 2014-11-14 16:45:24 -0800 | [diff] [blame] | 106 | isLocked.set(true); |
| 107 | lockExpirationTime = DateTime.now().plusMillis(leaseDurationMillis); |
| 108 | return true; |
| 109 | } |
| 110 | return false; |
Madan Jampani | 12390c1 | 2014-11-12 00:35:56 -0800 | [diff] [blame] | 111 | } |
| 112 | |
| 113 | @Override |
| 114 | public boolean tryLock( |
Madan Jampani | 1769a1a | 2014-11-19 21:51:44 -0800 | [diff] [blame] | 115 | int waitTimeMillis, |
Madan Jampani | 71582ed | 2014-11-18 10:06:01 -0800 | [diff] [blame] | 116 | int leaseDurationMillis) throws InterruptedException { |
Madan Jampani | 1769a1a | 2014-11-19 21:51:44 -0800 | [diff] [blame] | 117 | if (isLocked() || tryLock(leaseDurationMillis)) { |
Madan Jampani | a88d1f5 | 2014-11-14 16:45:24 -0800 | [diff] [blame] | 118 | return true; |
Madan Jampani | 12390c1 | 2014-11-12 00:35:56 -0800 | [diff] [blame] | 119 | } |
Madan Jampani | 1769a1a | 2014-11-19 21:51:44 -0800 | [diff] [blame] | 120 | |
| 121 | CompletableFuture<Void> future = |
Madan Jampani | a88d1f5 | 2014-11-14 16:45:24 -0800 | [diff] [blame] | 122 | lockManager.lockIfAvailable(this, waitTimeMillis, leaseDurationMillis); |
| 123 | try { |
Madan Jampani | 1769a1a | 2014-11-19 21:51:44 -0800 | [diff] [blame] | 124 | future.get(waitTimeMillis, TimeUnit.MILLISECONDS); |
Madan Jampani | a88d1f5 | 2014-11-14 16:45:24 -0800 | [diff] [blame] | 125 | return true; |
Madan Jampani | 71582ed | 2014-11-18 10:06:01 -0800 | [diff] [blame] | 126 | } catch (ExecutionException e) { |
| 127 | throw new DatabaseException(e); |
Madan Jampani | a88d1f5 | 2014-11-14 16:45:24 -0800 | [diff] [blame] | 128 | } catch (TimeoutException e) { |
| 129 | log.debug("Timed out waiting to acquire lock for {}", path); |
| 130 | return false; |
| 131 | } |
Madan Jampani | 12390c1 | 2014-11-12 00:35:56 -0800 | [diff] [blame] | 132 | } |
| 133 | |
| 134 | @Override |
| 135 | public boolean isLocked() { |
| 136 | if (isLocked.get()) { |
| 137 | // We rely on local information to check |
Madan Jampani | a88d1f5 | 2014-11-14 16:45:24 -0800 | [diff] [blame] | 138 | // if the lock expired. |
Madan Jampani | 12390c1 | 2014-11-12 00:35:56 -0800 | [diff] [blame] | 139 | // This should should make this call |
Madan Jampani | a88d1f5 | 2014-11-14 16:45:24 -0800 | [diff] [blame] | 140 | // light weight, while still retaining the |
Madan Jampani | 12390c1 | 2014-11-12 00:35:56 -0800 | [diff] [blame] | 141 | // safety guarantees. |
| 142 | if (DateTime.now().isAfter(lockExpirationTime)) { |
| 143 | isLocked.set(false); |
| 144 | return false; |
Madan Jampani | f5d263b | 2014-11-13 10:04:40 -0800 | [diff] [blame] | 145 | } else { |
| 146 | return true; |
Madan Jampani | 12390c1 | 2014-11-12 00:35:56 -0800 | [diff] [blame] | 147 | } |
| 148 | } |
Madan Jampani | f5d263b | 2014-11-13 10:04:40 -0800 | [diff] [blame] | 149 | return false; |
Madan Jampani | 12390c1 | 2014-11-12 00:35:56 -0800 | [diff] [blame] | 150 | } |
| 151 | |
| 152 | @Override |
Madan Jampani | 1ee9178 | 2014-11-20 20:24:24 -0800 | [diff] [blame] | 153 | public long epoch() { |
| 154 | return epoch; |
| 155 | } |
| 156 | |
| 157 | @Override |
Madan Jampani | 12390c1 | 2014-11-12 00:35:56 -0800 | [diff] [blame] | 158 | public void unlock() { |
| 159 | if (!isLocked()) { |
| 160 | return; |
| 161 | } else { |
Madan Jampani | a88d1f5 | 2014-11-14 16:45:24 -0800 | [diff] [blame] | 162 | if (databaseService.removeIfValueMatches(DistributedLockManager.ONOS_LOCK_TABLE_NAME, path, lockId)) { |
| 163 | isLocked.set(false); |
| 164 | } |
Madan Jampani | 12390c1 | 2014-11-12 00:35:56 -0800 | [diff] [blame] | 165 | } |
| 166 | } |
| 167 | |
| 168 | @Override |
| 169 | public boolean extendExpiration(int leaseDurationMillis) { |
Madan Jampani | a88d1f5 | 2014-11-14 16:45:24 -0800 | [diff] [blame] | 170 | if (!isLocked()) { |
| 171 | log.warn("Ignoring request to extend expiration for lock {}." |
| 172 | + " ExtendExpiration must be called for locks that are already acquired.", path); |
Pavlin Radoslavov | 20ded69 | 2014-11-17 16:03:15 -0800 | [diff] [blame] | 173 | return false; |
Madan Jampani | a88d1f5 | 2014-11-14 16:45:24 -0800 | [diff] [blame] | 174 | } |
| 175 | |
| 176 | if (databaseService.putIfValueMatches( |
| 177 | DistributedLockManager.ONOS_LOCK_TABLE_NAME, |
| 178 | path, |
| 179 | lockId, |
| 180 | lockId)) { |
| 181 | lockExpirationTime = DateTime.now().plusMillis(leaseDurationMillis); |
| 182 | log.debug("Succeeded in extending lock {} expiration time to {}", lockExpirationTime); |
Madan Jampani | 12390c1 | 2014-11-12 00:35:56 -0800 | [diff] [blame] | 183 | return true; |
| 184 | } else { |
Madan Jampani | a88d1f5 | 2014-11-14 16:45:24 -0800 | [diff] [blame] | 185 | log.info("Failed to extend expiration for {}", path); |
| 186 | return false; |
Madan Jampani | 12390c1 | 2014-11-12 00:35:56 -0800 | [diff] [blame] | 187 | } |
| 188 | } |
Madan Jampani | a88d1f5 | 2014-11-14 16:45:24 -0800 | [diff] [blame] | 189 | } |