8293922: Extend barrier-less Java thread transitions to native transitions

Reviewed-by: mdoerr, pchilanomate, dcubed

Author: robehn

src/hotspot/share/runtime/interfaceSupport.inline.hpp

@@ -29,6 +29,7 @@
 // No interfaceSupport.hpp
 
 #include "gc/shared/gc_globals.hpp"
+#include "runtime/globals.hpp"
 #include "runtime/handles.inline.hpp"
 #include "runtime/javaThread.inline.hpp"
 #include "runtime/mutexLocker.hpp"
@@ -97,7 +98,11 @@ class ThreadStateTransition : public StackObj {
     assert(to == _thread_in_vm || to == _thread_in_Java, "invalid transition");
     assert(!thread->has_last_Java_frame() || thread->frame_anchor()->walkable(), "Unwalkable stack in native transition");
 
-    thread->set_thread_state_fence(_thread_in_vm);
+    if (!UseSystemMemoryBarrier) {
+      thread->set_thread_state_fence(_thread_in_vm);
+    } else {
+      thread->set_thread_state(_thread_in_vm);
+    }
     SafepointMechanism::process_if_requested_with_exit_check(thread, to != _thread_in_Java ? false : check_asyncs);
     thread->set_thread_state(to);
   }

src/hotspot/share/runtime/javaThread.inline.hpp

@@ -145,9 +145,9 @@ inline JavaThreadState JavaThread::thread_state() const    {
 #if defined(PPC64) || defined (AARCH64) || defined(RISCV64)
   // Use membars when accessing volatile _thread_state. See
   // Threads::create_vm() for size checks.
-  return (JavaThreadState) Atomic::load_acquire((volatile jint*)&_thread_state);
+  return Atomic::load_acquire(&_thread_state);
 #else
-  return _thread_state;
+  return Atomic::load(&_thread_state);
 #endif
 }
 
@@ -157,9 +157,9 @@ inline void JavaThread::set_thread_state(JavaThreadState s) {
 #if defined(PPC64) || defined (AARCH64) || defined(RISCV64)
   // Use membars when accessing volatile _thread_state. See
   // Threads::create_vm() for size checks.
-  Atomic::release_store((volatile jint*)&_thread_state, (jint)s);
+  Atomic::release_store(&_thread_state, s);
 #else
-  _thread_state = s;
+  Atomic::store(&_thread_state, s);
 #endif
 }