u32 head; /**< fifo head position/byte */
volatile u32 want_deq_ntf; /**< producer wants nudge */
volatile u32 has_deq_ntf;
+ u32 deq_thresh; /**< fifo threshold used for notifications */
CLIB_CACHE_LINE_ALIGN_MARK (producer);
u32 tail; /**< fifo tail position/byte */