On Tue, Dec 11, 2018 at 02:48:04PM +0100, Maxime Coquelin wrote:
> This patch improves both descriptors dequeue and refill,
> by using the same bathing strategy as done in in-order path.
>
> Signed-off-by: Maxime Coquelin <maxime.coque...@redhat.com>
> ---
> drivers/net/virtio/virtio_rxtx.c | 237 ++++++++++++++++---------------
> 1 file changed, 126 insertions(+), 111 deletions(-)
>
> diff --git a/drivers/net/virtio/virtio_rxtx.c
> b/drivers/net/virtio/virtio_rxtx.c
> index ebe5c74b5..59bcac2f7 100644
> --- a/drivers/net/virtio/virtio_rxtx.c
> +++ b/drivers/net/virtio/virtio_rxtx.c
> @@ -267,41 +267,42 @@ virtqueue_enqueue_refill_inorder(struct virtqueue *vq,
> }
>
> static inline int
> -virtqueue_enqueue_recv_refill(struct virtqueue *vq, struct rte_mbuf *cookie)
> +virtqueue_enqueue_recv_refill(struct virtqueue *vq, struct rte_mbuf **cookie,
> + uint16_t num)
> {
> struct vq_desc_extra *dxp;
> struct virtio_hw *hw = vq->hw;
> - struct vring_desc *start_dp;
> - uint16_t needed = 1;
> - uint16_t head_idx, idx;
> + struct vring_desc *start_dp = vq->vq_ring.desc;
> + uint16_t idx, i;
>
> if (unlikely(vq->vq_free_cnt == 0))
> return -ENOSPC;
> - if (unlikely(vq->vq_free_cnt < needed))
> + if (unlikely(vq->vq_free_cnt < num))
> return -EMSGSIZE;
>
> - head_idx = vq->vq_desc_head_idx;
> - if (unlikely(head_idx >= vq->vq_nentries))
> + if (unlikely(vq->vq_desc_head_idx >= vq->vq_nentries))
> return -EFAULT;
>
> - idx = head_idx;
> - dxp = &vq->vq_descx[idx];
> - dxp->cookie = (void *)cookie;
> - dxp->ndescs = needed;
> + for (i = 0; i < num; i++) {
> + idx = vq->vq_desc_head_idx;
> + dxp = &vq->vq_descx[idx];
> + dxp->cookie = (void *)cookie[i];
> + dxp->ndescs = 1;
>
> - start_dp = vq->vq_ring.desc;
> - start_dp[idx].addr =
> - VIRTIO_MBUF_ADDR(cookie, vq) +
> - RTE_PKTMBUF_HEADROOM - hw->vtnet_hdr_size;
> - start_dp[idx].len =
> - cookie->buf_len - RTE_PKTMBUF_HEADROOM + hw->vtnet_hdr_size;
> - start_dp[idx].flags = VRING_DESC_F_WRITE;
> - idx = start_dp[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);
> + start_dp[idx].addr =
> + VIRTIO_MBUF_ADDR(cookie[i], vq) +
> + RTE_PKTMBUF_HEADROOM - hw->vtnet_hdr_size;
> + start_dp[idx].len =
> + cookie[i]->buf_len - RTE_PKTMBUF_HEADROOM +
> + hw->vtnet_hdr_size;
> + start_dp[idx].flags = VRING_DESC_F_WRITE;
> + vq->vq_desc_head_idx = start_dp[idx].next;
> + if (vq->vq_desc_head_idx == VQ_RING_DESC_CHAIN_END)
> + vq->vq_desc_tail_idx = vq->vq_desc_head_idx;
It's better to break the loop here. Or maybe move
this check out of the loop.
> + vq_update_avail_ring(vq, idx);
> + }
> +
> + vq->vq_free_cnt = (uint16_t)(vq->vq_free_cnt - num);
>
> return 0;
> }
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