review for 7029167: add support for conditional card marks

[Vladimir Kozlov]

Tom,

what about arraycopy stubs?

Vladimir

Tom Rodriguez wrote:
> http://cr.openjdk.java.net/~never/7029167
> 
> 7029167: add support for conditional card marks
> Reviewed-by:
> 
> Repeated updates to the card table can be a source of contention on
> multiprocessor machines that can greatly inhibit scalability.  This
> adds support in C2 for conditional card marks.  Tested with jbb and
> CTW.  At some point this should be turned on automatically when multi
> socket machines are detected but that's covered under another bug as
> is C1 support.
>