* Worse-case: must allow 2 supplementary entries for fct pointer.
*/
if (unlikely(head - tail >= DEFER_QUEUE_SIZE - 2)) {
assert(head - tail <= DEFER_QUEUE_SIZE);
rcu_defer_barrier_thread();
* Worse-case: must allow 2 supplementary entries for fct pointer.
*/
if (unlikely(head - tail >= DEFER_QUEUE_SIZE - 2)) {
assert(head - tail <= DEFER_QUEUE_SIZE);
rcu_defer_barrier_thread();