diff mbox

[net-next] tcp: remove from tcp_sendmsg() some fastopen code

Message ID 1416500634.8629.31.camel@edumazet-glaptop2.roam.corp.google.com
State Rejected, archived
Delegated to: David Miller
Headers show

Commit Message

Eric Dumazet Nov. 20, 2014, 4:23 p.m. UTC 
From: Eric Dumazet <edumazet@google.com>

If we consume iovec bytes in tcp_send_syn_data(), we can remove
annoying fastopen code in tcp_sendmsg() skipping over the already
consumed bytes.

Also add an unlikely(flags & MSG_FASTOPEN), as most TCP sendmsg() do not
ask for FASTOPEN.

Tested:
 Ran our 125 packetdrill fastopen tests

Signed-off-by: Eric Dumazet <edumazet@google.com>
---
 net/ipv4/tcp.c        |   14 ++------------
 net/ipv4/tcp_output.c |    4 ++--
 2 files changed, 4 insertions(+), 14 deletions(-)



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Comments

Eric Dumazet Nov. 20, 2014, 11:05 p.m. UTC | #1 
On Thu, 2014-11-20 at 08:23 -0800, Eric Dumazet wrote:
> From: Eric Dumazet <edumazet@google.com>
> 
> If we consume iovec bytes in tcp_send_syn_data(), we can remove
> annoying fastopen code in tcp_sendmsg() skipping over the already
> consumed bytes.
> 
> Also add an unlikely(flags & MSG_FASTOPEN), as most TCP sendmsg() do not
> ask for FASTOPEN.
> 
> Tested:
>  Ran our 125 packetdrill fastopen tests
> 
> Signed-off-by: Eric Dumazet <edumazet@google.com>
> ---

Please disregard this patch, Al Viro said sendmsg() was apparently not
allowed to change iovec.

Some callers depend on it staying constant.

Not clear why memcpy_fromiovec() even exists.



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diff mbox

Patch

diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index c239f4740d10b10b67ef4fa44c831851fb9e1dcf..227540eef9d0870721258f9ddbace27b417c619e 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -1089,20 +1089,19 @@  int tcp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
 	struct tcp_sock *tp = tcp_sk(sk);
 	struct sk_buff *skb;
 	int iovlen, flags, err, copied = 0;
-	int mss_now = 0, size_goal, copied_syn = 0, offset = 0;
+	int mss_now = 0, size_goal, copied_syn = 0;
 	bool sg;
 	long timeo;
 
 	lock_sock(sk);
 
 	flags = msg->msg_flags;
-	if (flags & MSG_FASTOPEN) {
+	if (unlikely(flags & MSG_FASTOPEN)) {
 		err = tcp_sendmsg_fastopen(sk, msg, &copied_syn, size);
 		if (err == -EINPROGRESS && copied_syn > 0)
 			goto out;
 		else if (err)
 			goto out_err;
-		offset = copied_syn;
 	}
 
 	timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
@@ -1151,15 +1150,6 @@  int tcp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
 		unsigned char __user *from = iov->iov_base;
 
 		iov++;
-		if (unlikely(offset > 0)) {  /* Skip bytes copied in SYN */
-			if (offset >= seglen) {
-				offset -= seglen;
-				continue;
-			}
-			seglen -= offset;
-			from += offset;
-			offset = 0;
-		}
 
 		while (seglen > 0) {
 			int copy = 0;
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index f5bd4bd3f7e669b3fd48a843d55e7313a30a3409..524e5b657e881a348f11def3f48f29a76f54fbab 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -3049,8 +3049,8 @@  static int tcp_send_syn_data(struct sock *sk, struct sk_buff *syn)
 		goto fallback;
 	syn_data->ip_summed = CHECKSUM_PARTIAL;
 	memcpy(syn_data->cb, syn->cb, sizeof(syn->cb));
-	if (unlikely(memcpy_fromiovecend(skb_put(syn_data, space),
-					 fo->data->msg_iov, 0, space))) {
+	if (unlikely(memcpy_fromiovec(skb_put(syn_data, space),
+				      fo->data->msg_iov, space))) {
 		kfree_skb(syn_data);
 		goto fallback;
 	}