RFR: 8069034: gc/g1/TestEagerReclaimHumongousRegionsClearMarkBits.java nightly failure

[Thomas Schatzl]

Hi Stefan,

On Mon, 2015-02-02 at 14:28 +0100, Stefan Johansson wrote:
> Hi Thomas,
> 
> On 2015-02-02 11:15, Thomas Schatzl wrote:
> > Hi all,
> >
> > On Thu, 2015-01-29 at 12:55 +0100, Stefan Johansson wrote:
> >> Hi,
> >>
> >> Please review this fix for:
> >> https://bugs.openjdk.java.net/browse/JDK-8069034
> >>
> >> Webrev:
> >> http://cr.openjdk.java.net/~sjohanss/8069034/hotspot.00/
> >>
> >> Summary:
> >> While looking for humongous objects to reclaim we unconditionally
> >> dirtied cards, some of those might belong to freed regions and if so the
> >> card table verification will fail. The simple fix is to avoid this by
> >> checking that the card belong to live regions before dirtying. A more
> >> robust fix would be to have the iterator avoid returning invalid cards,
> >> but that is a bigger change and I will file an RFE for this.
> > I would prefer if the comment were more detailed in why this check is
> > required, e.g. something like "The remembered set might contain
> > references to already freed region. Filter them out to to avoid failing
> > assertions." or so.
> 
> I changed it to:
> // The remembered set might contain references to already freed
> // regions. Filter out such entries to avoid failing card table
> // verification.

Looks good, thanks.

Thomas