Merging BSDPort into HotSpot mainline

[Kurt Miller]

On Wednesday 03 August 2011 01:41:01 am Greg Lewis wrote:
> On Tue, Aug 02, 2011 at 05:18:17PM -0400, Kurt Miller wrote:
> > On Tuesday 02 August 2011 08:47:39 am Tom Rodriguez wrote:
> > > What are the UseMembar changes about?  They are fine, I'm curious why they are needed.  I believe !UseMembar is more efficient.
> > 
> > In the 1.5 update time-frame Sun was working on changing UseMembar from default true to false. When I intergrated this change into FreeBSD's port we started hitting intermittant segfaults that I debugged and traced back to the UseMembar setting change. Since releasing stable certified binaries quickly was one of the goals, I reverted the UseMembar default back to true instead of taking time to find the root cause. More details can be found in the freebsd-port thread below.
> > 
> > http://markmail.org/message/rigdtb5heiliutec
> > 
> > IIRC, when I worked on porting BSD hotspot support to 1.6 I tried setting UseMembar default to off/false and it still caused intermittant segfaults. Although, I don't recall if I checked this again with OpenJDK7 on FreeBSD SMP systems.
> 
> Do we have a test case that shows this up?  I have a FreeBSD SMP system I
> can run it on.

Hi Greg,

Refreshing my memory by reading the freebsd-java list for this time-frame
and I see that it was rather easy to reproduce on SMP hardware. Reports
included using tomcat, netbeans and in one case 'java -version'. Here's the
search I used:

http://markmail.org/search/list:org%2Efreebsd%2Efreebsd-java+sigbus+diablo+1%2E5%2E0_06

Thanks,
-Kurt