From 9684f5e7c8cdf076aeec81344d4893a30f7aa6a1 Mon Sep 17 00:00:00 2001 From: Magnus Karlsson Date: Wed, 11 Jul 2018 10:12:50 +0200 Subject: [PATCH] xsk: do not return EAGAIN from sendmsg when completion queue is full This patch stops returning EAGAIN in TX copy mode when the completion queue is full as zero-copy does not do this. Instead this situation can be detected by comparing the head and tail pointers of the completion queue in both modes. In any case, EAGAIN was not the correct error code here since no amount of calling sendmsg will solve the problem. Only consuming one or more messages on the completion queue will fix this. With this patch, the error reporting becomes consistent between copy mode and zero-copy mode. Fixes: 35fcde7f8deb ("xsk: support for Tx") Signed-off-by: Magnus Karlsson Signed-off-by: Daniel Borkmann --- 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 08d09115093e..87567232d0f8 100644 --- a/net/xdp/xsk.c +++ b/net/xdp/xsk.c @@ -233,10 +233,8 @@ static int xsk_generic_xmit(struct sock *sk, struct msghdr *m, goto out; } - if (xskq_reserve_addr(xs->umem->cq)) { - err = -EAGAIN; + if (xskq_reserve_addr(xs->umem->cq)) goto out; - } len = desc.len; if (unlikely(len > xs->dev->mtu)) {