Questions about the number of members of the "struct list_head notify" queue in rpcsvc_t

[jifengzhou]

In the rpc svc handledisconnect function of rpcsvc.c, there is a code to traverse the "svc->notify" member, but I observe that some service processes of glusterfs only register a notify member when registering. What is the purpose of traversal in the code? Under what circumstances will svc have multiple notify members? thanks！

rpcsvc_handle_disconnect(rpcsvc_t *svc, rpc_transport_t *trans)
{
rpcsvc_event_t event;
rpcsvc_notify_wrapper_t *wrappers = NULL, *wrapper;
.....
list_for_each_entry(wrapper, &svc->notify, list)
{
if (wrapper->notify) {
wrappers[i++] = *wrapper;
}
}
.....
}