[jboss-remoting-commits] JBoss Remoting SVN: r6403 - remoting2/branches/2.2/src/main/org/jboss/remoting.

[jboss-remoting-commits at lists.jboss.org]

Author: ron.sigal at jboss.com
Date: 2011-08-26 23:28:38 -0400 (Fri, 26 Aug 2011)
New Revision: 6403

Modified:
   remoting2/branches/2.2/src/main/org/jboss/remoting/ConnectionValidator.java
Log:
JBREM-1297: Synchronize on Client.connectionValidatorLock while calling MicroRemoteClientInvoker.terminateLease().

Modified: remoting2/branches/2.2/src/main/org/jboss/remoting/ConnectionValidator.java
===================================================================
--- remoting2/branches/2.2/src/main/org/jboss/remoting/ConnectionValidator.java	2011-08-27 03:19:11 UTC (rev 6402)
+++ remoting2/branches/2.2/src/main/org/jboss/remoting/ConnectionValidator.java	2011-08-27 03:28:38 UTC (rev 6403)
@@ -1049,7 +1049,35 @@
                   log.debug(ConnectionValidator.this + " shutting down lease pinger: " + leasePinger);
                   int disconnectTimeout = (failureDisconnectTimeout == -1) ? client.getDisconnectTimeout() : failureDisconnectTimeout;
                   if (trace) log.trace(ConnectionValidator.this + " disconnectTimeout: " + disconnectTimeout);
-                  sharedInvoker.terminateLease(null, disconnectTimeout, leasePinger);
+                  
+                  // Synchronizing on Client.connectionValidatorLock to prevent a deadlock:
+                  //
+                  // 1. a. This method calls MicroRemoteClientInvoker.terminateLease()
+                  //    b. MicroRemoteClientInvoker.terminateLease() synchronizes on MicroRemoteClientInvoker.clientLeaseLock 
+                  //    c. MicroRemoteClientInvoker.terminateLease() calls LeasePinger.stopPing()
+                  //    d. LeasePinger.stopPing() calls Client.notifyListeners()
+                  //    e. Client.notifyListeners() synchronizes on Client.connectionValidatorLock
+                  //
+                  // 2. a. Client.connect() calls Client.setupClientLease()
+                  //    b. Client.setupClientLease() synchronizes on Client.connectionValidatorLock
+                  //    c. Client.setupClientLease() calls MicroRemoteClientInvoker.establishLease()
+                  //    d. MicroRemoteClientInvoker.establishLease() synchronizes on MicroRemoteClientInvoker.clientLeaseLock
+                  //    e. MicroRemoteClientInvoker.establishLease() calls Client.addConnectionListener()
+                  //    f. Client.addConnectionListener() synchronizes on Client.connectionValidatorLock
+                  //
+                  // 3. a. Client.addConnectionListener() synchronizes on Client.connectionValidatorLock
+                  //    b. Client.addConnectionListener() calls new ConnectionValidator()
+                  //    c. new ConnectionValidator() calls MicroRemoteClientInvoker.getLeasePinger()
+                  //    d. MicroRemoteClientInvoker.getLeasePinger() synchronizes on MicroRemoteClientInvoker.clientLeaseLock
+                  //
+                  // By synchronizing on connectionValidatorLock here, we assure that all sequences acquire
+                  // Client.connectionValidatorLock first and then acquire MicroRemoteClientInvoker.clientLeaseLock.
+                  //
+                  // See JBREM-1242 and JBREM-1297.
+                  synchronized (Client.getConnectionValidatorLock())
+                  {
+                     sharedInvoker.terminateLease(null, disconnectTimeout, leasePinger);
+                  }
                }
                else
                {