Function vhost_need_event

dpdk/lib/vhost/vhost.h:906–910

* The following is used with VIRTIO_RING_F_EVENT_IDX. * Assuming a given event_idx value from the other size, if we have * just incremented index from old to new_idx, should we trigger an * event? */

 * event?
 */
static __rte_always_inline int
vhost_need_event(uint16_t event_idx, uint16_t new_idx, uint16_t old)
{
	return (uint16_t)(new_idx - event_idx - 1) < (uint16_t)(new_idx - old);
}

static __rte_always_inline void
vhost_vring_inject_irq(struct virtio_net *dev, struct vhost_virtqueue *vq)