package org.lttng.ust.agent;
+import java.util.Collection;
import java.util.HashSet;
-import java.util.LinkedList;
-import java.util.List;
import java.util.Map;
import java.util.NavigableMap;
import java.util.Set;
import java.util.concurrent.ConcurrentSkipListMap;
import java.util.concurrent.atomic.AtomicInteger;
+import org.lttng.ust.agent.client.ILttngTcpClientListener;
import org.lttng.ust.agent.client.LttngTcpSessiondClient;
+import org.lttng.ust.agent.filter.FilterChangeNotifier;
+import org.lttng.ust.agent.session.EventRule;
+import org.lttng.ust.agent.utils.LttngUstAgentLogger;
/**
* Base implementation of a {@link ILttngAgent}.
* @param <T>
* The type of logging handler that should register to this agent
*/
-public abstract class AbstractLttngAgent<T extends ILttngHandler> implements ILttngAgent<T> {
+public abstract class AbstractLttngAgent<T extends ILttngHandler>
+ implements ILttngAgent<T>, ILttngTcpClientListener {
private static final String WILDCARD = "*";
private static final int INIT_TIMEOUT = 3; /* Seconds */
* falls to 0, this means we can avoid sending log events through JNI
* because nobody wants them.
*
- * It uses a concurrent hash set", so that the {@link #isEventEnabled} and
+ * It uses a concurrent hash map, so that the {@link #isEventEnabled} and
* read methods do not need to take a synchronization lock.
*/
private final Map<String, Integer> enabledEvents = new ConcurrentHashMap<String, Integer>();
/** Number of sessions currently enabling the wildcard "*" event */
private final AtomicInteger enabledWildcards = new AtomicInteger(0);
+ /**
+ * The application contexts currently enabled in the tracing sessions.
+ *
+ * It is first indexed by context retriever, then by context name. This
+ * allows to efficiently query all the contexts for a given retriever.
+ *
+ * Works similarly as {@link #enabledEvents}, but for app contexts (and with
+ * an extra degree of indexing).
+ *
+ * TODO Could be changed to a Guava Table once/if we start using it.
+ */
+ private final Map<String, Map<String, Integer>> enabledAppContexts = new ConcurrentHashMap<String, Map<String, Integer>>();
+
/** Tracing domain. Defined by the sub-classes via the constructor. */
private final Domain domain;
if (initialized) {
return;
}
+
+ LttngUstAgentLogger.log(AbstractLttngAgent.class, "Initializing Agent for domain: " + domain.name());
+
String rootClientThreadName = "Root sessiond client started by agent: " + this.getClass().getSimpleName();
- rootSessiondClient = new LttngTcpSessiondClient(this, true);
+ rootSessiondClient = new LttngTcpSessiondClient(this, getDomain().value(), true);
rootSessiondClientThread = new Thread(rootSessiondClient, rootClientThreadName);
rootSessiondClientThread.setDaemon(true);
rootSessiondClientThread.start();
String userClientThreadName = "User sessiond client started by agent: " + this.getClass().getSimpleName();
- userSessiondClient = new LttngTcpSessiondClient(this, false);
+ userSessiondClient = new LttngTcpSessiondClient(this, getDomain().value(), false);
userSessiondClientThread = new Thread(userSessiondClient, userClientThreadName);
userSessiondClientThread.setDaemon(true);
userSessiondClientThread.start();
* Dispose the agent
*/
private void dispose() {
+ LttngUstAgentLogger.log(AbstractLttngAgent.class, "Disposing Agent for domain: " + domain.name());
+
/*
* Only called from a synchronized (registeredHandlers) block, should
* not need additional synchronization.
userSessiondClient = null;
userSessiondClientThread = null;
- /* Reset all enabled event counts to 0 */
+ /*
+ * Send filter change notifications for all event rules currently
+ * active, then clear them.
+ */
+ FilterChangeNotifier fcn = FilterChangeNotifier.getInstance();
+
+ for (Map.Entry<String, Integer> entry : enabledEvents.entrySet()) {
+ String eventName = entry.getKey();
+ Integer nb = entry.getValue();
+ for (int i = 0; i < nb.intValue(); i++) {
+ fcn.removeEventRules(eventName);
+ }
+ }
enabledEvents.clear();
+
+ for (Map.Entry<String, Integer> entry : enabledEventPrefixes.entrySet()) {
+ /* Re-add the * at the end, the FCN tracks the rules that way */
+ String eventName = (entry.getKey() + "*");
+ Integer nb = entry.getValue();
+ for (int i = 0; i < nb.intValue(); i++) {
+ fcn.removeEventRules(eventName);
+ }
+ }
enabledEventPrefixes.clear();
- enabledWildcards.set(0);
- initialized = false;
+ int wildcardRules = enabledWildcards.getAndSet(0);
+ for (int i = 0; i < wildcardRules; i++) {
+ fcn.removeEventRules(WILDCARD);
+ }
+ /*
+ * Also clear tracked app contexts (no filter notifications sent for
+ * those currently).
+ */
+ enabledAppContexts.clear();
+
+ initialized = false;
}
- /**
- * Callback for the TCP clients to notify the agent that a request for
- * enabling an event was sent from the session daemon.
- *
- * @param eventName
- * The name of the event that was requested to be enabled.
- * @return Since we do not track individual sessions, right now this command
- * cannot fail. It will always return true.
