RFR 8003421: NPG: Move oops out of InstanceKlass into mirror

[Dean Long]

On 5/21/2013 5:24 AM, Coleen Phillimore wrote:
>
> On 05/21/2013 01:12 AM, David Holmes wrote:
>> On 21/05/2013 2:50 PM, Dean Long wrote:
>>> Right, unless there is a way to inject them conditionally.
>>
>> You can inject them conditionally based on the JRE version, but then 
>> why bother moving to the Java level if you will still need the code 
>> in the VM ?
>
It could have removed some code on the JDK side, but it sounds like it's 
not a good idea for java.lang.Class.

dl

> Absolutely. That's why I don't want to move them to the Java level.   
> I'd have to add 90% of the same code and then they'd be available to 
> Java but they're used as much in the VM than in Java. And I think 
> protection_domain shouldn't be visible to the Java code for security 
> reasons.   So I see no point to doing it.
>
>>
>>> On 5/20/2013 9:02 PM, Ioi Lam wrote:
>>>> But if you move these fields into Class.java (in JDK8), then hsx25
>>>> will not run on JDK7 anymore, unless these fields are also added in
>>>> Class.java in JDK7.
>>
>> As I understand it hs25 is already limited in the versions of jdk7 
>> that it can run in.
>
> Yes, I think it still works for now.
>
> Coleen
>>
>> David
>> -----
>>
>>>>
>>>> - Ioi
>>>>
>>>> On 05/20/2013 05:42 PM, Dean Long wrote:
>>>>> It seems like you could take this opportunity to make these declared
>>>>> fields of java.lang.Class,
>>>>> allowing, for example, getProtectionDomain0() to be a simple Java
>>>>> method instead of a native method.
>>>>>
>>>>> dl
>>>>>
>>>>> On 05/20/2013 03:39 PM, Coleen Phillimore wrote:
>>>>>> Summary: Inject protection_domain, signers, init_lock into
>>>>>> java_lang_Class
>>>>>>
>>>>>> Net footprint change is zero except that these fields are in Java
>>>>>> heap rather than metaspace.  This helps a little with InstanceKlass
>>>>>> size which is in fixed size space with UseCompressedKlassPointers.
>>>>>> Included serviceability because there were SA changes to code that I
>>>>>> don't know is used.
>>>>>>
>>>>>> Future work is to remove the signers field and the unused
>>>>>> SetProtectionDomain function.
>>>>>>
>>>>>> open webrev at http://cr.openjdk.java.net/~coleenp/8003421/
>>>>>> bug link at http://bugs.sun.com/view_bug.do?bug_id=8003421
>>>>>>
>>>>>> Tested with vm.quick.testlist, JPRT, jtreg java/security tests and
>>>>>> jck8 tests.
>>>>>>
>>>>>> Thanks,
>>>>>> Coleen
>>>>>
>>>>
>>>
>