RFR: Improve scheduling and interleaving of SATB processing in mark loop

[Aleksey Shipilev]

On 06/18/2018 01:28 PM, Aleksey Shipilev wrote:
> I can work the whole patch out performance-wise.

Full patch I'm testing:
  http://cr.openjdk.java.net/~shade/shenandoah/satb-interleave/webrev.01/

-Aleksey