RFR (S) 8232112: MDO extra_data_lock leaks during class unloading

[David Holmes]

Hi Coleen,

On 16/10/2019 11:48 pm, coleen.phillimore at oracle.com wrote:
> Summary: call the MDO destructor during class unloading.
> 
> Also moved the other C heap deallocation from method_data to 
> release_C_heap_structures.  Methods won't have method_data unless 
> they're deallocated from the InstanceKlass.  The other paths to 
> deallocate_contents are before the method is called.

I'm not understanding why delete is not used to run the destructor and 
free the memory. Is this memory that is being specially managed?

Thanks,
David

> Tested with tier1 all Oracle platforms, and tier2-6 on linux-x64.
> 
> open webrev at http://cr.openjdk.java.net/~coleenp/2019/8232112.01/webrev
> bug link https://bugs.openjdk.java.net/browse/JDK-8232112
> 
> Thanks,
> Coleen
> 
>