RFR: Improve abstraction for runtime allocations

[Roman Kennke]

Am 14.05.2018 um 11:12 schrieb Aleksey Shipilev:
> On 05/13/2018 06:45 PM, Roman Kennke wrote:
>> This rebases the patch on top of the PLAB change. It basically reverts
>> some changes in plab that I needed to do there:
>>
>> Diff:
>> http://cr.openjdk.java.net/~rkennke/allocations-rt/webrev.01.diff/
>> Full:
>> http://cr.openjdk.java.net/~rkennke/allocations-rt/webrev.01/
> 
> The patch looks good.
> 
> But the whole lot of reshuffling in shared code unnerves me. In my mind, it feels safer to do the
> mem_allocate rework in upstream, make sure upstream does not break with it, and then pick it up from
> there. Otherwise, we are risking investing into some code shape that would be flat-out rejected
> upstream, and we would have to redo it again.

OK, let me just do it upstream and then trickle down.

Roman