Пример #1
0
static unsigned int 
kni_sock_poll(struct file *file, struct socket *sock, poll_table * wait)
{
	struct kni_vhost_queue *q = 
		container_of(sock->sk, struct kni_vhost_queue, sk);
	struct kni_dev *kni;
	unsigned int mask = 0;

	if (unlikely(q == NULL || q->kni == NULL))
		return POLLERR;

	kni = q->kni;
	KNI_DBG("start kni_poll on group %d, wq 0x%16llx\n", 
		  kni->group_id, (uint64_t)sock->wq);

	poll_wait(file, &sock->wq->wait, wait);

	if (kni_fifo_count(kni->rx_q) > 0)
		mask |= POLLIN | POLLRDNORM;

	if (sock_writeable(&q->sk) ||
	    (!test_and_set_bit(SOCK_ASYNC_NOSPACE, &q->sock->flags) &&
	     sock_writeable(&q->sk)))
		mask |= POLLOUT | POLLWRNORM;

	return mask;
}
Пример #2
0
/*
 * Checks if the user space application provided the resp message
 */
void
kni_net_poll_resp(struct kni_dev *kni)
{
	if (kni->kni_released) {
		return;
	}
	if (kni_fifo_count(kni->resp_q))
		wake_up_interruptible(&kni->wq);
}
Пример #3
0
/*
 * It can be called to process the request.
 */
static int
kni_net_process_request(struct kni_dev *kni, struct rte_kni_request *req)
{
	int ret = -1;
	void *resp_va;
	unsigned num;
	int ret_val;

	if (!kni || !req) {
		KNI_ERR("No kni instance or request\n");
		return -EINVAL;
	}

	mutex_lock(&kni->sync_lock);

	/* Construct data */
	memcpy(kni->sync_kva, req, sizeof(struct rte_kni_request));
	num = kni_fifo_put(kni->req_q, &kni->sync_va, 1);
	if (num < 1) {
		KNI_ERR("Cannot send to req_q\n");
		ret = -EBUSY;
		goto fail;
	}

	ret_val = wait_event_interruptible_timeout(kni->wq,
			kni_fifo_count(kni->resp_q), 3 * HZ);
	if (signal_pending(current) || ret_val <= 0) {
		ret = -ETIME;
		goto fail;
	}
	num = kni_fifo_get(kni->resp_q, (void **)&resp_va, 1);
	if (num != 1 || resp_va != kni->sync_va) {
		/* This should never happen */
		KNI_ERR("No data in resp_q\n");
		ret = -ENODATA;
		goto fail;
	}

	memcpy(req, kni->sync_kva, sizeof(struct rte_kni_request));
	ret = 0;

fail:
	mutex_unlock(&kni->sync_lock);
	return ret;
}
Пример #4
0
  /* Free skb and update statistics */
  dev_kfree_skb(skb);
  kni->stats.tx_dropped++;
  
  return NETDEV_TX_OK;
}

#else /*RTE_LIBRW_PIOT*/
static int
kni_net_tx(struct sk_buff *skb, struct net_device *dev)
{
	int len = 0;
	unsigned ret;
	struct kni_dev *kni = netdev_priv(dev);
	struct rte_kni_mbuf *pkt_kva = NULL;
	struct rte_kni_mbuf *pkt_va = NULL;

	dev->trans_start = jiffies; /* save the timestamp */

	/* Check if the length of skb is less than mbuf size */
	if (skb->len > kni->mbuf_size){
          goto drop;
        }

	/**
	 * Check if it has at least one free entry in tx_q and
	 * one entry in alloc_q.
	 */
	if (kni_fifo_free_count(kni->tx_q) == 0 ||
			kni_fifo_count(kni->alloc_q) == 0) {
		/**
		 * If no free entry in tx_q or no entry in alloc_q,
		 * drops skb and goes out.
		 */
		goto drop;
	}

