getting blank page after redirect in wordpress

my function is attached to init action hook, and the function redirects to the same page at the end then uses exit;

add_action('init', 'login_process');
function login_process(){
//login code
wp_redirect(get_permalink());
             exit;
}

If i refresh second time then the page is comming up, also if i don't use exit; then everything is working fine, but wordpress codex says we need to almost always use exit; after wp_redirect. Also if i use home_url() instead of get_permalink() then it is also working, but i want the user to stay in the same page. Basically i'm trying to use a front end login system.