RFR: 8234010: ZGC: Change ZResurrection to use Atomic::load/store

[Stefan Karlsson]

Thanks, Erik.

StefanK

On 2019-11-22 12:08, erik.osterlund at oracle.com wrote:
> Hi Stefan,
> 
> Looks good.
> 
> Thanks,
> /Erik
> 
> On 11/21/19 2:24 PM, Stefan Karlsson wrote:
>> Hi all,
>>
>> Please review this patch to change ZResurrection to use Atomic::load 
>> and Atomic::store.
>>
>> https://cr.openjdk.java.net/~stefank/8234010/webrev.01/
>> https://bugs.openjdk.java.net/browse/JDK-8234010
>>
>> Previously, ZResurrection::is_blocked() and ZResurrection::unblock() 
>> used loadload and storestore barriers to synchronize between the GC 
>> and mutator load barriers.
>>
>> JDK-8230661 changed so that we always perform a handshake before the 
>> ZResurrection::unblock() call.
>>
>> After that change we can rely on the handshake to perform the 
>> necessary synchronization, and we can change the implementation to use 
>> Atomic::load and Atomic::store.
>>
>> Tested with tier1-7
>>
>> Thanks,
>> StefanK
>