xdp_return_buff() is used when frame has been successfully
handled (transmitted) or if an error occurred during delayed
processing and there is no way to report it back to
xdp_do_redirect().
In case of __xsk_rcv_zc() error is propagated all the way
back to the driver, so there is no need to call
xdp_return_buff(). Driver will recycle the frame anyway
after seeing that error happened.
Fixes: 173d3adb6f43 ("xsk: add zero-copy support for Rx")
Signed-off-by: Jakub Kicinski <jakub.kicin...@netronome.com>
---
Patch could as well be applied to bpf-next, since there are no drivers
for AF_XDP in tree, yet. xdp_umem_get_dma() and xdp_umem_get_data() are
not even exported. But one could reimplent those...
As I mentioned I think this makes the entire MEM_TYPE_ZERO_COPY allocator
handling dead code now :(
net/xdp/xsk.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)
diff --git a/net/xdp/xsk.c b/net/xdp/xsk.c
index 72335c2e8108..4e937cd7c17d 100644
--- a/net/xdp/xsk.c
+++ b/net/xdp/xsk.c
@@ -84,10 +84,8 @@ static int __xsk_rcv_zc(struct xdp_sock *xs, struct xdp_buff
*xdp, u32 len)
{
int err = xskq_produce_batch_desc(xs->rx, (u64)xdp->handle, len);
- if (err) {
- xdp_return_buff(xdp);
+ if (err)
xs->rx_dropped++;
- }
return err;
}
--
2.17.1
