RFR (XS): 8022595: JSR292: deadlock during class loading of MethodHandles, MethodHandleImpl & MethodHandleNatives
vladimir.x.ivanov at oracle.com
Tue Aug 20 10:05:45 PDT 2013
201 lines changed: 201 ins; 0 del; 0 mod;
Some classes in j.l.invoke have circular dependencies between them which
leads to deadlocks during class initialization when multiple threads
exercise JSR292 functionality.
JSR292 core classes are among "well-known" classes to VM and they are
preloaded during VM startup (see
SystemDictionary::initialize_preloaded_classes). However, it doesn't
force preloaded classes to be initialized (doesn't execute static
initializers). Thus, these classes should be explicitly pre-initialized
in order to avoid deadlocks.
Based on my observations of possible deadlock scenarios, I chose 3
classes to pre-initialize:
I placed the code right after compilers initialization because during
method resolution for signature polymorphic intrinsics, compilation
tasks are issued (see SystemDictionary::find_method_handle_intrinsic for
details) and they are missed if compiler subsystem isn't ready yet.
Testing: failing test, regression test, JPRT, jdk/test/j/l/invoke,
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