> -----Original Message-----
> From: Maxime Coquelin <maxime.coque...@redhat.com>
> Sent: Wednesday, October 27, 2021 12:29 AM
> To: dev@dpdk.org; Xia, Chenbo <chenbo....@intel.com>; Hu, Jiayu
> <jiayu...@intel.com>; Wang, YuanX <yuanx.w...@intel.com>; Ma, WenwuX
> <wenwux...@intel.com>; Richardson, Bruce <bruce.richard...@intel.com>;
> Mcnamara, John <john.mcnam...@intel.com>
> Cc: Maxime Coquelin <maxime.coque...@redhat.com>
> Subject: [PATCH v2 04/15] vhost: simplify async IO vectors iterators
>
> This patch splits the iterator arrays in two, one for
> source and one for destination. The goal is make the code
> easier to understand.
>
> Signed-off-by: Maxime Coquelin <maxime.coque...@redhat.com>
> ---
> lib/vhost/vhost.h | 5 +++--
> lib/vhost/virtio_net.c | 24 ++++++++++++------------
> 2 files changed, 15 insertions(+), 14 deletions(-)
>
> diff --git a/lib/vhost/vhost.h b/lib/vhost/vhost.h
> index 686f468eff..132c1b070e 100644
> --- a/lib/vhost/vhost.h
> +++ b/lib/vhost/vhost.h
> @@ -48,7 +48,7 @@
>
> #define MAX_PKT_BURST 32
>
> -#define VHOST_MAX_ASYNC_IT (MAX_PKT_BURST * 2)
> +#define VHOST_MAX_ASYNC_IT (MAX_PKT_BURST)
> #define VHOST_MAX_ASYNC_VEC (BUF_VECTOR_MAX * 2)
>
> #define PACKED_DESC_ENQUEUE_USED_FLAG(w) \
> @@ -132,7 +132,8 @@ struct vhost_async {
> /* operation callbacks for DMA */
> struct rte_vhost_async_channel_ops ops;
>
> - struct rte_vhost_iov_iter it_pool[VHOST_MAX_ASYNC_IT];
> + struct rte_vhost_iov_iter src_iov_iter[VHOST_MAX_ASYNC_IT];
> + struct rte_vhost_iov_iter dst_iov_iter[VHOST_MAX_ASYNC_IT];
> struct iovec src_iovec[VHOST_MAX_ASYNC_VEC];
> struct iovec dst_iovec[VHOST_MAX_ASYNC_VEC];
>
> diff --git a/lib/vhost/virtio_net.c b/lib/vhost/virtio_net.c
> index 2a243701c0..f0d923704a 100644
> --- a/lib/vhost/virtio_net.c
> +++ b/lib/vhost/virtio_net.c
> @@ -1511,7 +1511,8 @@ virtio_dev_rx_async_submit_split(struct virtio_net *dev,
> uint16_t avail_head;
>
> struct vhost_async *async = vq->async;
> - struct rte_vhost_iov_iter *it_pool = async->it_pool;
> + struct rte_vhost_iov_iter *src_iter = async->src_iov_iter;
> + struct rte_vhost_iov_iter *dst_iter = async->dst_iov_iter;
> struct rte_vhost_async_desc tdes[MAX_PKT_BURST];
> struct iovec *src_iovec = async->src_iovec;
> struct iovec *dst_iovec = async->dst_iovec;
> @@ -1547,20 +1548,19 @@ virtio_dev_rx_async_submit_split(struct virtio_net
> *dev,
>
> if (async_mbuf_to_desc(dev, vq, pkts[pkt_idx], buf_vec, nr_vec,
> num_buffers,
> &src_iovec[iovec_idx], &dst_iovec[iovec_idx],
> - &it_pool[it_idx], &it_pool[it_idx + 1]) < 0) {
> + &src_iter[it_idx], &dst_iter[it_idx]) < 0) {
> vq->shadow_used_idx -= num_buffers;
> break;
> }
>
> - async_fill_desc(&tdes[pkt_burst_idx++], &it_pool[it_idx],
> - &it_pool[it_idx + 1]);
> + async_fill_desc(&tdes[pkt_burst_idx++], &src_iter[it_idx],
> &dst_iter[it_idx]);
>
> slot_idx = (async->pkts_idx + pkt_idx) & (vq->size - 1);
> pkts_info[slot_idx].descs = num_buffers;
> pkts_info[slot_idx].mbuf = pkts[pkt_idx];
>
> - iovec_idx += it_pool[it_idx].nr_segs;
> - it_idx += 2;
> + iovec_idx += src_iter[it_idx].nr_segs;
> + it_idx++;
>
> vq->last_avail_idx += num_buffers;
>
> @@ -1829,7 +1829,8 @@ virtio_dev_rx_async_submit_packed(struct virtio_net
> *dev,
> uint16_t num_descs;
>
> struct vhost_async *async = vq->async;
> - struct rte_vhost_iov_iter *it_pool = async->it_pool;
> + struct rte_vhost_iov_iter *src_iter = async->src_iov_iter;
> + struct rte_vhost_iov_iter *dst_iter = async->dst_iov_iter;
> struct rte_vhost_async_desc tdes[MAX_PKT_BURST];
> struct iovec *src_iovec = async->src_iovec;
> struct iovec *dst_iovec = async->dst_iovec;
> @@ -1846,18 +1847,17 @@ virtio_dev_rx_async_submit_packed(struct virtio_net
> *dev,
> if (unlikely(virtio_dev_rx_async_packed(dev, vq, pkts[pkt_idx],
> &num_descs, &num_buffers,
> &src_iovec[iovec_idx],
> &dst_iovec[iovec_idx],
> - &it_pool[it_idx],
> &it_pool[it_idx + 1]) <
> 0))
> + &src_iter[it_idx],
> &dst_iter[it_idx]) < 0))
> break;
>
> slot_idx = (async->pkts_idx + pkt_idx) % vq->size;
>
> - async_fill_desc(&tdes[pkt_burst_idx++], &it_pool[it_idx],
> - &it_pool[it_idx + 1]);
> + async_fill_desc(&tdes[pkt_burst_idx++], &src_iter[it_idx],
> &dst_iter[it_idx]);
> pkts_info[slot_idx].descs = num_descs;
> pkts_info[slot_idx].nr_buffers = num_buffers;
> pkts_info[slot_idx].mbuf = pkts[pkt_idx];
> - iovec_idx += it_pool[it_idx].nr_segs;
> - it_idx += 2;
> + iovec_idx += src_iter[it_idx].nr_segs;
> + it_idx++;
>
> pkt_idx++;
> remained--;
> --
> 2.31.1
Reviewed-by: Chenbo Xia <chenbo....@intel.com>
