RFR(S) 8054368: nsk/jdi/VirtualMachine/exit/exit002 crash with detail tracking on (NMT2)

[David Holmes]

On 14/08/2014 5:54 AM, Zhengyu Gu wrote:
> The crash is caused by debugee exiting process by calling ::exit(),
> which causes C runtime to destroy static object
> (VirtualMemoryTracker::_reserved_regions)  while threads still access it.

Non-trivial static C++ objects plus multi-threading just don't mix.

> The solution is to replace it with pointer type, allocates the object
> during NMT initialization and deallocate it during shutdown.

Looks okay to me.

Thanks,
David

> Bug: https://bugs.openjdk.java.net/browse/JDK-8054368
> Webrev: http://cr.openjdk.java.net/~zgu/8054368/webrev.00/
> <http://cr.openjdk.java.net/%7Ezgu/8054368/webrev.00/>
>
> Test:
>     Ran nsk/jdi/VirtualMachine/exit/exit002 in a loop for 1+ hour on
> Solaris x64, no crash.
>     Without the fix, it crashes within 5 minutes.
>
>
> Thanks,
>
> -Zhengyu
>