docs: private int healthCheckFailed() {
          int oldState, newState;
          for (;;) {
              oldState = this.state;
              if ((oldState & ERROR) != ERROR) {
                  newState = oldState | ERROR;
                  UndertowLogger.ROOT_LOGGER.nodeIsInError(jvmRoute);
              } else if ((oldState & ERROR_MASK) == ERROR_MASK) {
                  return ERROR_MASK;
              } else {
                  newState = oldState +1;
              }
              if (stateUpdater.compareAndSet(this, oldState, newState)) {
                  return newState & ERROR_MASK;
              }
          }
      }