linux-toradex.git/include/linux/tcp.h, branch v2.6.22.13

[SK_BUFF]: Introduce skb_transport_header(skb)

2007-04-26T05:25:31+00:00

For the places where we need a pointer to the transport header, it is
still legal to touch skb->h.raw directly if just adding to,
subtracting from or setting it to another layer header.

Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: David S. Miller

[SK_BUFF]: Introduce tcp_hdr(), remove skb->h.th

2007-04-26T05:25:26+00:00

Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: David S. Miller

[TCP]: Introduce tcp_hdrlen() and tcp_optlen()

2007-04-26T05:25:24+00:00

The ip_hdrlen() buddy, created to reduce the number of skb->h.th-> uses and to
avoid the longer, open coded equivalent.

Ditched a no-op in bnx2 in the process.

I wonder if we should have a BUG_ON(skb->h.th->doff < 5) in tcp_optlen()...

Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: David S. Miller

[TCP]: Make snd_cwnd_clamp a u32.

2007-04-26T05:23:21+00:00

Signed-off-by: David S. Miller

[TCP]: Keep copied_seq, rcv_wup and rcv_next together.

2007-04-26T05:23:21+00:00

I noticed in oprofile study a cache miss in tcp_rcv_established() to read
copied_seq.

ffffffff80400a80 : /* tcp_rcv_established total: 4034293  
2.0400 */

 55493  0.0281 :ffffffff80400bc9:   mov    0x4c8(%r12),%eax copied_seq
543103  0.2746 :ffffffff80400bd1:   cmp    0x3e0(%r12),%eax   rcv_nxt    

if (tp->copied_seq == tp->rcv_nxt &&
        len - tcp_header_len <= tp->ucopy.len) {

In this function, the cache line 0x4c0 -> 0x500 is used only for this
reading 'copied_seq' field.

rcv_wup and copied_seq should be next to rcv_nxt field, to lower number of
active cache lines in hot paths. (tcp_rcv_established(), tcp_poll(), ...)

As you suggested, I changed tcp_create_openreq_child() so that these fields
are changed together, to avoid adding a new store buffer stall.

Patch is 64bit friendly (no new hole because of alignment constraints)

Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller

[TCP]: Seperate DSACK from SACK fast path

2007-02-08T20:38:49+00:00

Move DSACK code outside the SACK fast-path checking code. If the DSACK
determined that the information was too old we stayed with a partial cache
copied. Most likely this matters very little since the next packet will not be
DSACK and we will find it in the cache. but it's still not good form and there
is little reason to couple the two checks.

Since the SACK receive cache doesn't need the data to be in host order we also
remove the ntohl in the checking loop.

Signed-off-by: Baruch Even 
Signed-off-by: David S. Miller

[TCP]: Renove the __ prefix on the struct tcp_sock members

2006-12-03T05:30:54+00:00

As this struct is not userland visible at all.

Signed-off-by: Arnaldo Carvalho de Melo

[TCP]: Change tcp_header_len member in tcp_sock to u16

2006-12-03T05:30:53+00:00

With this we eliminate the last hole in struct tcp_sock.

End result:

[acme@newtoy net-2.6.20]$ codiff -sV /tmp/tcp.o.before net/ipv4/tcp.o
/pub/scm/linux/kernel/git/acme/net-2.6.20/net/ipv4/tcp.c:
  struct tcp_sock |   -4
    tcp_header_len;
     from: int                   /*  1000(0)     4(0) */
     to:   u16                   /*  1000(0)     2(0) */
 1 struct changed
[acme@newtoy net-2.6.20]$

Now sizeof(tcp_sock) is just...

[acme@newtoy net-2.6.20]$ pahole --sizes ../OUTPUT/qemu/net-2.6.20/net/ipv4/tcp.o | grep -w tcp_sock
struct tcp_sock: 1500 0

1500 bytes ;-)

Signed-off-by: Arnaldo Carvalho de Melo

[NET]: Annotate checksums in on-the-wire packets.

2006-12-03T05:23:26+00:00

Signed-off-by: Al Viro 
Signed-off-by: David S. Miller

[TCP]: MD5 Signature Option (RFC2385) support.

2006-12-03T05:22:39+00:00

Based on implementation by Rick Payne.

Signed-off-by: YOSHIFUJI Hideaki 
Signed-off-by: David S. Miller