--- a/src/hotspot/share/services/lowMemoryDetector.cpp	Thu Apr 25 05:54:54 2019 -0700
+++ b/src/hotspot/share/services/lowMemoryDetector.cpp	Thu Apr 25 10:56:31 2019 -0400
@@ -80,7 +80,7 @@
 // This method could be called from any Java threads
 // and also VMThread.
 void LowMemoryDetector::detect_low_memory() {
-  MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
+  MutexLocker ml(Service_lock, Mutex::_no_safepoint_check_flag);
 
   bool has_pending_requests = false;
   int num_memory_pools = MemoryService::num_memory_pools();
@@ -113,7 +113,7 @@
   }
 
   {
-    MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
+    MutexLocker ml(Service_lock, Mutex::_no_safepoint_check_flag);
 
     MemoryUsage usage = pool->get_memory_usage();
     sensor->set_gauge_sensor_level(usage,
@@ -135,7 +135,7 @@
   }
 
   {
-    MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
+    MutexLocker ml(Service_lock, Mutex::_no_safepoint_check_flag);
 
     MemoryUsage usage = pool->get_last_collection_usage();
     sensor->set_counter_sensor_level(usage, pool->gc_usage_threshold());
@@ -335,7 +335,7 @@
 
   {
     // Holds Service_lock and update the sensor state
-    MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
+    MutexLocker ml(Service_lock, Mutex::_no_safepoint_check_flag);
     assert(_pending_trigger_count > 0, "Must have pending trigger");
     _sensor_on = true;
     _sensor_count += count;
@@ -346,7 +346,7 @@
 void SensorInfo::clear(int count, TRAPS) {
   {
     // Holds Service_lock and update the sensor state
-    MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
+    MutexLocker ml(Service_lock, Mutex::_no_safepoint_check_flag);
     if (_pending_clear_count == 0) {
       // Bail out if we lost a race to set_*_sensor_level() which may have
       // reactivated the sensor in the meantime because it was triggered again.