RFR (M): 8165857: CMS _overflow_list is missing volatile qualifiers

[Kim Barrett]

> On Sep 26, 2016, at 11:37 AM, Erik Österlund <erik.osterlund at oracle.com> wrote:
> Yes it sure will handle that. Updated webrev of the minimalist version:
> http://cr.openjdk.java.net/~eosterlund/8165857/webrev.01_v2/

Looks good.

>> That's not what I had in mind.  Rather, I was suggesting changing
>> locals like observed_overflow_list &etc to be "oopDesc*" rather than
>> "oop", so there are no conversions (implicit or explicit).
>> 
>> I have a mild preference for explicit oopDesc* rather than implicit
>> oop conversions here.  I wonder what other reviewers might have to
>> say.
>> 
>> 
> 
> Okay, I tried that idea, here is the result:
> http://cr.openjdk.java.net/~eosterlund/8165857/webrev.03_v2/
> 
> I'm not sure if this is a huge improvement in not spreading too much compared to the HeapWord version.
> What do you think?

That’s more of a change than I was thinking, but regardless, I’m now agreeing that
this direction (regardless of precise details) doesn’t really look like an improvement
on the minimalst version.  Thanks for your patience in trying them out.