从Symfony中的EventListener创建可重用/全局变量

I use an EventListener which checks permissions of Users accessing each controller and log those actions. I now want to add a unique identifier for each call and add it to the log. While that is easy INSIDE the EventListener, is there a way to use the same $var that was created in the EventListener in the Controller that called the EventListener?

Example:

User accesses Controller::Something --> EventListener gets called unique $uid gets created --> use that $uid inside of the controller again.

My EventListener:

public function onKernelController(FilterControllerEvent $event)
{
   $uid = rand();
   ...
   /* Log Action */
   $this->log->writeLog('SOME MESSAGE', __LINE__, 3, $uid);
   ...
}

My Controller:

/**
 * @Route("/admin/_ajax/_saveNewClient", name="saveNewClient")
 */
public function saveNewClientAction(Request $request)
{
    //DO STH
    ...
    /* Log Action */
    $this->get('log')->writeLog(
     'OTHER MESSAGE AFTER EVENTLISTENER', __LINE__, 1, $uid); //$uid from EventListener
    ...
}

you can use session :

$session = new Session();
$session->start();

// set and get session attributes
$session->set('LINE', 'value');
$session->get('LINE');