| Message ID | 20231107031227.100015-19-xuanzhuo@linux.alibaba.com (mailing list archive) |
|---|---|
| State | Deferred |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | virtio-net: support AF_XDP zero copy | expand |
| Context | Check | Description |
|---|---|---|
| netdev/tree_selection | success | Clearly marked for net-next, async |
| netdev/apply | fail | Patch does not apply to net-next |
On Tue, Nov 07, 2023 at 11:12:24AM +0800, Xuan Zhuo wrote: > The virtnet_xdp_handler() is re-used. But > > 1. We need to copy data to create skb for XDP_PASS. > 2. We need to call xsk_buff_free() to release the buffer. > 3. The handle for xdp_buff is difference. > > If we pushed this logic into existing receive handle(merge and small), > we would have to maintain code scattered inside merge and small (and big). > So I think it is a good choice for us to put the xsk code into an > independent function. > > Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com> > --- > drivers/net/virtio/main.c | 12 ++-- > drivers/net/virtio/virtio_net.h | 4 ++ > drivers/net/virtio/xsk.c | 120 ++++++++++++++++++++++++++++++++ > drivers/net/virtio/xsk.h | 4 ++ > 4 files changed, 135 insertions(+), 5 deletions(-) > > diff --git a/drivers/net/virtio/main.c b/drivers/net/virtio/main.c > index a318b2533b94..095f4acb0577 100644 > --- a/drivers/net/virtio/main.c > +++ b/drivers/net/virtio/main.c > @@ -831,10 +831,10 @@ static void put_xdp_frags(struct xdp_buff *xdp) > } > } > > -static int virtnet_xdp_handler(struct bpf_prog *xdp_prog, struct xdp_buff *xdp, > - struct net_device *dev, > - unsigned int *xdp_xmit, > - struct virtnet_rq_stats *stats) > +int virtnet_xdp_handler(struct bpf_prog *xdp_prog, struct xdp_buff *xdp, > + struct net_device *dev, > + unsigned int *xdp_xmit, > + struct virtnet_rq_stats *stats) > { > struct xdp_frame *xdpf; > int err; > @@ -1598,7 +1598,9 @@ static void receive_buf(struct virtnet_info *vi, struct virtnet_rq *rq, > return; > } > > - if (vi->mergeable_rx_bufs) > + if (rq->xsk.pool) > + skb = virtnet_receive_xsk(dev, vi, rq, buf, len, xdp_xmit, stats); > + else if (vi->mergeable_rx_bufs) > skb = receive_mergeable(dev, vi, rq, buf, ctx, len, xdp_xmit, > stats); > else if (vi->big_packets) > diff --git a/drivers/net/virtio/virtio_net.h b/drivers/net/virtio/virtio_net.h > index 2005d0cd22e2..f520fec06662 100644 > --- a/drivers/net/virtio/virtio_net.h > +++ b/drivers/net/virtio/virtio_net.h > @@ -339,4 +339,8 @@ void virtnet_tx_pause(struct virtnet_info *vi, struct virtnet_sq *sq); > void virtnet_tx_resume(struct virtnet_info *vi, struct virtnet_sq *sq); > void virtnet_sq_free_unused_buf(struct virtqueue *vq, void *buf); > void virtnet_rq_free_unused_buf(struct virtqueue *vq, void *buf); > +int virtnet_xdp_handler(struct bpf_prog *xdp_prog, struct xdp_buff *xdp, > + struct net_device *dev, > + unsigned int *xdp_xmit, > + struct virtnet_rq_stats *stats); > #endif > diff --git a/drivers/net/virtio/xsk.c b/drivers/net/virtio/xsk.c > index b09c473c29fb..5c7eb19ab04b 100644 > --- a/drivers/net/virtio/xsk.c > +++ b/drivers/net/virtio/xsk.c > @@ -14,6 +14,18 @@ static void sg_fill_dma(struct scatterlist *sg, dma_addr_t addr, u32 len) > sg->length = len; > } > > +static unsigned int virtnet_receive_buf_num(struct virtnet_info *vi, char *buf) > +{ > + struct virtio_net_hdr_mrg_rxbuf *hdr; > + > + if (vi->mergeable_rx_bufs) { > + hdr = (struct virtio_net_hdr_mrg_rxbuf *)buf; > + return virtio16_to_cpu(vi->vdev, hdr->num_buffers); > + } > + > + return 