--- a/hotspot/src/share/vm/memory/iterator.cpp	Tue Sep 15 11:09:34 2009 -0700
+++ b/hotspot/src/share/vm/memory/iterator.cpp	Tue Sep 15 21:53:47 2009 -0700
@@ -32,3 +32,42 @@
 void VoidClosure::do_void() {
   ShouldNotCallThis();
 }
+
+MarkingCodeBlobClosure::MarkScope::MarkScope(bool activate)
+  : _active(activate)
+{
+  if (_active)  nmethod::oops_do_marking_prologue();
+}
+
+MarkingCodeBlobClosure::MarkScope::~MarkScope() {
+  if (_active)  nmethod::oops_do_marking_epilogue();
+}
+
+void MarkingCodeBlobClosure::do_code_blob(CodeBlob* cb) {
+  if (!cb->is_nmethod())  return;
+  nmethod* nm = (nmethod*) cb;
+  if (!nm->test_set_oops_do_mark()) {
+    NOT_PRODUCT(if (TraceScavenge)  nm->print_on(tty, "oops_do, 1st visit\n"));
+    do_newly_marked_nmethod(nm);
+  } else {
+    NOT_PRODUCT(if (TraceScavenge)  nm->print_on(tty, "oops_do, skipped on 2nd visit\n"));
+  }
+}
+
+void CodeBlobToOopClosure::do_newly_marked_nmethod(CodeBlob* cb) {
+  cb->oops_do(_cl);
+}
+
+void CodeBlobToOopClosure::do_code_blob(CodeBlob* cb) {
+  if (!_do_marking) {
+    NOT_PRODUCT(if (TraceScavenge && Verbose && cb->is_nmethod())  ((nmethod*)cb)->print_on(tty, "oops_do, unmarked visit\n"));
+    // This assert won't work, since there are lots of mini-passes
+    // (mostly in debug mode) that co-exist with marking phases.
+    //assert(!(cb->is_nmethod() && ((nmethod*)cb)->test_oops_do_mark()), "found marked nmethod during mark-free phase");
+    cb->oops_do(_cl);
+  } else {
+    MarkingCodeBlobClosure::do_code_blob(cb);
+  }
+}
+
+