summaryrefslogtreecommitdiffstats
path: root/net/ipv4
diff options
context:
space:
mode:
authorHerbert Xu <herbert@gondor.apana.org.au>2009-05-26 18:50:28 +0000
committerDavid S. Miller <davem@davemloft.net>2009-05-27 03:26:01 -0700
commita5b1cf288d4200506ab62fbb86cc81ace948a306 (patch)
treec95339866f4d67220d111811a92e5c6b79de6ab4 /net/ipv4
parent7489594cb249aeb178287c9a43a9e4f366044259 (diff)
downloadlinux-stable-a5b1cf288d4200506ab62fbb86cc81ace948a306.tar.gz
linux-stable-a5b1cf288d4200506ab62fbb86cc81ace948a306.tar.bz2
linux-stable-a5b1cf288d4200506ab62fbb86cc81ace948a306.zip
gro: Avoid unnecessary comparison after skb_gro_header
For the overwhelming majority of cases, skb_gro_header's return value cannot be NULL. Yet we must check it because of its current form. This patch splits it up into multiple functions in order to avoid this. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4')
-rw-r--r--net/ipv4/af_inet.c13
-rw-r--r--net/ipv4/tcp.c22
2 files changed, 26 insertions, 9 deletions
diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index 170689681aa2..644cc5535319 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -1246,13 +1246,20 @@ static struct sk_buff **inet_gro_receive(struct sk_buff **head,
struct sk_buff **pp = NULL;
struct sk_buff *p;
struct iphdr *iph;
+ unsigned int hlen;
+ unsigned int off;
int flush = 1;
int proto;
int id;
- iph = skb_gro_header(skb, sizeof(*iph));
- if (unlikely(!iph))
- goto out;
+ off = skb_gro_offset(skb);
+ hlen = off + sizeof(*iph);
+ iph = skb_gro_header_fast(skb, off);
+ if (skb_gro_header_hard(skb, hlen)) {
+ iph = skb_gro_header_slow(skb, hlen, off);
+ if (unlikely(!iph))
+ goto out;
+ }
proto = iph->protocol & (MAX_INET_PROTOS - 1);
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 68342d431896..c3dcec5efea5 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -2518,20 +2518,30 @@ struct sk_buff **tcp_gro_receive(struct sk_buff **head, struct sk_buff *skb)
unsigned int thlen;
unsigned int flags;
unsigned int mss = 1;
+ unsigned int hlen;
+ unsigned int off;
int flush = 1;
int i;
- th = skb_gro_header(skb, sizeof(*th));
- if (unlikely(!th))
- goto out;
+ off = skb_gro_offset(skb);
+ hlen = off + sizeof(*th);
+ th = skb_gro_header_fast(skb, off);
+ if (skb_gro_header_hard(skb, hlen)) {
+ th = skb_gro_header_slow(skb, hlen, off);
+ if (unlikely(!th))
+ goto out;
+ }
thlen = th->doff * 4;
if (thlen < sizeof(*th))
goto out;
- th = skb_gro_header(skb, thlen);
- if (unlikely(!th))
- goto out;
+ hlen = off + thlen;
+ if (skb_gro_header_hard(skb, hlen)) {
+ th = skb_gro_header_slow(skb, hlen, off);
+ if (unlikely(!th))
+ goto out;
+ }
skb_gro_pull(skb, thlen);