--- a/src/hotspot/share/jfr/recorder/storage/jfrBuffer.cpp	Fri May 17 15:53:21 2019 +0200
+++ b/src/hotspot/share/jfr/recorder/storage/jfrBuffer.cpp	Fri May 17 16:02:27 2019 +0200
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2011, 2018, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2011, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -54,10 +54,18 @@
   return true;
 }
 
-void JfrBuffer::reinitialize() {
+void JfrBuffer::reinitialize(bool exclusion /* false */) {
   assert(!lease(), "invariant");
   assert(!transient(), "invariant");
   set_pos(start());
+  if (exclusion != excluded()) {
+    // update
+    if (exclusion) {
+      set_excluded();
+    } else {
+      clear_excluded();
+    }
+  }
   clear_retired();
   set_top(start());
 }
@@ -136,6 +144,14 @@
   _identity = NULL;
 }
 
+bool JfrBuffer::acquired_by(const void* id) const {
+  return identity() == id;
+}
+
+bool JfrBuffer::acquired_by_self() const {
+  return acquired_by(Thread::current());
+}
+
 #ifdef ASSERT
 static bool validate_to(const JfrBuffer* const to, size_t size) {
   assert(to != NULL, "invariant");
@@ -153,10 +169,6 @@
   assert(t->top() + size <= t->pos(), "invariant");
   return true;
 }
-
-bool JfrBuffer::acquired_by_self() const {
-  return identity() == Thread::current();
-}
 #endif // ASSERT
 
 void JfrBuffer::move(JfrBuffer* const to, size_t size) {
@@ -183,11 +195,11 @@
   set_concurrent_top(start());
 }
 
-// flags
 enum FLAG {
   RETIRED = 1,
   TRANSIENT = 2,
-  LEASE = 4
+  LEASE = 4,
+  EXCLUDED = 8
 };
 
 bool JfrBuffer::transient() const {
@@ -222,6 +234,22 @@
   assert(!lease(), "invariant");
 }
 
+bool JfrBuffer::excluded() const {
+  return (u1)EXCLUDED == (_flags & (u1)EXCLUDED);
+}
+
+void JfrBuffer::set_excluded() {
+  _flags |= (u1)EXCLUDED;
+  assert(excluded(), "invariant");
+}
+
+void JfrBuffer::clear_excluded() {
+  if (excluded()) {
+    _flags ^= (u1)EXCLUDED;
+  }
+  assert(!excluded(), "invariant");
+}
+
 static u2 load_acquire_flags(const u2* const flags) {
   return OrderAccess::load_acquire(flags);
 }