RFR(s): 8029162: G1: Shared SATB queue never enabled

[Thomas Schatzl]

Hi Per,

On Fri, 2013-11-29 at 09:47 +0100, Per Liden wrote:
> Hi Mikael,
> 
> On 2013-11-29 08:59, Mikael Gerdin wrote:
> > Per,
> >
> > On Thursday 28 November 2013 17.49.53 Per Liden wrote:
> >> Summary: When activating/deactivating the G1 pre-barrier all SATB queues
> >> are looped through and have their active state set accordingly. There is
> >> one queue per Java thread and a shared queue for all non-Java threads.
> >> The loop done to set the active state of all queues forgets to set the
> >> active state on the shared queue. I suspect this was missed because the
> >> logic in SATBMarkQueueSet::set_active_all_threads() is mixed with quite
> >> a bit of verification code. This patch also moves this verification code
> >> out into a separate function.
> >>
> >> Testing done: jprt, kitchensink (10 hours), gcbasher (10 hours)
> >>
> >> http://cr.openjdk.java.net/~pliden/8029162/webrev.0/
> > The change looks good to me.
> 
> Thanks for reviewing!
> 
> >
> > Since this change enables the bug in JDK-8029255 I assume that these changes
> > must be applied together?
> 
> Not necessarily applied together, but yes, JDK-892255 needs to be 
> applied first. That patch is not dependent on this fix.

Please strongly consider to push them in the same changeset (you can set
two CRs in the header). This avoids somebody ever checking out/using a
bugged version.

Thanks,
Thomas