RFR 8249217: Unexpected StackOverflowError in "process reaper" thread still happens

[Martin Buchholz]

Roger: You're absolutely right!  I should have looked.

On Wed, Jul 22, 2020 at 5:25 PM Roger Riggs <Roger.Riggs at oracle.com> wrote:
>
> Hi Martin,
>
> That's a good idea, but unless I miss your point, there is no Reaper class,
> only a lambda that is used as to create the Executor for the reaper
> thread pool.
>
> Do you mean to put it before or after lines 91-93?  [1]
>
> Thanks, Roger
>
> [1]
> http://cr.openjdk.java.net/~rriggs/webrev-stackoverflow-8249217/src/java.base/share/classes/java/lang/ProcessHandleImpl.java.sdiff.html
>
>
> On 7/22/20 8:06 PM, Martin Buchholz wrote:
> > Looks good.
> >
> > I might move the static class preloading into a static method of the
> > reaper thread class, to make it clearly the responsibility of the
> > reaper thread class to enumerate and pre-load its dependencies.
> >
> > On Wed, Jul 22, 2020 at 7:59 AM Peter Levart <peter.levart at gmail.com> wrote:
> >> Hi Roger,
> >>
> >>
> >> I don't think resolving the ConcurrentHashMap.class ensures
> >> initialization of the class. Just loading. But I think CHM is already
> >> initialized at that time as it is used in ClassLoader to maintain class
> >> loading locks (per class name).
> >>
> >>
> >> Regards, Peter
> >>
> >>
> >> On 7/22/20 4:51 PM, Roger Riggs wrote:
> >>> Please review a change to the Process reaper thread initialization to
> >>> preemptively
> >>> make sure classes ThreadLocalRandom and ConcurrentHashMap are
> >>> initialized.
> >>>  From the stack overflow failures, it seems that the classes have not
> >>> been initialized
> >>> before they are used during processing the termination of a process.
> >>> When the initialization is performed on the smaller reaper stack, it
> >>> occasionally
> >>> exceeds the available stack.
> >>>
> >>> As an aid to diagnostics,
> >>> -XX:AbortVMOnException=java.lang.StackOverflowError
> >>> is added to TestHumongousNonArrayAllocation that has failed
> >>> intermittently.
> >>> If the problem happens again it will produce an hs_error file with
> >>> useful details
> >>> and will otherwise not change the test behavior.
> >>>
> >>> Webrev:
> >>> http://cr.openjdk.java.net/~rriggs/webrev-stackoverflow-8249217/
> >>>
> >>> Issue:
> >>>    https://bugs.openjdk.java.net/browse/JDK-8249217
> >>>
> >>> Thanks, Roger
> >>>
>