RFR(M): 8017317: PPC64 (part 7): cppInterpreter: implement support for biased locking

[Vladimir Kozlov]

Hi Goetz,

On 6/26/13 7:30 AM, Lindenmaier, Goetz wrote:
> Hi,
>
> To use biased locking in our PPC64 VM,we fixed the biased locking implementation
> in the cppInterpreter.  We also added  BiasedLockingStatistic support.

Oracle does not use cppInterpreter and no building and testing are done. 
So we trust you to do testing of these changes.
I glanced on these changes and they look fine to me.

One suggestion I heard from David H. is to move cppInterpreter related 
files (all 6 of them) from interpreter/ directory to separate directory. 
So we can see when changes does not affect our shared code.

> We need an additional ordering operation in revoke_bias() when writing
> the mark.

Why you need ordering only for locked objects in this code? And why here 
at all? This code is executed at safepoint.

thanks,
Vladimir

> The change enables biased locking for ppc64 per default.
> http://cr.openjdk.java.net/~goetz/webrevs/8017317-lock/
>
> Please review and test this change.
>
> Best regards,
>    Goetz
>