[PATCH net-next v2 7/7] virtio-net, xsk: set xsk completed when packet sent done

[Xuan Zhuo]

When recycling packets that have been sent, call xsk_tx_completed to
inform xsk which packets have been sent.

If necessary, start napi to process the packets in the xsk queue.

Signed-off-by: Xuan Zhuo <xuanz...@linux.alibaba.com>
---
 drivers/net/virtio_net.c | 49 ++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 49 insertions(+)

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index e552c2d..d0d620b 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -1442,6 +1442,42 @@ static int virtnet_receive(struct receive_queue *rq, int 
budget,
        return stats.packets;
 }
 
+static void virt_xsk_complete(struct send_queue *sq, u32 num, bool xsk_wakeup)
+{
+       struct xsk_buff_pool *pool;
+       struct virtnet_xsk_hdr *hdr = NULL;
+       int n;
+
+       rcu_read_lock();
+
+       sq->xsk.hdr_pro += num;
+
+       pool = rcu_dereference(sq->xsk.pool);
+       if (!pool) {
+               if (sq->xsk.hdr_pro - sq->xsk.hdr_con == sq->xsk.hdr_n)
+                       hdr = rcu_replace_pointer(sq->xsk.hdr, hdr, true);
+
+               rcu_read_unlock();
+
+               kfree(hdr);
+               return;
+       }
+
+       xsk_tx_completed(pool, num);
+
+       rcu_read_unlock();
+
+       if (!xsk_wakeup || !sq->xsk.wait_slot)
+               return;
+
+       n = sq->xsk.hdr_pro - sq->xsk.hdr_con;
+
+       if (n > sq->xsk.hdr_n / 2) {
+               sq->xsk.wait_slot = false;
+               virtqueue_napi_schedule(&sq->napi, sq->vq);
+       }
+}
+
 static void __free_old_xmit_ptr(struct send_queue *sq, bool in_napi,
                                bool xsk_wakeup,
                                unsigned int *_packets, unsigned int *_bytes)
@@ -1449,6 +1485,7 @@ static void __free_old_xmit_ptr(struct send_queue *sq, 
bool in_napi,
        unsigned int packets = 0;
        unsigned int bytes = 0;
        unsigned int len;
+       u64 xsknum = 0;
        struct virtnet_xdp_type *xtype;
        struct xdp_frame        *frame;
        struct virtnet_xsk_hdr  *xskhdr;
@@ -1469,6 +1506,7 @@ static void __free_old_xmit_ptr(struct send_queue *sq, 
bool in_napi,
                        if (xtype->type == XDP_TYPE_XSK) {
                                xskhdr = (struct virtnet_xsk_hdr *)xtype;
                                bytes += xskhdr->len;
+                               xsknum += 1;
                        } else {
                                frame = xtype_get_ptr(xtype);
                                xdp_return_frame(frame);
@@ -1478,6 +1516,9 @@ static void __free_old_xmit_ptr(struct send_queue *sq, 
bool in_napi,
                packets++;
        }
 
+       if (xsknum)
+               virt_xsk_complete(sq, xsknum, xsk_wakeup);
+
        *_packets = packets;
        *_bytes = bytes;
 }
@@ -3044,10 +3085,13 @@ static void free_receive_page_frags(struct virtnet_info 
*vi)
 static void free_unused_bufs(struct virtnet_info *vi)
 {
        void *buf;
+       u32 n;
        int i;
+       struct send_queue *sq;
 
        for (i = 0; i < vi->max_queue_pairs; i++) {
                struct virtqueue *vq = vi->sq[i].vq;
+               sq = vi->sq + i;
                while ((buf = virtqueue_detach_unused_buf(vq)) != NULL) {
                        if (!is_xdp_frame(buf)) {
                                dev_kfree_skb(buf);
@@ -3060,6 +3104,11 @@ static void free_unused_bufs(struct virtnet_info *vi)
                                        xdp_return_frame(xtype_get_ptr(xtype));
                        }
                }
+
+               n = sq->xsk.hdr_con + sq->xsk.hdr_n;
+               n -= sq->xsk.hdr_pro;
+               if (n)
+                       virt_xsk_complete(sq, n, false);
        }
 
        for (i = 0; i < vi->max_queue_pairs; i++) {
-- 
1.8.3.1