RFR: 8204554: JFR TLAB tracing broken after 8202776

[Erik Österlund]

Hi Thomas,

Thanks for the review.

/Erik

On 2018-06-11 11:34, Thomas Schatzl wrote:
> Hi,
>
> On Thu, 2018-06-07 at 16:27 +0200, Erik Österlund wrote:
>> Hi,
>>
>> The recent allocation path modularization (8202776) broke JFR TLAB
>> sampling. This was discovered in tier 5 testing.
>>
>> The problem is that there was previously an early exit TLAB path,
>> that should not run the tracing code when not returning NULL, and a
>> mem_allocate call that should run the tracing code when not
>> returning NULL. However, these paths were joined in a virtual member
>> function, making them look the same to the tracing code, which caused
>> the non-TLAB tracing code to be run on TLAB allocations as well.
>>
>> The solution I propose is to move the TLAB tracing code into the new
>> virtual member function. It seems that whatever GC overrides this
>> code, should also decide what to do about the tracing code there
>> anyway.
>>
>    looks good.
>
> Thomas
>