RFR: 8200429: Adjust object pinning interface on CollectedHeap

[Roman Kennke]

Am 03.04.2018 um 10:37 schrieb Per Liden:
> On 04/03/2018 10:27 AM, Roman Kennke wrote:
>> Am 03.04.2018 um 08:42 schrieb Per Liden:
>>> The recent additions to CollectedHeap to support object pinning didn't
>>> quite fit the bill for what the Shenandoah folks had in mind. Instead of
>>> having CollectedHeap::pin_obejct/unpin_object grab/release the GCLocker
>>> when object pinning is not supported, we add a
>>> CollectedHeap::supports_obejct_pinning() and let the caller take the
>>> appropriate action based on the response.
>>>
>>> Bug: https://bugs.openjdk.java.net/browse/JDK-8200429
>>> Webrev: http://cr.openjdk.java.net/~pliden/8200429/webrev.0
>>>
>>> /Per
>>
>> Looks good to me. Thank you!
> 
> Thanks for reviewing Roman!
> 
> Do you or Zhengyu plan on upstreaming a version of the patch you linked
> to in the other mail thread, to support object pinning with
> JavaCritical_? It seems that patch would complete the overall object
> pinning story for HotSpot and would be useful for other GCs as well (at
> least G1 and ZGC).

Yes, definitely. Zhengyu is working on it. We want to give it a little
bit of baking in Shenandoah land, and then upstream it soon.

https://bugs.openjdk.java.net/browse/JDK-8199868

Thanks, Roman