[dpdk-dev,5/7] net/virtio: support IN_ORDER Rx and Tx
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Commit Message
IN_ORDER Rx function can support merge-able feature. Descriptors
allocation and free will be done in bulk.
Virtio dequeue logic:
dequeue_burst_rx(burst mbufs)
for (each mbuf b) {
if (b need merge) {
merge remained mbufs
add merged mbuf to return mbufs list
} else {
add mbuf to return mbufs list
}
}
if (last mbuf c need merge) {
dequeue_burst_rx(required mbufs)
merge last mbuf c
}
refill_avail_ring_bulk()
update_avail_ring()
return mbufs list
IN_ORDER Tx function can support indirect and offloading features.
Virtio enqueue logic:
xmit_cleanup(used descs)
for (each xmit mbuf b) {
if (b can inorder xmit) {
add mbuf b to inorder burst list
} else {
xmit inorder burst list
xmit mbuf b with normal xmit
}
}
if (inorder burst list not empty) {
xmit inorder burst list
}
update_avail_ring()
Signed-off-by: Marvin Liu <yong.liu@intel.com>
Comments
On Fri, Jun 08, 2018 at 05:07:22PM +0800, Marvin Liu wrote:
> IN_ORDER Rx function can support merge-able feature. Descriptors
> allocation and free will be done in bulk.
>
> Virtio dequeue logic:
> dequeue_burst_rx(burst mbufs)
> for (each mbuf b) {
> if (b need merge) {
> merge remained mbufs
> add merged mbuf to return mbufs list
> } else {
> add mbuf to return mbufs list
> }
> }
> if (last mbuf c need merge) {
> dequeue_burst_rx(required mbufs)
> merge last mbuf c
> }
> refill_avail_ring_bulk()
> update_avail_ring()
> return mbufs list
>
> IN_ORDER Tx function can support indirect and offloading features.
>
> Virtio enqueue logic:
> xmit_cleanup(used descs)
> for (each xmit mbuf b) {
> if (b can inorder xmit) {
> add mbuf b to inorder burst list
> } else {
> xmit inorder burst list
> xmit mbuf b with normal xmit
> }
> }
> if (inorder burst list not empty) {
> xmit inorder burst list
> }
> update_avail_ring()
>
> Signed-off-by: Marvin Liu <yong.liu@intel.com>
>
> diff --git a/drivers/net/virtio/virtio_ethdev.h b/drivers/net/virtio/virtio_ethdev.h
> index bb40064ea..25697c872 100644
> --- a/drivers/net/virtio/virtio_ethdev.h
> +++ b/drivers/net/virtio/virtio_ethdev.h
> @@ -83,9 +83,15 @@ uint16_t virtio_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts,
> uint16_t virtio_recv_mergeable_pkts(void *rx_queue, struct rte_mbuf **rx_pkts,
> uint16_t nb_pkts);
>
> +uint16_t virtio_recv_inorder_pkts(void *rx_queue, struct rte_mbuf **rx_pkts,
> + uint16_t nb_pkts);
> +
> uint16_t virtio_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
> uint16_t nb_pkts);
>
> +uint16_t virtio_xmit_inorder_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
> + uint16_t nb_pkts);
> +
> uint16_t virtio_recv_pkts_vec(void *rx_queue, struct rte_mbuf **rx_pkts,
> uint16_t nb_pkts);
>
> diff --git a/drivers/net/virtio/virtio_rxtx.c b/drivers/net/virtio/virtio_rxtx.c
> index 0bca29855..d0473d6b4 100644
> --- a/drivers/net/virtio/virtio_rxtx.c
> +++ b/drivers/net/virtio/virtio_rxtx.c
> @@ -122,6 +122,45 @@ virtqueue_dequeue_burst_rx(struct virtqueue *vq, struct rte_mbuf **rx_pkts,
> return i;
> }
>
> +static uint16_t
> +virtqueue_dequeue_inorder_rx(struct virtqueue *vq,
virtqueue_dequeue_burst_rx_inorder() will be better.
> + struct rte_mbuf **rx_pkts,
> + uint32_t *len,
> + uint16_t num)
> +{
> + struct vring_used_elem *uep;
> + struct rte_mbuf *cookie;
> + uint16_t used_idx;
> + uint16_t i;
> +
> + if (unlikely(num == 0))
> + return 0;
> +
> + used_idx = vq->vq_used_cons_idx & (vq->vq_nentries - 1);
Above assignment is misleading.
> + for (i = 0; i < num; i++) {
> + used_idx = vq->vq_used_cons_idx & (vq->vq_nentries - 1);
> + /* Desc idx same as used idx */
> + uep = &vq->vq_ring.used->ring[used_idx];
> + len[i] = uep->len;
> + cookie = (struct rte_mbuf *)vq->vq_descx[used_idx].cookie;
> +
> + if (unlikely(cookie == NULL)) {
> + PMD_DRV_LOG(ERR, "vring descriptor with no mbuf cookie at %u",
> + vq->vq_used_cons_idx);
> + break;
> + }
> +
> + rte_prefetch0(cookie);
> + rte_packet_prefetch(rte_pktmbuf_mtod(cookie, void *));
> + rx_pkts[i] = cookie;
> + vq->vq_used_cons_idx++;
> + vq->vq_descx[used_idx].cookie = NULL;
> + }
> +
> + vq_ring_free_inorder(vq, used_idx, i);
> + return i;
> +}
> +
> #ifndef DEFAULT_TX_FREE_THRESH
> #define DEFAULT_TX_FREE_THRESH 32
> #endif
> @@ -150,6 +189,70 @@ virtio_xmit_cleanup(struct virtqueue *vq, uint16_t num)
> }
> }
>
> +/* Cleanup from completed inorder transmits. */
> +static void
> +virtio_xmit_cleanup_inorder(struct virtqueue *vq, uint16_t num)
> +{
> + uint16_t i, used_idx;
> +
> + used_idx = vq->vq_used_cons_idx & (vq->vq_nentries - 1);
Above assignment is misleading.
> + for (i = 0; i < num; i++) {
> + struct vq_desc_extra *dxp;
> +
> + used_idx = vq->vq_used_cons_idx & (vq->vq_nentries - 1);
> + dxp = &vq->vq_descx[used_idx];
> + vq->vq_used_cons_idx++;
> +
> + if (dxp->cookie != NULL) {
> + rte_pktmbuf_free(dxp->cookie);
> + dxp->cookie = NULL;
> + }
> + }
> + vq_ring_free_inorder(vq, used_idx, num);
If num is zero, we can't free used_idx.
> +}
> +
> +static inline int
> +virtqueue_enqueue_inorder_refill(struct virtqueue *vq,
virtqueue_enqueue_recv_refill_inorder() will be better.
> + struct rte_mbuf **cookies,
> + uint16_t num)
> +{
> + struct vq_desc_extra *dxp;
> + struct virtio_hw *hw = vq->hw;
> + struct vring_desc *start_dp;
> + uint16_t head_idx, idx, i = 0;
> +
> + if (unlikely(vq->vq_free_cnt == 0))
> + return -ENOSPC;
> + if (unlikely(vq->vq_free_cnt < num))
> + return -EMSGSIZE;
> +
> + head_idx = vq->vq_desc_head_idx & (vq->vq_nentries - 1);
> + start_dp = vq->vq_ring.desc;
> +
> + while (i < num) {
> + idx = head_idx & (vq->vq_nentries - 1);
> + dxp = &vq->vq_descx[idx];
> + dxp->cookie = (void *)(struct rte_mbuf *)cookies[i];
Casting isn't necessary.
> + dxp->ndescs = 1;
> +
> + start_dp[idx].addr =
> + VIRTIO_MBUF_ADDR(cookies[i], vq) +
> + RTE_PKTMBUF_HEADROOM - hw->vtnet_hdr_size;
> + start_dp[idx].len =
> + cookies[i]->buf_len -
> + RTE_PKTMBUF_HEADROOM +
> + hw->vtnet_hdr_size;
> + start_dp[idx].flags = VRING_DESC_F_WRITE;
> +
> + head_idx++;
> + i++;
> + }
> +
> + vq->vq_avail_idx += num;
> + vq->vq_desc_head_idx += num;
> + vq->vq_free_cnt = (uint16_t)(vq->vq_free_cnt - num);
> + return 0;
> +}
>
> static inline int
> virtqueue_enqueue_recv_refill(struct virtqueue *vq, struct rte_mbuf *cookie)
> @@ -246,9 +349,113 @@ tx_offload_enabled(struct virtio_hw *hw)
> (var) = (val); \
> } while (0)
>
[...]
> +
> +static void
> +virtio_discard_inorder_rxbuf(struct virtqueue *vq, struct rte_mbuf *m)
virtio_discard_rxbuf_inorder() will be better.
> +{
> + int error;
> +
> + error = virtqueue_enqueue_inorder_refill(vq, &m, 1);
> if (unlikely(error)) {
> RTE_LOG(ERR, PMD, "cannot requeue discarded mbuf");
> rte_pktmbuf_free(m);
> @@ -813,6 +1002,191 @@ virtio_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts, uint16_t nb_pkts)
> return nb_rx;
> }
>
> +uint16_t
> +virtio_recv_inorder_pkts(void *rx_queue,
virtio_recv_mergeable_pkts_inorder() will be better.
> + struct rte_mbuf **rx_pkts,
> + uint16_t nb_pkts)
> +{
> + struct virtnet_rx *rxvq = rx_queue;
> + struct virtqueue *vq = rxvq->vq;
> + struct virtio_hw *hw = vq->hw;
> + struct rte_mbuf *rxm;
> + struct rte_mbuf *prev;
> + uint16_t nb_used, num, nb_rx;
> + uint32_t len[VIRTIO_MBUF_BURST_SZ];
> + struct rte_mbuf *rcv_pkts[VIRTIO_MBUF_BURST_SZ];
> + int error;
> + uint32_t i, nb_enqueued;
> + uint32_t seg_num;
> + uint32_t seg_res;
> + uint32_t hdr_size;
> + int offload;
> +
> + nb_rx = 0;
> + if (unlikely(hw->started == 0))
> + return nb_rx;
> +
> + nb_used = VIRTQUEUE_NUSED(vq);
> + nb_used = RTE_MIN(nb_used, nb_pkts);
> + nb_used = RTE_MIN(nb_used, VIRTIO_MBUF_BURST_SZ);
> +
> + virtio_rmb();
> +
> + PMD_RX_LOG(DEBUG, "used:%d", nb_used);
> +
> + i = 0;
> + nb_enqueued = 0;
> + seg_num = 1;
> + seg_res = 0;
> + hdr_size = hw->vtnet_hdr_size;
> + offload = rx_offload_enabled(hw);
> +
> + num = virtqueue_dequeue_inorder_rx(vq, rcv_pkts, len, nb_used);
> +
> + for (; i < num; i++) {
Why not initialize i in for ()?
> + struct virtio_net_hdr_mrg_rxbuf *header;
> +
> + PMD_RX_LOG(DEBUG, "dequeue:%d", num);
> + PMD_RX_LOG(DEBUG, "packet len:%d", len[i]);
> +
> + rxm = rcv_pkts[i];
> +
> + if (unlikely(len[i] < hdr_size + ETHER_HDR_LEN)) {
> + PMD_RX_LOG(ERR, "Packet drop");
> + nb_enqueued++;
> + virtio_discard_inorder_rxbuf(vq, rxm);
> + rxvq->stats.errors++;
> + continue;
> + }
> +
> + header = (struct virtio_net_hdr_mrg_rxbuf *)((char *)rxm->buf_addr +
> + RTE_PKTMBUF_HEADROOM - hdr_size);
> + seg_num = header->num_buffers;
> +
> + if (seg_num == 0)
> + seg_num = 1;
> +
> + rxm->data_off = RTE_PKTMBUF_HEADROOM;
> + rxm->nb_segs = seg_num;
> + rxm->ol_flags = 0;
> + rxm->vlan_tci = 0;
> + rxm->pkt_len = (uint32_t)(len[i] - hdr_size);
> + rxm->data_len = (uint16_t)(len[i] - hdr_size);
> +
> + rxm->port = rxvq->port_id;
> +
> + rx_pkts[nb_rx] = rxm;
> + prev = rxm;
> +
> + if (offload && virtio_rx_offload(rxm, &header->hdr) < 0) {
> + virtio_discard_inorder_rxbuf(vq, rxm);
> + rxvq->stats.errors++;
> + continue;
> + }
> +
> + seg_res = seg_num - 1;
> +
> + /* Merge remaining segments */
> + while (seg_res != 0 && i < num) {
> + rxm = rcv_pkts[i];
> + rxm->data_off = RTE_PKTMBUF_HEADROOM - hdr_size;
> + rxm->pkt_len = (uint32_t)(len[i]);
> + rxm->data_len = (uint16_t)(len[i]);
> +
> + rx_pkts[nb_rx]->pkt_len += (uint32_t)(len[i]);
> + rx_pkts[nb_rx]->data_len += (uint16_t)(len[i]);
> +
> + i++;
> +
> + if (prev)
> + prev->next = rxm;
> +
> + prev = rxm;
> + seg_res -= 1;
> + }
> +
> + if (hw->vlan_strip)
> + rte_vlan_strip(rx_pkts[nb_rx]);
> +
> + VIRTIO_DUMP_PACKET(rx_pkts[nb_rx],
> + rx_pkts[nb_rx]->data_len);
> +
> + rxvq->stats.bytes += rx_pkts[nb_rx]->pkt_len;
> + virtio_update_packet_stats(&rxvq->stats, rx_pkts[nb_rx]);
When seg_res != 0, we cannot run above code.
> + nb_rx++;
> + }
> +
> + /* Last packet still need merge segments */
> + while (seg_res != 0) {
> + uint16_t rcv_cnt = RTE_MIN((uint16_t)seg_res,
> + VIRTIO_MBUF_BURST_SZ);
> +
> + prev = rcv_pkts[nb_rx - 1];
> + if (likely(VIRTQUEUE_NUSED(vq) >= rcv_cnt)) {
> + num = virtqueue_dequeue_inorder_rx(vq, rcv_pkts, len,
> + rcv_cnt);
> + uint16_t extra_idx = 0;
> +
> + rcv_cnt = num;
> + while (extra_idx < rcv_cnt) {
> + rxm = rcv_pkts[extra_idx];
> + rxm->data_off = RTE_PKTMBUF_HEADROOM - hdr_size;
> + rxm->pkt_len = (uint32_t)(len[extra_idx]);
> + rxm->data_len = (uint16_t)(len[extra_idx]);
> + prev->next = rxm;
> + prev = rxm;
> + rx_pkts[nb_rx - 1]->pkt_len += len[extra_idx];
> + rx_pkts[nb_rx - 1]->data_len += len[extra_idx];
> + extra_idx += 1;
> + };
> + seg_res -= rcv_cnt;
> + } else {
> + PMD_RX_LOG(ERR,
> + "No enough segments for packet.");
> + virtio_discard_inorder_rxbuf(vq, prev);
> + rxvq->stats.errors++;
> + nb_rx--;
> + break;
> + }
> + }
> +
> + rxvq->stats.packets += nb_rx;
> +
> + /* Allocate new mbuf for the used descriptor */
> + error = ENOSPC;
Above assignment is meaningless.
> +
> + if (likely(!virtqueue_full(vq))) {
> + /* free_cnt may include mrg descs */
> + uint16_t free_cnt = vq->vq_free_cnt;
> + struct rte_mbuf *new_pkts[free_cnt];
> +
> + if (!rte_pktmbuf_alloc_bulk(rxvq->mpool, new_pkts, free_cnt)) {
> + error = virtqueue_enqueue_inorder_refill(vq, new_pkts,
> + free_cnt);
> + if (unlikely(error)) {
> + for (i = 0; i < free_cnt; i++)
> + rte_pktmbuf_free(new_pkts[i]);
> + }
> + nb_enqueued += free_cnt;
> + } else {
> + struct rte_eth_dev *dev
> + = &rte_eth_devices[rxvq->port_id];
> + dev->data->rx_mbuf_alloc_failed += free_cnt;
> + }
> + }
> +
> + if (likely(nb_enqueued)) {
> + vq_update_avail_idx(vq);
> +
> + if (unlikely(virtqueue_kick_prepare(vq))) {
> + virtqueue_notify(vq);
> + PMD_RX_LOG(DEBUG, "Notified");
> + }
> + }
> +
> + return nb_rx;
> +}
> +
> uint16_t
> virtio_recv_mergeable_pkts(void *rx_queue,
> struct rte_mbuf **rx_pkts,
> @@ -1060,7 +1434,8 @@ virtio_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts, uint16_t nb_pkts)
> }
>
> /* Enqueue Packet buffers */
> - virtqueue_enqueue_xmit(txvq, txm, slots, use_indirect, can_push);
> + virtqueue_enqueue_xmit(txvq, txm, slots, use_indirect,
> + can_push, 0);
>
> txvq->stats.bytes += txm->pkt_len;
> virtio_update_packet_stats(&txvq->stats, txm);
> @@ -1079,3 +1454,121 @@ virtio_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts, uint16_t nb_pkts)
>
> return nb_tx;
> }
> +
> +uint16_t
> +virtio_xmit_inorder_pkts(void *tx_queue,
virtio_xmit_pkts_inorder() will be better.
> + struct rte_mbuf **tx_pkts,
> + uint16_t nb_pkts)
> +{
> + struct virtnet_tx *txvq = tx_queue;
> + struct virtqueue *vq = txvq->vq;
> + struct virtio_hw *hw = vq->hw;
> + uint16_t hdr_size = hw->vtnet_hdr_size;
> + uint16_t nb_used, nb_avail, nb_tx = 0, inorder_tx = 0;
> + struct rte_mbuf *inorder_pkts[nb_pkts];
> + int error;
> +
> + if (unlikely(hw->started == 0 && tx_pkts != hw->inject_pkts))
> + return nb_tx;
> +
> + if (unlikely(nb_pkts < 1))
> + return nb_pkts;
> +
> + VIRTQUEUE_DUMP(vq);
> + PMD_TX_LOG(DEBUG, "%d packets to xmit", nb_pkts);
> + nb_used = VIRTQUEUE_NUSED(vq);
> +
> + virtio_rmb();
> + if (likely(nb_used > vq->vq_nentries - vq->vq_free_thresh))
> + virtio_xmit_cleanup_inorder(vq, nb_used);
> +
> + nb_avail = RTE_MIN(vq->vq_free_cnt, nb_pkts);
> +
> + for (nb_tx = 0; nb_tx < nb_avail; nb_tx++) {
> + struct rte_mbuf *txm = tx_pkts[nb_tx];
> + int slots, need;
> + int can_push = 0, use_indirect = 0, flush_inorder = 1;
> +
> + /* Do VLAN tag insertion */
> + if (unlikely(txm->ol_flags & PKT_TX_VLAN_PKT)) {
> + error = rte_vlan_insert(&txm);
> + if (unlikely(error)) {
> + rte_pktmbuf_free(txm);
> + continue;
> + }
> + }
> +
> + txvq->stats.bytes += txm->pkt_len;
> + virtio_update_packet_stats(&txvq->stats, txm);
> +
> + /* optimize ring usage */
> + if ((vtpci_with_feature(hw, VIRTIO_F_ANY_LAYOUT) ||
> + vtpci_with_feature(hw, VIRTIO_F_VERSION_1)) &&
> + rte_mbuf_refcnt_read(txm) == 1 &&
> + RTE_MBUF_DIRECT(txm) &&
> + txm->nb_segs == 1 &&
> + rte_pktmbuf_headroom(txm) >= hdr_size &&
> + rte_is_aligned(rte_pktmbuf_mtod(txm, char *),
> + __alignof__(struct virtio_net_hdr_mrg_rxbuf))) {
> + can_push = 1;
There is no need to have 'can_push' any more.
