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[TCP]: Change tcp_header_len member in tcp_sock to u16

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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 <acme@mandriva.com>
This commit is contained in:
Arnaldo Carvalho de Melo 2006-11-28 00:48:32 -02:00 committed by David S. Miller
parent 5d0dbc4a9b
commit 2ff52f282c
1 changed files with 2 additions and 3 deletions
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5
include/linux/tcp.h
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@ -227,7 +227,8 @@ static inline struct tcp_request_sock *tcp_rsk(const struct request_sock *req)
struct tcp_sock {
/* inet_connection_sock has to be the first member of tcp_sock */
struct inet_connection_sock inet_conn;
int tcp_header_len; /* Bytes of tcp header to send */
u16 tcp_header_len; /* Bytes of tcp header to send */
u16 xmit_size_goal; /* Goal for segmenting output packets */
/*
* Header prediction flags
@ -268,8 +269,6 @@ struct tcp_sock {
__u32 snd_wnd; /* The window we expect to receive */
__u32 max_window; /* Maximal window ever seen from peer */
__u32 mss_cache; /* Cached effective mss, not including SACKS */
__u16 xmit_size_goal; /* Goal for segmenting output packets */
/* XXX Two bytes hole, try to pack */
__u32 window_clamp; /* Maximal window to advertise */
__u32 rcv_ssthresh; /* Current window clamp */