> -----Original Message----- > From: Jiang, Cheng1 <[email protected]> > Sent: Tuesday, October 11, 2022 11:08 AM > To: [email protected]; Xia, Chenbo <[email protected]> > Cc: [email protected]; Hu, Jiayu <[email protected]>; Ding, Xuan > <[email protected]>; Ma, WenwuX <[email protected]>; Wang, YuanX > <[email protected]>; Yang, YvonneX <[email protected]>; He, > Xingguang <[email protected]>; Jiang, Cheng1 <[email protected]>; > [email protected] > Subject: [PATCH v2 2/2] vhost: fix slot index calculation in async vhost > > When the packet receiving failure and the DMA ring full occur > simultaneously in the asynchronous vhost, the slot_idx needs to be > decreased by 1. For packed virtqueue, the slot index should be > ring_size - 1, if the slot_idx is currently 0, since the ring size is > not necessarily the power of 2. > > Fixes: 84d5204310d7 ("vhost: support async dequeue for split ring") > Fixes: fe8477ebbd94 ("vhost: support async packed ring dequeue") > Cc: [email protected] > > Signed-off-by: Cheng Jiang <[email protected]> > --- > lib/vhost/virtio_net.c | 16 ++++++++++++++-- > 1 file changed, 14 insertions(+), 2 deletions(-) > > diff --git a/lib/vhost/virtio_net.c b/lib/vhost/virtio_net.c > index 457ac2e92a..efebd063d7 100644 > --- a/lib/vhost/virtio_net.c > +++ b/lib/vhost/virtio_net.c > @@ -3457,6 +3457,7 @@ virtio_dev_tx_async_split(struct virtio_net *dev, > struct vhost_virtqueue *vq, > allocerr_warned = true; > } > dropped = true; > + slot_idx--; > break; > } > > @@ -3647,6 +3648,12 @@ virtio_dev_tx_async_packed(struct virtio_net *dev, > struct vhost_virtqueue *vq, > if (unlikely(virtio_dev_tx_async_single_packed(dev, vq, > mbuf_pool, pkt, > slot_idx, legacy_ol_flags))) { > rte_pktmbuf_free_bulk(&pkts_prealloc[pkt_idx], count - > pkt_idx); > + > + if (slot_idx == 0) > + slot_idx = vq->size - 1; > + else > + slot_idx--; > + > break; > } > > @@ -3674,8 +3681,13 @@ virtio_dev_tx_async_packed(struct virtio_net *dev, > struct vhost_virtqueue *vq, > async->buffer_idx_packed += vq->size - pkt_err; > > while (pkt_err-- > 0) { > - rte_pktmbuf_free(pkts_info[slot_idx % vq->size].mbuf); > - slot_idx--; > + rte_pktmbuf_free(pkts_info[slot_idx].mbuf); > + descs_err += pkts_info[slot_idx].descs; > + > + if (slot_idx == 0) > + slot_idx = vq->size - 1; > + else > + slot_idx--; > } > > /* recover available ring */ > -- > 2.35.1
Reviewed-by: Chenbo Xia <[email protected]>
