ipv4: Use 32-bit loads for ID and length in GRO
This patch optimises the IPv4 GRO code by using 32-bit loads
(instead of 16-bit ones) on the ID and length checks in the receive
function.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index 644cc55..5abee4c 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -1248,9 +1248,9 @@
struct iphdr *iph;
unsigned int hlen;
unsigned int off;
+ unsigned int id;
int flush = 1;
int proto;
- int id;
off = skb_gro_offset(skb);
hlen = off + sizeof(*iph);
@@ -1274,9 +1274,9 @@
if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
goto out_unlock;
- flush = ntohs(iph->tot_len) != skb_gro_len(skb) ||
- iph->frag_off != htons(IP_DF);
- id = ntohs(iph->id);
+ id = ntohl(*(u32 *)&iph->id);
+ flush = (u16)((ntohl(*(u32 *)iph) ^ skb_gro_len(skb)) | (id ^ IP_DF));
+ id >>= 16;
for (p = *head; p; p = p->next) {
struct iphdr *iph2;