On Thu, Nov 09, 2023 at 07:11:46PM +0800, Xuan Zhuo wrote: > On Thu, 9 Nov 2023 03:12:27 -0500, "Michael S. Tsirkin" <mst@xxxxxxxxxx> wrote: > > On Tue, Nov 07, 2023 at 11:12:22AM +0800, Xuan Zhuo wrote: > > > Implement the logic of filling rq with XSK buffers. > > > > > > Signed-off-by: Xuan Zhuo <xuanzhuo@xxxxxxxxxxxxxxxxx> > > > --- > > > drivers/net/virtio/main.c | 4 ++- > > > drivers/net/virtio/virtio_net.h | 5 ++++ > > > drivers/net/virtio/xsk.c | 49 ++++++++++++++++++++++++++++++++- > > > drivers/net/virtio/xsk.h | 2 ++ > > > 4 files changed, 58 insertions(+), 2 deletions(-) > > > > > > diff --git a/drivers/net/virtio/main.c b/drivers/net/virtio/main.c > > > index 6210a6e37396..15943a22e17d 100644 > > > --- a/drivers/net/virtio/main.c > > > +++ b/drivers/net/virtio/main.c > > > @@ -1798,7 +1798,9 @@ static bool try_fill_recv(struct virtnet_info *vi, struct virtnet_rq *rq, > > > bool oom; > > > > > > do { > > > - if (vi->mergeable_rx_bufs) > > > + if (rq->xsk.pool) > > > + err = virtnet_add_recvbuf_xsk(vi, rq, rq->xsk.pool, gfp); > > > + else if (vi->mergeable_rx_bufs) > > > err = add_recvbuf_mergeable(vi, rq, gfp); > > > else if (vi->big_packets) > > > err = add_recvbuf_big(vi, rq, gfp); > > > > I'm not sure I understand. How does this handle mergeable flag still being set? > > > You has the same question as Jason. > > So I think maybe I should put the handle into the > add_recvbuf_mergeable and add_recvbuf_small. > > Let me think about this. > > > > > > > > > diff --git a/drivers/net/virtio/virtio_net.h b/drivers/net/virtio/virtio_net.h > > > index a13d6d301fdb..1242785e311e 100644 > > > --- a/drivers/net/virtio/virtio_net.h > > > +++ b/drivers/net/virtio/virtio_net.h > > > @@ -140,6 +140,11 @@ struct virtnet_rq { > > > > > > /* xdp rxq used by xsk */ > > > struct xdp_rxq_info xdp_rxq; > > > + > > > + struct xdp_buff **xsk_buffs; > > > + u32 nxt_idx; > > > + u32 num; > > > + u32 size; > > > } xsk; > > > }; > > > > > > diff --git a/drivers/net/virtio/xsk.c b/drivers/net/virtio/xsk.c > > > index ea5804ddd44e..e737c3353212 100644 > > > --- a/drivers/net/virtio/xsk.c > > > +++ b/drivers/net/virtio/xsk.c > > > @@ -38,6 +38,41 @@ static void virtnet_xsk_check_queue(struct virtnet_sq *sq) > > > netif_stop_subqueue(dev, qnum); > > > } > > > > > > +int virtnet_add_recvbuf_xsk(struct virtnet_info *vi, struct virtnet_rq *rq, > > > + struct xsk_buff_pool *pool, gfp_t gfp) > > > +{ > > > + struct xdp_buff **xsk_buffs; > > > + dma_addr_t addr; > > > + u32 len, i; > > > + int err = 0; > > > + > > > + xsk_buffs = rq->xsk.xsk_buffs; > > > + > > > + if (rq->xsk.nxt_idx >= rq->xsk.num) { > > > + rq->xsk.num = xsk_buff_alloc_batch(pool, xsk_buffs, rq->xsk.size); > > > + if (!rq->xsk.num) > > > + return -ENOMEM; > > > + rq->xsk.nxt_idx = 0; > > > + } > > > > Another manually rolled linked list implementation. > > Please, don't. > > > The array is for speedup. > > xsk_buff_alloc_batch will return