path: root/net
diff options
authorEric Dumazet <edumazet@google.com>2013-10-15 12:24:54 -0700
committerDavid S. Miller <davem@davemloft.net>2013-10-17 16:08:08 -0400
commit8f26fb1c1ed81c33f5d87c5936f4d9d1b4118918 (patch)
tree0b27f1be92b9291d8a618a2b79f97aa30a60ac20 /net
parentc52e2421f7368fd36cbe330d2cf41b10452e39a9 (diff)
tcp: remove the sk_can_gso() check from tcp_set_skb_tso_segs()
sk_can_gso() should only be used as a hint in tcp_sendmsg() to build GSO packets in the first place. (As a performance hint) Once we have GSO packets in write queue, we can not decide they are no longer GSO only because flow now uses a route which doesn't handle TSO/GSO. Core networking stack handles the case very well for us, all we need is keeping track of packet counts in MSS terms, regardless of segmentation done later (in GSO or hardware) Right now, if tcp_fragment() splits a GSO packet in two parts, @left and @right, and route changed through a non GSO device, both @left and @right have pcount set to 1, which is wrong, and leads to incorrect packet_count tracking. This problem was added in commit d5ac99a648 ("[TCP]: skb pcount with MTU discovery") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Reported-by: Maciej ┼╗enczykowski <maze@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
1 files changed, 1 insertions, 2 deletions
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index 8fad1c15568..d46f2143305 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -989,8 +989,7 @@ static void tcp_set_skb_tso_segs(const struct sock *sk, struct sk_buff *skb,
/* Make sure we own this skb before messing gso_size/gso_segs */
- if (skb->len <= mss_now || !sk_can_gso(sk) ||
- skb->ip_summed == CHECKSUM_NONE) {
+ if (skb->len <= mss_now || skb->ip_summed == CHECKSUM_NONE) {
/* Avoid the costly divide in the normal
* non-TSO case.