diff -r a5f5e680ea32 -r ec7d6d8effc7 src/hotspot/share/jfr/recorder/storage/jfrMemorySpace.inline.hpp
--- a/src/hotspot/share/jfr/recorder/storage/jfrMemorySpace.inline.hpp	Tue May 21 13:06:52 2019 -0400
+++ b/src/hotspot/share/jfr/recorder/storage/jfrMemorySpace.inline.hpp	Tue May 21 20:53:27 2019 +0200
@@ -346,19 +346,19 @@
 template <typename Mspace>
 inline bool ReleaseOp<Mspace>::process(typename Mspace::Type* t) {
   assert(t != NULL, "invariant");
-  if (t->retired() || t->try_acquire(_thread)) {
-    if (t->transient()) {
-      if (_release_full) {
-        mspace_release_full_critical(t, _mspace);
-      } else {
-        mspace_release_free_critical(t, _mspace);
-      }
-      return true;
+  // assumes some means of exclusive access to t
+  if (t->transient()) {
+    if (_release_full) {
+      mspace_release_full_critical(t, _mspace);
+    } else {
+      mspace_release_free_critical(t, _mspace);
     }
-    t->reinitialize();
-    assert(t->empty(), "invariant");
-    t->release(); // publish
+    return true;
   }
+  t->reinitialize();
+  assert(t->empty(), "invariant");
+  assert(!t->retired(), "invariant");
+  t->release(); // publish
   return true;
 }