Pavlin Radoslavov | a071b1e | 2014-11-17 13:37:57 -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 | */ |
| 16 | package org.onlab.onos.sdnip; |
| 17 | |
| 18 | import java.util.Collection; |
| 19 | import java.util.HashMap; |
| 20 | import java.util.LinkedList; |
| 21 | import java.util.List; |
| 22 | import java.util.Map; |
| 23 | import java.util.concurrent.ConcurrentHashMap; |
| 24 | import java.util.concurrent.ExecutorService; |
| 25 | import java.util.concurrent.Executors; |
| 26 | import java.util.concurrent.Semaphore; |
| 27 | |
| 28 | import org.apache.commons.lang3.tuple.Pair; |
| 29 | import org.onlab.onos.core.ApplicationId; |
| 30 | import org.onlab.onos.net.flow.criteria.Criteria.IPCriterion; |
| 31 | import org.onlab.onos.net.flow.criteria.Criterion; |
| 32 | import org.onlab.onos.net.intent.Intent; |
| 33 | import org.onlab.onos.net.intent.IntentService; |
| 34 | import org.onlab.onos.net.intent.IntentState; |
| 35 | import org.onlab.onos.net.intent.MultiPointToSinglePointIntent; |
| 36 | import org.onlab.packet.Ip4Prefix; |
| 37 | import org.slf4j.Logger; |
| 38 | import org.slf4j.LoggerFactory; |
| 39 | |
| 40 | import com.google.common.base.Objects; |
| 41 | import com.google.common.util.concurrent.ThreadFactoryBuilder; |
| 42 | |
| 43 | public class IntentSynchronizer { |
| 44 | private static final Logger log = |
| 45 | LoggerFactory.getLogger(IntentSynchronizer.class); |
| 46 | |
| 47 | private final ApplicationId appId; |
| 48 | private final IntentService intentService; |
| 49 | private final Map<Ip4Prefix, MultiPointToSinglePointIntent> pushedRouteIntents; |
| 50 | |
| 51 | // |
| 52 | // State to deal with SDN-IP Leader election and pushing Intents |
| 53 | // |
| 54 | private final ExecutorService bgpIntentsSynchronizerExecutor; |
| 55 | private final Semaphore intentsSynchronizerSemaphore = new Semaphore(0); |
| 56 | private volatile boolean isElectedLeader = false; |
| 57 | private volatile boolean isActivatedLeader = false; |
| 58 | |
| 59 | /** |
| 60 | * Class constructor. |
| 61 | * |
| 62 | * @param appId the Application ID |
| 63 | * @param intentService the intent service |
| 64 | */ |
| 65 | IntentSynchronizer(ApplicationId appId, IntentService intentService) { |
| 66 | this.appId = appId; |
| 67 | this.intentService = intentService; |
| 68 | pushedRouteIntents = new ConcurrentHashMap<>(); |
| 69 | |
| 70 | bgpIntentsSynchronizerExecutor = Executors.newSingleThreadExecutor( |
| 71 | new ThreadFactoryBuilder() |
| 72 | .setNameFormat("bgp-intents-synchronizer-%d").build()); |
| 73 | } |
| 74 | |
| 75 | /** |
| 76 | * Starts the synchronizer. |
| 77 | */ |
| 78 | public void start() { |
| 79 | bgpIntentsSynchronizerExecutor.execute(new Runnable() { |
| 80 | @Override |
| 81 | public void run() { |
| 82 | doIntentSynchronizationThread(); |
| 83 | } |
| 84 | }); |
| 85 | } |
| 86 | |
| 87 | /** |
| 88 | * Stops the synchronizer. |
| 89 | */ |
| 90 | public void stop() { |
| 91 | // Stop the thread(s) |
| 92 | bgpIntentsSynchronizerExecutor.shutdownNow(); |
| 93 | |
| 94 | // |
| 95 | // Withdraw all SDN-IP intents |
| 96 | // |
| 97 | if (!isElectedLeader) { |
| 98 | return; // Nothing to do: not the leader anymore |
| 99 | } |
| 100 | log.debug("Withdrawing all SDN-IP Route Intents..."); |
| 101 | for (Intent intent : intentService.getIntents()) { |
| 102 | if (!(intent instanceof MultiPointToSinglePointIntent) |
| 103 | || !intent.appId().equals(appId)) { |
| 104 | continue; |
| 105 | } |
| 106 | intentService.withdraw(intent); |
| 107 | } |
| 108 | |
| 109 | pushedRouteIntents.clear(); |
| 110 | } |
| 111 | |
| 112 | //@Override TODO hook this up to something |
