From 97064162d47001c50f0aabad3cc365f7d0ce43c9 Mon Sep 17 00:00:00 2001 From: Maxime Coquelin Date: Tue, 26 Oct 2021 18:28:52 +0200 Subject: [PATCH] vhost: simplify async IO vectors IO vectors implementation is unnecessarily complex, mixing source and destinations vectors in the same array. This patch declares two arrays, one for the source and one for the destination. It also gets rid of seg_awaits variable in both packed and split implementation, which is the same as iovec_idx. Signed-off-by: Maxime Coquelin Reviewed-by: Chenbo Xia Reviewed-by: Jiayu Hu --- lib/vhost/vhost.h | 5 +++-- lib/vhost/virtio_net.c | 28 +++++++++++----------------- 2 files changed, 14 insertions(+), 19 deletions(-) diff --git a/lib/vhost/vhost.h b/lib/vhost/vhost.h index fa92a0d33d..b0bad495e1 100644 --- a/lib/vhost/vhost.h +++ b/lib/vhost/vhost.h @@ -49,7 +49,7 @@ #define MAX_PKT_BURST 32 #define VHOST_MAX_ASYNC_IT (MAX_PKT_BURST * 2) -#define VHOST_MAX_ASYNC_VEC (BUF_VECTOR_MAX * 4) +#define VHOST_MAX_ASYNC_VEC (BUF_VECTOR_MAX * 2) #define PACKED_DESC_ENQUEUE_USED_FLAG(w) \ ((w) ? (VRING_DESC_F_AVAIL | VRING_DESC_F_USED | VRING_DESC_F_WRITE) : \ @@ -133,7 +133,8 @@ struct vhost_async { struct rte_vhost_async_channel_ops ops; struct rte_vhost_iov_iter it_pool[VHOST_MAX_ASYNC_IT]; - struct iovec vec_pool[VHOST_MAX_ASYNC_VEC]; + struct iovec src_iovec[VHOST_MAX_ASYNC_VEC]; + struct iovec dst_iovec[VHOST_MAX_ASYNC_VEC]; /* data transfer status */ struct async_inflight_info *pkts_info; diff --git a/lib/vhost/virtio_net.c b/lib/vhost/virtio_net.c index d9ac85f829..2a243701c0 100644 --- a/lib/vhost/virtio_net.c +++ b/lib/vhost/virtio_net.c @@ -1512,14 +1512,12 @@ virtio_dev_rx_async_submit_split(struct virtio_net *dev, struct vhost_async *async = vq->async; struct rte_vhost_iov_iter *it_pool = async->it_pool; - struct iovec *vec_pool = async->vec_pool; struct rte_vhost_async_desc tdes[MAX_PKT_BURST]; - struct iovec *src_iovec = vec_pool; - struct iovec *dst_iovec = vec_pool + (VHOST_MAX_ASYNC_VEC >> 1); + struct iovec *src_iovec = async->src_iovec; + struct iovec *dst_iovec = async->dst_iovec; struct async_inflight_info *pkts_info = async->pkts_info; uint32_t n_pkts = 0, pkt_err = 0; int32_t n_xfer; - uint16_t segs_await = 0; uint16_t iovec_idx = 0, it_idx = 0, slot_idx = 0; /* @@ -1562,7 +1560,6 @@ virtio_dev_rx_async_submit_split(struct virtio_net *dev, pkts_info[slot_idx].mbuf = pkts[pkt_idx]; iovec_idx += it_pool[it_idx].nr_segs; - segs_await += it_pool[it_idx].nr_segs; it_idx += 2; vq->last_avail_idx += num_buffers; @@ -1573,8 +1570,7 @@ virtio_dev_rx_async_submit_split(struct virtio_net *dev, * - unused async iov number is less than max vhost vector */ if (unlikely(pkt_burst_idx >= VHOST_ASYNC_BATCH_THRESHOLD || - ((VHOST_MAX_ASYNC_VEC >> 1) - segs_await < - BUF_VECTOR_MAX))) { + (VHOST_MAX_ASYNC_VEC - iovec_idx < BUF_VECTOR_MAX))) { n_xfer = async->ops.transfer_data(dev->vid, queue_id, tdes, 0, pkt_burst_idx); if (likely(n_xfer >= 0)) { @@ -1588,7 +1584,6 @@ virtio_dev_rx_async_submit_split(struct virtio_net *dev, iovec_idx = 0; it_idx = 0; - segs_await = 0; if (unlikely(n_pkts < pkt_burst_idx)) { /* @@ -1745,8 +1740,11 @@ vhost_enqueue_async_packed(struct virtio_net *dev, if (unlikely(++tries > max_tries)) return -1; - if (unlikely(fill_vec_buf_packed(dev, vq, avail_idx, &desc_count, buf_vec, &nr_vec, - &buf_id, &len, VHOST_ACCESS_RW) < 0)) + if (unlikely(fill_vec_buf_packed(dev, vq, + avail_idx, &desc_count, + buf_vec, &nr_vec, + &buf_id, &len, + VHOST_ACCESS_RW) < 0)) return -1; len = RTE_MIN(len, size); @@ -1832,14 +1830,12 @@ virtio_dev_rx_async_submit_packed(struct virtio_net *dev, struct vhost_async *async = vq->async; struct rte_vhost_iov_iter *it_pool = async->it_pool; - struct iovec *vec_pool = async->vec_pool; struct rte_vhost_async_desc tdes[MAX_PKT_BURST]; - struct iovec *src_iovec = vec_pool; - struct iovec *dst_iovec = vec_pool + (VHOST_MAX_ASYNC_VEC >> 1); + struct iovec *src_iovec = async->src_iovec; + struct iovec *dst_iovec = async->dst_iovec; struct async_inflight_info *pkts_info = async->pkts_info; uint32_t n_pkts = 0, pkt_err = 0; uint16_t slot_idx = 0; - uint16_t segs_await = 0; uint16_t iovec_idx = 0, it_idx = 0; do { @@ -1861,7 +1857,6 @@ virtio_dev_rx_async_submit_packed(struct virtio_net *dev, pkts_info[slot_idx].nr_buffers = num_buffers; pkts_info[slot_idx].mbuf = pkts[pkt_idx]; iovec_idx += it_pool[it_idx].nr_segs; - segs_await += it_pool[it_idx].nr_segs; it_idx += 2; pkt_idx++; @@ -1874,7 +1869,7 @@ virtio_dev_rx_async_submit_packed(struct virtio_net *dev, * - unused async iov number is less than max vhost vector */ if (unlikely(pkt_burst_idx >= VHOST_ASYNC_BATCH_THRESHOLD || - ((VHOST_MAX_ASYNC_VEC >> 1) - segs_await < BUF_VECTOR_MAX))) { + (VHOST_MAX_ASYNC_VEC - iovec_idx < BUF_VECTOR_MAX))) { n_xfer = async->ops.transfer_data(dev->vid, queue_id, tdes, 0, pkt_burst_idx); if (likely(n_xfer >= 0)) { @@ -1888,7 +1883,6 @@ virtio_dev_rx_async_submit_packed(struct virtio_net *dev, iovec_idx = 0; it_idx = 0; - segs_await = 0; if (unlikely(n_pkts < pkt_burst_idx)) { /* -- 2.39.5