> +
> + inorder_pkts[inorder_tx] = txm;
> + inorder_tx++;
inorder_tx isn't a good name.
> + flush_inorder = 0;
I think there is no need to introduce 'flush_inorder'.
And it will make the code much more readable by writing
the code like:
for (nb_tx = 0; nb_tx < nb_avail; nb_tx++) {
struct rte_mbuf *txm = tx_pkts[nb_tx];
......
if ((vtpci_with_feature(hw, VIRTIO_F_ANY_LAYOUT) ||
vtpci_with_feature(hw, VIRTIO_F_VERSION_1)) &&
rte_mbuf_refcnt_read(txm) == 1 &&
RTE_MBUF_DIRECT(txm) &&
txm->nb_segs == 1 &&
rte_pktmbuf_headroom(txm) >= hdr_size &&
rte_is_aligned(rte_pktmbuf_mtod(txm, char *),
__alignof__(struct virtio_net_hdr_mrg_rxbuf))) {
inorder_pkts[nb_inorder_pkts++] = txm;
continue;
}
/* Flush inorder packets if any. */
if (nb_inorder_pkts) {
virtqueue_enqueue_xmit_inorder(txvq, inorder_pkts,
nb_inorder_pkts);
nb_inorder_pkts = 0;
}
......
virtqueue_enqueue_xmit(txvq, txm, slots, 0, 0, 1);
}
/* Flush inorder packets if any. */
if (nb_inorder_pkts) {
virtqueue_enqueue_xmit_inorder(txvq, inorder_pkts,
nb_inorder_pkts);
nb_inorder_pkts = 0;
}
> + } else if (vtpci_with_feature(hw, VIRTIO_RING_F_INDIRECT_DESC) &&
> + txm->nb_segs < VIRTIO_MAX_TX_INDIRECT) {
> + use_indirect = 1;
> + }
There is no need to try to use INDIRECT.
> +
> + if (flush_inorder) {
> + /* Flush inorder packets */
> + virtqueue_enqueue_xmit_inorder(txvq, inorder_pkts,
> + inorder_tx);
> + inorder_tx = 0;
> +
> + /* How many main ring entries are needed to this Tx?
> + * any_layout => number of segments
> + * indirect => 1
> + * default => number of segments + 1
> + */
> + slots = use_indirect ? 1 : (txm->nb_segs + !can_push);
> + need = slots - vq->vq_free_cnt;
> +
> + if (unlikely(need > 0)) {
> + nb_used = VIRTQUEUE_NUSED(vq);
> + virtio_rmb();
> + need = RTE_MIN(need, (int)nb_used);
> +
> + virtio_xmit_cleanup_inorder(vq, need);
> + need = slots - vq->vq_free_cnt;
> + if (unlikely(need > 0)) {
> + PMD_TX_LOG(ERR,
> + "No free tx descriptors to transmit");
> + break;
> + }
> + }
> + /* Enqueue Packet buffers */
> + virtqueue_enqueue_xmit(txvq, txm, slots, use_indirect,
> + can_push, 1);
> + }
> + }
> +
> + /* Transmit all inorder packets */
> + if (inorder_tx)
> + virtqueue_enqueue_xmit_inorder(txvq, inorder_pkts, inorder_tx);
> +
> + txvq->stats.packets += nb_tx;
> +
> + if (likely(nb_tx)) {
> + vq_update_avail_idx(vq);
> +
> + if (unlikely(virtqueue_kick_prepare(vq))) {
> + virtqueue_notify(vq);
> + PMD_TX_LOG(DEBUG, "Notified backend after xmit");
> + }
> + }
> +
> + VIRTQUEUE_DUMP(vq);
> +
> + return nb_tx;
> +}
> --
> 2.17.0
>
> -----Original Message-----
> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Tiwei Bie
> Sent: Wednesday, June 20, 2018 3:41 PM
> To: Liu, Yong <yong.liu@intel.com>
> Cc: maxime.coquelin@redhat.com; Wang, Zhihong <zhihong.wang@intel.com>;
> dev@dpdk.org
> Subject: Re: [dpdk-dev] [PATCH 5/7] net/virtio: support IN_ORDER Rx and Tx
>
> On Fri, Jun 08, 2018 at 05:07:22PM +0800, Marvin Liu wrote:
> > IN_ORDER Rx function can support merge-able feature. Descriptors
> > allocation and free will be done in bulk.
> >
> > Virtio dequeue logic:
> > dequeue_burst_rx(burst mbufs)
> > for (each mbuf b) {
> > if (b need merge) {
> > merge remained mbufs
> > add merged mbuf to return mbufs list
> > } else {
> > add mbuf to return mbufs list
> > }
> > }
> > if (last mbuf c need merge) {
> > dequeue_burst_rx(required mbufs)
> > merge last mbuf c
> > }
> > refill_avail_ring_bulk()
> > update_avail_ring()
> > return mbufs list
> >
> > IN_ORDER Tx function can support indirect and offloading features.
> >
> > Virtio enqueue logic:
> > xmit_cleanup(used descs)
> > for (each xmit mbuf b) {
> > if (b can inorder xmit) {
> > add mbuf b to inorder burst list
> > } else {
> > xmit inorder burst list
> > xmit mbuf b with normal xmit
> > }
> > }
> > if (inorder burst list not empty) {
> > xmit inorder burst list
> > }
> > update_avail_ring()
> >
> > Signed-off-by: Marvin Liu <yong.liu@intel.com>
> >
> > diff --git a/drivers/net/virtio/virtio_ethdev.h
> b/drivers/net/virtio/virtio_ethdev.h
> > index bb40064ea..25697c872 100644
> > --- a/drivers/net/virtio/virtio_ethdev.h
> > +++ b/drivers/net/virtio/virtio_ethdev.h
> > @@ -83,9 +83,15 @@ uint16_t virtio_recv_pkts(void *rx_queue, struct
> rte_mbuf **rx_pkts,
> > uint16_t virtio_recv_mergeable_pkts(void *rx_queue, struct rte_mbuf
> **rx_pkts,
> > uint16_t nb_pkts);
> >
> > +uint16_t virtio_recv_inorder_pkts(void *rx_queue, struct rte_mbuf
> **rx_pkts,
> > + uint16_t nb_pkts);
> > +
> > uint16_t virtio_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
> > uint16_t nb_pkts);
> >
> > +uint16_t virtio_xmit_inorder_pkts(void *tx_queue, struct rte_mbuf
> **tx_pkts,
> > + uint16_t nb_pkts);
> > +
> > uint16_t virtio_recv_pkts_vec(void *rx_queue, struct rte_mbuf **rx_pkts,
> > uint16_t nb_pkts);
> >
> > diff --git a/drivers/net/virtio/virtio_rxtx.c
> b/drivers/net/virtio/virtio_rxtx.c
> > index 0bca29855..d0473d6b4 100644
> > --- a/drivers/net/virtio/virtio_rxtx.c
> > +++ b/drivers/net/virtio/virtio_rxtx.c
> > @@ -122,6 +122,45 @@ virtqueue_dequeue_burst_rx(struct virtqueue *vq,
> struct rte_mbuf **rx_pkts,
> > return i;
> > }
> >
> > +static uint16_t
> > +virtqueue_dequeue_inorder_rx(struct virtqueue *vq,
>
> virtqueue_dequeue_burst_rx_inorder() will be better.
>
> > + struct rte_mbuf **rx_pkts,
> > + uint32_t *len,
> > + uint16_t num)
> > +{
> > + struct vring_used_elem *uep;
> > + struct rte_mbuf *cookie;
> > + uint16_t used_idx;
> > + uint16_t i;
> > +
> > + if (unlikely(num == 0))
> > + return 0;
> > +
> > + used_idx = vq->vq_used_cons_idx & (vq->vq_nentries - 1);
>
> Above assignment is misleading.