1; > +} > + > static void virtnet_xsk_check_queue(struct virtnet_sq *sq) > { > struct virtnet_info *vi = sq->vq->vdev->priv; > @@ -38,6 +50,114 @@ static void virtnet_xsk_check_queue(struct virtnet_sq *sq) > netif_stop_subqueue(dev, qnum); > } > > +static void merge_drop_follow_xdp(struct net_device *dev, > + struct virtnet_rq *rq, > + u32 num_buf, > + struct virtnet_rq_stats *stats) > +{ > + struct xdp_buff *xdp; > + u32 len; > + > + while (num_buf-- > 1) { > + xdp = virtqueue_get_buf(rq->vq, &len); > + if (unlikely(!xdp)) { > + pr_debug("%s: rx error: %d buffers missing\n", > + dev->name, num_buf); > + dev->stats.rx_length_errors++; > + break; > + } > + u64_stats_add(&stats->bytes, len); > + xsk_buff_free(xdp); > + } > +} > + > +static struct sk_buff *construct_skb(struct virtnet_rq *rq, could you name this to virtnet_construct_skb_zc > + struct xdp_buff *xdp) > +{ > + unsigned int metasize = xdp->data - xdp->data_meta; > + struct sk_buff *skb; > + unsigned int size; > + > + size = xdp->data_end - xdp->data_hard_start; > + skb = napi_alloc_skb(&rq->napi, size); > + if (unlikely(!skb)) > + return NULL; > + > + skb_reserve(skb, xdp->data_meta - xdp->data_hard_start); > + > + size = xdp->data_end - xdp->data_meta; > + memcpy(__skb_put(skb, size), xdp->data_meta, size); > + > + if (metasize) { > + __skb_pull(skb, metasize); > + skb_metadata_set(skb, metasize); > + } > + > + return skb; > +} > + > +struct sk_buff *virtnet_receive_xsk(struct net_device *dev, struct virtnet_info *vi, > + struct virtnet_rq *rq, void *buf, > + unsigned int len, unsigned int *xdp_xmit, > + struct virtnet_rq_stats *stats) > +{ > + struct virtio_net_hdr_mrg_rxbuf *hdr; > + struct sk_buff *skb = NULL; > + u32 ret, headroom, num_buf; > + struct bpf_prog *prog; > + struct xdp_buff *xdp; > + > + len -= vi->hdr_len; > + > + xdp = (struct xdp_buff *)buf; > + > + xsk_buff_set_size(xdp, len); > + > + hdr = xdp->data - vi->hdr_len; > + > + num_buf = virtnet_receive_buf_num(vi, (char *)hdr); > + if (num_buf > 1) > + goto drop; > + > + headroom = xdp->data - xdp->data_hard_start; > + > + xdp_prepare_buff(xdp, xdp->data_hard_start, headroom, len, true); Please don't. xsk_buff_pool has ::data_hard_start initialized and you already initialized ::data and ::data_end within xsk_buff_set_size(). > + xsk_buff_dma_sync_for_cpu(xdp, rq->xsk.pool); > + > + ret = XDP_PASS; > + rcu_read_lock(); We don't need RCU sections for running XDP progs anymore. > + prog = rcu_dereference(rq->xdp_prog); > + if (prog) Prog is always !NULL for ZC case. Just dereference it at the beginning of rx processing instead of doing it for each buf. > + ret = virtnet_xdp_handler(prog, xdp, dev, xdp_xmit, stats); > + rcu_read_unlock(); > + > + switch (ret) { > + case XDP_PASS: > + skb = construct_skb(rq, xdp); > + xsk_buff_free(xdp); > + break; > + > + case XDP_TX: > + case XDP_REDIRECT: > + goto consumed; > + > + default: > + goto drop; > + } > + > + return skb; > + > +drop: > + u64_stats_inc(&stats->drops); > + > + xsk_buff_free(xdp); > + > + if (num_buf > 1) > + merge_drop_follow_xdp(dev, rq, num_buf, stats); > +consumed: > + return NULL; > +} > + > int virtnet_add_recvbuf_xsk(struct virtnet_info *vi, struct virtnet_rq *rq, > struct xsk_buff_pool *pool, gfp_t gfp) > { > diff --git a/drivers/net/virtio/xsk.h b/drivers/net/virtio/xsk.h > index bef41a3f954e..dbd2839a5f61 100644 > --- a/drivers/net/virtio/xsk.h > +++ b/drivers/net/virtio/xsk.h > @@ -25,4 +25,8 @@ bool virtnet_xsk_xmit(struct virtnet_sq *sq, struct xsk_buff_pool *pool, > 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); > +struct sk_buff *virtnet_receive_xsk(struct net_device *dev, struct virtnet_info *vi, > + struct virtnet_rq *rq, void *buf, > + unsigned int len, unsigned int *xdp_xmit, > + struct virtnet_rq_stats *stats); > #endif > -- > 2.32.0.3.g01195cf9f > >