- */
- public boolean eventEnabled(String eventName) {
+ @Override
+ public boolean eventEnabled(EventRule eventRule) {
+ /* Notify the filter change manager of the command */
+ FilterChangeNotifier.getInstance().addEventRule(eventRule);
+
+ String eventName = eventRule.getEventName();
+
if (eventName.equals(WILDCARD)) {
enabledWildcards.incrementAndGet();
return true;
}
-
if (eventName.endsWith(WILDCARD)) {
/* Strip the "*" from the name. */
String prefix = eventName.substring(0, eventName.length() - 1);
- return incrementEventCount(prefix, enabledEventPrefixes);
+ return incrementRefCount(prefix, enabledEventPrefixes);
}
- return incrementEventCount(eventName, enabledEvents);
+ return incrementRefCount(eventName, enabledEvents);
}
- /**
- * Callback for the TCP clients to notify the agent that a request for
- * disabling an event was sent from the session daemon.
- *
- * @param eventName
- * The name of the event that was requested to be disabled.
- * @return True if the command completed successfully, false if we should
- * report an error (event was not enabled, etc.)
- */
+ @Override
public boolean eventDisabled(String eventName) {
+ /* Notify the filter change manager of the command */
+ FilterChangeNotifier.getInstance().removeEventRules(eventName);
+
if (eventName.equals(WILDCARD)) {
int newCount = enabledWildcards.decrementAndGet();
if (newCount < 0) {
enabledWildcards.incrementAndGet();
return false;
}
+ return true;
}
if (eventName.endsWith(WILDCARD)) {
/* Strip the "*" from the name. */
String prefix = eventName.substring(0, eventName.length() - 1);
- return decrementEventCount(prefix, enabledEventPrefixes);
+ return decrementRefCount(prefix, enabledEventPrefixes);
}
- return decrementEventCount(eventName, enabledEvents);
+ return decrementRefCount(eventName, enabledEvents);
}
+ @Override
+ public boolean appContextEnabled(String contextRetrieverName, String contextName) {
+ synchronized (enabledAppContexts) {
+ Map<String, Integer> retrieverMap = enabledAppContexts.get(contextRetrieverName);
+ if (retrieverMap == null) {
+ /* There is no submap for this retriever, let's create one. */
+ retrieverMap = new ConcurrentHashMap<String, Integer>();
+ enabledAppContexts.put(contextRetrieverName, retrieverMap);
+ }
+
+ return incrementRefCount(contextName, retrieverMap);
+ }
+ }
+
+ @Override
+ public boolean appContextDisabled(String contextRetrieverName, String contextName) {
+ synchronized (enabledAppContexts) {
+ Map<String, Integer> retrieverMap = enabledAppContexts.get(contextRetrieverName);
+ if (retrieverMap == null) {
+ /* There was no submap for this retriever, invalid command? */
+ return false;
+ }
+
+ boolean ret = decrementRefCount(contextName, retrieverMap);
+
+ /* If the submap is now empty we can remove it from the main map. */
+ if (retrieverMap.isEmpty()) {
+ enabledAppContexts.remove(contextRetrieverName);
+ }
+
+ return ret;
+ }
+ }
+
+ /*
+ * Implementation of this method is domain-specific.
+ */
+ @Override
+ public abstract Collection<String> listAvailableEvents();
+
@Override
public boolean isEventEnabled(String eventName) {
/* If at least one session enabled the "*" wildcard, send the event */
}
@Override
- public Iterable<String> listEnabledEvents() {
- List<String> events = new LinkedList<String>();
-
- if (enabledWildcards.get() > 0) {
- events.add(WILDCARD);
- }
- for (String prefix : enabledEventPrefixes.keySet()) {
- events.add(new String(prefix + WILDCARD));
- }
- events.addAll(enabledEvents.keySet());
- return events;
+ public Collection<Map.Entry<String, Map<String, Integer>>> getEnabledAppContexts() {
+ return enabledAppContexts.entrySet();
}
- private static boolean incrementEventCount(String eventName, Map<String, Integer> eventMap) {
- synchronized (eventMap) {
- Integer count = eventMap.get(eventName);
+ private static boolean incrementRefCount(String key, Map<String, Integer> refCountMap) {
+ synchronized (refCountMap) {
+ Integer count = refCountMap.get(key);
if (count == null) {
/* This is the first instance of this event being enabled */
- eventMap.put(eventName, Integer.valueOf(1));
+ refCountMap.put(key, Integer.valueOf(1));
return true;
}
if (count.intValue() <= 0) {
throw new IllegalStateException();
}
/* The event was already enabled, increment its refcount */
- eventMap.put(eventName, Integer.valueOf(count.intValue() + 1));
+ refCountMap.put(key, Integer.valueOf(count.intValue() + 1));
return true;
}
}
- private static boolean decrementEventCount(String eventName, Map<String, Integer> eventMap) {
- synchronized (eventMap) {
- Integer count = eventMap.get(eventName);
+ private static boolean decrementRefCount(String key, Map<String, Integer> refCountMap) {
+ synchronized (refCountMap) {
+ Integer count = refCountMap.get(key);
if (count == null || count.intValue() <= 0) {
/*
* The sessiond asked us to disable an event that was not
* This is the last instance of this event being disabled,
* remove it from the map so that we stop sending it.
*/
- eventMap.remove(eventName);
+ refCountMap.remove(key);
return true;
}
/*
* Other sessions are still looking for this event, simply decrement
* its refcount.
*/
- eventMap.put(eventName, Integer.valueOf(count.intValue() - 1));
+ refCountMap.put(key, Integer.valueOf(count.intValue() - 1));
return true;
}
}