| Message ID | 20090629040641.GA3357@gondor.apana.org.au |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
From: Herbert Xu <herbert@gondor.apana.org.au> Date: Mon, 29 Jun 2009 12:06:41 +0800 > On Mon, Jun 29, 2009 at 12:03:30PM +0800, Herbert Xu wrote: >> >> tcp: Stop non-TSO packets morphing into TSO > > Here's a follow-up patch to optimise this boundary case. > > tcp: Do not tack on TSO data to non-TSO packet > > If a socket starts out on a non-TSO route, and then switches to > a TSO route, then we will tack on data to the tail of the tx queue > even if it started out life as non-TSO. This is suboptimal because > all of it will then be copied and checksummed unnecessarily. > > This patch fixes this by ensuring that skb->ip_summed is set to > CHECKSUM_PARTIAL before appending extra data beyond the MSS. > > Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Applied. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 17b89c5..7870a53 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -903,13 +903,17 @@ int tcp_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg, iov++; while (seglen > 0) { - int copy; + int copy = 0; + int max = size_goal; skb = tcp_write_queue_tail(sk); + if (tcp_send_head(sk)) { + if (skb->ip_summed == CHECKSUM_NONE) + max = mss_now; + copy = max - skb->len; + } - if (!tcp_send_head(sk) || - (copy = size_goal - skb->len) <= 0) { - + if (copy <= 0) { new_segment: /* Allocate new segment. If the interface is SG, * allocate skb fitting to single page. @@ -930,6 +934,7 @@ new_segment: skb_entail(sk, skb); copy = size_goal; + max = size_goal; } /* Try to append data to the end of skb. */ @@ -1028,7 +1033,7 @@ new_segment: if ((seglen -= copy) == 0 && iovlen == 0) goto out; - if (skb->len < size_goal || (flags & MSG_OOB)) + if (skb->len < max || (flags & MSG_OOB)) continue; if (forced_push(tp)) {