On Thu, May 15, 2025 at 11:23 AM Pasha Tatashin
<pasha.tatashin@xxxxxxxxxx> wrote:
>
> +int liveupdate_register_subsystem(struct liveupdate_subsystem *h)
> +{
> + struct liveupdate_subsystem *iter;
> + int ret = 0;
> +
> + luo_state_read_enter();
> + if (!liveupdate_state_normal() && !liveupdate_state_updated()) {
> + luo_state_read_exit();
> + return -EBUSY;
> + }
> +
> + mutex_lock(&luo_subsystem_list_mutex);
> + list_for_each_entry(iter, &luo_subsystems_list, list) {
> + if (iter == h) {
> + pr_warn("Subsystem '%s' (%p) already registered.\n",
> + h->name, h);
> + ret = -EEXIST;
> + goto out_unlock;
> + }
> +
> + if (!strcmp(iter->name, h->name)) {
> + pr_err("Subsystem with name '%s' already registered.\n",
> + h->name);
> + ret = -EEXIST;
> + goto out_unlock;
> + }
> + }
> +
> + INIT_LIST_HEAD(&h->list);
> + list_add_tail(&h->list, &luo_subsystems_list);
> +
> +out_unlock:
> + mutex_unlock(&luo_subsystem_list_mutex);
> + luo_state_read_exit();
> +
> + return ret;
> +}
Suggest using guard()() and scoped_guard() throughout this series
instead of manual lock/unlock and up/down. That will simplify the code
and reduce the chance of silly bugs where a code path misses an
unlock/down.
