How to display total views of all posts of one category?

<?php
    $QUERY = new Wp_query(array( 
        'post_type' => 'post_type_here',
        'category_name' => 'category_name_here',
        // you can use cat id ...
    ));
    $counter = 0;
    while( $QUERY->have_posts() ) : $QUERY->the_post();
        $views = absint( getPostViews( $post->ID ) );
        $counter += $views;
    endwhile; wp_reset_postdata();
    echo $counter;

?>

getPostViews() and setPostViews :

function getPostViews( $postID ){

    $count_key = 'post_views_count';
    $count = get_post_meta($postID, $count_key, true);
    if($count==''){
        delete_post_meta($postID, $count_key);
        add_post_meta($postID, $count_key, '0');
        return "0";
    }
    return $count;
}


function setPostViews( $postID ) {

    $count_key = 'post_views_count';
    $count = get_post_meta($postID, $count_key, true);
    if($count==''){
        $count = 0;
        delete_post_meta($postID, $count_key);
        add_post_meta($postID, $count_key, '0');
    }else{
        $count++;
        update_post_meta($postID, $count_key, $count);
    }

}