	/* dequeue a mbuf from alloc_q */
	ret = kni_fifo_get(kni->alloc_q, (void **)&pkt_va, 1);
	if (likely(ret == 1)) {
		void *data_kva;

		pkt_kva = (void *)pkt_va - kni->mbuf_va + kni->mbuf_kva;
		data_kva = pkt_kva->buf_addr + pkt_kva->data_off - kni->mbuf_va
				+ kni->mbuf_kva;

		len = skb->len;
		memcpy(data_kva, skb->data, len);
		if (unlikely(len < ETH_ZLEN)) {
			memset(data_kva + len, 0, ETH_ZLEN - len);
			len = ETH_ZLEN;
		}
		pkt_kva->pkt_len = len;
		pkt_kva->data_len = len;
		/* enqueue mbuf into tx_q */
		ret = kni_fifo_put(kni->tx_q, (void **)&pkt_va, 1);
		if (unlikely(ret != 1)) {
			/* Failing should not happen */
			KNI_ERR("Fail to enqueue mbuf into tx_q\n");
			goto drop;
		}
	} else {
		/* Failing should not happen */
		KNI_ERR("Fail to dequeue mbuf from alloc_q\n");
		goto drop;
	}

	/* Free skb and update statistics */
	dev_kfree_skb(skb);
	kni->stats.tx_bytes += len;
	kni->stats.tx_packets++;

	return NETDEV_TX_OK;

drop:
	/* Free skb and update statistics */
	dev_kfree_skb(skb);
	kni->stats.tx_dropped++;

	return NETDEV_TX_OK;
}
Пример #5
0
static int
kni_net_tx(struct sk_buff *skb, struct net_device *dev)
{
  int len = 0;
  unsigned ret;
  struct kni_dev *kni = netdev_priv(dev);
  struct rte_kni_mbuf *pkt_kva;
  struct rte_kni_mbuf *pkt_va[RW_FPATH_KNI_MAX_SEGS];
  int num_req_mbuf = 1;

  int err;
  
  kni->tx_attempted++;

  err = skb_linearize(skb);
  if (unlikely(err)){
    goto drop;
  }
#ifdef RTE_LIBRW_NOHUGE
  if (kni->nohuge){
    kni->nl_tx_queued++;
    skb_queue_tail(&kni->skb_tx_queue,
                     skb);
    return NETDEV_TX_OK;    
  }

#endif
  dev->trans_start = jiffies; /* save the timestamp */
  
  /* Check if the length of skb is less than mbuf size */
  if (skb->len > kni->mbuf_size){
    num_req_mbuf = (skb->len/kni->mbuf_size) + 1;
    if (num_req_mbuf > RW_FPATH_KNI_MAX_SEGS){
      goto drop;
    }
  }
  

  if (kni->no_tx ||
      kni->no_data){
    goto drop;
  }
  if (kni_fifo_free_count(kni->tx_q) < num_req_mbuf){
    kni->tx_no_txq++;
    /**
     * If no free entry in tx_q or no entry in alloc_q,
     * drops skb and goes out.
     */
    goto drop;
  }
  if (kni_fifo_count(kni->alloc_q) < num_req_mbuf) {
    kni->tx_no_allocq++;
    /**
     * If no free entry in tx_q or no entry in alloc_q,
     * drops skb and goes out.
     */
    goto drop;
  }
  
  /* dequeue a mbuf from alloc_q */
  ret = kni_fifo_get(kni->alloc_q, (void **)&pkt_va[0], num_req_mbuf);
  
  if (likely(ret == num_req_mbuf)) {
    int seg_no = 0;
    int copylen, remlen;
    unsigned char *to, *from;
    int next;
    struct rte_kni_mbuf **prev;
    
    len = skb->len;

    prev = (struct rte_kni_mbuf **)&pkt_va[seg_no]->next;
    pkt_kva = (void *)pkt_va[seg_no] - kni->mbuf_va + kni->mbuf_kva;
    pkt_kva->pkt_len = len;
    RW_KNI_VF_SET_MDATA_PAYLOAD(&pkt_kva->meta_data,
                                skb->protocol);
    from = (unsigned char*)skb->data;
    
    to = (unsigned char*)(pkt_kva->buf_addr + pkt_kva->data_off - kni->mbuf_va
                          + kni->mbuf_kva);
    remlen = kni->mbuf_size;
    next = 0;
    
    while (len > 0) {
      copylen = len;
      if (copylen > remlen){
        next= 1;
        copylen = remlen;
      }
      
      memcpy(to, from, remlen);
      to += copylen;
      from += copylen;
      len -= copylen;
      remlen -= copylen;

      if (unlikely(len < ETH_ZLEN)) {
#if 0
        //AKKI
        memset(data_kva + len, 0, ETH_ZLEN - len);
        len = ETH_ZLEN;
#endif
      }
      pkt_kva->data_len += copylen;
      if (next){
        seg_no++;
        *prev = pkt_va[seg_no];
        prev = (struct rte_kni_mbuf **)&pkt_va[seg_no]->next;
        pkt_kva = (void *)pkt_va[seg_no] - kni->mbuf_va + kni->mbuf_kva;
        to = (unsigned char*)(pkt_kva->buf_addr + pkt_kva->data_off - kni->mbuf_va+ kni->mbuf_kva);
        remlen = kni->mbuf_size;
        next = 0;
        //AKKI increment the nb_segs.. bug bug
      }
    }
    
