On Wed, 19 Dec 2007, Ilpo Järvinen wrote:
> I'm not fully sure what's purpose of this code in tcp_write_xmit:
>
> if (skb->len < limit) {
> unsigned int trim = skb->len % mss_now;
>
> if (trim)
> limit = skb->len - trim;
> }
>
> Is it used to make sure we send only multiples of mss_now here and leave
> the left-over into another skb? Or does it try to make sure that
> tso_fragment result honors multiple of mss_now boundaries when snd_wnd
> is the limitting factor? For latter IMHO this would be necessary:
>
> if (skb->len > limit)
> limit -= limit % mss_now;
...Anyway, here's an untested patch to just do it :-):
--
i.
[PATCH] [TCP]: Force tso skb split to mss_now boundary (if snd_wnd limits)
If snd_wnd was limitting factor, the tso_fragment might not
create full-sized skbs but would include the window left-overs
as well.
Signed-off-by: Ilpo Järvinen <[EMAIL PROTECTED]>
---
net/ipv4/tcp_output.c | 4 ++++
1 files changed, 4 insertions(+), 0 deletions(-)
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index 1c7ef17..8dafda9 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -1453,6 +1453,8 @@ static int tcp_write_xmit(struct sock *sk, unsigned int
mss_now, int nonagle)
if (trim)
limit = skb->len - trim;
+ } else if (skb->len > limit) {
+ limit -= limit % mss_now;
}
}
@@ -1525,6 +1527,8 @@ void tcp_push_one(struct sock *sk, unsigned int mss_now)
if (trim)
limit = skb->len - trim;
+ } else if (skb->len > limit) {
+ limit -= limit % mss_now;
}
}
--
1.5.0.6
