src/hotspot/share/runtime/threadSMR.cpp

rev 49294 : imported patch 8199813

*** 26,35 ****
--- 26,36 ----
  #include "logging/logStream.hpp"
  #include "memory/allocation.inline.hpp"
  #include "runtime/jniHandles.inline.hpp"
  #include "runtime/thread.inline.hpp"
  #include "runtime/threadSMR.inline.hpp"
+ #include "runtime/vm_operations.hpp"
  #include "services/threadService.hpp"
  #include "utilities/copy.hpp"
  #include "utilities/globalDefinitions.hpp"
  #include "utilities/resourceHash.hpp"
  #include "utilities/vmError.hpp"
*** 467,476 ****
--- 468,487 ----
    return new_list;
  }
  
  ThreadsListHandle::ThreadsListHandle(Thread *self) : _list(ThreadsSMRSupport::acquire_stable_list(self, /* is_ThreadsListSetter */ false)), _self(self) {
    assert(self == Thread::current(), "sanity check");
+   // Threads::threads_do() is used by the Thread-SMR protocol to visit all
+   // Threads in the system which ensures the safety of the ThreadsList
+   // managed by this ThreadsListHandle, but JavaThreads that are not on
+   // the Threads list cannot be included in that visit. The JavaThread that
+   // calls Threads::destroy_vm() is exempt from this check because it has
+   // to logically exit as part of the shutdown procedure. This is safe
+   // because VM_Exit::_shutdown_thread is not set until after the VMThread
+   // has started the final safepoint which holds the Threads_lock for the
+   // remainder of the VM's life.
+   assert(!self->is_Java_thread() || self == VM_Exit::shutdown_thread() || (((JavaThread*)self)->on_thread_list() && !((JavaThread*)self)->is_terminated()), "JavaThread must be on the Threads list to use a ThreadsListHandle");
    if (EnableThreadSMRStatistics) {
      _timer.start();
    }
  }