Xuan Zhuo
2023-Apr-23 10:57 UTC
[PATCH net-next v3 10/15] virtio_net: introduce receive_small_xdp()
The purpose of this patch is to simplify the receive_small().
Separate all the logic of XDP of small into a function.
Signed-off-by: Xuan Zhuo <xuanzhuo at linux.alibaba.com>
---
drivers/net/virtio_net.c | 165 ++++++++++++++++++++++++---------------
1 file changed, 100 insertions(+), 65 deletions(-)
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index de5a579e8603..9b5fd2e0d27f 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -931,6 +931,99 @@ static struct page *xdp_linearize_page(struct receive_queue
*rq,
return NULL;
}
+static struct sk_buff *receive_small_xdp(struct net_device *dev,
+ struct virtnet_info *vi,
+ struct receive_queue *rq,
+ struct bpf_prog *xdp_prog,
+ void *buf,
+ unsigned int xdp_headroom,
+ unsigned int len,
+ unsigned int *xdp_xmit,
+ struct virtnet_rq_stats *stats)
+{
+ unsigned int header_offset = VIRTNET_RX_PAD + xdp_headroom;
+ unsigned int headroom = vi->hdr_len + header_offset;
+ struct virtio_net_hdr_mrg_rxbuf *hdr = buf + header_offset;
+ struct page *page = virt_to_head_page(buf);
+ struct page *xdp_page;
+ unsigned int buflen;
+ struct xdp_buff xdp;
+ struct sk_buff *skb;
+ unsigned int delta = 0;
+ unsigned int metasize = 0;
+ void *orig_data;
+ u32 act;
+
+ if (unlikely(hdr->hdr.gso_type))
+ goto err_xdp;
+
+ buflen = SKB_DATA_ALIGN(GOOD_PACKET_LEN + headroom) +
+ SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
+
+ if (unlikely(xdp_headroom < virtnet_get_headroom(vi))) {
+ int offset = buf - page_address(page) + header_offset;
+ unsigned int tlen = len + vi->hdr_len;
+ int num_buf = 1;
+
+ xdp_headroom = virtnet_get_headroom(vi);
+ header_offset = VIRTNET_RX_PAD + xdp_headroom;
+ headroom = vi->hdr_len + header_offset;
+ buflen = SKB_DATA_ALIGN(GOOD_PACKET_LEN + headroom) +
+ SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
+ xdp_page = xdp_linearize_page(rq, &num_buf, page,
+ offset, header_offset,
+ &tlen);
+ if (!xdp_page)
+ goto err_xdp;
+
+ buf = page_address(xdp_page);
+ put_page(page);
+ page = xdp_page;
+ }
+
+ xdp_init_buff(&xdp, buflen, &rq->xdp_rxq);
+ xdp_prepare_buff(&xdp, buf + VIRTNET_RX_PAD + vi->hdr_len,
+ xdp_headroom, len, true);
+ orig_data = xdp.data;
+
+ act = virtnet_xdp_handler(xdp_prog, &xdp, dev, xdp_xmit, stats);
+
+ switch (act) {
+ case XDP_PASS:
+ /* Recalculate length in case bpf program changed it */
+ delta = orig_data - xdp.data;
+ len = xdp.data_end - xdp.data;
+ metasize = xdp.data - xdp.data_meta;
+ break;
+
+ case XDP_TX:
+ case XDP_REDIRECT:
+ goto xdp_xmit;
+
+ default:
+ goto err_xdp;
+ }
+
+ skb = build_skb(buf, buflen);
+ if (!skb)
+ goto err;
+
+ skb_reserve(skb, headroom - delta);
+ skb_put(skb, len);
+ if (metasize)
+ skb_metadata_set(skb, metasize);
+
+ return skb;
+
+err_xdp:
+ stats->xdp_drops++;
+err:
+ stats->drops++;
+ put_page(page);
+xdp_xmit:
+ return NULL;
+}
+
static struct sk_buff *receive_small(struct net_device *dev,
struct virtnet_info *vi,
struct receive_queue *rq,