| 113 | public void leaderChanged(boolean isLeader) { |
| 114 | log.debug("Leader changed: {}", isLeader); |
| 115 | |
| 116 | if (!isLeader) { |
| 117 | this.isElectedLeader = false; |
| 118 | this.isActivatedLeader = false; |
| 119 | return; // Nothing to do |
| 120 | } |
| 121 | this.isActivatedLeader = false; |
| 122 | this.isElectedLeader = true; |
| 123 | |
| 124 | // |
| 125 | // Tell the Intents Synchronizer thread to start the synchronization |
| 126 | // |
| 127 | intentsSynchronizerSemaphore.release(); |
| 128 | } |
| 129 | |
| 130 | /** |
| 131 | * Gets the pushed route intents. |
| 132 | * |
| 133 | * @return the pushed route intents |
| 134 | */ |
| 135 | public Collection<MultiPointToSinglePointIntent> getPushedRouteIntents() { |
| 136 | List<MultiPointToSinglePointIntent> pushedIntents = new LinkedList<>(); |
| 137 | |
| 138 | for (Map.Entry<Ip4Prefix, MultiPointToSinglePointIntent> entry : |
| 139 | pushedRouteIntents.entrySet()) { |
| 140 | pushedIntents.add(entry.getValue()); |
| 141 | } |
| 142 | return pushedIntents; |
| 143 | } |
| 144 | |
| 145 | /** |
| 146 | * Thread for Intent Synchronization. |
| 147 | */ |
| 148 | private void doIntentSynchronizationThread() { |
| 149 | boolean interrupted = false; |
| 150 | try { |
| 151 | while (!interrupted) { |
| 152 | try { |
| 153 | intentsSynchronizerSemaphore.acquire(); |
| 154 | // |
| 155 | // Drain all permits, because a single synchronization is |
| 156 | // sufficient. |
| 157 | // |
| 158 | intentsSynchronizerSemaphore.drainPermits(); |
| 159 | } catch (InterruptedException e) { |
| 160 | log.debug("Interrupted while waiting to become " + |
| 161 | "Intent Synchronization leader"); |
| 162 | interrupted = true; |
| 163 | break; |
| 164 | } |
| 165 | syncIntents(); |
| 166 | } |
| 167 | } finally { |
| 168 | if (interrupted) { |
| 169 | Thread.currentThread().interrupt(); |
| 170 | } |
| 171 | } |
| 172 | } |
| 173 | |
| 174 | /** |
| 175 | * Submits a multi-point-to-single-point intent. |
| 176 | * |
| 177 | * @param prefix the IPv4 matching prefix for the intent to submit |
| 178 | * @param intent the intent to submit |
| 179 | */ |
| 180 | void submitRouteIntent(Ip4Prefix prefix, |
| 181 | MultiPointToSinglePointIntent intent) { |
| 182 | synchronized (this) { |
| 183 | if (isElectedLeader && isActivatedLeader) { |
| 184 | log.debug("Intent installation: adding Intent for prefix: {}", |
| 185 | prefix); |
| 186 | intentService.submit(intent); |
| 187 | } |
| 188 | |
| 189 | // Maintain the Intent |
| 190 | pushedRouteIntents.put(prefix, intent); |
| 191 | } |
| 192 | } |
| 193 | |
| 194 | /** |
| 195 | * Withdraws a multi-point-to-single-point intent. |
| 196 | * |
| 197 | * @param prefix the IPv4 matching prefix for the intent to withdraw. |
| 198 | */ |
| 199 | void withdrawRouteIntent(Ip4Prefix prefix) { |
| 200 | synchronized (this) { |
| 201 | MultiPointToSinglePointIntent intent = |
| 202 | pushedRouteIntents.remove(prefix); |
| 203 | |
| 204 | if (intent == null) { |
| 205 | log.debug("There is no intent in pushedRouteIntents to delete " + |
| 206 | "for prefix: {}", prefix); |
| 207 | return; |
| 208 | } |
| 209 | |
| 210 | if (isElectedLeader && isActivatedLeader) { |
| 211 | log.debug("Intent installation: deleting Intent for prefix: {}", |
| 212 | prefix); |
| 213 | intentService.withdraw(intent); |
| 214 | } |
| 215 | } |
| 216 | } |
| 217 | |
| 218 | /** |
| 219 | * Performs Intents Synchronization between the internally stored Route |
| 220 | * Intents and the installed Route Intents. |
| 221 | */ |
| 222 | private void syncIntents() { |
| 223 | synchronized (this) { |
| 224 | if (!isElectedLeader) { |
| 225 | return; // Nothing to do: not the leader anymore |