>
> > + for (i = 0; i < num; i++) {
> > + used_idx = vq->vq_used_cons_idx & (vq->vq_nentries - 1);
> > + /* Desc idx same as used idx */
> > + uep = &vq->vq_ring.used->ring[used_idx];
> > + len[i] = uep->len;
> > + cookie = (struct rte_mbuf *)vq->vq_descx[used_idx].cookie;
> > +
> > + if (unlikely(cookie == NULL)) {
> > + PMD_DRV_LOG(ERR, "vring descriptor with no mbuf cookie
> at %u",
> > + vq->vq_used_cons_idx);
> > + break;
> > + }
> > +
> > + rte_prefetch0(cookie);
> > + rte_packet_prefetch(rte_pktmbuf_mtod(cookie, void *));
> > + rx_pkts[i] = cookie;
> > + vq->vq_used_cons_idx++;
> > + vq->vq_descx[used_idx].cookie = NULL;
> > + }
> > +
> > + vq_ring_free_inorder(vq, used_idx, i);
> > + return i;
> > +}
> > +
> > #ifndef DEFAULT_TX_FREE_THRESH
> > #define DEFAULT_TX_FREE_THRESH 32
> > #endif
> > @@ -150,6 +189,70 @@ virtio_xmit_cleanup(struct virtqueue *vq, uint16_t
> num)
> > }
> > }
> >
> > +/* Cleanup from completed inorder transmits. */
> > +static void
> > +virtio_xmit_cleanup_inorder(struct virtqueue *vq, uint16_t num)
> > +{
> > + uint16_t i, used_idx;
> > +
> > + used_idx = vq->vq_used_cons_idx & (vq->vq_nentries - 1);
>
> Above assignment is misleading.
>
> > + for (i = 0; i < num; i++) {
> > + struct vq_desc_extra *dxp;
> > +
> > + used_idx = vq->vq_used_cons_idx & (vq->vq_nentries - 1);
> > + dxp = &vq->vq_descx[used_idx];
> > + vq->vq_used_cons_idx++;
> > +
> > + if (dxp->cookie != NULL) {
> > + rte_pktmbuf_free(dxp->cookie);
> > + dxp->cookie = NULL;
> > + }
> > + }
> > + vq_ring_free_inorder(vq, used_idx, num);
>
> If num is zero, we can't free used_idx.
>
> > +}
> > +
> > +static inline int
> > +virtqueue_enqueue_inorder_refill(struct virtqueue *vq,
>
> virtqueue_enqueue_recv_refill_inorder() will be better.
>
>
> > + struct rte_mbuf **cookies,
> > + uint16_t num)
> > +{
> > + struct vq_desc_extra *dxp;
> > + struct virtio_hw *hw = vq->hw;
> > + struct vring_desc *start_dp;
> > + uint16_t head_idx, idx, i = 0;
> > +
> > + if (unlikely(vq->vq_free_cnt == 0))
> > + return -ENOSPC;
> > + if (unlikely(vq->vq_free_cnt < num))
> > + return -EMSGSIZE;
> > +
> > + head_idx = vq->vq_desc_head_idx & (vq->vq_nentries - 1);
> > + start_dp = vq->vq_ring.desc;
> > +
> > + while (i < num) {
> > + idx = head_idx & (vq->vq_nentries - 1);
> > + dxp = &vq->vq_descx[idx];
> > + dxp->cookie = (void *)(struct rte_mbuf *)cookies[i];
>
> Casting isn't necessary.
>
> > + dxp->ndescs = 1;
> > +
> > + start_dp[idx].addr =
> > + VIRTIO_MBUF_ADDR(cookies[i], vq) +
> > + RTE_PKTMBUF_HEADROOM - hw->vtnet_hdr_size;
> > + start_dp[idx].len =
> > + cookies[i]->buf_len -
> > + RTE_PKTMBUF_HEADROOM +
> > + hw->vtnet_hdr_size;
> > + start_dp[idx].flags = VRING_DESC_F_WRITE;
> > +
> > + head_idx++;
> > + i++;
> > + }
> > +
> > + vq->vq_avail_idx += num;
> > + vq->vq_desc_head_idx += num;
> > + vq->vq_free_cnt = (uint16_t)(vq->vq_free_cnt - num);
> > + return 0;
> > +}
> >
> > static inline int
> > virtqueue_enqueue_recv_refill(struct virtqueue *vq, struct rte_mbuf
> *cookie)
> > @@ -246,9 +349,113 @@ tx_offload_enabled(struct virtio_hw *hw)
> > (var) = (val); \
> > } while (0)
> >
> [...]
> > +
> > +static void
> > +virtio_discard_inorder_rxbuf(struct virtqueue *vq, struct rte_mbuf *m)
>
> virtio_discard_rxbuf_inorder() will be better.
>
> > +{
> > + int error;
> > +
> > + error = virtqueue_enqueue_inorder_refill(vq, &m, 1);
> > if (unlikely(error)) {
> > RTE_LOG(ERR, PMD, "cannot requeue discarded mbuf");
> > rte_pktmbuf_free(m);
> > @@ -813,6 +1002,191 @@ virtio_recv_pkts(void *rx_queue, struct rte_mbuf
> **rx_pkts, uint16_t nb_pkts)
> > return nb_rx;
> > }
> >
> > +uint16_t
> > +virtio_recv_inorder_pkts(void *rx_queue,
>
> virtio_recv_mergeable_pkts_inorder() will be better.
>
> > + struct rte_mbuf **rx_pkts,
> > + uint16_t nb_pkts)
> > +{
> > + struct virtnet_rx *rxvq = rx_queue;
> > + struct virtqueue *vq = rxvq->vq;
> > + struct virtio_hw *hw = vq->hw;
> > + struct rte_mbuf *rxm;
> > + struct rte_mbuf *prev;
> > + uint16_t nb_used, num, nb_rx;
> > + uint32_t len[VIRTIO_MBUF_BURST_SZ];
> > + struct rte_mbuf *rcv_pkts[VIRTIO_MBUF_BURST_SZ];
> > + int error;
> > + uint32_t i, nb_enqueued;
> > + uint32_t seg_num;
> > + uint32_t seg_res;
> > + uint32_t hdr_size;
> > + int offload;
> > +
> > + nb_rx = 0;
> > + if (unlikely(hw->started == 0))
> > + return nb_rx;
> > +
> > + nb_used = VIRTQUEUE_NUSED(vq);
> > + nb_used = RTE_MIN(nb_used, nb_pkts);
> > + nb_used = RTE_MIN(nb_used, VIRTIO_MBUF_BURST_SZ);
> > +
> > + virtio_rmb();
> > +
> > + PMD_RX_LOG(DEBUG, "used:%d", nb_used);
> > +
> > + i = 0;
> > + nb_enqueued = 0;
> > + seg_num = 1;
> > + seg_res = 0;
> > + hdr_size = hw->vtnet_hdr_size;
> > + offload = rx_offload_enabled(hw);
> > +
> > + num = virtqueue_dequeue_inorder_rx(vq, rcv_pkts, len, nb_used);
> > +
> > + for (; i < num; i++) {
>
> Why not initialize i in for ()?
>
> > + struct virtio_net_hdr_mrg_rxbuf *header;
> > +
> > + PMD_RX_LOG(DEBUG, "dequeue:%d", num);
> > + PMD_RX_LOG(DEBUG, "packet len:%d", len[i]);
> > +
> > + rxm = rcv_pkts[i];
> > +
> > + if (unlikely(len[i] < hdr_size + ETHER_HDR_LEN)) {
> > + PMD_RX_LOG(ERR, "Packet drop");
> > + nb_enqueued++;
> > + virtio_discard_inorder_rxbuf(vq, rxm);
> > + rxvq->stats.errors++;
> > + continue;
> > + }
> > +
> > + header = (struct virtio_net_hdr_mrg_rxbuf *)((char *)rxm-
> >buf_addr +
> > + RTE_PKTMBUF_HEADROOM - hdr_size);
> > + seg_num = header->num_buffers;
> > +
> > + if (seg_num == 0)
> > + seg_num = 1;
> > +
> > + rxm->data_off = RTE_PKTMBUF_HEADROOM;
> > + rxm->nb_segs = seg_num;
> > + rxm->ol_flags = 0;
> > + rxm->vlan_tci = 0;
> > + rxm->pkt_len = (uint32_t)(len[i] - hdr_size);
> > + rxm->data_len = (uint16_t)(len[i] - hdr_size);
> > +
> > + rxm->port = rxvq->port_id;
> > +
> > + rx_pkts[nb_rx] = rxm;
> > + prev = rxm;
> > +
> > + if (offload && virtio_rx_offload(rxm, &header->hdr) < 0) {
> > + virtio_discard_inorder_rxbuf(vq, rxm);
> > + rxvq->stats.errors++;
> > + continue;
> > + }
> > +
> > + seg_res = seg_num - 1;
> > +
> > + /* Merge remaining segments */
> > + while (seg_res != 0 && i < num) {
> > + rxm = rcv_pkts[i];
> > + rxm->data_off = RTE_PKTMBUF_HEADROOM - hdr_size;
> > + rxm->pkt_len = (uint32_t)(len[i]);
> > + rxm->data_len = (uint16_t)(len[i]);
> > +
> > + rx_pkts[nb_rx]->pkt_len += (uint32_t)(len[i]);
> > + rx_pkts[nb_rx]->data_len += (uint16_t)(len[i]);
> > +
> > + i++;
> > +
> > + if (prev)
> > + prev->next = rxm;
> > +
> > + prev = rxm;
> > + seg_res -= 1;
> > + }
> > +
> > + if (hw->vlan_strip)
> > + rte_vlan_strip(rx_pkts[nb_rx]);
> > +
> > + VIRTIO_DUMP_PACKET(rx_pkts[nb_rx],
> > + rx_pkts[nb_rx]->data_len);
> > +
> > + rxvq->stats.bytes += rx_pkts[nb_rx]->pkt_len;
> > + virtio_update_packet_stats(&rxvq->stats, rx_pkts[nb_rx]);
>
> When seg_res != 0, we cannot run above code.