On Mon, 13 Nov 2023 17:11:04 +0100, Maciej Fijalkowski <maciej.fijalkowski@intel.com> wrote: > On Tue, Nov 07, 2023 at 11:12:24AM +0800, Xuan Zhuo wrote: > > The virtnet_xdp_handler() is re-used. But > > > > 1. We need to copy data to create skb for XDP_PASS. > > 2. We need to call xsk_buff_free() to release the buffer. > > 3. The handle for xdp_buff is difference. > > > > If we pushed this logic into existing receive handle(merge and small), > > we would have to maintain code scattered inside merge and small (and big). > > So I think it is a good choice for us to put the xsk code into an > > independent function. > > > > Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com> > > --- > > drivers/net/virtio/main.c | 12 ++-- > > drivers/net/virtio/virtio_net.h | 4 ++ > > drivers/net/virtio/xsk.c | 120 ++++++++++++++++++++++++++++++++ > > drivers/net/virtio/xsk.h | 4 ++ > > 4 files changed, 135 insertions(+), 5 deletions(-) > > > > diff --git a/drivers/net/virtio/main.c b/drivers/net/virtio/main.c > > index a318b2533b94..095f4acb0577 100644 > > --- a/drivers/net/virtio/main.c > > +++ b/drivers/net/virtio/main.c > > @@ -831,10 +831,10 @@ static void put_xdp_frags(struct xdp_buff *xdp) > > } > > } > > > > -static int virtnet_xdp_handler(struct bpf_prog *xdp_prog, struct xdp_buff *xdp, > > - struct net_device *dev, > > - unsigned int *xdp_xmit, > > - struct virtnet_rq_stats *stats) > > +int virtnet_xdp_handler(struct bpf_prog *xdp_prog, struct xdp_buff *xdp, > > + struct net_device *dev, > > + unsigned int *xdp_xmit, > > + struct virtnet_rq_stats *stats) > > { > > struct xdp_frame *xdpf; > > int err; > > @@ -1598,7 +1598,9 @@ static void receive_buf(struct virtnet_info *vi, struct virtnet_rq *rq, > > return; > > } > > > > - if (vi->mergeable_rx_bufs) > > + if (rq->xsk.pool) > > + skb = virtnet_receive_xsk(dev, vi, rq, buf, len, xdp_xmit, stats); > > + else if (vi->mergeable_rx_bufs) > > skb = receive_mergeable(dev, vi, rq, buf, ctx, len, xdp_xmit, > > stats); > > else if (vi->big_packets) > > diff --git a/drivers/net/virtio/virtio_net.h b/drivers/net/virtio/virtio_net.h > > index 2005d0cd22e2..f520fec06662 100644 > > --- a/drivers/net/virtio/virtio_net.h > > +++ b/drivers/net/virtio/virtio_net.h > > @@ -339,4 +339,8 @@ void virtnet_tx_pause(struct virtnet_info *vi, struct virtnet_sq *sq); > > void virtnet_tx_resume(struct virtnet_info *vi, struct virtnet_sq *sq); > > void virtnet_sq_free_unused_buf(struct virtqueue *vq, void *buf); > > void virtnet_rq_free_unused_buf(struct virtqueue *vq, void *buf); > > +int virtnet_xdp_handler(struct bpf_prog *xdp_prog, struct xdp_buff *xdp, > > + struct net_device *dev, > > + unsigned int *xdp_xmit, > > + struct virtnet_rq_stats *stats); > > #endif > > diff --git a/drivers/net/virtio/xsk.c b/drivers/net/virtio/xsk.c > > index b09c473c29fb..5c7eb19ab04b 100644 > > --- a/drivers/net/virtio/xsk.c > > +++ b/drivers/net/virtio/xsk.c > > @@ -14,6 +14,18 @@ static void sg_fill_dma(struct scatterlist *sg, dma_addr_t addr, u32 len) > > sg->length = len; > > } > > > > +static unsigned int virtnet_receive_buf_num(struct virtnet_info *vi, char *buf) > > +{ > > + struct