@@ -947,9 +1040,6 @@ static struct sk_buff *receive_small(struct net_device
*dev,
unsigned int buflen = SKB_DATA_ALIGN(GOOD_PACKET_LEN + headroom) +
SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
struct page *page = virt_to_head_page(buf);
- unsigned int delta = 0;
- struct page *xdp_page;
- unsigned int metasize = 0;
len -= vi->hdr_len;
stats->bytes += len;
@@ -969,56 +1059,10 @@ static struct sk_buff *receive_small(struct net_device
*dev,
rcu_read_lock();
xdp_prog = rcu_dereference(rq->xdp_prog);
if (xdp_prog) {
- struct virtio_net_hdr_mrg_rxbuf *hdr = buf + header_offset;
- struct xdp_buff xdp;
- void *orig_data;
- u32 act;
-
- if (unlikely(hdr->hdr.gso_type))
- goto err_xdp;
-
- if (unlikely(xdp_headroom < virtnet_get_headroom(vi))) {
- int offset = buf - page_address(page) + header_offset;
- unsigned int tlen = len + vi->hdr_len;
- int num_buf = 1;
-
- xdp_headroom = virtnet_get_headroom(vi);
- header_offset = VIRTNET_RX_PAD + xdp_headroom;
- headroom = vi->hdr_len + header_offset;
- buflen = SKB_DATA_ALIGN(GOOD_PACKET_LEN + headroom) +
- SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
- xdp_page = xdp_linearize_page(rq, &num_buf, page,
- offset, header_offset,
- &tlen);
- if (!xdp_page)
- goto err_xdp;
-
- buf = page_address(xdp_page);
- put_page(page);
- page = xdp_page;
- }
-
- xdp_init_buff(&xdp, buflen, &rq->xdp_rxq);
- xdp_prepare_buff(&xdp, buf + VIRTNET_RX_PAD + vi->hdr_len,
- xdp_headroom, len, true);
- orig_data = xdp.data;
-
- act = virtnet_xdp_handler(xdp_prog, &xdp, dev, xdp_xmit, stats);
-
- switch (act) {
- case XDP_PASS:
- /* Recalculate length in case bpf program changed it */
- delta = orig_data - xdp.data;
- len = xdp.data_end - xdp.data;
- metasize = xdp.data - xdp.data_meta;
- break;
- case XDP_TX:
- case XDP_REDIRECT:
- rcu_read_unlock();
- goto xdp_xmit;
- default:
- goto err_xdp;
- }
+ skb = receive_small_xdp(dev, vi, rq, xdp_prog, buf, xdp_headroom,
+ len, xdp_xmit, stats);
+ rcu_read_unlock();
+ return skb;
}
rcu_read_unlock();
@@ -1026,25 +1070,16 @@ static struct sk_buff *receive_small(struct net_device
*dev,
skb = build_skb(buf, buflen);
if (!skb)
goto err;
- skb_reserve(skb, headroom - delta);
+ skb_reserve(skb, headroom);
skb_put(skb, len);
- if (!xdp_prog) {
- buf += header_offset;
- memcpy(skb_vnet_hdr(skb), buf, vi->hdr_len);
- } /* keep zeroed vnet hdr since XDP is loaded */
-
- if (metasize)
- skb_metadata_set(skb, metasize);
+ buf += header_offset;
+ memcpy(skb_vnet_hdr(skb), buf, vi->hdr_len);
return skb;
-err_xdp:
- rcu_read_unlock();
- stats->xdp_drops++;
err:
stats->drops++;
put_page(page);
-xdp_xmit:
return NULL;
}
--
2.32.0.3.g01195cf9f
Jason Wang
2023-Apr-25 07:58 UTC
[PATCH net-next v3 10/15] virtio_net: introduce receive_small_xdp()
