Recompute Ember custom helper on change of a controller property that is passed to the helper

I'm changing the value of a property in my controller and the helper fails to recompute them.

Sample code here:

My template looks like,

    <span>Warning</span>

In my controller,

changeAction: function() {
    let that = this,
        info = that.get("info");
    set(info, "showWarning", true);
}

my helper,

import { helper as buildHelper } from '@ember/component/helper';

export default buildHelper(function(params) {
    let that = this,
        info = that.get("info");
    if(info.showWarning ) {
        return true;
    } else {
        return false
    }
});