RFR: 8154343: Make SATB related code available to other GCs

[Erik Helin]

On 2016-04-25, Roman Kennke wrote:
> Am Mittwoch, den 20.04.2016, 19:54 +0200 schrieb Roman Kennke:
> > Am Montag, den 18.04.2016, 10:50 -0700 schrieb Jon Masamitsu:
> > > 
> > > 
> > > On 04/18/2016 04:50 AM, Roman Kennke wrote:
> > > > 
> > > > 
> > > > Am Freitag, den 15.04.2016, 14:30 -0700 schrieb Jon Masamitsu:
> > > > > 
> > > > > 
> > > > > On 4/15/2016 12:17 PM, Roman Kennke wrote:
> > > > > > 
> > > > > > 
> > > > > > I just noticed that I made the patch against the jdk9
> > > > > > repository,
> > > > > > instead of jdk9-dev. There was a small change to make to
> > > > > > require_marking()/retain_entry(). The updated webrev is here:
> > > > > > 
> > > > > > http://cr.openjdk.java.net/~rkennke/jdk-8154343/webrev.01/
> > > > > > 
> > > > > > And I also forgot to post a link to the jira entry:
> > > > > > https://bugs.openjdk.java.net/browse/JDK-8154343
> > > > > > 
> > > > > > Please let me know what you think, and if I can commit it.
> > > > > > Thanks!
> > > > > Roman,
> > > > > 
> > > > > You're aware of jprt?  The tool that Oracle uses to build
> > > > > hotspot
> > > > > patches on all platforms,
> > > > > do a minimum amount of testing, and then does the commit?  For
> > > > > shared
> > > > > code
> > > > > such as in your patch, it is always used.  Sorry if I'm stating
> > > > > old
> > > > > news
> > > > > but I wasn't
> > > > > sure what to make of your request to commit (yourself).
> > > > Yes, I am aware, but wasn't sure if it's still used or if
> > > > external
> > > > contributors need to worry about it, because I heard conflicting
> > > > stories about the possibility to commit patches ourself.
> > > If a change is to platform specific code and not shared (I'm
> > > thinking
> > > Zero and Shark), then the pushes can done by the external
> > > contributor.
> > > Please don't quote that as definitive.   It was stated more
> > > precisely
> > > somewhere.  But your change is to share code so does not qualify.
> > > 
> > > > 
> > > > 
> > > > 
> > > > So how would I go about getting a sponsor for a patch like this?
> > > When it's been reviewed (for anything significant by 2 reviewers,
> > > one
> > > of which needs to have Reviewer status as defined by the Bylaws),
> > > ask
> > > for a sponsor.
> 
> Ping! How can we make progress with this change? If there's anything I
> can do to make it easier, please let me know.

Hi Roman,

how does moving ptrQueue.{hpp,cpp} and g1SATBMarkQueue.{hpp,cpp} makes
merging easier for you guys? This code hasn't (sadly) seen much changes
lately, g1SATBMarkQueue.{hpp,cpp} hasn't been changed in the past six
months and there has only been three changes to ptrQueue.{hpp,cpp}
during the same period.

I'm a bit hesitant to move this code to gc/shared, even more when this
is rather old code that is in desperate need of a rewrite.

Thanks,
Erik

> Best regards,
> Roman