>
> > + nb_rx++;
> > + }
> > +
> > + /* Last packet still need merge segments */
> > + while (seg_res != 0) {
> > + uint16_t rcv_cnt = RTE_MIN((uint16_t)seg_res,
> > + VIRTIO_MBUF_BURST_SZ);
> > +
> > + prev = rcv_pkts[nb_rx - 1];
> > + if (likely(VIRTQUEUE_NUSED(vq) >= rcv_cnt)) {
> > + num = virtqueue_dequeue_inorder_rx(vq, rcv_pkts, len,
> > + rcv_cnt);
> > + uint16_t extra_idx = 0;
> > +
> > + rcv_cnt = num;
> > + while (extra_idx < rcv_cnt) {
> > + rxm = rcv_pkts[extra_idx];
> > + rxm->data_off = RTE_PKTMBUF_HEADROOM - hdr_size;
> > + rxm->pkt_len = (uint32_t)(len[extra_idx]);
> > + rxm->data_len = (uint16_t)(len[extra_idx]);
> > + prev->next = rxm;
> > + prev = rxm;
> > + rx_pkts[nb_rx - 1]->pkt_len += len[extra_idx];
> > + rx_pkts[nb_rx - 1]->data_len += len[extra_idx];
> > + extra_idx += 1;
> > + };
> > + seg_res -= rcv_cnt;
> > + } else {
> > + PMD_RX_LOG(ERR,
> > + "No enough segments for packet.");
> > + virtio_discard_inorder_rxbuf(vq, prev);
> > + rxvq->stats.errors++;
> > + nb_rx--;
> > + break;
> > + }
> > + }
> > +
> > + rxvq->stats.packets += nb_rx;
> > +
> > + /* Allocate new mbuf for the used descriptor */
> > + error = ENOSPC;
>
> Above assignment is meaningless.
Thanks, Will remove it in V2.
>
> > +
> > + if (likely(!virtqueue_full(vq))) {
> > + /* free_cnt may include mrg descs */
> > + uint16_t free_cnt = vq->vq_free_cnt;
> > + struct rte_mbuf *new_pkts[free_cnt];
> > +
> > + if (!rte_pktmbuf_alloc_bulk(rxvq->mpool, new_pkts, free_cnt))
> {
> > + error = virtqueue_enqueue_inorder_refill(vq, new_pkts,
> > + free_cnt);
> > + if (unlikely(error)) {
> > + for (i = 0; i < free_cnt; i++)
> > + rte_pktmbuf_free(new_pkts[i]);
> > + }
> > + nb_enqueued += free_cnt;
> > + } else {
> > + struct rte_eth_dev *dev
> > + = &rte_eth_devices[rxvq->port_id];
> > + dev->data->rx_mbuf_alloc_failed += free_cnt;
> > + }
> > + }
> > +
> > + if (likely(nb_enqueued)) {
> > + vq_update_avail_idx(vq);
> > +
> > + if (unlikely(virtqueue_kick_prepare(vq))) {
> > + virtqueue_notify(vq);
> > + PMD_RX_LOG(DEBUG, "Notified");
> > + }
> > + }
> > +
> > + return nb_rx;
> > +}
> > +
> > uint16_t
> > virtio_recv_mergeable_pkts(void *rx_queue,
> > struct rte_mbuf **rx_pkts,
> > @@ -1060,7 +1434,8 @@ virtio_xmit_pkts(void *tx_queue, struct rte_mbuf
> **tx_pkts, uint16_t nb_pkts)
> > }
> >
> > /* Enqueue Packet buffers */
> > - virtqueue_enqueue_xmit(txvq, txm, slots, use_indirect,
> can_push);
> > + virtqueue_enqueue_xmit(txvq, txm, slots, use_indirect,
> > + can_push, 0);
> >
> > txvq->stats.bytes += txm->pkt_len;
> > virtio_update_packet_stats(&txvq->stats, txm);
> > @@ -1079,3 +1454,121 @@ virtio_xmit_pkts(void *tx_queue, struct rte_mbuf
> **tx_pkts, uint16_t nb_pkts)
> >
> > return nb_tx;
> > }
> > +
> > +uint16_t
> > +virtio_xmit_inorder_pkts(void *tx_queue,
>
> virtio_xmit_pkts_inorder() will be better.
>
> > + struct rte_mbuf **tx_pkts,
> > + uint16_t nb_pkts)
> > +{
> > + struct virtnet_tx *txvq = tx_queue;
> > + struct virtqueue *vq = txvq->vq;
> > + struct virtio_hw *hw = vq->hw;
> > + uint16_t hdr_size = hw->vtnet_hdr_size;
> > + uint16_t nb_used, nb_avail, nb_tx = 0, inorder_tx = 0;
> > + struct rte_mbuf *inorder_pkts[nb_pkts];
> > + int error;
> > +
> > + if (unlikely(hw->started == 0 && tx_pkts != hw->inject_pkts))
> > + return nb_tx;
> > +
> > + if (unlikely(nb_pkts < 1))
> > + return nb_pkts;
> > +
> > + VIRTQUEUE_DUMP(vq);
> > + PMD_TX_LOG(DEBUG, "%d packets to xmit", nb_pkts);
> > + nb_used = VIRTQUEUE_NUSED(vq);
> > +
> > + virtio_rmb();
> > + if (likely(nb_used > vq->vq_nentries - vq->vq_free_thresh))
> > + virtio_xmit_cleanup_inorder(vq, nb_used);
> > +
> > + nb_avail = RTE_MIN(vq->vq_free_cnt, nb_pkts);
> > +
> > + for (nb_tx = 0; nb_tx < nb_avail; nb_tx++) {
> > + struct rte_mbuf *txm = tx_pkts[nb_tx];
> > + int slots, need;
> > + int can_push = 0, use_indirect = 0, flush_inorder = 1;
> > +
> > + /* Do VLAN tag insertion */
> > + if (unlikely(txm->ol_flags & PKT_TX_VLAN_PKT)) {
> > + error = rte_vlan_insert(&txm);
> > + if (unlikely(error)) {
> > + rte_pktmbuf_free(txm);
> > + continue;
> > + }
> > + }
> > +
> > + txvq->stats.bytes += txm->pkt_len;
> > + virtio_update_packet_stats(&txvq->stats, txm);
> > +
> > + /* optimize ring usage */
> > + if ((vtpci_with_feature(hw, VIRTIO_F_ANY_LAYOUT) ||
> > + vtpci_with_feature(hw, VIRTIO_F_VERSION_1)) &&
> > + rte_mbuf_refcnt_read(txm) == 1 &&
> > + RTE_MBUF_DIRECT(txm) &&
> > + txm->nb_segs == 1 &&
> > + rte_pktmbuf_headroom(txm) >= hdr_size &&
> > + rte_is_aligned(rte_pktmbuf_mtod(txm, char *),
> > + __alignof__(struct virtio_net_hdr_mrg_rxbuf))) {
> > + can_push = 1;
>
> There is no need to have 'can_push' any more.
>
> > +
> > + inorder_pkts[inorder_tx] = txm;
> > + inorder_tx++;
>
> inorder_tx isn't a good name.
>
> > + flush_inorder = 0;
>
> I think there is no need to introduce 'flush_inorder'.
> And it will make the code much more readable by writing
> the code like:
>
> for (nb_tx = 0; nb_tx < nb_avail; nb_tx++) {
> struct rte_mbuf *txm = tx_pkts[nb_tx];
>
> ......
>
> if ((vtpci_with_feature(hw, VIRTIO_F_ANY_LAYOUT) ||
> vtpci_with_feature(hw, VIRTIO_F_VERSION_1)) &&
> rte_mbuf_refcnt_read(txm) == 1 &&
> RTE_MBUF_DIRECT(txm) &&
> txm->nb_segs == 1 &&
> rte_pktmbuf_headroom(txm) >= hdr_size &&
> rte_is_aligned(rte_pktmbuf_mtod(txm, char *),
> __alignof__(struct virtio_net_hdr_mrg_rxbuf))) {
>
> inorder_pkts[nb_inorder_pkts++] = txm;
> continue;
> }
>
> /* Flush inorder packets if any. */
> if (nb_inorder_pkts) {
> virtqueue_enqueue_xmit_inorder(txvq, inorder_pkts,
> nb_inorder_pkts);
> nb_inorder_pkts = 0;
> }
>
> ......
>
> virtqueue_enqueue_xmit(txvq, txm, slots, 0, 0, 1);
> }
Thanks Tiwei, this logic is more clear. Will modified in V2.
>
> /* Flush inorder packets if any. */
> if (nb_inorder_pkts) {
> virtqueue_enqueue_xmit_inorder(txvq, inorder_pkts,
> nb_inorder_pkts);
> nb_inorder_pkts = 0;
> }
>
>
>
> > + } else if (vtpci_with_feature(hw, VIRTIO_RING_F_INDIRECT_DESC)
> &&
> > + txm->nb_segs < VIRTIO_MAX_TX_INDIRECT) {
> > + use_indirect = 1;
> > + }
>
> There is no need to try to use INDIRECT.
>
> > +
> > + if (flush_inorder) {
> > + /* Flush inorder packets */
> > + virtqueue_enqueue_xmit_inorder(txvq, inorder_pkts,
> > + inorder_tx);
> > + inorder_tx = 0;
> > +
> > + /* How many main ring entries are needed to this Tx?
