RFR: 8190408: Run G1CMRemarkTask with the appropriate amount of threads instead of starting up everyone

[Thomas Schatzl]

Hi,

On Tue, 2017-11-21 at 15:56 +0100, Leo Korinth wrote:
> Hi,
> 
> Removing an if statement. The if-statement did safeguard that the
> worker_id was always within the number of active tasks in _cm.
> 
> However the active number of tasks in _cm is set directly before the
> remark task is created (set_concurrency_and_phase()). The value is
> taken from the work gang (g1h->workers()->active_workers()). Thus, as
> set_concurrency*() is not called during the actual remarking, the
> size
> of the work-gang will be in sync with the _cm->active_tasks() -- at
> least during the remark phase.
> 
> The code becomes somewhat easier to read, and hopefully one does not
> get confused that we have too many threads running.
> 
> Bug:
> https://bugs.openjdk.java.net/browse/JDK-8190408
> 
> Webrev:
> http://cr.openjdk.java.net/~lkorinth/8190408/00/
> 

Looks good.

Thanks,
  Thomas