many xsk_buff that will be more efficient than > the xsk_buff_alloc. But your sg list just contains a single entry? I think that you have to walk through the xsk_buffs array, retrieve dma addrs from there and have sg list sized to the value xsk_buff_alloc_batch() returned. I don't think your logic based on nxt_idx is needed. Please take a look how other drivers use xsk_buff_alloc_batch(). I don't see callsites of virtnet_add_recvbuf_xsk() though. > > Thanks. > > > > > > > > + > > > + i = rq->xsk.nxt_idx; > > > + > > > + /* use the part of XDP_PACKET_HEADROOM as the virtnet hdr space */ > > > + addr = xsk_buff_xdp_get_dma(xsk_buffs[i]) - vi->hdr_len; > > > + len = xsk_pool_get_rx_frame_size(pool) + vi->hdr_len; > > > + > > > + sg_init_table(rq->sg, 1); > > > + sg_fill_dma(rq->sg, addr, len); > > > + > > > + err = virtqueue_add_inbuf(rq->vq, rq->sg, 1, xsk_buffs[i], gfp); > > > + if (err) > > > + return err; > > > + > > > + rq->xsk.nxt_idx++; > > > + > > > + return 0; > > > +} > > > + > > > static int virtnet_xsk_xmit_one(struct virtnet_sq *sq, > > > struct xsk_buff_pool *pool, > > > struct xdp_desc *desc) > > > @@ -213,7 +248,7 @@ static int virtnet_xsk_pool_enable(struct net_device *dev, > > > struct virtnet_sq *sq; > > > struct device *dma_dev; > > > dma_addr_t hdr_dma; > > > - int err; > > > + int err, size; > > > > > > /* In big_packets mode, xdp cannot work, so there is no need to > > > * initialize xsk of rq. > > > @@ -249,6 +284,16 @@ static int virtnet_xsk_pool_enable(struct net_device *dev, > > > if (!dma_dev) > > > return -EPERM; > > > > > > + size = virtqueue_get_vring_size(rq->vq); > > > + > > > + rq->xsk.xsk_buffs = kcalloc(size, sizeof(*rq->xsk.xsk_buffs), GFP_KERNEL); > > > + if (!rq->xsk.xsk_buffs) > > > + return -ENOMEM; > > > + > > > + rq->xsk.size = size; > > > + rq->xsk.nxt_idx = 0; > > > + rq->xsk.num = 0; > > > + > > > hdr_dma = dma_map_single(dma_dev, &xsk_hdr, vi->hdr_len, DMA_TO_DEVICE); > > > if (dma_mapping_error(dma_dev, hdr_dma)) > > > return -ENOMEM; > > > @@ -307,6 +352,8 @@ static int virtnet_xsk_pool_disable(struct net_device *dev, u16 qid) > > > > > > dma_unmap_single(dma_dev, sq->xsk.hdr_dma_address, vi->hdr_len, DMA_TO_DEVICE); > > > > > > + kfree(rq->xsk.xsk_buffs); > > > + > > > return err1 | err2; > > > } > > > > > > diff --git a/drivers/net/virtio/xsk.h b/drivers/net/virtio/xsk.h > > > index 7ebc9bda7aee..bef41a3f954e 100644 > > > --- a/drivers/net/virtio/xsk.h > > > +++ b/drivers/net/virtio/xsk.h > > > @@ -23,4 +23,6 @@ int virtnet_xsk_pool_setup(struct net_device *dev, struct netdev_bpf *xdp); > > > bool virtnet_xsk_xmit(struct virtnet_sq *sq, struct xsk_buff_pool *pool, > > > int budget); > > > int virtnet_xsk_wakeup(struct net_device *dev, u32 qid, u32 flag); > > > +int virtnet_add_recvbuf_xsk(struct virtnet_info *vi, struct virtnet_rq *rq, > > > + struct xsk_buff_pool *pool, gfp_t gfp); > > > #endif > > > -- > > > 2.32.0.3.g01195cf9f > > > > >