import com.google.common.base.MoreObjects.ToStringHelper;
import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
import java.util.Collection;
+import java.util.List;
import java.util.Optional;
+import java.util.OptionalLong;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;
import java.util.function.Consumer;
-import javax.annotation.concurrent.GuardedBy;
-import javax.annotation.concurrent.NotThreadSafe;
+import org.checkerframework.checker.lock.qual.GuardedBy;
+import org.checkerframework.checker.lock.qual.Holding;
import org.eclipse.jdt.annotation.NonNull;
import org.opendaylight.controller.cluster.access.concepts.Request;
import org.opendaylight.controller.cluster.access.concepts.RequestException;
/**
* Base class for a connection to the backend. Responsible to queueing and dispatch of requests toward the backend.
* Can be in three conceptual states: Connecting, Connected and Reconnecting, which are represented by public final
- * classes exposed from this package.
+ * classes exposed from this package. This class NOT thread-safe, not are its subclasses expected to be thread-safe.
*
* @author Robert Varga
*/
-@NotThreadSafe
public abstract class AbstractClientConnection<T extends BackendInfo> {
private static final Logger LOG = LoggerFactory.getLogger(AbstractClientConnection.class);
private static final long MAX_DELAY_NANOS = TimeUnit.SECONDS.toNanos(MAX_DELAY_SECONDS);
private final Lock lock = new ReentrantLock();
- private final ClientActorContext context;
- @GuardedBy("lock")
- private final TransmitQueue queue;
+ private final @NonNull ClientActorContext context;
private final @NonNull Long cookie;
private final String backendName;
+ @GuardedBy("lock")
+ private final TransmitQueue queue;
@GuardedBy("lock")
private boolean haveTimer;
// Private constructor to avoid code duplication.
private AbstractClientConnection(final AbstractClientConnection<T> oldConn, final TransmitQueue newQueue,
final String backendName) {
- this.context = requireNonNull(oldConn.context);
- this.cookie = requireNonNull(oldConn.cookie);
+ context = oldConn.context;
+ cookie = oldConn.cookie;
this.backendName = requireNonNull(backendName);
- this.queue = requireNonNull(newQueue);
+ queue = requireNonNull(newQueue);
// Will be updated in finishReplay if needed.
- this.lastReceivedTicks = oldConn.lastReceivedTicks;
+ lastReceivedTicks = oldConn.lastReceivedTicks;
}
// This constructor is only to be called by ConnectingClientConnection constructor.
this.context = requireNonNull(context);
this.cookie = requireNonNull(cookie);
this.backendName = requireNonNull(backendName);
- this.queue = new TransmitQueue.Halted(queueDepth);
- this.lastReceivedTicks = currentTime();
+ queue = new TransmitQueue.Halted(queueDepth);
+ lastReceivedTicks = currentTime();
}
// This constructor is only to be called (indirectly) by ReconnectingClientConnection constructor.
requireNonNull(oldConn.context).messageSlicer()), newBackend.getName());
}
- public final ClientActorContext context() {
+ public final @NonNull ClientActorContext context() {
return context;
}
return cookie;
}
- public final ActorRef localActor() {
+ public final @NonNull ActorRef localActor() {
return context.self();
}
*
* <p>
* Note that unlike {@link #sendRequest(Request, Consumer)}, this method does not exert backpressure, hence it
- * should never be called from an application thread.
+ * should never be called from an application thread and serves mostly for moving requests between queues.
*
* @param request Request to send
* @param callback Callback to invoke
}
}
- @GuardedBy("lock")
+ @Holding("lock")
private void commonEnqueue(final ConnectionEntry entry, final long now) {
final RequestException maybePoison = poisoned;
if (maybePoison != null) {
return queue.drain();
}
- @GuardedBy("lock")
+ @Holding("lock")
final void finishReplay(final ReconnectForwarder forwarder) {
setForwarder(forwarder);
lock.unlock();
}
- @GuardedBy("lock")
+ @Holding("lock")
final void setForwarder(final ReconnectForwarder forwarder) {
queue.setForwarder(forwarder, currentTime());
}
- @GuardedBy("lock")
+ @Holding("lock")
abstract ClientActorBehavior<T> lockedReconnect(ClientActorBehavior<T> current,
RequestException runtimeRequestException);
*
* @param delay Delay, in nanoseconds
*/
- @GuardedBy("lock")
+ @Holding("lock")
private void scheduleTimer(final long delay) {
if (haveTimer) {
LOG.debug("{}: timer already scheduled on {}", context.persistenceId(), this);
*/
@VisibleForTesting
final ClientActorBehavior<T> runTimer(final ClientActorBehavior<T> current) {
- final Optional<Long> delay;
-
lock.lock();
+
+ final List<ConnectionEntry> poisonEntries;
+ final NoProgressException poisonCause;
try {
haveTimer = false;
final long now = currentTime();
// The following line is only reliable when queue is not forwarding, but such state should not last long.
