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

[Patricio Chilano]

On 8/11/20 4:27 PM, Coleen Phillimore wrote:
>
>
> 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.
Thanks for reviewing this Coleen!


Patricio
> 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
>>>
>