[PATCH net-next v2 10/21] virtio_net: xsk: prevent disable tx napi

Xuan Zhuo
2023-11-07T03:12:46Z

Since xsk's TX queue is consumed by TX NAPI, if sq is bound to xsk, then
we must stop tx napi from being disabled.

Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Acked-by: Jason Wang <jasowang@redhat.com>
---
drivers/net/virtio/main.c | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/drivers/net/virtio/main.c b/drivers/net/virtio/main.c
index c4601784b6d1..02e054fd217c 100644
--- a/drivers/net/virtio/main.c
+++ b/drivers/net/virtio/main.c
@@ -3337,7 +3337,7 @@ static int virtnet_set_coalesce(struct net_device *dev,
struct netlink_ext_ack *extack)
{
struct virtnet_info *vi = netdev_priv(dev);
- int ret, queue_number, napi_weight;
+ int ret, queue_number, napi_weight, i;
bool update_napi = false;

/* Can't change NAPI weight if the link is up */
@@ -3366,6 +3366,14 @@ static int virtnet_set_coalesce(struct net_device *dev,
return ret;

if (update_napi) {
+ /* xsk xmit depends on the tx napi. So if xsk is active,
+ * prevent modifications to tx napi.
+ */
+ for (i = queue_number; i < vi->max_queue_pairs; i++) {
+ if (vi->sq[i].xsk.pool)
+ return -EBUSY;
+ }
+
for (; queue_number < vi->max_queue_pairs; queue_number++)
vi->sq[queue_number].napi.weight = napi_weight;
}
--
2.32.0.3.g01195cf9f