> > + * any_layout => number of segments
> > + * indirect => 1
> > + * default => number of segments + 1
> > + */
> > + slots = use_indirect ? 1 : (txm->nb_segs + !can_push);
> > + need = slots - vq->vq_free_cnt;
> > +
> > + if (unlikely(need > 0)) {
> > + nb_used = VIRTQUEUE_NUSED(vq);
> > + virtio_rmb();
> > + need = RTE_MIN(need, (int)nb_used);
> > +
> > + virtio_xmit_cleanup_inorder(vq, need);
> > + need = slots - vq->vq_free_cnt;
> > + if (unlikely(need > 0)) {
> > + PMD_TX_LOG(ERR,
> > + "No free tx descriptors to transmit");
> > + break;
> > + }
> > + }
> > + /* Enqueue Packet buffers */
> > + virtqueue_enqueue_xmit(txvq, txm, slots, use_indirect,
> > + can_push, 1);
> > + }
> > + }
> > +
> > + /* Transmit all inorder packets */
> > + if (inorder_tx)
> > + virtqueue_enqueue_xmit_inorder(txvq, inorder_pkts, inorder_tx);
> > +
> > + txvq->stats.packets += nb_tx;
> > +
> > + if (likely(nb_tx)) {
> > + vq_update_avail_idx(vq);
> > +
> > + if (unlikely(virtqueue_kick_prepare(vq))) {
> > + virtqueue_notify(vq);
> > + PMD_TX_LOG(DEBUG, "Notified backend after xmit");
> > + }
> > + }
> > +
> > + VIRTQUEUE_DUMP(vq);
> > +
> > + return nb_tx;
> > +}
> > --
> > 2.17.0
> >
@@ -83,9 +83,15 @@ uint16_t virtio_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts,
uint16_t virtio_recv_mergeable_pkts(void *rx_queue, struct rte_mbuf **rx_pkts,
uint16_t nb_pkts);
+uint16_t virtio_recv_inorder_pkts(void *rx_queue, struct rte_mbuf **rx_pkts,
+ uint16_t nb_pkts);
+
uint16_t virtio_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
uint16_t nb_pkts);
+uint16_t virtio_xmit_inorder_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
+ uint16_t nb_pkts);
+
uint16_t virtio_recv_pkts_vec(void *rx_queue, struct rte_mbuf **rx_pkts,
uint16_t nb_pkts);
@@ -122,6 +122,45 @@ virtqueue_dequeue_burst_rx(struct virtqueue *vq, struct rte_mbuf **rx_pkts,
return i;
}
+static uint16_t
+virtqueue_dequeue_inorder_rx(struct virtqueue *vq,
+ struct rte_mbuf **rx_pkts,
+ uint32_t *len,
+ uint16_t num)
+{
+ struct vring_used_elem *uep;
+ struct rte_mbuf *cookie;
+ uint16_t used_idx;
+ uint16_t i;
+
+ if (unlikely(num == 0))
+ return 0;
+
+ used_idx = vq->vq_used_cons_idx & (vq->vq_nentries - 1);
+ for (i = 0; i < num; i++) {
+ used_idx = vq->vq_used_cons_idx & (vq->vq_nentries - 1);
+ /* Desc idx same as used idx */
+ uep = &vq->vq_ring.used->ring[used_idx];
+ len[i] = uep->len;
+ cookie = (struct rte_mbuf *)vq->vq_descx[used_idx].cookie;
+
+ if (unlikely(cookie == NULL)) {
+ PMD_DRV_LOG(ERR, "vring descriptor with no mbuf cookie at %u",
+ vq->vq_used_cons_idx);
+ break;
+ }
+
+ rte_prefetch0(cookie);
+ rte_packet_prefetch(rte_pktmbuf_mtod(cookie, void *));
+ rx_pkts[i] = cookie;
+ vq->vq_used_cons_idx++;
+ vq->vq_descx[used_idx].cookie = NULL;
+ }
+
+ vq_ring_free_inorder(vq, used_idx, i);
+ return i;
+}
+
#ifndef DEFAULT_TX_FREE_THRESH
#define DEFAULT_TX_FREE_THRESH 32
#endif
@@ -150,6 +189,70 @@ virtio_xmit_cleanup(struct virtqueue *vq, uint16_t num)
}
}
+/* Cleanup from completed inorder transmits. */
+static void
+virtio_xmit_cleanup_inorder(struct virtqueue *vq, uint16_t num)
+{
+ uint16_t i, used_idx;
+
+ used_idx = vq->vq_used_cons_idx & (vq->vq_nentries - 1);
+ for (i = 0; i < num; i++) {
+ struct vq_desc_extra *dxp;
+
+ used_idx = vq->vq_used_cons_idx & (vq->vq_nentries - 1);
+ dxp = &vq->vq_descx[used_idx];
+ vq->vq_used_cons_idx++;
+
+ if (dxp->cookie != NULL) {
+ rte_pktmbuf_free(dxp->cookie);
+ dxp->cookie = NULL;
+ }
+ }
+ vq_ring_free_inorder(vq, used_idx, num);
+}
+
+static inline int
+virtqueue_enqueue_inorder_refill(struct virtqueue *vq,
+ struct rte_mbuf **cookies,
+ uint16_t num)
+{
+ struct vq_desc_extra *dxp;
+ struct virtio_hw *hw = vq->hw;
+ struct vring_desc *start_dp;
+ uint16_t head_idx, idx, i = 0;
+
+ if (unlikely(vq->vq_free_cnt == 0))
+ return -ENOSPC;
+ if (unlikely(vq->vq_free_cnt < num))
+ return -EMSGSIZE;
+
+ head_idx = vq->vq_desc_head_idx & (vq->vq_nentries - 1);
+ start_dp = vq->vq_ring.desc;
+
+ while (i < num) {
+ idx = head_idx & (vq->vq_nentries - 1);
+ dxp = &vq->vq_descx[idx];
+ dxp->cookie = (void *)(struct rte_mbuf *)cookies[i];
+ dxp->ndescs = 1;
+
+ start_dp[idx].addr =
+ VIRTIO_MBUF_ADDR(cookies[i], vq) +
+ RTE_PKTMBUF_HEADROOM - hw->vtnet_hdr_size;
+ start_dp[idx].len =
+ cookies[i]->buf_len -
+ RTE_PKTMBUF_HEADROOM +
+ hw->vtnet_hdr_size;
+ start_dp[idx].flags = VRING_DESC_F_WRITE;
+
+ head_idx++;
+ i++;
+ }
+
+ vq->vq_avail_idx += num;
+ vq->vq_desc_head_idx += num;
+ vq->vq_free_cnt = (uint16_t)(vq->vq_free_cnt - num);
+ return 0;
+}
static inline int
virtqueue_enqueue_recv_refill(struct virtqueue *vq, struct rte_mbuf *cookie)
@@ -246,9 +349,113 @@ tx_offload_enabled(struct virtio_hw *hw)
(var) = (val); \
} while (0)
+static inline void
+virtqueue_xmit_offload(struct virtio_net_hdr *hdr,
+ struct rte_mbuf *cookie,
+ int offload)
+{
+ if (offload) {
+ if (cookie->ol_flags & PKT_TX_TCP_SEG)
+ cookie->ol_flags |= PKT_TX_TCP_CKSUM;
+
+ switch (cookie->ol_flags & PKT_TX_L4_MASK) {
+ case PKT_TX_UDP_CKSUM:
+ hdr->csum_start = cookie->l2_len + cookie->l3_len;
+ hdr->csum_offset = offsetof(struct udp_hdr,
+ dgram_cksum);
+ hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
+ break;
+
+ case PKT_TX_TCP_CKSUM:
+ hdr->csum_start = cookie->l2_len + cookie->l3_len;
+ hdr->csum_offset = offsetof(struct tcp_hdr, cksum);
+ hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
+ break;
+
+ default:
+ ASSIGN_UNLESS_EQUAL(hdr->csum_start, 0);
+ ASSIGN_UNLESS_EQUAL(hdr->csum_offset, 0);
+ ASSIGN_UNLESS_EQUAL(hdr->flags, 0);
+ break;
+ }
+
+ /* TCP Segmentation Offload */
+ if (cookie->ol_flags & PKT_TX_TCP_SEG) {
+ virtio_tso_fix_cksum(cookie);
+ hdr->gso_type = (cookie->ol_flags & PKT_TX_IPV6) ?
