Re: [PATCH 5/6] NLM: Convert lockd to use kthreads

From: Christoph Hellwig
Date: Wed Jan 09 2008 - 12:45:25 EST


On Tue, Jan 08, 2008 at 02:33:17PM -0500, Jeff Layton wrote:
> - struct svc_serv * serv;
> - int error = 0;
> + struct svc_serv *serv;
> + struct svc_rqst *rqstp;
> + int error = 0;
>
> mutex_lock(&nlmsvc_mutex);
> /*
> * Check whether we're already up and running.
> */
> - if (nlmsvc_pid) {
> + if (nlmsvc_task) {
> if (proto)
> error = make_socks(nlmsvc_serv, proto);

While equivalent I think it would be clener to check for nlmsvc_serv
above as that'swhat we're passing to make_socks. But I think the whole
of lockd_up could use a little makeover, but that's for later.

> void
> lockd_down(void)
> {
> mutex_lock(&nlmsvc_mutex);
> if (nlmsvc_users) {
> if (--nlmsvc_users)
> goto out;
> + } else {
> + printk(KERN_ERR "lockd_down: no users! task=%p\n",
> + nlmsvc_task);
> + BUG();
> }
> + if (!nlmsvc_task) {
> + printk(KERN_ERR "lockd_down: no lockd running.\n");
> + BUG();
> }
> + kthread_stop(nlmsvc_task);

I think all this user/foo checking here should be BUG_ONs as it's quite
fatal errors.

e.g.

void
lockd_down(void)
{
mutex_lock(&nlmsvc_mutex);

BUG_ON(!nlmsvc_task);
BUG_ON(!nlmsvc_users);

if (!--nlmsvc_users)
kthread_stop(nlmsvc_task);
mutex_unlock(&nlmsvc_mutex);
}


same applies for similar checks in lockd_up aswell.

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/