diff options
| author | Eric Dumazet <edumazet@google.com> | 2012-07-04 22:30:09 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2012-07-05 03:03:32 -0700 |
| commit | bf5e53e3717ed28be69d0663c65962d1731e7ee4 (patch) | |
| tree | 7211c0114426ece185d27e3d7c637ecf354fba72 /net | |
| parent | 36bdbcae2fa2a6dfa99344d4190fcea0aa7b7c25 (diff) | |
ipv4: defer fib_compute_spec_dst() call
ip_options_compile() can avoid calling fib_compute_spec_dst()
by default, and perform the call only if needed.
David suggested to add a helper to make the call only once.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
| -rw-r--r-- | net/ipv4/ip_options.c | 15 |
1 files changed, 12 insertions, 3 deletions
diff --git a/net/ipv4/ip_options.c b/net/ipv4/ip_options.c index 1f022510abe3..a19d6471a318 100644 --- a/net/ipv4/ip_options.c +++ b/net/ipv4/ip_options.c @@ -242,6 +242,15 @@ void ip_options_fragment(struct sk_buff *skb) opt->ts_needtime = 0; } +/* helper used by ip_options_compile() to call fib_compute_spec_dst() + * at most one time. + */ +static void spec_dst_fill(__be32 *spec_dst, struct sk_buff *skb) +{ + if (*spec_dst == htonl(INADDR_ANY)) + *spec_dst = fib_compute_spec_dst(skb); +} + /* * Verify options and fill pointers in struct options. * Caller should clear *opt, and set opt->data. @@ -251,7 +260,7 @@ void ip_options_fragment(struct sk_buff *skb) int ip_options_compile(struct net *net, struct ip_options *opt, struct sk_buff *skb) { - __be32 spec_dst = (__force __be32) 0; + __be32 spec_dst = htonl(INADDR_ANY); unsigned char *pp_ptr = NULL; struct rtable *rt = NULL; unsigned char *optptr; @@ -260,8 +269,6 @@ int ip_options_compile(struct net *net, if (skb != NULL) { rt = skb_rtable(skb); - if (rt) - spec_dst = fib_compute_spec_dst(skb); optptr = (unsigned char *)&(ip_hdr(skb)[1]); } else optptr = opt->__data; @@ -334,6 +341,7 @@ int ip_options_compile(struct net *net, goto error; } if (rt) { + spec_dst_fill(&spec_dst, skb); memcpy(&optptr[optptr[2]-1], &spec_dst, 4); opt->is_changed = 1; } @@ -376,6 +384,7 @@ int ip_options_compile(struct net *net, } opt->ts = optptr - iph; if (rt) { + spec_dst_fill(&spec_dst, skb); memcpy(&optptr[optptr[2]-1], &spec_dst, 4); timeptr = &optptr[optptr[2]+3]; } |