| 226 | } |
| 227 | log.debug("Syncing SDN-IP Route Intents..."); |
| 228 | |
| 229 | Map<Ip4Prefix, MultiPointToSinglePointIntent> fetchedIntents = |
| 230 | new HashMap<>(); |
| 231 | |
| 232 | // |
| 233 | // Fetch all intents, and classify the Multi-Point-to-Point Intents |
| 234 | // based on the matching prefix. |
| 235 | // |
| 236 | for (Intent intent : intentService.getIntents()) { |
| 237 | |
| 238 | if (!(intent instanceof MultiPointToSinglePointIntent) |
| 239 | || !intent.appId().equals(appId)) { |
| 240 | continue; |
| 241 | } |
| 242 | MultiPointToSinglePointIntent mp2pIntent = |
| 243 | (MultiPointToSinglePointIntent) intent; |
| 244 | |
| 245 | Criterion c = |
| 246 | mp2pIntent.selector().getCriterion(Criterion.Type.IPV4_DST); |
| 247 | if (c != null && c instanceof IPCriterion) { |
| 248 | IPCriterion ipCriterion = (IPCriterion) c; |
| 249 | Ip4Prefix ip4Prefix = ipCriterion.ip().getIp4Prefix(); |
| 250 | if (ip4Prefix == null) { |
| 251 | // TODO: For now we support only IPv4 |
| 252 | continue; |
| 253 | } |
| 254 | fetchedIntents.put(ip4Prefix, mp2pIntent); |
| 255 | } else { |
| 256 | log.warn("No IPV4_DST criterion found for intent {}", |
| 257 | mp2pIntent.id()); |
| 258 | } |
| 259 | |
| 260 | } |
| 261 | |
| 262 | // |
| 263 | // Compare for each prefix the local IN-MEMORY Intents with the |
| 264 | // FETCHED Intents: |
| 265 | // - If the IN-MEMORY Intent is same as the FETCHED Intent, store |
| 266 | // the FETCHED Intent in the local memory (i.e., override the |
| 267 | // IN-MEMORY Intent) to preserve the original Intent ID |
| 268 | // - if the IN-MEMORY Intent is not same as the FETCHED Intent, |
| 269 | // delete the FETCHED Intent, and push/install the IN-MEMORY |
| 270 | // Intent. |
| 271 | // - If there is an IN-MEMORY Intent for a prefix, but no FETCHED |
| 272 | // Intent for same prefix, then push/install the IN-MEMORY |
| 273 | // Intent. |
| 274 | // - If there is a FETCHED Intent for a prefix, but no IN-MEMORY |
| 275 | // Intent for same prefix, then delete/withdraw the FETCHED |
| 276 | // Intent. |
| 277 | // |
| 278 | Collection<Pair<Ip4Prefix, MultiPointToSinglePointIntent>> |
| 279 | storeInMemoryIntents = new LinkedList<>(); |
| 280 | Collection<Pair<Ip4Prefix, MultiPointToSinglePointIntent>> |
| 281 | addIntents = new LinkedList<>(); |
| 282 | Collection<Pair<Ip4Prefix, MultiPointToSinglePointIntent>> |
| 283 | deleteIntents = new LinkedList<>(); |
| 284 | for (Map.Entry<Ip4Prefix, MultiPointToSinglePointIntent> entry : |
| 285 | pushedRouteIntents.entrySet()) { |
| 286 | Ip4Prefix prefix = entry.getKey(); |
| 287 | MultiPointToSinglePointIntent inMemoryIntent = |
| 288 | entry.getValue(); |
| 289 | MultiPointToSinglePointIntent fetchedIntent = |
| 290 | fetchedIntents.get(prefix); |
| 291 | |
| 292 | if (fetchedIntent == null) { |
| 293 | // |
| 294 | // No FETCHED Intent for same prefix: push the IN-MEMORY |
| 295 | // Intent. |
| 296 | // |
| 297 | addIntents.add(Pair.of(prefix, inMemoryIntent)); |
| 298 | continue; |
| 299 | } |
| 300 | |
| 301 | IntentState state = intentService.getIntentState(fetchedIntent.id()); |
| 302 | if (state == IntentState.WITHDRAWING || |
| 303 | state == IntentState.WITHDRAWN) { |
| 304 | // The intent has been withdrawn but according to our route |
| 305 | // table it should be installed. We'll reinstall it. |
| 306 | addIntents.add(Pair.of(prefix, inMemoryIntent)); |
| 307 | } |
| 308 | |
| 309 | // |
| 310 | // If IN-MEMORY Intent is same as the FETCHED Intent, |
| 311 | // store the FETCHED Intent in the local memory. |
| 312 | // |
| 313 | if (compareMultiPointToSinglePointIntents(inMemoryIntent, |
| 314 | fetchedIntent)) { |
