PIDNS_ADDING
if (unlikely(!(ns_of_pid(pid)->pid_allocated & PIDNS_ADDING))) {
case PIDNS_ADDING:
if (unlikely(!(ns->pid_allocated & PIDNS_ADDING)))
if (ns->pid_allocated == PIDNS_ADDING)
ns->pid_allocated &= ~PIDNS_ADDING;
.pid_allocated = PIDNS_ADDING,
BUILD_BUG_ON(PID_MAX_LIMIT >= PIDNS_ADDING);
ns->pid_allocated = PIDNS_ADDING;