RFR: 8166811: Missing memory fences between memory allocation and refinement
thomas.schatzl at oracle.com
Thu Nov 17 11:31:38 UTC 2016
On Wed, 2016-11-16 at 13:02 -0500, Kim Barrett wrote:
> > On Nov 16, 2016, at 4:06 AM, Thomas Schatzl <thomas.schatzl at oracle.
> > com> wrote:
> > Hi Kim,
> > On Tue, 2016-11-15 at 19:00 -0500, Kim Barrett wrote:
> > >
> > > I've updated some comments to mention that external
> > > synchronization.
> > 581 // The region could be young. Cards for young regions are
> > set
> > to
> > 582 // g1_young_gen, so the post-barrier will filter them
> > out. However,
> > 583 // that marking is performed concurrently. A write to a
> > young
> > 584 // object could occur before the card has been marked young,
> > slipping
> > 585 // past the filter.
> > I would prefer if the text would not change terminology for the
> > same
> > thing mid-paragraph, from "setting" to "marking". The advantage of
> > it
> > reading better seems to be smaller than the potential confusion.
> // The region could be young. Cards for young regions are
> // distinctly marked (set to g1_young_gen), so the post-barrier
> // filter them out. However, that marking is performed
> // concurrently. A write to a young object could occur before the
> // card has been marked young, slipping past the filter.
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