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....@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
>