+ VIRTIO_NET_HDR_GSO_TCPV6 :
+ VIRTIO_NET_HDR_GSO_TCPV4;
+ hdr->gso_size = cookie->tso_segsz;
+ hdr->hdr_len =
+ cookie->l2_len +
+ cookie->l3_len +
+ cookie->l4_len;
+ } else {
+ ASSIGN_UNLESS_EQUAL(hdr->gso_type, 0);
+ ASSIGN_UNLESS_EQUAL(hdr->gso_size, 0);
+ ASSIGN_UNLESS_EQUAL(hdr->hdr_len, 0);
+ }
+ }
+}
+
+static inline void
+virtqueue_enqueue_xmit_inorder(struct virtnet_tx *txvq,
+ struct rte_mbuf **cookies,
+ uint16_t num)
+{
+ struct vq_desc_extra *dxp;
+ struct virtqueue *vq = txvq->vq;
+ struct vring_desc *start_dp;
+ struct virtio_net_hdr *hdr;
+ uint16_t idx;
+ uint16_t head_size = vq->hw->vtnet_hdr_size;
+ int offload;
+ uint16_t i = 0;
+
+ idx = vq->vq_desc_head_idx;
+ start_dp = vq->vq_ring.desc;
+
+ offload = tx_offload_enabled(vq->hw);
+
+ while (i < num) {
+ idx = idx & (vq->vq_nentries - 1);
+ dxp = &vq->vq_descx[idx];
+ dxp->cookie = (void *)cookies[i];
+ dxp->ndescs = 1;
+
+ hdr = (struct virtio_net_hdr *)
+ rte_pktmbuf_prepend(cookies[i], head_size);
+ cookies[i]->pkt_len -= head_size;
+
+ /* if offload disabled, it is not zeroed below, do it now */
+ if (offload == 0) {
+ ASSIGN_UNLESS_EQUAL(hdr->csum_start, 0);
+ ASSIGN_UNLESS_EQUAL(hdr->csum_offset, 0);
+ ASSIGN_UNLESS_EQUAL(hdr->flags, 0);
+ ASSIGN_UNLESS_EQUAL(hdr->gso_type, 0);
+ ASSIGN_UNLESS_EQUAL(hdr->gso_size, 0);
+ ASSIGN_UNLESS_EQUAL(hdr->hdr_len, 0);
+ }
+
+ virtqueue_xmit_offload(hdr, cookies[i], offload);
+
+ start_dp[idx].addr = VIRTIO_MBUF_DATA_DMA_ADDR(cookies[i], vq);
+ start_dp[idx].len = cookies[i]->data_len;
+ start_dp[idx].flags = 0;
+
+ idx++;
+ i++;
+ };
+
+ vq->vq_free_cnt = (uint16_t)(vq->vq_free_cnt - num);
+ vq->vq_desc_head_idx = idx & (vq->vq_nentries - 1);
+ vq->vq_avail_idx += num;
+}
+
static inline void
virtqueue_enqueue_xmit(struct virtnet_tx *txvq, struct rte_mbuf *cookie,
- uint16_t needed, int use_indirect, int can_push)
+ uint16_t needed, int use_indirect, int can_push,
+ int in_order)
{
struct virtio_tx_region *txr = txvq->virtio_net_hdr_mz->addr;
struct vq_desc_extra *dxp;
@@ -261,6 +468,7 @@ virtqueue_enqueue_xmit(struct virtnet_tx *txvq, struct rte_mbuf *cookie,
int offload;
offload = tx_offload_enabled(vq->hw);
+
head_idx = vq->vq_desc_head_idx;
idx = head_idx;
dxp = &vq->vq_descx[idx];
@@ -277,6 +485,7 @@ virtqueue_enqueue_xmit(struct virtnet_tx *txvq, struct rte_mbuf *cookie,
* which is wrong. Below subtract restores correct pkt size.
*/
cookie->pkt_len -= head_size;
+
/* if offload disabled, it is not zeroed below, do it now */
if (offload == 0) {
ASSIGN_UNLESS_EQUAL(hdr->csum_start, 0);
@@ -315,49 +524,7 @@ virtqueue_enqueue_xmit(struct virtnet_tx *txvq, struct rte_mbuf *cookie,
idx = start_dp[idx].next;
}
- /* Checksum Offload / TSO */
- if (offload) {
- if (cookie->ol_flags & PKT_TX_TCP_SEG)
- cookie->ol_flags |= PKT_TX_TCP_CKSUM;
-
- switch (cookie->ol_flags & PKT_TX_L4_MASK) {
- case PKT_TX_UDP_CKSUM:
- hdr->csum_start = cookie->l2_len + cookie->l3_len;
- hdr->csum_offset = offsetof(struct udp_hdr,
- dgram_cksum);
- hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
- break;
-
- case PKT_TX_TCP_CKSUM:
- hdr->csum_start = cookie->l2_len + cookie->l3_len;
- hdr->csum_offset = offsetof(struct tcp_hdr, cksum);
- hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
- break;
-
- default:
- ASSIGN_UNLESS_EQUAL(hdr->csum_start, 0);
- ASSIGN_UNLESS_EQUAL(hdr->csum_offset, 0);
- ASSIGN_UNLESS_EQUAL(hdr->flags, 0);
- break;
- }
-
- /* TCP Segmentation Offload */
- if (cookie->ol_flags & PKT_TX_TCP_SEG) {
- virtio_tso_fix_cksum(cookie);
- hdr->gso_type = (cookie->ol_flags & PKT_TX_IPV6) ?
- VIRTIO_NET_HDR_GSO_TCPV6 :
- VIRTIO_NET_HDR_GSO_TCPV4;
- hdr->gso_size = cookie->tso_segsz;
- hdr->hdr_len =
- cookie->l2_len +
- cookie->l3_len +
- cookie->l4_len;
- } else {
- ASSIGN_UNLESS_EQUAL(hdr->gso_type, 0);
- ASSIGN_UNLESS_EQUAL(hdr->gso_size, 0);
- ASSIGN_UNLESS_EQUAL(hdr->hdr_len, 0);
- }
- }
+ virtqueue_xmit_offload(hdr, cookie, offload);
do {
start_dp[idx].addr = VIRTIO_MBUF_DATA_DMA_ADDR(cookie, vq);
@@ -369,11 +536,20 @@ virtqueue_enqueue_xmit(struct virtnet_tx *txvq, struct rte_mbuf *cookie,
if (use_indirect)
idx = vq->vq_ring.desc[head_idx].next;
- vq->vq_desc_head_idx = idx;
- if (vq->vq_desc_head_idx == VQ_RING_DESC_CHAIN_END)
- vq->vq_desc_tail_idx = idx;
vq->vq_free_cnt = (uint16_t)(vq->vq_free_cnt - needed);
- vq_update_avail_ring(vq, head_idx);
+
+ if (in_order) {
+ if (likely(use_indirect))
+ vq->vq_avail_idx++;
+ else
+ vq->vq_avail_idx += needed;
+ vq->vq_desc_head_idx = idx & (vq->vq_nentries - 1);
+ } else {
+ vq->vq_desc_head_idx = idx;
+ if (vq->vq_desc_head_idx == VQ_RING_DESC_CHAIN_END)
+ vq->vq_desc_tail_idx = idx;
+ vq_update_avail_ring(vq, head_idx);
+ }
}
void
@@ -583,6 +759,19 @@ virtio_discard_rxbuf(struct virtqueue *vq, struct rte_mbuf *m)
* successful since it was just dequeued.
*/
error = virtqueue_enqueue_recv_refill(vq, m);
+
+ if (unlikely(error)) {
+ RTE_LOG(ERR, PMD, "cannot requeue discarded mbuf");
+ rte_pktmbuf_free(m);
+ }
+}
+
+static void
+virtio_discard_inorder_rxbuf(struct virtqueue *vq, struct rte_mbuf *m)
+{
+ int error;
+
+ error = virtqueue_enqueue_inorder_refill(vq, &m, 1);
if (unlikely(error)) {
RTE_LOG(ERR, PMD, "cannot requeue discarded mbuf");
rte_pktmbuf_free(m);
@@ -813,6 +1002,191 @@ virtio_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts, uint16_t nb_pkts)
return nb_rx;
}
+uint16_t
+virtio_recv_inorder_pkts(void *rx_queue,
+ struct rte_mbuf **rx_pkts,
+ uint16_t nb_pkts)
+{
+ struct virtnet_rx *rxvq = rx_queue;
+ struct virtqueue *vq = rxvq->vq;
+ struct virtio_hw *hw = vq->hw;
+ struct rte_mbuf *rxm;
+ struct rte_mbuf *prev;
+ uint16_t nb_used, num, nb_rx;
+ uint32_t len[VIRTIO_MBUF_BURST_SZ];
+ struct rte_mbuf *rcv_pkts[VIRTIO_MBUF_BURST_SZ];
+ int error;
+ uint32_t i, nb_enqueued;
+ uint32_t seg_num;
+ uint32_t seg_res;
+ uint32_t hdr_size;
+ int offload;
+
+ nb_rx = 0;
+ if (unlikely(hw->started == 0))
+ return nb_rx;
+
+ nb_used = VIRTQUEUE_NUSED(vq);
+ nb_used = RTE_MIN(nb_used, nb_pkts);
+ nb_used = RTE_MIN(nb_used, VIRTIO_MBUF_BURST_SZ);
+
+ virtio_rmb();
+
+ PMD_RX_LOG(DEBUG, "used:%d", nb_used);
+
+ i = 0;
+ nb_enqueued = 0;
+ seg_num = 1;
+ seg_res = 0;
+ hdr_size = hw->vtnet_hdr_size;
+ offload = rx_offload_enabled(hw);
+
+ num = virtqueue_dequeue_inorder_rx(vq, rcv_pkts, len, nb_used);
+
+ for (; i < num; i++) {
+ struct virtio_net_hdr_mrg_rxbuf *header;
+
+ PMD_RX_LOG(DEBUG, "dequeue:%d", num);
+ PMD_RX_LOG(DEBUG, "packet len:%d", len[i]);
+
+ rxm = rcv_pkts[i];
+
+ if (unlikely(len[i] < hdr_size + ETHER_HDR_LEN)) {
+ PMD_RX_LOG(ERR, "Packet drop");
+ nb_enqueued++;
+ virtio_discard_inorder_rxbuf(vq, rxm);
