Re: [PATCH net-next v4 07/10] virtio-net: virtnet_poll_tx support budget check
From: Jason Wang <jasowang@redhat.com>
Date: 2021-04-14 03:34:23
Also in:
bpf, virtualization
在 2021/4/13 上午11:15, Xuan Zhuo 写道:
virtnet_poll_tx() check the work done like other network card drivers. When work < budget, napi_poll() in dev.c will exit directly. And virtqueue_napi_complete() will be called to close napi. If closing napi fails or there is still data to be processed, virtqueue_napi_complete() will make napi schedule again, and no conflicts with the logic of napi_poll(). When work == budget, virtnet_poll_tx() will return the var 'work', and the napi_poll() in dev.c will re-add napi to the queue. The purpose of this patch is to support xsk xmit in virtio_poll_tx for subsequent patch. Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Acked-by: Jason Wang <jasowang@redhat.com>
quoted hunk ↗ jump to hunk
--- drivers/net/virtio_net.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index f3752b254965..f52a25091322 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c@@ -1529,6 +1529,7 @@ static int virtnet_poll_tx(struct napi_struct *napi, int budget) struct virtnet_info *vi = sq->vq->vdev->priv; unsigned int index = vq2txq(sq->vq); struct netdev_queue *txq; + int work_done = 0; if (unlikely(is_xdp_raw_buffer_queue(vi, index))) { /* We don't need to enable cb for XDP */@@ -1541,12 +1542,13 @@ static int virtnet_poll_tx(struct napi_struct *napi, int budget) free_old_xmit(sq, true); __netif_tx_unlock(txq); - virtqueue_napi_complete(napi, sq->vq, 0); + if (work_done < budget) + virtqueue_napi_complete(napi, sq->vq, 0); if (sq->vq->num_free >= 2 + MAX_SKB_FRAGS) netif_tx_wake_queue(txq); - return 0; + return work_done; } static int xmit_skb(struct send_queue *sq, struct sk_buff *skb)