> On Jan 16, 2025, at 17:54, Maxime Coquelin <maxime.coque...@redhat.com> wrote:
>
> External email: Use caution opening links or attachments
>
>
> This patch refactors the error handling in the Vhost
> dequeue paths to ease its maintenance and readability.
>
> Suggested-by: David Marchand <david.march...@redhat.com>
> Signed-off-by: Maxime Coquelin <maxime.coque...@redhat.com>
> ---
> lib/vhost/virtio_net.c | 58 +++++++++++++++++++-----------------------
> 1 file changed, 26 insertions(+), 32 deletions(-)
>
> diff --git a/lib/vhost/virtio_net.c b/lib/vhost/virtio_net.c
> index a340e5a772..59ea2d16a5 100644
> --- a/lib/vhost/virtio_net.c
> +++ b/lib/vhost/virtio_net.c
> @@ -3593,6 +3593,7 @@ rte_vhost_dequeue_burst(int vid, uint16_t queue_id,
> struct rte_mbuf *rarp_mbuf = NULL;
> struct vhost_virtqueue *vq;
> int16_t success = 1;
> + uint16_t nb_rx = 0;
>
> dev = get_device(vid);
> if (!dev)
> @@ -3602,25 +3603,23 @@ rte_vhost_dequeue_burst(int vid, uint16_t queue_id,
> VHOST_DATA_LOG(dev->ifname, ERR,
> "%s: built-in vhost net backend is disabled.",
> __func__);
> - return 0;
> + goto out_no_unlock;
> }
>
> if (unlikely(!is_valid_virt_queue_idx(queue_id, 1, dev->nr_vring))) {
> VHOST_DATA_LOG(dev->ifname, ERR,
> "%s: invalid virtqueue idx %d.",
> __func__, queue_id);
> - return 0;
> + goto out_no_unlock;
> }
>
> vq = dev->virtqueue[queue_id];
>
> if (unlikely(rte_rwlock_read_trylock(&vq->access_lock) != 0))
> - return 0;
> + goto out_no_unlock;
>
> - if (unlikely(!vq->enabled)) {
> - count = 0;
> + if (unlikely(!vq->enabled))
> goto out_access_unlock;
> - }
>
> vhost_user_iotlb_rd_lock(vq);
>
> @@ -3630,7 +3629,6 @@ rte_vhost_dequeue_burst(int vid, uint16_t queue_id,
>
> virtio_dev_vring_translate(dev, vq);
>
> - count = 0;
> goto out_no_unlock;
> }
>
> @@ -3657,7 +3655,6 @@ rte_vhost_dequeue_burst(int vid, uint16_t queue_id,
> rarp_mbuf = rte_net_make_rarp_packet(mbuf_pool, &dev->mac);
> if (rarp_mbuf == NULL) {
> VHOST_DATA_LOG(dev->ifname, ERR, "failed to make RARP
> packet.");
> - count = 0;
> goto out;
> }
> /*
> @@ -3672,17 +3669,17 @@ rte_vhost_dequeue_burst(int vid, uint16_t queue_id,
>
> if (vq_is_packed(dev)) {
> if (dev->flags & VIRTIO_DEV_LEGACY_OL_FLAGS)
> - count = virtio_dev_tx_packed_legacy(dev, vq,
> mbuf_pool, pkts, count);
> + nb_rx = virtio_dev_tx_packed_legacy(dev, vq,
> mbuf_pool, pkts, count);
> else
> - count = virtio_dev_tx_packed_compliant(dev, vq,
> mbuf_pool, pkts, count);
> + nb_rx = virtio_dev_tx_packed_compliant(dev, vq,
> mbuf_pool, pkts, count);
> } else {
> if (dev->flags & VIRTIO_DEV_LEGACY_OL_FLAGS)
> - count = virtio_dev_tx_split_legacy(dev, vq,
> mbuf_pool, pkts, count);
> + nb_rx = virtio_dev_tx_split_legacy(dev, vq,
> mbuf_pool, pkts, count);
> else
> - count = virtio_dev_tx_split_compliant(dev, vq,
> mbuf_pool, pkts, count);
> + nb_rx = virtio_dev_tx_split_compliant(dev, vq,
> mbuf_pool, pkts, count);
> }
>
> - vhost_queue_stats_update(dev, vq, pkts, count);
> + vhost_queue_stats_update(dev, vq, pkts, nb_rx);
>
> out:
> vhost_user_iotlb_rd_unlock(vq);
> @@ -3691,10 +3688,10 @@ rte_vhost_dequeue_burst(int vid, uint16_t queue_id,
> rte_rwlock_read_unlock(&vq->access_lock);
>
> if (unlikely(rarp_mbuf != NULL))
> - count += 1;
> + nb_rx += 1;
>
> out_no_unlock:
> - return count;
> + return nb_rx;
> }
>
> static __rte_always_inline uint16_t
> @@ -4200,52 +4197,51 @@ rte_vhost_async_try_dequeue_burst(int vid, uint16_t
> queue_id,
