RFR 8251118: BiasedLocking::preserve_marks should not have a HandleMark

[Coleen Phillimore]

On 8/11/20 3:11 PM, Harold Seigel wrote:
> Hi Patricio,
>
> The fix looks good.  Could you also add a test based on the failure 
> discussed in the bug description?

+1.  Thank you for careful examination of the callers.
Coleen
>
> Thanks, Harold
>
> On 8/11/2020 2:11 PM, Patricio Chilano wrote:
>> Hi all,
>>
>> Please review the following small fix which involves removing the 
>> added HandleMark in BiasedLocking::preserve_marks():
>>
>> Bug: https://bugs.openjdk.java.net/browse/JDK-8251118
>> Webrev: http://cr.openjdk.java.net/~pchilanomate/8251118/v1/webrev/
>>
>> I've inspected the callers of BiasedLocking::preserve_marks() and 
>> they all have an assert that the current thread is the VMThread. 
>> Since the VMThread creates a HandleMark object before executing a VM 
>> operation the extra HandleMark added in 8249192 is not needed.
>> I've run tiers1-3 in mach5 with -XX:+UseBiasedLocking and without the 
>> patch I get several crashes in BiasedLocking::restore_marks(). With 
>> the patch tests completed successfully.
>>
>> Thanks,
>> Patricio
>>