On Sun, Apr 23, 2023 at 6:58?PM Xuan Zhuo <xuanzhuo at linux.alibaba.com> wrote:> > The purpose of this patch is to simplify the receive_small(). > Separate all the logic of XDP of small into a function. > > Signed-off-by: Xuan Zhuo <xuanzhuo at linux.alibaba.com> > --- > drivers/net/virtio_net.c | 165 ++++++++++++++++++++++++--------------- > 1 file changed, 100 insertions(+), 65 deletions(-) > > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c > index de5a579e8603..9b5fd2e0d27f 100644 > --- a/drivers/net/virtio_net.c > +++ b/drivers/net/virtio_net.c > @@ -931,6 +931,99 @@ static struct page *xdp_linearize_page(struct receive_queue *rq, > return NULL; > } > > +static struct sk_buff *receive_small_xdp(struct net_device *dev, > + struct virtnet_info *vi, > + struct receive_queue *rq, > + struct bpf_prog *xdp_prog, > + void *buf, > + unsigned int xdp_headroom, > + unsigned int len, > + unsigned int *xdp_xmit, > + struct virtnet_rq_stats *stats) > +{ > + unsigned int header_offset = VIRTNET_RX_PAD + xdp_headroom; > + unsigned int headroom = vi->hdr_len + header_offset; > + struct virtio_net_hdr_mrg_rxbuf *hdr = buf + header_offset; > + struct page *page = virt_to_head_page(buf); > + struct page *xdp_page; > + unsigned int buflen; > + struct xdp_buff xdp; > + struct sk_buff *skb; > + unsigned int delta = 0; > + unsigned int metasize = 0; > + void *orig_data; > + u32 act; > + > + if (unlikely(hdr->hdr.gso_type)) > + goto err_xdp; > + > + buflen = SKB_DATA_ALIGN(GOOD_PACKET_LEN + headroom) + > + SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); > + > + if (unlikely(xdp_headroom < virtnet_get_headroom(vi))) { > + int offset = buf - page_address(page) + header_offset; > + unsigned int tlen = len + vi->hdr_len; > + int num_buf = 1; > + > + xdp_headroom = virtnet_get_headroom(vi); > + header_offset = VIRTNET_RX_PAD + xdp_headroom; > + headroom = vi->hdr_len + header_offset; > + buflen = SKB_DATA_ALIGN(GOOD_PACKET_LEN + headroom) + > + SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); > + xdp_page = xdp_linearize_page(rq, &num_buf, page, > + offset, header_offset, > + &tlen); > + if (!xdp_page) > + goto err_xdp; > + > + buf = page_address(xdp_page); > + put_page(page); > + page = xdp_page; > + } > + > + xdp_init_buff(&xdp, buflen, &rq->xdp_rxq); > + xdp_prepare_buff(&xdp, buf + VIRTNET_RX_PAD + vi->hdr_len, > + xdp_headroom, len, true); > + orig_data = xdp.data; > + > + act = virtnet_xdp_handler(xdp_prog, &xdp, dev, xdp_xmit, stats); > + > + switch (act) { > + case XDP_PASS: > + /* Recalculate length in case bpf program changed it */ > + delta = orig_data - xdp.data; > + len = xdp.data_end - xdp.data; > + metasize = xdp.data - xdp.data_meta; > + break; > + > + case XDP_TX: > + case XDP_REDIRECT: > + goto xdp_xmit; > + > + default: > + goto err_xdp; > + } > + > + skb = build_skb(buf, buflen); > + if (!skb) > + goto err; > + > + skb_reserve(skb, headroom - delta); > + skb_put(skb, len); > + if (metasize) > + skb_metadata_set(skb, metasize); > + > + return skb; > + > +err_xdp: > + stats->xdp_drops++; > +err: > + stats->drops++; > + put_page(page); > +xdp_xmit: > + return NULL; > +}It looks like some of the comments of the above version is not addressed? " So we end up with some code duplication between receive_small() and receive_small_xdp() on