RFR: Parallelize safepoint cleanup

[David Holmes]

On 29/05/2017 8:47 PM, Kim Barrett wrote:
>> On May 29, 2017, at 4:23 AM, Roman Kennke <rkennke at redhat.com> wrote:
>> I implemented this using the following:
>>
>>   if (ParallelSafepointCleanup &&
>> FLAG_IS_DEFAULT(ParallelSafepointCleanupThreads)) {
>>     // This will pick up ParallelGCThreads if set...
>>     FLAG_SET_DEFAULT(ParallelSafepointCleanupThreads,
>> Abstract_VM_Version::parallel_worker_threads());
>>   }
> 
> Just following along, and not presently planning to do a real review, but the
> above caught my eye.  Clients of the VM_Version infrastructure should never
> directly reference Abstract_VM_Version::<anything>, as doing so may bypass
> platform-specific specializations.
> 
> I thought I’d filed a bug about that sort of thing, but apparently that got pushed
> deep onto my todo list.  I’ll go take care of that now.

Beat you to it by six years:

https://bugs.openjdk.java.net/browse/JDK-7041262

That's a pretty sad statement. Fortunately most things in 
Abstract_VM_Version are not overridden.

David