From: Menglong Dong <[email protected]> For now, we use sk_busy_loop() in __xsk_sendmsg() to send the data in tx ring. The sk_busy_loop() will poll on the target NAPI. However, for the nic driver that support the tx napi, such as virtio-net, it can't schedule the tx NAPI, but only the rx NAPI. If we enable the busy_poll for xsk and use virtio-net, we can't send data, as the rx NAPI in virtio-net doesn't handle the packet sending.
Fix this by introduce the sk_tx_busy_loop(), which will poll on the tx NAPI if available. To get the tx NAPI from the napi_id, we add the "tx_napi" field to napi_struct, which is ugly :/ Another choice is to call virtnet_xsk_xmit() in virtnet_poll() too. But this a little contradict the design of tx NAPI. Menglong Dong (3): net: busy-poll: introduce sk_tx_busy_loop() virtio_net: initialize napi.tx_napi in virtnet_alloc_queues() xsk: replace sk_busy_loop with sk_tx_busy_loop in __xsk_sendmsg() drivers/net/virtio_net.c | 1 + include/linux/netdevice.h | 1 + include/net/busy_poll.h | 41 ++++++++++++++++++++++++++++++++++++--- net/core/dev.c | 23 +++++----------------- net/xdp/xsk.c | 2 +- 5 files changed, 46 insertions(+), 22 deletions(-) -- 2.54.0