+ rxvq->stats.errors++;
+ continue;
+ }
+
+ header = (struct virtio_net_hdr_mrg_rxbuf *)((char *)rxm->buf_addr +
+ RTE_PKTMBUF_HEADROOM - hdr_size);
+ seg_num = header->num_buffers;
+
+ if (seg_num == 0)
+ seg_num = 1;
+
+ rxm->data_off = RTE_PKTMBUF_HEADROOM;
+ rxm->nb_segs = seg_num;
+ rxm->ol_flags = 0;
+ rxm->vlan_tci = 0;
+ rxm->pkt_len = (uint32_t)(len[i] - hdr_size);
+ rxm->data_len = (uint16_t)(len[i] - hdr_size);
+
+ rxm->port = rxvq->port_id;
+
+ rx_pkts[nb_rx] = rxm;
+ prev = rxm;
+
+ if (offload && virtio_rx_offload(rxm, &header->hdr) < 0) {
+ virtio_discard_inorder_rxbuf(vq, rxm);
+ rxvq->stats.errors++;
+ continue;
+ }
+
+ seg_res = seg_num - 1;
+
+ /* Merge remaining segments */
+ while (seg_res != 0 && i < num) {
+ rxm = rcv_pkts[i];
+ rxm->data_off = RTE_PKTMBUF_HEADROOM - hdr_size;
+ rxm->pkt_len = (uint32_t)(len[i]);
+ rxm->data_len = (uint16_t)(len[i]);
+
+ rx_pkts[nb_rx]->pkt_len += (uint32_t)(len[i]);
+ rx_pkts[nb_rx]->data_len += (uint16_t)(len[i]);
+
+ i++;
+
+ if (prev)
+ prev->next = rxm;
+
+ prev = rxm;
+ seg_res -= 1;
+ }
+
+ if (hw->vlan_strip)
+ rte_vlan_strip(rx_pkts[nb_rx]);
+
+ VIRTIO_DUMP_PACKET(rx_pkts[nb_rx],
+ rx_pkts[nb_rx]->data_len);
+
+ rxvq->stats.bytes += rx_pkts[nb_rx]->pkt_len;
+ virtio_update_packet_stats(&rxvq->stats, rx_pkts[nb_rx]);
+ nb_rx++;
+ }
+
+ /* Last packet still need merge segments */
+ while (seg_res != 0) {
+ uint16_t rcv_cnt = RTE_MIN((uint16_t)seg_res,
+ VIRTIO_MBUF_BURST_SZ);
+
+ prev = rcv_pkts[nb_rx - 1];
+ if (likely(VIRTQUEUE_NUSED(vq) >= rcv_cnt)) {
+ num = virtqueue_dequeue_inorder_rx(vq, rcv_pkts, len,
+ rcv_cnt);
+ uint16_t extra_idx = 0;
+
+ rcv_cnt = num;
+ while (extra_idx < rcv_cnt) {
+ rxm = rcv_pkts[extra_idx];
+ rxm->data_off = RTE_PKTMBUF_HEADROOM - hdr_size;
+ rxm->pkt_len = (uint32_t)(len[extra_idx]);
+ rxm->data_len = (uint16_t)(len[extra_idx]);
+ prev->next = rxm;
+ prev = rxm;
+ rx_pkts[nb_rx - 1]->pkt_len += len[extra_idx];
+ rx_pkts[nb_rx - 1]->data_len += len[extra_idx];
+ extra_idx += 1;
+ };
+ seg_res -= rcv_cnt;
+ } else {
+ PMD_RX_LOG(ERR,
+ "No enough segments for packet.");
+ virtio_discard_inorder_rxbuf(vq, prev);
+ rxvq->stats.errors++;
+ nb_rx--;
+ break;
+ }
+ }
+
+ rxvq->stats.packets += nb_rx;
+
+ /* Allocate new mbuf for the used descriptor */
+ error = ENOSPC;
+
+ if (likely(!virtqueue_full(vq))) {
+ /* free_cnt may include mrg descs */
+ uint16_t free_cnt = vq->vq_free_cnt;
+ struct rte_mbuf *new_pkts[free_cnt];
+
+ if (!rte_pktmbuf_alloc_bulk(rxvq->mpool, new_pkts, free_cnt)) {
+ error = virtqueue_enqueue_inorder_refill(vq, new_pkts,
+ free_cnt);
+ if (unlikely(error)) {
+ for (i = 0; i < free_cnt; i++)
+ rte_pktmbuf_free(new_pkts[i]);
+ }
+ nb_enqueued += free_cnt;
+ } else {
+ struct rte_eth_dev *dev
+ = &rte_eth_devices[rxvq->port_id];
+ dev->data->rx_mbuf_alloc_failed += free_cnt;
+ }
+ }
+
+ if (likely(nb_enqueued)) {
+ vq_update_avail_idx(vq);
+
+ if (unlikely(virtqueue_kick_prepare(vq))) {
+ virtqueue_notify(vq);
+ PMD_RX_LOG(DEBUG, "Notified");
+ }
+ }
+
+ return nb_rx;
+}
+
uint16_t
virtio_recv_mergeable_pkts(void *rx_queue,
struct rte_mbuf **rx_pkts,
@@ -1060,7 +1434,8 @@ virtio_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts, uint16_t nb_pkts)
}
/* Enqueue Packet buffers */
- virtqueue_enqueue_xmit(txvq, txm, slots, use_indirect, can_push);
+ virtqueue_enqueue_xmit(txvq, txm, slots, use_indirect,
+ can_push, 0);
txvq->stats.bytes += txm->pkt_len;
virtio_update_packet_stats(&txvq->stats, txm);
@@ -1079,3 +1454,121 @@ virtio_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts, uint16_t nb_pkts)
return nb_tx;
}
+
+uint16_t
+virtio_xmit_inorder_pkts(void *tx_queue,
+ struct rte_mbuf **tx_pkts,
+ uint16_t nb_pkts)
+{
+ struct virtnet_tx *txvq = tx_queue;
+ struct virtqueue *vq = txvq->vq;
+ struct virtio_hw *hw = vq->hw;
+ uint16_t hdr_size = hw->vtnet_hdr_size;
+ uint16_t nb_used, nb_avail, nb_tx = 0, inorder_tx = 0;
+ struct rte_mbuf *inorder_pkts[nb_pkts];
+ int error;
+
+ if (unlikely(hw->started == 0 && tx_pkts != hw->inject_pkts))
+ return nb_tx;
+
+ if (unlikely(nb_pkts < 1))
+ return nb_pkts;
+
+ VIRTQUEUE_DUMP(vq);
+ PMD_TX_LOG(DEBUG, "%d packets to xmit", nb_pkts);
+ nb_used = VIRTQUEUE_NUSED(vq);
+
+ virtio_rmb();
+ if (likely(nb_used > vq->vq_nentries - vq->vq_free_thresh))
+ virtio_xmit_cleanup_inorder(vq, nb_used);
+
+ nb_avail = RTE_MIN(vq->vq_free_cnt, nb_pkts);
+
+ for (nb_tx = 0; nb_tx < nb_avail; nb_tx++) {
+ struct rte_mbuf *txm = tx_pkts[nb_tx];
+ int slots, need;
+ int can_push = 0, use_indirect = 0, flush_inorder = 1;
+
+ /* Do VLAN tag insertion */
+ if (unlikely(txm->ol_flags & PKT_TX_VLAN_PKT)) {
+ error = rte_vlan_insert(&txm);
+ if (unlikely(error)) {
+ rte_pktmbuf_free(txm);
+ continue;
+ }
+ }
+
+ txvq->stats.bytes += txm->pkt_len;
+ virtio_update_packet_stats(&txvq->stats, txm);
+
+ /* optimize ring usage */
+ if ((vtpci_with_feature(hw, VIRTIO_F_ANY_LAYOUT) ||
+ vtpci_with_feature(hw, VIRTIO_F_VERSION_1)) &&
+ rte_mbuf_refcnt_read(txm) == 1 &&
+ RTE_MBUF_DIRECT(txm) &&
+ txm->nb_segs == 1 &&
+ rte_pktmbuf_headroom(txm) >= hdr_size &&
+ rte_is_aligned(rte_pktmbuf_mtod(txm, char *),
+ __alignof__(struct virtio_net_hdr_mrg_rxbuf))) {
+ can_push = 1;
+
+ inorder_pkts[inorder_tx] = txm;
+ inorder_tx++;
+ flush_inorder = 0;
+ } else if (vtpci_with_feature(hw, VIRTIO_RING_F_INDIRECT_DESC) &&
+ txm->nb_segs < VIRTIO_MAX_TX_INDIRECT) {
+ use_indirect = 1;
+ }
+
+ if (flush_inorder) {
+ /* Flush inorder packets */
+ virtqueue_enqueue_xmit_inorder(txvq, inorder_pkts,
+ inorder_tx);
+ inorder_tx = 0;
+
+ /* How many main ring entries are needed to this Tx?
+ * any_layout => number of segments
+ * indirect => 1
+ * default => number of segments + 1
+ */
+ slots = use_indirect ? 1 : (txm->nb_segs + !can_push);
+ need = slots - vq->vq_free_cnt;
+
+ if (unlikely(need > 0)) {
+ nb_used = VIRTQUEUE_NUSED(vq);
+ virtio_rmb();
+ need = RTE_MIN(need, (int)nb_used);
+
+ virtio_xmit_cleanup_inorder(vq, need);
+ need = slots - vq->vq_free_cnt;
+ if (unlikely(need > 0)) {
+ PMD_TX_LOG(ERR,
+ "No free tx descriptors to transmit");
+ break;
+ }
+ }
+ /* Enqueue Packet buffers */
+ virtqueue_enqueue_xmit(txvq, txm, slots, use_indirect,
+ can_push, 1);
+ }
+ }
+
+ /* Transmit all inorder packets */
+ if (inorder_tx)
+ virtqueue_enqueue_xmit_inorder(txvq, inorder_pkts, inorder_tx);
+
+ txvq->stats.packets += nb_tx;
+
+ if (likely(nb_tx)) {
+ vq_update_avail_idx(vq);
+
+ if (unlikely(virtqueue_kick_prepare(vq))) {
+ virtqueue_notify(vq);
+ PMD_TX_LOG(DEBUG, "Notified backend after xmit");
+ }
+ }
+
+ VIRTQUEUE_DUMP(vq);
+
+ return nb_tx;
+}