virtio_net_hdr_mrg_rxbuf *hdr; > > + > > + if (vi->mergeable_rx_bufs) { > > + hdr = (struct virtio_net_hdr_mrg_rxbuf *)buf; > > + return virtio16_to_cpu(vi->vdev, hdr->num_buffers); > > + } > > + > > + return 1; > > +} > > + > > static void virtnet_xsk_check_queue(struct virtnet_sq *sq) > > { > > struct virtnet_info *vi = sq->vq->vdev->priv; > > @@ -38,6 +50,114 @@ static void virtnet_xsk_check_queue(struct virtnet_sq *sq) > > netif_stop_subqueue(dev, qnum); > > } > > > > +static void merge_drop_follow_xdp(struct net_device *dev, > > + struct virtnet_rq *rq, > > + u32 num_buf, > > + struct virtnet_rq_stats *stats) > > +{ > > + struct xdp_buff *xdp; > > + u32 len; > > + > > + while (num_buf-- > 1) { > > + xdp = virtqueue_get_buf(rq->vq, &len); > > + if (unlikely(!xdp)) { > > + pr_debug("%s: rx error: %d buffers missing\n", > > + dev->name, num_buf); > > + dev->stats.rx_length_errors++; > > + break; > > + } > > + u64_stats_add(&stats->bytes, len); > > + xsk_buff_free(xdp); > > + } > > +} > > + > > +static struct sk_buff *construct_skb(struct virtnet_rq *rq, > > could you name this to virtnet_construct_skb_zc > > > + struct xdp_buff *xdp) > > +{ > > + unsigned int metasize = xdp->data - xdp->data_meta; > > + struct sk_buff *skb; > > + unsigned int size; > > + > > + size = xdp->data_end - xdp->data_hard_start; > > + skb = napi_alloc_skb(&rq->napi, size); > > + if (unlikely(!skb)) > > + return NULL; > > + > > + skb_reserve(skb, xdp->data_meta - xdp->data_hard_start); > > + > > + size = xdp->data_end - xdp->data_meta; > > + memcpy(__skb_put(skb, size), xdp->data_meta, size); > > + > > + if (metasize) { > > + __skb_pull(skb, metasize); > > + skb_metadata_set(skb, metasize); > > + } > > + > > + return skb; > > +} > > + > > +struct sk_buff *virtnet_receive_xsk(struct net_device *dev, struct virtnet_info *vi, > > + struct virtnet_rq *rq, void *buf, > > + unsigned int len, unsigned int *xdp_xmit, > > + struct virtnet_rq_stats *stats) > > +{ > > + struct virtio_net_hdr_mrg_rxbuf *hdr; > > + struct sk_buff *skb = NULL; > > + u32 ret, headroom, num_buf; > > + struct bpf_prog *prog; > > + struct xdp_buff *xdp; > > + > > + len -= vi->hdr_len; > > + > > + xdp = (struct xdp_buff *)buf; > > + > > + xsk_buff_set_size(xdp, len); > > + > > + hdr = xdp->data - vi->hdr_len; > > + > > + num_buf = virtnet_receive_buf_num(vi, (char *)hdr); > > + if (num_buf > 1) > > + goto drop; > > + > > + headroom = xdp->data - xdp->data_hard_start; > > + > > + xdp_prepare_buff(xdp, xdp->data_hard_start, headroom, len, true); > > Please don't. > > xsk_buff_pool has ::data_hard_start initialized and you already > initialized ::data and ::data_end within xsk_buff_set_size(). Yes, you are right. > > > + xsk_buff_dma_sync_for_cpu(xdp, rq->xsk.pool); > > + > > + ret = XDP_PASS; > > + rcu_read_lock(); > > We don't need RCU sections for running XDP progs anymore. > > > + prog = rcu_dereference(rq->xdp_prog); > > + if (prog) > > Prog is always !NULL for ZC case. Just dereference it at the beginning of > rx processing instead of doing it for each buf. That is a problem of virtio-net. I notice that, I will post patch to fix that. Thanks. > > > + ret = virtnet_xdp_handler(prog, xdp, dev, xdp_xmit, stats); > > + rcu_read_unlock(); > > + > > + switch (ret) { > > + case XDP_PASS: > > + skb = construct_skb(rq, xdp); > > + xsk_buff_free(xdp); > > + break; > > + > > + case XDP_TX: > > + case XDP_REDIRECT: > > + goto consumed; > > + > > + default: > > + goto drop; > > + } > > + > > + return