building skbs. Is this intended? " Thanks> + > static struct sk_buff *receive_small(struct net_device *dev, > struct virtnet_info *vi, > struct receive_queue *rq, > @@ -947,9 +1040,6 @@ static struct sk_buff *receive_small(struct net_device *dev, > unsigned int buflen = SKB_DATA_ALIGN(GOOD_PACKET_LEN + headroom) + > SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); > struct page *page = virt_to_head_page(buf); > - unsigned int delta = 0; > - struct page *xdp_page; > - unsigned int metasize = 0; > > len -= vi->hdr_len; > stats->bytes += len; > @@ -969,56 +1059,10 @@ static struct sk_buff *receive_small(struct net_device *dev, > rcu_read_lock(); > xdp_prog = rcu_dereference(rq->xdp_prog); > if (xdp_prog) { > - struct virtio_net_hdr_mrg_rxbuf *hdr = buf + header_offset; > - struct xdp_buff xdp; > - void *orig_data; > - u32 act; > - > - if (unlikely(hdr->hdr.gso_type)) > - goto err_xdp; > - > - if (unlikely(xdp_headroom < virtnet_get_headroom(vi))) { > - int offset = buf - page_address(page) + header_offset; > - unsigned int tlen = len + vi->hdr_len; > - int num_buf = 1; > - > - xdp_headroom = virtnet_get_headroom(vi); > - header_offset = VIRTNET_RX_PAD + xdp_headroom; > - headroom = vi->hdr_len + header_offset; > - buflen = SKB_DATA_ALIGN(GOOD_PACKET_LEN + headroom) + > - SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); > - xdp_page = xdp_linearize_page(rq, &num_buf, page, > - offset, header_offset, > - &tlen); > - if (!xdp_page) > - goto err_xdp; > - > - buf = page_address(xdp_page); > - put_page(page); > - page = xdp_page; > - } > - > - xdp_init_buff(&xdp, buflen, &rq->xdp_rxq); > - xdp_prepare_buff(&xdp, buf + VIRTNET_RX_PAD + vi->hdr_len, > - xdp_headroom, len, true); > - orig_data = xdp.data; > - > - act = virtnet_xdp_handler(xdp_prog, &xdp, dev, xdp_xmit, stats); > - > - switch (act) { > - case XDP_PASS: > - /* Recalculate length in case bpf program changed it */ > - delta = orig_data - xdp.data; > - len = xdp.data_end - xdp.data; > - metasize = xdp.data - xdp.data_meta; > - break; > - case XDP_TX: > - case XDP_REDIRECT: > - rcu_read_unlock(); > - goto xdp_xmit; > - default: > - goto err_xdp; > - } > + skb = receive_small_xdp(dev, vi, rq, xdp_prog, buf, xdp_headroom, > + len, xdp_xmit, stats); > + rcu_read_unlock(); > + return skb; > } > rcu_read_unlock(); > > @@ -1026,25 +1070,16 @@ static struct sk_buff *receive_small(struct net_device *dev, > skb = build_skb(buf, buflen); > if (!skb) > goto err; > - skb_reserve(skb, headroom - delta); > + skb_reserve(skb, headroom); > skb_put(skb, len); > - if (!xdp_prog) { > - buf += header_offset; > - memcpy(skb_vnet_hdr(skb), buf, vi->hdr_len); > - } /* keep zeroed vnet hdr since XDP is loaded */ > - > - if (metasize) > - skb_metadata_set(skb, metasize); > > + buf += header_offset; > + memcpy(skb_vnet_hdr(skb), buf, vi->hdr_len); > return skb; > > -err_xdp: > - rcu_read_unlock(); > - stats->xdp_drops++; > err: > stats->drops++; > put_page(page); > -xdp_xmit: > return NULL; > } > > -- > 2.32.0.3.g01195cf9f >