tuntap: correctly add the missing XDP flush

We don't flush batched XDP packets through xdp_do_flush_map(), this
will cause packets stall at TX queue. Consider we don't do XDP on NAPI
poll(), the only possible fix is to call xdp_do_flush_map()
immediately after xdp_do_redirect().

Note, this in fact won't try to batch packets through devmap, we could
address in the future.

Reported-by: Christoffer Dall <christoffer.dall@linaro.org>
Fixes: 761876c857 ("tap: XDP support")
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Jason Wang 2018-02-24 11:32:26 +08:00 committed by David S. Miller
parent 23e43f07f8
commit 1bb4f2e868

View File

@ -1663,6 +1663,7 @@ static struct sk_buff *tun_build_skb(struct tun_struct *tun,
get_page(alloc_frag->page);
alloc_frag->offset += buflen;
err = xdp_do_redirect(tun->dev, &xdp, xdp_prog);
xdp_do_flush_map();
if (err)
goto err_redirect;
rcu_read_unlock();