> struct rte_mbuf *rarp_mbuf = NULL;
> struct vhost_virtqueue *vq;
> int16_t success = 1;
> + uint16_t nb_rx = 0;
>
> dev = get_device(vid);
> if (!dev || !nr_inflight)
> - return 0;
> + goto out_no_unlock;
>
> *nr_inflight = -1;
>
> if (unlikely(!(dev->flags & VIRTIO_DEV_BUILTIN_VIRTIO_NET))) {
> VHOST_DATA_LOG(dev->ifname, ERR, "%s: built-in vhost net
> backend is disabled.",
> __func__);
> - return 0;
> + goto out_no_unlock;
> }
>
> if (unlikely(!is_valid_virt_queue_idx(queue_id, 1, dev->nr_vring))) {
> VHOST_DATA_LOG(dev->ifname, ERR, "%s: invalid virtqueue idx
> %d.",
> __func__, queue_id);
> - return 0;
> + goto out_no_unlock;
> }
>
> if (unlikely(dma_id < 0 || dma_id >= RTE_DMADEV_DEFAULT_MAX)) {
> VHOST_DATA_LOG(dev->ifname, ERR, "%s: invalid dma id %d.",
> __func__, dma_id);
> - return 0;
> + goto out_no_unlock;
> }
>
> if (unlikely(!dma_copy_track[dma_id].vchans ||
>
> !dma_copy_track[dma_id].vchans[vchan_id].pkts_cmpl_flag_addr)) {
> VHOST_DATA_LOG(dev->ifname, ERR, "%s: invalid channel %d:%u.",
> __func__, dma_id, vchan_id);
> - return 0;
> + goto out_no_unlock;
> }
>
> vq = dev->virtqueue[queue_id];
>
> if (unlikely(rte_rwlock_read_trylock(&vq->access_lock) != 0))
> - return 0;
> + goto out_no_unlock;
>
> if (unlikely(vq->enabled == 0)) {
> - count = 0;
> goto out_access_unlock;
> }
>
> if (unlikely(!vq->async)) {
> VHOST_DATA_LOG(dev->ifname, ERR, "%s: async not registered for
> queue id %d.",
> __func__, queue_id);
> - count = 0;
> goto out_access_unlock;
> }
>
> @@ -4256,7 +4252,6 @@ rte_vhost_async_try_dequeue_burst(int vid, uint16_t
> queue_id,
> rte_rwlock_read_unlock(&vq->access_lock);
>
> virtio_dev_vring_translate(dev, vq);
> - count = 0;
> goto out_no_unlock;
> }
>
> @@ -4283,7 +4278,6 @@ rte_vhost_async_try_dequeue_burst(int vid, uint16_t
> queue_id,
> rarp_mbuf = rte_net_make_rarp_packet(mbuf_pool, &dev->mac);
> if (rarp_mbuf == NULL) {
> VHOST_DATA_LOG(dev->ifname, ERR, "failed to make RARP
> packet.");
> - count = 0;
> goto out;
> }
> /*
> @@ -4298,22 +4292,22 @@ rte_vhost_async_try_dequeue_burst(int vid, uint16_t
> queue_id,
>
> if (vq_is_packed(dev)) {
> if (dev->flags & VIRTIO_DEV_LEGACY_OL_FLAGS)
> - count = virtio_dev_tx_async_packed_legacy(dev, vq,
> mbuf_pool,
> + nb_rx = virtio_dev_tx_async_packed_legacy(dev, vq,
> mbuf_pool,
> pkts, count, dma_id, vchan_id);
> else
> - count = virtio_dev_tx_async_packed_compliant(dev, vq,
> mbuf_pool,
> + nb_rx = virtio_dev_tx_async_packed_compliant(dev, vq,
> mbuf_pool,
> pkts, count, dma_id, vchan_id);
> } else {
> if (dev->flags & VIRTIO_DEV_LEGACY_OL_FLAGS)
> - count = virtio_dev_tx_async_split_legacy(dev, vq,
> mbuf_pool,
> + nb_rx = virtio_dev_tx_async_split_legacy(dev, vq,
> mbuf_pool,
> pkts, count, dma_id, vchan_id);
> else
> - count = virtio_dev_tx_async_split_compliant(dev, vq,
> mbuf_pool,
> + nb_rx = virtio_dev_tx_async_split_compliant(dev, vq,
> mbuf_pool,
> pkts, count, dma_id, vchan_id);
> }
>
> *nr_inflight = vq->async->pkts_inflight_n;
> - vhost_queue_stats_update(dev, vq, pkts, count);
> + vhost_queue_stats_update(dev, vq, pkts, nb_rx);
>
> out:
> vhost_user_iotlb_rd_unlock(vq);
> @@ -4322,8 +4316,8 @@ rte_vhost_async_try_dequeue_burst(int vid, uint16_t
> queue_id,
> rte_rwlock_read_unlock(&vq->access_lock);
>
> if (unlikely(rarp_mbuf != NULL))
> - count += 1;
> + nb_rx += 1;
>
> out_no_unlock:
> - return count;
> + return nb_rx;
> }
> --
> 2.47.1
>
Reviewed-by: Chenbo Xia <chen...@nvidia.com>
