--- old/src/hotspot/share/gc/shenandoah/shenandoahControlThread.cpp	2019-11-21 11:53:07.090883818 +0100
+++ new/src/hotspot/share/gc/shenandoah/shenandoahControlThread.cpp	2019-11-21 11:53:06.834879635 +0100
@@ -593,7 +593,7 @@
 
 void ShenandoahControlThread::pacing_notify_alloc(size_t words) {
   assert(ShenandoahPacing, "should only call when pacing is enabled");
-  Atomic::add(words, &_allocs_seen);
+  Atomic::add(&_allocs_seen, words);
 }
 
 void ShenandoahControlThread::set_forced_counters_update(bool value) {