skb; > > + > > +drop: > > + u64_stats_inc(&stats->drops); > > + > > + xsk_buff_free(xdp); > > + > > + if (num_buf > 1) > > + merge_drop_follow_xdp(dev, rq, num_buf, stats); > > +consumed: > > + return NULL; > > +} > > + > > int virtnet_add_recvbuf_xsk(struct virtnet_info *vi, struct virtnet_rq *rq, > > struct xsk_buff_pool *pool, gfp_t gfp) > > { > > diff --git a/drivers/net/virtio/xsk.h b/drivers/net/virtio/xsk.h > > index bef41a3f954e..dbd2839a5f61 100644 > > --- a/drivers/net/virtio/xsk.h > > +++ b/drivers/net/virtio/xsk.h > > @@ -25,4 +25,8 @@ bool virtnet_xsk_xmit(struct virtnet_sq *sq, struct xsk_buff_pool *pool, > > 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); > > +struct sk_buff *virtnet_receive_xsk(struct net_device *dev, struct virtnet_info *vi, > > + struct virtnet_rq *rq, void *buf, > > + unsigned int len, unsigned int *xdp_xmit, > > + struct virtnet_rq_stats *stats); > > #endif > > -- > > 2.32.0.3.g01195cf9f > > > >
diff --git a/drivers/net/virtio/main.c b/drivers/net/virtio/main.c index a318b2533b94..095f4acb0577 100644 --- a/drivers/net/virtio/main.c +++ b/drivers/net/virtio/main.c @@ -831,10 +831,10 @@ static void put_xdp_frags(struct xdp_buff *xdp) } } -static int virtnet_xdp_handler(struct bpf_prog *xdp_prog, struct xdp_buff *xdp, - struct net_device *dev, - unsigned int *xdp_xmit, - struct virtnet_rq_stats *stats) +int virtnet_xdp_handler(struct bpf_prog *xdp_prog, struct xdp_buff *xdp, + struct net_device *dev, + unsigned int *xdp_xmit, + struct virtnet_rq_stats *stats) { struct xdp_frame *xdpf; int err; @@ -1598,7 +1598,9 @@ static void receive_buf(struct virtnet_info *vi, struct virtnet_rq *rq, return; } - if (vi->mergeable_rx_bufs) + if (rq->xsk.pool) + skb = virtnet_receive_xsk(dev, vi, rq, buf, len, xdp_xmit, stats); + else if (vi->mergeable_rx_bufs) skb = receive_mergeable(dev, vi, rq, buf, ctx, len, xdp_xmit, stats); else if (vi->big_packets) diff --git a/drivers/net/virtio/virtio_net.h b/drivers/net/virtio/virtio_net.h index 2005d0cd22e2..f520fec06662 100644 --- a/drivers/net/virtio/virtio_net.h +++ b/drivers/net/virtio/virtio_net.h @@ -339,4 +339,8 @@ void virtnet_tx_pause(struct virtnet_info *vi, struct virtnet_sq *sq); void virtnet_tx_resume(struct virtnet_info *vi, struct virtnet_sq *sq); void virtnet_sq_free_unused_buf(struct virtqueue *vq, void *buf); void virtnet_rq_free_unused_buf(struct virtqueue *vq, void *buf); +int virtnet_xdp_handler(struct bpf_prog *xdp_prog, struct xdp_buff *xdp, + struct net_device *dev, + unsigned int *xdp_xmit, + struct virtnet_rq_stats *stats); #endif diff --git a/drivers/net/virtio/xsk.c b/drivers/net/virtio/xsk.c index b09c473c29fb..5c7eb19ab04b 100644 --- a/drivers/net/virtio/xsk.c +++ b/drivers/net/virtio/xsk.c @@ -14,6 +14,18 @@ static void sg_fill_dma(struct scatterlist *sg, dma_addr_t addr, u32 len) sg->length = len; } +static unsigned int virtnet_receive_buf_num(struct virtnet_info *vi, char *buf) +{ + struct virtio_net_hdr_mrg_rxbuf *hdr; + + if (vi->mergeable_rx_bufs) { + hdr = (struct virtio_net_hdr_mrg_rxbuf *)buf; + return virtio16_to_cpu(vi->vdev, hdr->num_buffers); + } + + return 1; +} + static void virtnet_xsk_check_queue(struct virtnet_sq *sq) { struct virtnet_info *vi = sq->vq->vdev->priv; @@ -38,6 +50,114 @@ static void virtnet_xsk_check_queue(struct virtnet_sq *sq) netif_stop_subqueue(dev, qnum); } +static void merge_drop_follow_xdp(struct net_device *dev, + struct virtnet_rq *rq, + u32 num_buf, + struct virtnet_rq_stats *stats) +{ + struct xdp_buff *xdp; + u32 len; + + while (num_buf-- > 1) { + xdp = virtqueue_get_buf(rq->vq, &len); + if (unlikely(!xdp)) { + pr_debug("%s: rx error: %d buffers missing\n", + dev->name, num_buf); + dev->stats.rx_length_errors++; + break; + } + u64_stats_add(&stats->bytes, len); + xsk_buff_free(xdp); + } +} + +static struct sk_buff *construct_skb(struct virtnet_rq *rq, + struct xdp_buff *xdp) +{ + unsigned int metasize = xdp->data - xdp->data_meta; + struct sk_buff *skb; + unsigned int size; + + size = xdp->data_end - xdp->data_hard_start; + skb = napi_alloc_skb(&rq->napi, size); + if (unlikely(!skb)) + return NULL; + + skb_reserve(skb, xdp->data_meta - xdp->data_hard_start); + + size = xdp->data_end - xdp->data_meta; + memcpy(__skb_put(skb, size), xdp->data_meta, size); + + if (metasize) { + __skb_pull(skb, metasize); + skb_metadata_set(skb, metasize); + } + + return skb; +} + +struct sk_buff *virtnet_receive_xsk(struct net_device *dev, struct virtnet_info *vi, + struct virtnet_rq *rq, void *buf, + unsigned int len, unsigned int *xdp_xmit, + struct virtnet_rq_stats *stats) +{ + struct virtio_net_hdr_mrg_rxbuf *hdr; + struct sk_buff *skb = NULL; + u32 ret, headroom, num_buf; + struct bpf_prog *prog; + struct xdp_buff *xdp; + + len -= vi->hdr_len; + + xdp = (struct xdp_buff *)buf; + + xsk_buff_set_size(xdp, len); + + hdr = xdp->data - vi->hdr_len; + + num_buf = virtnet_receive_buf_num(vi, (char *)hdr); + if (num_buf > 1) + goto drop; + + headroom = xdp->data - xdp->data_hard_start; + + xdp_prepare_buff(xdp, xdp->data_hard_start, headroom, len, true); + xsk_buff_dma_sync_for_cpu(xdp, rq->xsk.pool); + + ret = XDP_PASS; + rcu_read_lock(); + prog = rcu_dereference(rq->xdp_prog); + if (prog) + ret = virtnet_xdp_handler(prog, xdp, dev, xdp_xmit, stats); + rcu_read_unlock(); + + switch (ret) { + case XDP_PASS: + skb = construct_skb(rq, xdp); + xsk_buff_free(xdp); + break; + + case XDP_TX: + case XDP_REDIRECT: + goto consumed; + + default: + goto drop; + } + + return skb; + +drop: + u64_stats_inc(&stats->drops); + + xsk_buff_free(xdp); + + if (num_buf > 1) + merge_drop_follow_xdp(dev, rq, num_buf, stats); +consumed: + return NULL; +} + int virtnet_add_recvbuf_xsk(struct virtnet_info *vi, struct virtnet_rq *rq, struct xsk_buff_pool *pool, gfp_t gfp) { diff --git a/drivers/net/virtio/xsk.h b/drivers/net/virtio/xsk.h index bef41a3f954e..dbd2839a5f61 100644 --- a/drivers/net/virtio/xsk.h +++ b/drivers/net/virtio/xsk.h @@ -25,4 +25,8 @@ bool virtnet_xsk_xmit(struct virtnet_sq *sq, struct xsk_buff_pool *pool, 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); +struct sk_buff *virtnet_receive_xsk(struct net_device *dev, struct virtnet_info *vi, + struct virtnet_rq *rq, void *buf, + unsigned int len, unsigned int *xdp_xmit, + struct virtnet_rq_stats *stats); #endif
The virtnet_xdp_handler() is re-used. But 1. We need to copy data to create skb for XDP_PASS. 2. We need to call xsk_buff_free() to release the buffer. 3. The handle for xdp_buff is difference. If we pushed this logic into existing receive handle(merge and small), we would have to maintain code scattered inside merge and small (and big). So I think it is a good choice for us to put the xsk code into an independent function. Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com> --- drivers/net/virtio/main.c | 12 ++-- drivers/net/virtio/virtio_net.h | 4 ++ drivers/net/virtio/xsk.c | 120 ++++++++++++++++++++++++++++++++ drivers/net/virtio/xsk.h | 4 ++ 4 files changed, 135 insertions(+), 5 deletions(-)