private void resetArmHook(String rname) {
    LocalRegion r = (LocalRegion) cache.getRegion(rname);
    ((AbstractRegionMap) r.entries).setARMLockTestHook(null);
  }
Cleanup arm lock hook by setting it null
geode-core/src/distributedTest/java/org/apache/geode/internal/cache/ClearTXLockingDUnitTest.java