    /* enqueue mbuf into tx_q */
    ret = kni_fifo_put(kni->tx_q, (void **)&pkt_va[0], 1);
    if (unlikely(ret != 1)) {
      /* Failing should not happen */
      KNI_ERR("Fail to enqueue mbuf into tx_q\n");
      goto drop;
    }
  } else {
    /* Failing should not happen */
    KNI_ERR("Fail to dequeue mbuf from alloc_q\n");
    goto drop;
  }
  
  /* Free skb and update statistics */
  dev_kfree_skb(skb);
  kni->stats.tx_bytes += len;
  kni->stats.tx_packets++;
  
  return NETDEV_TX_OK;
  
drop:
  /* Free skb and update statistics */
  dev_kfree_skb(skb);
  kni->stats.tx_dropped++;
  
  return NETDEV_TX_OK;
}
Пример #6
0
/*
 * RX: loopback with enqueue/dequeue fifos and sk buffer copies.
 */
static void
kni_net_rx_lo_fifo_skb(struct kni_dev *kni)
{
	unsigned ret;
	uint32_t len;
	unsigned i, num_rq, num_fq, num;
	struct rte_kni_mbuf *kva;
	struct rte_kni_mbuf *va[MBUF_BURST_SZ];
	void * data_kva;

	struct sk_buff *skb;
	struct net_device *dev = kni->net_dev;

	/* Get the number of entries in rx_q */
	num_rq = kni_fifo_count(kni->rx_q);

	/* Get the number of free entries in free_q */
	num_fq = kni_fifo_free_count(kni->free_q);

	/* Calculate the number of entries to dequeue from rx_q */
	num = min(num_rq, num_fq);
	num = min(num, (unsigned)MBUF_BURST_SZ);

	/* Return if no entry to dequeue from rx_q */
	if (num == 0)
		return;

	/* Burst dequeue mbufs from rx_q */
	ret = kni_fifo_get(kni->rx_q, (void **)va, num);
	if (ret == 0)
		return;

	/* Copy mbufs to sk buffer and then call tx interface */
	for (i = 0; i < num; i++) {
		kva = (void *)va[i] - kni->mbuf_va + kni->mbuf_kva;
		len = kva->data_len;
		data_kva = kva->buf_addr + kva->data_off - kni->mbuf_va +
				kni->mbuf_kva;

		skb = dev_alloc_skb(len + 2);
		if (skb == NULL)
			KNI_ERR("Out of mem, dropping pkts\n");
		else {
                  /* Align IP on 16B boundary */
                  skb_reserve(skb, 2);
                  memcpy(skb_put(skb, len), data_kva, len);
                  skb->dev = dev;
                  skb->ip_summed = CHECKSUM_UNNECESSARY;
                  dev_kfree_skb(skb);
		}

		/* Simulate real usage, allocate/copy skb twice */
		skb = dev_alloc_skb(len + 2);
		if (skb == NULL) {
			KNI_ERR("Out of mem, dropping pkts\n");
			kni->stats.rx_dropped++;
		}
		else {
                  /* Align IP on 16B boundary */
			skb_reserve(skb, 2);
			memcpy(skb_put(skb, len), data_kva, len);
			skb->dev = dev;
			skb->ip_summed = CHECKSUM_UNNECESSARY;

			kni->stats.rx_bytes += len;
			kni->stats.rx_packets++;

			/* call tx interface */
			kni_net_tx(skb, dev);
		}
	}

	/* enqueue all the mbufs from rx_q into free_q */
	ret = kni_fifo_put(kni->free_q, (void **)&va, num);
	if (ret != num)
		/* Failing should not happen */
		KNI_ERR("Fail to enqueue mbufs into free_q\n");
}
Пример #7
0
/*
 * RX: loopback with enqueue/dequeue fifos.
 */
static void
kni_net_rx_lo_fifo(struct kni_dev *kni)
{
	unsigned ret;
	uint32_t len;
	unsigned i, num, num_rq, num_tq, num_aq, num_fq;
	struct rte_kni_mbuf *kva;
	struct rte_kni_mbuf *va[MBUF_BURST_SZ];
	void * data_kva;

	struct rte_kni_mbuf *alloc_kva;
	struct rte_kni_mbuf *alloc_va[MBUF_BURST_SZ];
	void *alloc_data_kva;

