[infinispan-dev] Unbalanced lock releases

[Sanne Grinovero]

Hello all,
I am getting an "IllegalMonitorStateException" while Infinispan
attempts to release a lock it doesn't own, basically at:
org.infinispan.container.EntryFactoryImpl.wrapEntryForWriting(EntryFactoryImpl.java:178

(I was using SKIP_LOCKING, so lockAcquired is false at this point).
I tried to fix it introducing an "if (lockAcquired)" in line 178, but
then the situation seems worse:

In "LockManagerImpl", line 174, reads:

boolean needToUnlock = possiblyLocked(entry)

where the javadoc of possiblyLocked reads:

"Inspects the entry for signs that it is possibly locked, and hence
would need to be unlocked. Note that this is not deterministic, and is
pessimistic in that even if an entry is not locked but *might* be
locked, this will return true.
As such, this should only be used to determine whether *unlocking* is
necessary, not whether locking is necessary. Unlocking an entry that
has not been locked has no effect, so this is just an optimisation. "

Still, some assumption seems wrong here as I'm experiencing the
following stacktrace :

java.lang.IllegalMonitorStateException
	at java.util.concurrent.locks.ReentrantLock$Sync.tryRelease(ReentrantLock.java:127)
	at java.util.concurrent.locks.AbstractQueuedSynchronizer.release(AbstractQueuedSynchronizer.java:1239)
	at java.util.concurrent.locks.ReentrantLock.unlock(ReentrantLock.java:431)
	at org.infinispan.util.concurrent.locks.containers.AbstractStripedLockContainer.releaseLock(AbstractStripedLockContainer.java:97)
	at org.infinispan.util.concurrent.locks.LockManagerImpl.unlock(LockManagerImpl.java:111)
	at org.infinispan.util.concurrent.locks.LockManagerImpl.releaseLocks(LockManagerImpl.java:183)
	at org.infinispan.interceptors.LockingInterceptor.cleanupLocks(LockingInterceptor.java:407)
	at org.infinispan.interceptors.LockingInterceptor.cleanLocksAndRethrow(LockingInterceptor.java:412)
	at org.infinispan.interceptors.LockingInterceptor.visitReplaceCommand(LockingInterceptor.java:340)
	at org.infinispan.commands.write.ReplaceCommand.acceptVisitor(ReplaceCommand.java:59)
	at org.infinispan.interceptors.base.CommandInterceptor.invokeNextInterceptor(CommandInterceptor.java:118)
	at org.infinispan.interceptors.base.CommandInterceptor.handleDefault(CommandInterceptor.java:132)
	at org.infinispan.commands.AbstractVisitor.visitReplaceCommand(AbstractVisitor.java:66)
	at org.infinispan.commands.write.ReplaceCommand.acceptVisitor(ReplaceCommand.java:59)
	at org.infinispan.interceptors.base.CommandInterceptor.invokeNextInterceptor(CommandInterceptor.java:118)
	at org.infinispan.interceptors.TxInterceptor.enlistWriteAndInvokeNext(TxInterceptor.java:184)
	at org.infinispan.interceptors.TxInterceptor.visitReplaceCommand(TxInterceptor.java:142)
	at org.infinispan.interceptors.DistTxInterceptor.visitReplaceCommand(DistTxInterceptor.java:90)
	at org.infinispan.commands.write.ReplaceCommand.acceptVisitor(ReplaceCommand.java:59)
	at org.infinispan.interceptors.base.CommandInterceptor.invokeNextInterceptor(CommandInterceptor.java:118)
	at org.infinispan.interceptors.InvocationContextInterceptor.handleAll(InvocationContextInterceptor.java:87)
	at org.infinispan.interceptors.InvocationContextInterceptor.handleDefault(InvocationContextInterceptor.java:58)
	at org.infinispan.commands.AbstractVisitor.visitReplaceCommand(AbstractVisitor.java:66)
	at org.infinispan.commands.write.ReplaceCommand.acceptVisitor(ReplaceCommand.java:59)
	at org.infinispan.interceptors.InterceptorChain.invoke(InterceptorChain.java:273)
	at org.infinispan.CacheDelegate.replace(CacheDelegate.java:475)
	at org.infinispan.CacheSupport.replace(CacheSupport.java:96)
	at org.infinispan.lucene.readlocks.DistributedSegmentReadLocker.acquireReadLock(DistributedSegmentReadLocker.java:146)
	at org.infinispan.lucene.readlocks.StressTestReadLocksTest$LockUser.run(StressTestReadLocksTest.java:74)
	at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
	at java.lang.Thread.run(Thread.java:662)

It's totally possible that the exception wouldn't happen without my
"fix" mentioned above, but then I get the IllegalMonitorStateException
earlier.
Any hint?

I'm sharing my failing testcase on GitHub, branch
"IllegalMonitorStateException", forked from 4.2.x :
https://github.com/Sanne/infinispan/tree/IllegalMonitorStateException

Cheers,
Sanne