RFR: 8215097: Do not create NonJavaThreads before BarrierSet

[Per Liden]

Hi,

On 12/09/2018 11:05 PM, David Holmes wrote:
> Hi Kim,
> 
> Didn't realize you were going to tackle this so soon. I was just ironing 
> out the wrinkles in 8214097 before sending it for review later today. :)
> 
> On 9/12/2018 6:30 pm, Kim Barrett wrote:
>> Please review this change to move the construction of some work gang
>> threads by G1 and CMS to after they've created the barrier set.  This
>> allows the removal of some bootstrapping code needed to support that
>> construction order.  There isn't any requirement for the old order,
>> it seems to just be a historical artifact.
>>
>> CR:
>> https://bugs.openjdk.java.net/browse/JDK-8215097
>>
>> Webrev:
>> http://cr.openjdk.java.net/~kbarrett/8215097/open.00/
> 
> Moving the GC thread creation out of the heap constructor into the heap 
> initialize function seems quite reasonable. Does ZGC already defer the 
> thread creation? Will this impact the merge of Shenandoah?

ZGC creates the workers in the constructor, and frankly I don't think we 
want to change that, unless there's some very good reason. I haven't 
checked Shenandoah.

cheers,
Per

> 
> Everything else seems fine. (I'll be reworking the BarrierSet creation 
> assertion as part of 8214097.)
> 
> Thanks,
> David
> 
>> Testing:
>> mach5 tier1-5
>>