	/* Get the number of entries in rx_q */
	num_rq = kni_fifo_count(kni->rx_q);

	/* Get the number of free entrie in tx_q */
	num_tq = kni_fifo_free_count(kni->tx_q);

	/* Get the number of entries in alloc_q */
	num_aq = kni_fifo_count(kni->alloc_q);

	/* Get the number of free entries in free_q */
	num_fq = kni_fifo_free_count(kni->free_q);

	/* Calculate the number of entries to be dequeued from rx_q */
	num = min(num_rq, num_tq);
	num = min(num, num_aq);
	num = min(num, num_fq);
	num = min(num, (unsigned)MBUF_BURST_SZ);

	/* Return if no entry to dequeue from rx_q */
	if (num == 0)
		return;

	/* Burst dequeue from rx_q */
	ret = kni_fifo_get(kni->rx_q, (void **)va, num);
	if (ret == 0)
		return; /* Failing should not happen */

	/* Dequeue entries from alloc_q */
	ret = kni_fifo_get(kni->alloc_q, (void **)alloc_va, num);
	if (ret) {
		num = ret;
		/* Copy mbufs */
		for (i = 0; i < num; i++) {
			kva = (void *)va[i] - kni->mbuf_va + kni->mbuf_kva;
			len = kva->pkt_len;
			data_kva = kva->buf_addr + kva->data_off -
					kni->mbuf_va + kni->mbuf_kva;

			alloc_kva = (void *)alloc_va[i] - kni->mbuf_va +
							kni->mbuf_kva;
			alloc_data_kva = alloc_kva->buf_addr +
					alloc_kva->data_off - kni->mbuf_va +
							kni->mbuf_kva;
			memcpy(alloc_data_kva, data_kva, len);
			alloc_kva->pkt_len = len;
			alloc_kva->data_len = len;

			kni->stats.tx_bytes += len;
			kni->stats.rx_bytes += len;
		}

		/* Burst enqueue mbufs into tx_q */
		ret = kni_fifo_put(kni->tx_q, (void **)alloc_va, num);
		if (ret != num)
			/* Failing should not happen */
			KNI_ERR("Fail to enqueue mbufs into tx_q\n");
	}

	/* Burst enqueue mbufs into free_q */
	ret = kni_fifo_put(kni->free_q, (void **)va, num);
	if (ret != num)
		/* Failing should not happen */
		KNI_ERR("Fail to enqueue mbufs into free_q\n");

	/**
	 * Update statistic, and enqueue/dequeue failure is impossible,
	 * as all queues are checked at first.
	 */
	kni->stats.tx_packets += num;
	kni->stats.rx_packets += num;
}
Пример #8
0
/*
 * RX: normal working mode
 */
static void
kni_net_rx_normal(struct kni_dev *kni)
{
	unsigned ret;
	uint32_t len;
	unsigned i, num, num_rq, num_fq;
	struct rte_kni_mbuf *kva;
	struct rte_kni_mbuf *va[MBUF_BURST_SZ];
	void * data_kva;

	struct sk_buff *skb;
	struct net_device *dev = kni->net_dev;

	/* Get the number of entries in rx_q */
	num_rq = kni_fifo_count(kni->rx_q);

	/* Get the number of free entries in free_q */
	num_fq = kni_fifo_free_count(kni->free_q);

	/* Calculate the number of entries to dequeue in rx_q */
	num = min(num_rq, num_fq);
	num = min(num, (unsigned)MBUF_BURST_SZ);

	/* Return if no entry in rx_q and no free entry in free_q */
	if (num == 0)
		return;

	/* Burst dequeue from rx_q */
	ret = kni_fifo_get(kni->rx_q, (void **)va, num);
	if (ret == 0)
		return; /* Failing should not happen */

	/* Transfer received packets to netif */
	for (i = 0; i < num; i++) {
		kva = (void *)va[i] - kni->mbuf_va + kni->mbuf_kva;
                len = kva->data_len;
		data_kva = kva->buf_addr + kva->data_off - kni->mbuf_va
                    + kni->mbuf_kva;

		skb = dev_alloc_skb(len + 2);
		if (!skb) {
			KNI_ERR("Out of mem, dropping pkts\n");
			/* Update statistics */
			kni->stats.rx_dropped++;
		}
		else {
			/* Align IP on 16B boundary */
			skb_reserve(skb, 2);
			memcpy(skb_put(skb, len), data_kva, len);
			skb->dev = dev;

