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Acquire VThreadInspector before vmThreadListMutex to avoid deadlock
VirtualThreads.park
performs operations in the below order:Set
VThreadInspector
to-1
and then acquirevmThreadListMutex
JVMTI GetThreadState -> ... -> getVMThread
follows the below order:Acquire
vmThreadListMutex
and then spin untilVThreadInspector != -1
A deadlock occurs because the order of operations is inconsistent
between
VirtualThreads.park
andJVMTI GetThreadState
.To resolve the deadlock, the operations in
getVMThread
are swappedto match the operations in
VirtualThreads.park
:Acquire
VThreadInspector
and then acquirevmThreadListMutex
VirtualThread State: *PINNED is identical to *PARKED
RI and JTReg tests expect the same JVMTI thread state for
PARKED
andPINNED
TIMED_PARKED
andTIMED_PINNED
Related: #18642
Signed-off-by: Babneet Singh [email protected]