--- old/src/hotspot/share/runtime/objectMonitor.cpp	2018-09-17 23:29:49.035745033 -0700
+++ new/src/hotspot/share/runtime/objectMonitor.cpp	2018-09-17 23:29:48.823745041 -0700
@@ -103,7 +103,6 @@
 
 int ObjectMonitor::Knob_SpinLimit    = 5000;    // derived by an external tool -
 
-static int Knob_MaxSpinners         = -1;      // Should be a function of # CPUs
 static int Knob_Bonus               = 100;     // spin success bonus
 static int Knob_BonusB              = 100;     // spin success bonus
 static int Knob_Penalty             = 200;     // spin failure penalty
@@ -1333,12 +1332,6 @@
   THROW_MSG(vmSymbols::java_lang_IllegalMonitorStateException(), "current thread not owner");
 }
 
-static int Adjust(volatile int * adr, int dx) {
-  int v;
-  for (v = *adr; Atomic::cmpxchg(v + dx, adr, v) != v; v = *adr) /* empty */;
-  return v;
-}
-
 static void post_monitor_wait_event(EventJavaMonitorWait* event,
                                     ObjectMonitor* monitor,
                                     jlong notifier_tid,
@@ -1845,15 +1838,6 @@
     return 0;
   }
 
-  int MaxSpin = Knob_MaxSpinners;
-  if (MaxSpin >= 0) {
-    if (_Spinner > MaxSpin) {
-      return 0;
-    }
-    // Slightly racy, but benign ...
-    Adjust(&_Spinner, 1);
-  }
-
   // We're good to spin ... spin ingress.
   // CONSIDER: use Prefetch::write() to avoid RTS->RTO upgrades
   // when preparing to LD...CAS _owner, etc and the CAS is likely
@@ -1907,7 +1891,6 @@
         if (_succ == Self) {
           _succ = NULL;
         }
-        if (MaxSpin > 0) Adjust(&_Spinner, -1);
 
         // Increase _SpinDuration :
         // The spin was successful (profitable) so we tend toward
@@ -1966,7 +1949,6 @@
   }
 
  Abort:
-  if (MaxSpin >= 0) Adjust(&_Spinner, -1);
   if (_succ == Self) {
     _succ = NULL;
     // Invariant: after setting succ=null a contending thread