                        skb->protocol = eth_type_trans(skb, dev);
			skb->ip_summed = CHECKSUM_UNNECESSARY;
			/* Call netif interface */
			netif_rx(skb);

			/* Update statistics */
			kni->stats.rx_bytes += len;
			kni->stats.rx_packets++;
		}
	}

	/* Burst enqueue mbufs into free_q */
	ret = kni_fifo_put(kni->free_q, (void **)va, num);
	if (ret != num)
		/* Failing should not happen */
		KNI_ERR("Fail to enqueue entries into free_q\n");
}
Пример #9
0
/*
 * RX: normal working mode
 */
static void
kni_net_rx_normal(struct kni_dev *kni)
{
  unsigned ret;
  uint32_t pkt_len;
  uint32_t data_len;
  unsigned i, num, num_rq, num_fq;
  struct rte_kni_mbuf *kva;
  struct rte_kni_mbuf *va[MBUF_BURST_SZ];
  void * data_kva;
  int copied_len = 0;
  int num_segs = 0;
  
  struct sk_buff *skb;
  struct net_device *dev = kni->net_dev;
  
  if (kni->no_data){
    return;
  }
  
  /* Get the number of entries in rx_q */
  num_rq = kni_fifo_count(kni->rx_q);
  
  /* Get the number of free entries in free_q */
  num_fq = kni_fifo_free_count(kni->free_q);
  
  /* Calculate the number of entries to dequeue in rx_q */
  num = min(num_rq, num_fq);
  num = min(num, (unsigned)MBUF_BURST_SZ);
  
  /* Return if no entry in rx_q and no free entry in free_q */
  if (num == 0)
    return;
  
  /* Burst dequeue from rx_q */
  ret = kni_fifo_get(kni->rx_q, (void **)va, num);
  if (ret == 0)
    return; /* Failing should not happen */
  
  /* Transfer received packets to netif */
  for (i = 0; i < num; i++) {
    kva = (void *)va[i] - kni->mbuf_va + kni->mbuf_kva;
    pkt_len = kva->pkt_len;
    skb = dev_alloc_skb(pkt_len + 2);
    if (!skb) {
      KNI_ERR("Out of mem, dropping pkts\n");
      /* Update statistics */
      kni->stats.rx_dropped++;
      continue;
    }
    /* Align IP on 16B boundary */
    skb_reserve(skb, 2);
    copied_len = 0;
    num_segs = 0;
    kva = (void *)va[i];
    do {
      kva = (void *)kva  - kni->mbuf_va + kni->mbuf_kva;
      data_kva = kva->buf_addr + kva->data_off - kni->mbuf_va
          + kni->mbuf_kva;
      data_len = kva->data_len;
      memcpy(skb_put(skb, data_len), data_kva, data_len);
      copied_len += data_len;
      num_segs++;
    }while((kva = (void *)kva->next) != NULL);
    /*Go back to the head*/
    kva = (void *)va[i] - kni->mbuf_va + kni->mbuf_kva;

    kni_net_process_rx_packet(skb, dev, &kva->meta_data);
    kni->stats.rx_bytes += pkt_len;
  }
  /* Burst enqueue mbufs into free_q */
  ret = kni_fifo_put(kni->free_q, (void **)va, num);
  if (ret != num)
    /* Failing should not happen */
    KNI_ERR("Fail to enqueue entries into free_q\n");
}
Пример #10
0
static inline int
kni_vhost_net_tx(struct kni_dev *kni, struct msghdr *m,
		 unsigned offset, unsigned len)
{
	struct rte_kni_mbuf *pkt_kva = NULL;
	struct rte_kni_mbuf *pkt_va = NULL;
	int ret;

	KNI_DBG_TX("tx offset=%d, len=%d, iovlen=%d\n",
#ifdef HAVE_IOV_ITER_MSGHDR
		   offset, len, (int)m->msg_iter.iov->iov_len);
#else
		   offset, len, (int)m->msg_iov->iov_len);
#endif

	/**
	 * Check if it has at least one free entry in tx_q and
	 * one entry in alloc_q.
	 */
	if (kni_fifo_free_count(kni->tx_q) == 0 ||
	    kni_fifo_count(kni->alloc_q) == 0) {
		/**
		 * If no free entry in tx_q or no entry in alloc_q,
		 * drops skb and goes out.
		 */
		goto drop;
	}

