+ /* next */
+ n_from -= 1;
+ po += 1;
+ bi += 1;
+ next += 1;
+ }
+
+ /* packet trace if enabled */
+ if (PREDICT_FALSE ((n_trace = vlib_get_trace_count (vm, node))))
+ {
+ u32 n_left = n_rx_packets;
+ bi = to_next_bufs;
+ next = nexts;
+ u32 ni = next_index;
+ while (n_trace && n_left)
+ {
+ vlib_buffer_t *b;
+ memif_input_trace_t *tr;
+ if (mode != MEMIF_INTERFACE_MODE_ETHERNET)
+ ni = next[0];
+ b = vlib_get_buffer (vm, bi[0]);
+ vlib_trace_buffer (vm, node, ni, b, /* follow_chain */ 0);
+ tr = vlib_add_trace (vm, node, b, sizeof (*tr));
+ tr->next_index = ni;
+ tr->hw_if_index = mif->hw_if_index;
+ tr->ring = qid;
+
+ /* next */
+ n_trace--;
+ n_left--;
+ bi++;
+ next++;
+ }
+ vlib_set_trace_count (vm, node, n_trace);
+ }
+
+ if (mode == MEMIF_INTERFACE_MODE_ETHERNET)
+ {
+ n_left_to_next -= n_rx_packets;
+ vlib_put_next_frame (vm, node, next_index, n_left_to_next);
+ }
+ else
+ vlib_buffer_enqueue_to_next (vm, node, to_next_bufs, nexts, n_rx_packets);
+
+ vlib_increment_combined_counter (vnm->interface_main.combined_sw_if_counters
+ + VNET_INTERFACE_COUNTER_RX, thread_index,
+ mif->hw_if_index, n_rx_packets,
+ n_rx_bytes);
+
+ /* refill ring with empty buffers */
+refill:
+ vec_reset_length (ptd->buffers);
+ vec_reset_length (ptd->copy_ops);
+
+ if (type == MEMIF_RING_M2S)
+ {
+ u16 head = ring->head;
+ n_slots = ring_size - head + mq->last_tail;
+
+ while (n_slots--)
+ {
+ u16 s = head++ & mask;
+ memif_desc_t *d = &ring->desc[s];
+ d->length = mif->run.buffer_size;
+ }
+
+ CLIB_MEMORY_STORE_BARRIER ();
+ ring->head = head;
+ }
+
+ return n_rx_packets;
+}
+
+static_always_inline uword
+memif_device_input_zc_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
+ vlib_frame_t * frame, memif_if_t * mif,
+ u16 qid, memif_interface_mode_t mode)
+{
+ vnet_main_t *vnm = vnet_get_main ();
+ memif_main_t *mm = &memif_main;
+ memif_ring_t *ring;
+ memif_queue_t *mq;
+ u32 next_index;
+ uword n_trace = vlib_get_trace_count (vm, node);
+ u32 n_rx_packets = 0, n_rx_bytes = 0;
+ u32 *to_next = 0, *buffers;
+ u32 bi0, bi1, bi2, bi3;
+ u16 s0, s1, s2, s3;
+ memif_desc_t *d0, *d1, *d2, *d3;
+ vlib_buffer_t *b0, *b1, *b2, *b3;
+ u32 thread_index = vm->thread_index;
+ memif_per_thread_data_t *ptd = vec_elt_at_index (mm->per_thread_data,
+ thread_index);
+ u16 cur_slot, last_slot, ring_size, n_slots, mask, head;
+ i16 start_offset;
+ u32 buffer_length;
+ u16 n_alloc, n_from;
+
+ mq = vec_elt_at_index (mif->rx_queues, qid);
+ ring = mq->ring;
+ ring_size = 1 << mq->log2_ring_size;
+ mask = ring_size - 1;
+
+ next_index = (mode == MEMIF_INTERFACE_MODE_IP) ?
+ VNET_DEVICE_INPUT_NEXT_IP6_INPUT : VNET_DEVICE_INPUT_NEXT_ETHERNET_INPUT;
+
+ /* asume that somebody will want to add ethernet header on the packet
+ so start with IP header at offset 14 */
+ start_offset = (mode == MEMIF_INTERFACE_MODE_IP) ? 14 : 0;
+ buffer_length = VLIB_BUFFER_DEFAULT_FREE_LIST_BYTES - start_offset;
+
+ cur_slot = mq->last_tail;
+ last_slot = ring->tail;
+ if (cur_slot == last_slot)
+ goto refill;
+ n_slots = last_slot - cur_slot;