// FIXME: BUG-8422: this may not be accurate w.r.t. replayed entries
final long ticksSinceProgress = queue.ticksStalling(now);
- if (ticksSinceProgress >= context.config().getNoProgressTimeout()) {
- LOG.error("Queue {} has not seen progress in {} seconds, failing all requests", this,
- TimeUnit.NANOSECONDS.toSeconds(ticksSinceProgress));
+ if (ticksSinceProgress < context.config().getNoProgressTimeout()) {
+ // Requests are always scheduled in sequence, hence checking for timeout is relatively straightforward.
+ // Note we use also inquire about the delay, so we can re-schedule if needed, hence the unusual
+ // tri-state return convention.
+ final OptionalLong delay = lockedCheckTimeout(now);
+ if (delay == null) {
+ // We have timed out. There is no point in scheduling a timer
+ LOG.debug("{}: connection {} timed out", context.persistenceId(), this);
+ return lockedReconnect(current, new RuntimeRequestException("Backend connection timed out",
+ new TimeoutException()));
+ }
- lockedPoison(new NoProgressException(ticksSinceProgress));
- current.removeConnection(this);
- return current;
- }
+ if (delay.isPresent()) {
+ // If there is new delay, schedule a timer
+ scheduleTimer(delay.orElseThrow());
+ } else {
+ LOG.debug("{}: not scheduling timeout on {}", context.persistenceId(), this);
+ }
- // Requests are always scheduled in sequence, hence checking for timeout is relatively straightforward.
- // Note we use also inquire about the delay, so we can re-schedule if needed, hence the unusual tri-state
- // return convention.
- delay = lockedCheckTimeout(now);
- if (delay == null) {
- // We have timed out. There is no point in scheduling a timer
- LOG.debug("{}: connection {} timed out", context.persistenceId(), this);
- return lockedReconnect(current, new RuntimeRequestException("Backend connection timed out",
- new TimeoutException()));
+ return current;
}
- if (delay.isPresent()) {
- // If there is new delay, schedule a timer
- scheduleTimer(delay.get());
- } else {
- LOG.debug("{}: not scheduling timeout on {}", context.persistenceId(), this);
- }
+ LOG.error("Queue {} has not seen progress in {} seconds, failing all requests", this,
+ TimeUnit.NANOSECONDS.toSeconds(ticksSinceProgress));
+ poisonCause = new NoProgressException(ticksSinceProgress);
+ poisonEntries = lockedPoison(poisonCause);
+ current.removeConnection(this);
} finally {
lock.unlock();
}
+ poison(poisonEntries, poisonCause);
return current;
}
@VisibleForTesting
- final Optional<Long> checkTimeout(final long now) {
+ final OptionalLong checkTimeout(final long now) {
lock.lock();
try {
return lockedCheckTimeout(now);
@SuppressFBWarnings(value = "NP_OPTIONAL_RETURN_NULL",
justification = "Returning null Optional is documented in the API contract.")
@GuardedBy("lock")
- private Optional<Long> lockedCheckTimeout(final long now) {
+ private OptionalLong lockedCheckTimeout(final long now) {
if (queue.isEmpty()) {
LOG.debug("{}: connection {} is empty", context.persistenceId(), this);
- return Optional.empty();
+ return OptionalLong.empty();
}
final long backendSilentTicks = backendSilentTicks(now);
final long beenOpen = now - head.getEnqueuedTicks();
final long requestTimeout = context.config().getRequestTimeout();
if (beenOpen < requestTimeout) {
- return Optional.of(requestTimeout - beenOpen);
+ return OptionalLong.of(requestTimeout - beenOpen);
}
tasksTimedOut++;
queue.tryTransmit(now);
}
- return Optional.empty();
+ return OptionalLong.empty();
}
private void timeoutEntry(final ConnectionEntry entry, final long beenOpen) {
}
final void poison(final RequestException cause) {
+ final List<ConnectionEntry> entries;
+
lock.lock();
try {
- lockedPoison(cause);
+ entries = lockedPoison(cause);
} finally {
lock.unlock();
}
+
+ poison(entries, cause);
}
- @GuardedBy("lock")
- private void lockedPoison(final RequestException cause) {
+ // Do not hold any locks while calling this
+ private static void poison(final Collection<? extends ConnectionEntry> entries, final RequestException cause) {
+ for (ConnectionEntry e : entries) {
+ final Request<?, ?> request = e.getRequest();
+ LOG.trace("Poisoning request {}", request, cause);
+ e.complete(request.toRequestFailure(cause));
+ }
+ }
+
+ @Holding("lock")
+ private List<ConnectionEntry> lockedPoison(final RequestException cause) {
poisoned = enrichPoison(cause);
- queue.poison(cause);
+ return queue.poison();
}
RequestException enrichPoison(final RequestException ex) {
}
if (maybeEntry.isPresent()) {
- final TransmittedConnectionEntry entry = maybeEntry.get();
+ final TransmittedConnectionEntry entry = maybeEntry.orElseThrow();
LOG.debug("Completing {} with {}", entry, envelope);
entry.complete(envelope.getMessage());
}