RFR (sh/jdk8): Backport 2020-02-28

[Aleksey Shipilev]

On 2/28/20 10:32 PM, Roman Kennke wrote:
> For JDK-8236732, I needed to re-work the PLL special handling
> (jdk8-specific) a little bit, so that it doesn't call
> pending_list_lock() (which does the LRB itself) and then blindly
> following this by another LRB. That is because it would attempt to
> re-enter the evac-oom-scope. Instead it now carefully loads the PLL
> (without its own LRB), and then does almost the same as the LRB, but
> doesn't check evac-in-progress (because we know we must be) and also
> doesn't enter evac-oom-scope (because we already have it).

Ugh. Ugly PLL again. You still better to assert evac-in-progress and evac-oom-scope then?

> Webrev:
> http://cr.openjdk.java.net/~rkennke/backport-shjdk8-2020-02-28/webrev.00/

Otherwise looks good.

-- 
Thanks,
-Aleksey