[11u] RFR: Backport JDK-8209657: Refactor filemap.hpp to simplify integration with Serviceability Agent

[Langer, Christoph]

Hi,

for these issues [0] - [3] I'd like to take a similar path as with JDK-8185525.

These issues can't just be considered as must-have bugfixes, so the question is whether the stability risk is justifiable. I would feel somewhat comfortable to approve these fixes early in the 11.0.7 release cycle, though, since I've seen them work without regressions in our test system.

So, please raise objections until next Friday (29th of November) - otherwise I'd then go and approve them.

Thanks
Christoph

[0] https://bugs.openjdk.java.net/browse/JDK-8209385 
[1] https://bugs.openjdk.java.net/browse/JDK-8209389 
[2] https://bugs.openjdk.java.net/browse/JDK-8209657 
[3] https://bugs.openjdk.java.net/browse/JDK-8209826

> -----Original Message-----
> From: Jiangli Zhou <jianglizhou at google.com>
> Sent: Donnerstag, 7. November 2019 02:36
> To: jdk-updates-dev at openjdk.java.net
> Cc: Langer, Christoph <christoph.langer at sap.com>; Andrew Haley
> <aph at redhat.com>
> Subject: Re: [11u] RFR: Backport JDK-8209657: Refactor filemap.hpp to
> simplify integration with Serviceability Agent
> 
> Hi,
> 
> As suggested by Andrew Haley and Christoph, I'd like to take a survey
> to see if there is any interest/needs for backporting the following
> minor CDS fixes to JDK 11u.
> 
> https://bugs.openjdk.java.net/browse/JDK-8209385
> https://bugs.openjdk.java.net/browse/JDK-8209389
> https://bugs.openjdk.java.net/browse/JDK-8209657
> https://bugs.openjdk.java.net/browse/JDK-8209826
> 
> Since stability is the highest priority for update release, it would
> only be reasonable for the additional CDS minor bug fix/enhancement
> backports if the community's interest/demand is high enough. Thanks!
> 
> Best,
> 
> Jiangli
> 
> 
> On Thu, Oct 10, 2019 at 7:36 AM Jiangli Zhou <jianglizhou at google.com>
> wrote:
> >
> > Thank you so much, Christoph! Will wait.
> >
> > Best regards,
> > Jiangli
> >
> > On Thu, Oct 10, 2019 at 3:14 AM Langer, Christoph
> > <christoph.langer at sap.com> wrote:
> > >
> > > Hi Jiangli,
> > >
> > > the webrev looks good to me and I ran it together with the other CDS
> related backports that you requested through our test system. We didn't see
> regressions.
> > >
> > > Please allow some time to consult with Andrew on whether to approve
> the backports for pushing.
> > >
> > > Thanks
> > > Christoph
> > >
> > > > -----Original Message-----
> > > > From: hotspot-runtime-dev <hotspot-runtime-dev-
> > > > bounces at openjdk.java.net> On Behalf Of Jiangli Zhou
> > > > Sent: Donnerstag, 3. Oktober 2019 22:42
> > > > To: jdk-updates-dev at openjdk.java.net; hotspot-runtime-dev
> <hotspot-
> > > > runtime-dev at openjdk.java.net>
> > > > Subject: [11u] RFR: Backport JDK-8209657: Refactor filemap.hpp to
> simplify
> > > > integration with Serviceability Agent
> > > >
> > > > Please review the backport of JDK-8209657: Refactor filemap.hpp to
> > > > simplify integration with Serviceability Agent.
> > > >
> > > > webrev: http://cr.openjdk.java.net/~jiangli/backport-
> 8209657/webrev.00/
> > > >
> > > > The backport applied 99% cleanly. The only manual part involved was to
> > > > apply the following diff in filemap.hpp:
> > > >
> > > >  311
> > > >  312   CDSFileMapRegion* space_at(int i) {
> > > >  313     assert(i >= 0 && i < NUM_CDS_REGIONS, "invalid region");
> > > >  314     return &_header->_space[i];
> > > >  315   }
> > > >  316 };
> > > >
> > > > The backport was done with the intention to downporting additional
> CDS
> > > > bug fixes and improvements that are depending on this one.
> > > >
> > > > Best,
> > > >
> > > > Jiangli