RFR(s): 8228758: assert(_no_handle_mark_nesting == 0) failed: allocating handle inside NoHandleMark

[Daniel D. Daugherty]

On 9/4/19 5:03 AM, Robbin Ehn wrote:
> Hi Dan,
>
> On 9/3/19 10:38 PM, Daniel D. Daugherty wrote:
<snip>
>
>>
>> In any case, I'm going to hold off on reviewing the code since I think
>> you're still considering making changes based on David's last set of
>> comments...
>
> I think David is okay with current patch.

Okay, I'll loop back around and review this in a little bit.

Dan


>
> Thanks, Robbin
>
>>
>> Dan
>>
>>
>>
>>>
>>>>
>>>>> This changes the polling model a bit and we have not proper look 
>>>>> at this.
>>>>> Maybe we should add the constraints to the poll and to find any 
>>>>> potential
>>>>> troublesome polls.
>>>>
>>>> I'm not sure how we would discover the problems until we have a 
>>>> handshake that executes some code that violates a constraint. The 
>>>> constraints themselves are not obvious. Subsystems do not clearly 
>>>> identify themselves as being reentrant or not - most things are not 
>>>> reentrant by their nature.
>>>
>>> As we do with safepoints, NoSafepointVerifier (since it covers both 
>>> cases).
>>>
>>> /Robbin
>>>
>>>>
>>>> Cheers,
>>>> David
>>>>
>>>>> Thanks, Robbin
>>>>>
>>>>>>
>>>>>> Thanks,
>>>>>> David
>>>>>> -----
>>>>>>
>>>>>>>
>>>>>>> Thanks, Robbin
>>>>>>>
>>>>>>> Some extra words about NoHandleMark:
>>>>>>> I believe NoHandleMark should be removed.
>>>>>>> In the LEAF case, there is no point in creating a Handle within a
>>>>>>> NoSafepointVerifier, since we don't safepoint.
>>>>>>> The other usecase seems to be, I'm in java don't do VM things, 
>>>>>>> and someone tried
>>>>>>> to protected that with a NoHandleMark. There many ways to create 
>>>>>>> a much more
>>>>>>> robust check for that.
>>>>>>> But a discussion for another time.
>>>>>>>
>>>>>>>
>>>>>>>>
>>>>>>>> Thanks,
>>>>>>>> David
>>>>>>>>
>>>>>>>>> Issue:
>>>>>>>>> https://bugs.openjdk.java.net/browse/JDK-8228758
>>>>>>>>>
>>>>>>>>> Changeset:
>>>>>>>>> http://cr.openjdk.java.net/~rehn/8228758/webrev/
>>>>>>>>>
>>>>>>>>> Passes t1-3 (and performance benchmarks)
>>>>>>>>>
>>>>>>>>> Thanks, Robbin
>>