| 315 | storeInMemoryIntents.add(Pair.of(prefix, fetchedIntent)); |
| 316 | } else { |
| 317 | // |
| 318 | // The IN-MEMORY Intent is not same as the FETCHED Intent, |
| 319 | // hence delete the FETCHED Intent, and install the |
| 320 | // IN-MEMORY Intent. |
| 321 | // |
| 322 | deleteIntents.add(Pair.of(prefix, fetchedIntent)); |
| 323 | addIntents.add(Pair.of(prefix, inMemoryIntent)); |
| 324 | } |
| 325 | fetchedIntents.remove(prefix); |
| 326 | } |
| 327 | |
| 328 | // |
| 329 | // Any remaining FETCHED Intents have to be deleted/withdrawn |
| 330 | // |
| 331 | for (Map.Entry<Ip4Prefix, MultiPointToSinglePointIntent> entry : |
| 332 | fetchedIntents.entrySet()) { |
| 333 | Ip4Prefix prefix = entry.getKey(); |
| 334 | MultiPointToSinglePointIntent fetchedIntent = entry.getValue(); |
| 335 | deleteIntents.add(Pair.of(prefix, fetchedIntent)); |
| 336 | } |
| 337 | |
| 338 | // |
| 339 | // Perform the actions: |
| 340 | // 1. Store in memory fetched intents that are same. Can be done |
| 341 | // even if we are not the leader anymore |
| 342 | // 2. Delete intents: check if the leader before each operation |
| 343 | // 3. Add intents: check if the leader before each operation |
| 344 | // |
| 345 | for (Pair<Ip4Prefix, MultiPointToSinglePointIntent> pair : |
| 346 | storeInMemoryIntents) { |
| 347 | Ip4Prefix prefix = pair.getLeft(); |
| 348 | MultiPointToSinglePointIntent intent = pair.getRight(); |
| 349 | log.debug("Intent synchronization: updating in-memory " + |
| 350 | "Intent for prefix: {}", prefix); |
| 351 | pushedRouteIntents.put(prefix, intent); |
| 352 | } |
| 353 | // |
| 354 | isActivatedLeader = true; // Allow push of Intents |
| 355 | for (Pair<Ip4Prefix, MultiPointToSinglePointIntent> pair : |
| 356 | deleteIntents) { |
| 357 | Ip4Prefix prefix = pair.getLeft(); |
| 358 | MultiPointToSinglePointIntent intent = pair.getRight(); |
| 359 | if (!isElectedLeader) { |
| 360 | isActivatedLeader = false; |
| 361 | return; |
| 362 | } |
| 363 | log.debug("Intent synchronization: deleting Intent for " + |
| 364 | "prefix: {}", prefix); |
| 365 | intentService.withdraw(intent); |
| 366 | } |
| 367 | // |
| 368 | for (Pair<Ip4Prefix, MultiPointToSinglePointIntent> pair : |
| 369 | addIntents) { |
| 370 | Ip4Prefix prefix = pair.getLeft(); |
| 371 | MultiPointToSinglePointIntent intent = pair.getRight(); |
| 372 | if (!isElectedLeader) { |
| 373 | isActivatedLeader = false; |
| 374 | return; |
| 375 | } |
| 376 | log.debug("Intent synchronization: adding Intent for " + |
| 377 | "prefix: {}", prefix); |
| 378 | intentService.submit(intent); |
| 379 | } |
| 380 | if (!isElectedLeader) { |
| 381 | isActivatedLeader = false; |
| 382 | } |
| 383 | log.debug("Syncing SDN-IP routes completed."); |
| 384 | } |
| 385 | } |
| 386 | |
| 387 | /** |
| 388 | * Compares two Multi-point to Single Point Intents whether they represent |
| 389 | * same logical intention. |
| 390 | * |
| 391 | * @param intent1 the first Intent to compare |
| 392 | * @param intent2 the second Intent to compare |
| 393 | * @return true if both Intents represent same logical intention, otherwise |
| 394 | * false |
| 395 | */ |
| 396 | private boolean compareMultiPointToSinglePointIntents( |
| 397 | MultiPointToSinglePointIntent intent1, |
| 398 | MultiPointToSinglePointIntent intent2) { |
| 399 | |
| 400 | return Objects.equal(intent1.appId(), intent2.appId()) && |
| 401 | Objects.equal(intent1.selector(), intent2.selector()) && |
| 402 | Objects.equal(intent1.treatment(), intent2.treatment()) && |
| 403 | Objects.equal(intent1.ingressPoints(), intent2.ingressPoints()) && |
| 404 | Objects.equal(intent1.egressPoint(), intent2.egressPoint()); |
| 405 | } |
| 406 | } |