diff -r 409d4b59e095 -r ed5a590835a4 src/share/vm/services/memBaseline.cpp
--- a/src/share/vm/services/memBaseline.cpp	Tue Apr 30 02:28:42 2013 -0700
+++ b/src/share/vm/services/memBaseline.cpp	Tue Apr 30 09:17:06 2013 -0400
@@ -156,7 +156,8 @@
 // for the safepoint
 void MemBaseline::check_safepoint(JavaThread* thr) {
   if (SafepointSynchronize::is_synchronizing()) {
-    SafepointSynchronize::block(thr);
+    // grab and drop the SR_lock to honor the safepoint protocol
+    MutexLocker ml(thr->SR_lock());
   }
 }