I used the Objective-C code below to pop a specific ViewController.
for (UIViewController *controller in self.navigationController.
Please use this below code for Swift 3.0:
let viewControllers: [UIViewController] = self.navigationController!.viewControllers as [UIViewController];
for aViewController:UIViewController in viewControllers {
if aViewController.isKind(of: YourViewController.self) {
_ = self.navigationController?.popToViewController(aViewController, animated: true)
}
}