Deadlocked Thread State is RUNNABLE?

[Daniel D. Daugherty]

Resending and including the Runtime team since I think that team
owns deadlock detection support at this point...

Dan


Jeremy Manson wrote:
> Hi folks,
>
> I notice that when you send a sigquit to a VM, and threads are
> deadlocked in class initialization, then the thread state is reported
> as RUNNABLE.  Is this deliberate?
>
> With the attached program (which mostly deadlocks on clinit - I don't
> have the time to remember how to write the
> 100-percent-will-always-deadlock version today), here is the output
> from JDK7 b74.
>
> 2009-11-17 15:41:14
> Full thread dump OpenJDK Server VM (17.0-b03 mixed mode):
>
> "DestroyJavaVM" prio=10 tid=0xaf519c00 nid=0x2221 waiting on condition
> [0x00000000]
>    java.lang.Thread.State: RUNNABLE
>
> "Thread-1" prio=10 tid=0xaf518000 nid=0x2230 in Object.wait() [0xaf3db000]
>    java.lang.Thread.State: RUNNABLE
>         at NPE$2.run(NPE.java:60)
>         at java.lang.Thread.run(Thread.java:717)
>
> "Thread-0" prio=10 tid=0xaf516800 nid=0x222f in Object.wait() [0xaf42c000]
>    java.lang.Thread.State: RUNNABLE
>         at Base.<clinit>(NPE.java:33)
>         at NPE$1.run(NPE.java:54)
>         at java.lang.Thread.run(Thread.java:717)
>
> "Low Memory Detector" daemon prio=10 tid=0xaf500c00 nid=0x222d
> runnable [0x00000000]
>    java.lang.Thread.State: RUNNABLE
>
> "CompilerThread1" daemon prio=10 tid=0x08109c00 nid=0x222c waiting on
> condition [0x00000000]
>    java.lang.Thread.State: RUNNABLE
>
> "CompilerThread0" daemon prio=10 tid=0x08107800 nid=0x222b waiting on
> condition [0x00000000]
>    java.lang.Thread.State: RUNNABLE
>
> "Signal Dispatcher" daemon prio=10 tid=0x08105c00 nid=0x222a waiting
> on condition [0x00000000]
>    java.lang.Thread.State: RUNNABLE
>
> "Finalizer" daemon prio=10 tid=0x080f6c00 nid=0x2229 in Object.wait()
> [0xaf821000]
>    java.lang.Thread.State: WAITING (on object monitor)
>         at java.lang.Object.wait(Native Method)
>         - waiting on <0xecf30bd0> (a java.lang.ref.ReferenceQueue$Lock)
>         at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:135)
>         - locked <0xecf30bd0> (a java.lang.ref.ReferenceQueue$Lock)
>         at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:151)
>         at java.lang.ref.Finalizer$FinalizerThread.run(Finalizer.java:177)
>
> "Reference Handler" daemon prio=10 tid=0x080f2000 nid=0x2228 in
> Object.wait() [0xaf872000]
>    java.lang.Thread.State: WAITING (on object monitor)
>         at java.lang.Object.wait(Native Method)
>         - waiting on <0xecf30990> (a java.lang.ref.Reference$Lock)
>         at java.lang.Object.wait(Object.java:502)
>         at java.lang.ref.Reference$ReferenceHandler.run(Reference.java:133)
>         - locked <0xecf30990> (a java.lang.ref.Reference$Lock)
>
> "VM Thread" prio=10 tid=0x080ed400 nid=0x2227 runnable
>
> "GC task thread#0 (ParallelGC)" prio=10 tid=0x08057400 nid=0x2222 runnable
>
> "GC task thread#1 (ParallelGC)" prio=10 tid=0x08058c00 nid=0x2223 runnable
>
> "GC task thread#2 (ParallelGC)" prio=10 tid=0x0805a000 nid=0x2224 runnable
>
> "GC task thread#3 (ParallelGC)" prio=10 tid=0x0805b800 nid=0x2225 runnable
>
> "VM Periodic Task Thread" prio=10 tid=0xaf502c00 nid=0x222e waiting on
> condition
>
> JNI global references: 643
>
> Heap
>  PSYoungGen      total 12480K, used 860K [0xecf30000, 0xedd10000, 0xf40f0000)
>   eden space 10752K, 8% used [0xecf30000,0xed007148,0xed9b0000)
>   from space 1728K, 0% used [0xedb60000,0xedb60000,0xedd10000)
>   to   space 1728K, 0% used [0xed9b0000,0xed9b0000,0xedb60000)
>  PSOldGen        total 113792K, used 0K [0xb40f0000, 0xbb010000, 0xecf30000)
>   object space 113792K, 0% used [0xb40f0000,0xb40f0000,0xbb010000)
>  PSPermGen       total 16384K, used 1764K [0xb00f0000, 0xb10f0000, 0xb40f0000)
>   object space 16384K, 10% used [0xb00f0000,0xb02a91d0,0xb10f0000)
>