PTP_MAX_TIMESTAMPS
WRITE_ONCE(queue->head, (queue->head + 1) % PTP_MAX_TIMESTAMPS);
return PTP_MAX_TIMESTAMPS - queue_cnt(q) - 1;
WRITE_ONCE(queue->head, (queue->head + 1) % PTP_MAX_TIMESTAMPS);
WRITE_ONCE(queue->tail, (queue->tail + 1) % PTP_MAX_TIMESTAMPS);
return cnt < 0 ? PTP_MAX_TIMESTAMPS + cnt : cnt;
struct ptp_extts_event buf[PTP_MAX_TIMESTAMPS];
WRITE_ONCE(queue->head, (queue->head + 1) % PTP_MAX_TIMESTAMPS);