On Mon, 15 Nov 2010, Eric Dumazet wrote:
> Le dimanche 14 novembre 2010 à 22:47 +0100, Jesper Juhl a écrit :
> > By adding two pointer variables to
> > net/ipv6/netfilter/ip6t_LOG.c::dump_packet() we can save 19 bytes of .text
> > and many pointer dereferences.
> >
> > before:
> > text data bss dec hex filename
> > 6258 600 3088 9946 26da net/ipv6/netfilter/ip6t_LOG.o
> >
> > after:
> > text data bss dec hex filename
> > 6239 600 3088 9927 26c7 net/ipv6/netfilter/ip6t_LOG.o
> >
> >
> > Please Cc me on replies.
> >
> >
> > Signed-off-by: Jesper Juhl <jj@xxxxxxxxxxxxx>
> > ---
> > ip6t_LOG.c | 16 ++++++++++------
> > 1 file changed, 10 insertions(+), 6 deletions(-)
> >
> > diff --git a/net/ipv6/netfilter/ip6t_LOG.c b/net/ipv6/netfilter/ip6t_LOG.c
> > index 09c8889..51d10a5 100644
> > --- a/net/ipv6/netfilter/ip6t_LOG.c
> > +++ b/net/ipv6/netfilter/ip6t_LOG.c
[...]
>
> Same comment than previous patch, you add a NULL dereference.
>
Hopefully this is beter (same as change done to the other (ipv4) patch).
Fewer pointer derefs and smaller .text size for
net/ipv4/netfilter/ipt_LOG.c::dump_packet()
Signed-off-by: Jesper Juhl <jj@xxxxxxxxxxxxx>
---
ip6t_LOG.c | 12 +++++++-----
1 file changed, 7 insertions(+), 5 deletions(-)
diff --git a/net/ipv6/netfilter/ip6t_LOG.c b/net/ipv6/netfilter/ip6t_LOG.c
index 09c8889..de15b14 100644
--- a/net/ipv6/netfilter/ip6t_LOG.c
+++ b/net/ipv6/netfilter/ip6t_LOG.c
@@ -46,6 +46,7 @@ static void dump_packet(struct sbuff *m,
unsigned int ptr;
unsigned int hdrlen = 0;
unsigned int logflags;
+ struct sock *sk;
if (info->type == NF_LOG_TYPE_LOG)
logflags = info->u.log.logflags;
@@ -359,12 +360,13 @@ static void dump_packet(struct sbuff *m,
/* Max length: 15 "UID=4294967295 " */
if ((logflags & IP6T_LOG_UID) && recurse && skb->sk) {
- read_lock_bh(&skb->sk->sk_callback_lock);
- if (skb->sk->sk_socket && skb->sk->sk_socket->file)
+ sk = skb->sk;
+ read_lock_bh(&sk->sk_callback_lock);
+ if (sk->sk_socket && sk->sk_socket->file)
sb_add(m, "UID=%u GID=%u ",
- skb->sk->sk_socket->file->f_cred->fsuid,
- skb->sk->sk_socket->file->f_cred->fsgid);
- read_unlock_bh(&skb->sk->sk_callback_lock);
+ sk->sk_socket->file->f_cred->fsuid,
+ sk->sk_socket->file->f_cred->fsgid);
+ read_unlock_bh(&sk->sk_callback_lock);
}
/* Max length: 16 "MARK=0xFFFFFFFF " */
--
Jesper Juhl <jj@xxxxxxxxxxxxx> http://www.chaosbits.net/
Don't top-post http://www.catb.org/~esr/jargon/html/T/top-post.html
Plain text mails only, please.
