Commit 4d6308aa authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller

virtio_net: exploit napi_complete_done() return value

Since commit 364b6055 ("net: busy-poll: return busypolling status to
drivers"), napi_complete_done() returns a boolean that can be used
by drivers to conditionally rearm interrupts.

This patch changes virtio_net to use this boolean to avoid a bit of
overhead for busy-poll users.

Jason reports about 1.1% improvement for 1 byte TCP_RR (burst 100).
Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Acked-by: default avatarJason Wang <jasowang@redhat.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent a076d1bd
......@@ -1012,13 +1012,14 @@ static int virtnet_poll(struct napi_struct *napi, int budget)
/* Out of packets? */
if (received < budget) {
r = virtqueue_enable_cb_prepare(rq->vq);
napi_complete_done(napi, received);
if (napi_complete_done(napi, received)) {
if (unlikely(virtqueue_poll(rq->vq, r)) &&
napi_schedule_prep(napi)) {
virtqueue_disable_cb(rq->vq);
__napi_schedule(napi);
}
}
}
return received;
}
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment