hg: jdk/sandbox: 8213231: ThreadSnapshot::_threadObj can become stale

[chris.hegarty at oracle.com]

Changeset: b2d1c3b0bd31
Author:    ehelin
Date:      2019-01-23 13:40 +0100
URL:       http://hg.openjdk.java.net/jdk/sandbox/rev/b2d1c3b0bd31

8213231: ThreadSnapshot::_threadObj can become stale
Reviewed-by: dcubed, dholmes, rehn

! src/hotspot/share/runtime/vmOperations.cpp
! src/hotspot/share/runtime/vmOperations.hpp
! src/hotspot/share/services/management.cpp
! src/hotspot/share/services/threadService.cpp
! src/hotspot/share/services/threadService.hpp