	/* dequeue a mbuf from alloc_q */
	ret = kni_fifo_get(kni->alloc_q, (void **)&pkt_va, 1);
	if (likely(ret == 1)) {
		void *data_kva;

		pkt_kva = (void *)pkt_va - kni->mbuf_va + kni->mbuf_kva;
		data_kva = pkt_kva->buf_addr + pkt_kva->data_off
		           - kni->mbuf_va + kni->mbuf_kva;

#ifdef HAVE_IOV_ITER_MSGHDR
		copy_from_iter(data_kva, len, &m->msg_iter);
#else
		memcpy_fromiovecend(data_kva, m->msg_iov, offset, len);
#endif

		if (unlikely(len < ETH_ZLEN)) {
			memset(data_kva + len, 0, ETH_ZLEN - len);
			len = ETH_ZLEN;
		}
		pkt_kva->pkt_len = len;
		pkt_kva->data_len = len;

		/* enqueue mbuf into tx_q */
		ret = kni_fifo_put(kni->tx_q, (void **)&pkt_va, 1);
		if (unlikely(ret != 1)) {
			/* Failing should not happen */
			KNI_ERR("Fail to enqueue mbuf into tx_q\n");
			goto drop;
		}
	} else {
		/* Failing should not happen */
		KNI_ERR("Fail to dequeue mbuf from alloc_q\n");
		goto drop;
	}

	/* update statistics */
	kni->stats.tx_bytes += len;
	kni->stats.tx_packets++;

	return 0;

drop:
	/* update statistics */
	kni->stats.tx_dropped++;

	return 0;
}
Пример #11
0
int
kni_chk_vhost_rx(struct kni_dev *kni)
{
	struct kni_vhost_queue *q = kni->vhost_queue;
	unsigned nb_in, nb_mbuf, nb_skb;
	const unsigned BURST_MASK = RX_BURST_SZ - 1;
	unsigned nb_burst, nb_backlog, i;
	struct sk_buff *skb[RX_BURST_SZ];
	struct rte_kni_mbuf *va[RX_BURST_SZ];

	if (unlikely(BE_STOP & kni->vq_status)) {
		kni->vq_status |= BE_FINISH;
		return 0;
	}

	if (unlikely(q == NULL))
		return 0;

	nb_skb = kni_fifo_count(q->fifo);
	nb_mbuf = kni_fifo_count(kni->rx_q);

	nb_in = min(nb_mbuf, nb_skb);
	nb_in = min(nb_in, (unsigned)RX_BURST_SZ);
	nb_burst   = (nb_in & ~BURST_MASK);
	nb_backlog = (nb_in & BURST_MASK);

	/* enqueue skb_queue per BURST_SIZE bulk */
	if (0 != nb_burst) {
		if (unlikely(RX_BURST_SZ != kni_fifo_get(
				     kni->rx_q, (void **)&va,
				     RX_BURST_SZ)))
			goto except;

		if (unlikely(RX_BURST_SZ != kni_fifo_get(
				     q->fifo, (void **)&skb,
				     RX_BURST_SZ)))
			goto except;

		kni_vhost_enqueue_burst(kni, q, skb, va);
	}

	/* all leftover, do one by one */
	for (i = 0; i < nb_backlog; ++i) {
		if (unlikely(1 != kni_fifo_get(
				     kni->rx_q,(void **)&va, 1)))
			goto except;

		if (unlikely(1 != kni_fifo_get(
				     q->fifo, (void **)&skb, 1)))
			goto except;

		kni_vhost_enqueue(kni, q, *skb, *va);
	}

	/* Ondemand wake up */
	if ((nb_in == RX_BURST_SZ) || (nb_skb == 0) ||
	    ((nb_mbuf < RX_BURST_SZ) && (nb_mbuf != 0))) {
		wake_up_interruptible_poll(sk_sleep(&q->sk),
				   POLLIN | POLLRDNORM | POLLRDBAND);
		KNI_DBG_RX("RX CHK KICK nb_mbuf %d, nb_skb %d, nb_in %d\n",
			   nb_mbuf, nb_skb, nb_in);
	}

	return 0;

except:
	/* Failing should not happen */
	KNI_ERR("Fail to enqueue fifo, it shouldn't happen \n");
	BUG_ON(1);

	return 0;
}