From 78d3fd0b7de844a6dad56e9620fc9d2271b32ab9 Mon Sep 17 00:00:00 2001
From: Herbert Xu <herbert@gondor.apana.org.au>
Date: Tue, 26 May 2009 18:50:23 +0000
Subject: [PATCH] gro: Only use skb_gro_header for completely non-linear
packets
Currently skb_gro_header is used for packets which put the hardware
header in skb->data with the rest in frags. Since the drivers that
need this optimisation all provide completely non-linear packets,
we can gain extra optimisations by only performing the frag0
optimisation for completely non-linear packets.
In particular, we can simply test frag0 (instead of skb_headlen)
to see whether the optimisation is in force.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
include/linux/netdevice.h | 11 ++++++-----
net/core/dev.c | 3 ++-
2 files changed, 8 insertions(+), 6 deletions(-)
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 61890ed0bcf2..d1afc3b64854 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -1135,22 +1135,23 @@ static inline void *skb_gro_header(struct sk_buff *skb, unsigned int hlen)
hlen += offset;
if (!NAPI_GRO_CB(skb)->frag0 ||
- unlikely(skb_shinfo(skb)->frags[0].size + skb_headlen(skb) < hlen))
+ unlikely(skb_shinfo(skb)->frags[0].size < hlen)) {
+ NAPI_GRO_CB(skb)->frag0 = NULL;
return pskb_may_pull(skb, hlen) ? skb->data + offset : NULL;
+ }
return NAPI_GRO_CB(skb)->frag0 + offset;
}
static inline void *skb_gro_mac_header(struct sk_buff *skb)
{
- return skb_headlen(skb) ? skb_mac_header(skb) :
- NAPI_GRO_CB(skb)->frag0;
+ return NAPI_GRO_CB(skb)->frag0 ?: skb_mac_header(skb);
}
static inline void *skb_gro_network_header(struct sk_buff *skb)
{
- return skb_headlen(skb) ? skb_network_header(skb) :
- NAPI_GRO_CB(skb)->frag0 + skb_network_offset(skb);
+ return (NAPI_GRO_CB(skb)->frag0 ?: skb->data) +
+ skb_network_offset(skb);
}
static inline int dev_hard_header(struct sk_buff *skb, struct net_device *dev,
diff --git a/net/core/dev.c b/net/core/dev.c
index bdb1a738193d..f9d90c56b6f0 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -2510,7 +2510,8 @@ void skb_gro_reset_offset(struct sk_buff *skb)
NAPI_GRO_CB(skb)->data_offset = 0;
NAPI_GRO_CB(skb)->frag0 = NULL;
- if (!skb_headlen(skb) && !PageHighMem(skb_shinfo(skb)->frags[0].page))
+ if (skb->mac_header == skb->tail &&
+ !PageHighMem(skb_shinfo(skb)->frags[0].page))
NAPI_GRO_CB(skb)->frag0 =
page_address(skb_shinfo(skb)->frags[0].page) +
skb_shinfo(skb)->frags[0].page_offset;
--
GitLab