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| author | Herbert Xu <herbert@gondor.apana.org.au> | 2009-05-26 18:50:21 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2009-05-27 03:25:55 -0700 |
| commit | 78a478d0efd9e86e5345b436e130497b4e5846e8 (patch) | |
| tree | 273e7565811add8216267f5893335bdb7928a6b7 /include/linux/netdevice.h | |
| parent | 42da6994ca6d20ad1d4e30255dee98047db454e7 (diff) | |
| download | linux-78a478d0efd9e86e5345b436e130497b4e5846e8.tar.gz linux-78a478d0efd9e86e5345b436e130497b4e5846e8.tar.bz2 linux-78a478d0efd9e86e5345b436e130497b4e5846e8.zip | |
gro: Inline skb_gro_header and cache frag0 virtual address
The function skb_gro_header is called four times per packet which
quickly adds up at 10Gb/s. This patch inlines it to allow better
optimisations.
Some architectures perform multiplication for page_address, which
is done by each skb_gro_header invocation. This patch caches that
value in skb->cb to avoid the unnecessary multiplications.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include/linux/netdevice.h')
| -rw-r--r-- | include/linux/netdevice.h | 22 |
1 files changed, 15 insertions, 7 deletions
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 586b71f0358c..61890ed0bcf2 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -1008,6 +1008,9 @@ void netif_napi_add(struct net_device *dev, struct napi_struct *napi, void netif_napi_del(struct napi_struct *napi); struct napi_gro_cb { + /* Virtual address of skb_shinfo(skb)->frags[0].page + offset. */ + void *frag0; + /* This indicates where we are processing relative to skb->data. */ int data_offset; @@ -1107,9 +1110,9 @@ extern int dev_restart(struct net_device *dev); #ifdef CONFIG_NETPOLL_TRAP extern int netpoll_trap(void); #endif -extern void *skb_gro_header(struct sk_buff *skb, unsigned int hlen); extern int skb_gro_receive(struct sk_buff **head, struct sk_buff *skb); +extern void skb_gro_reset_offset(struct sk_buff *skb); static inline unsigned int skb_gro_offset(const struct sk_buff *skb) { @@ -1126,23 +1129,28 @@ static inline void skb_gro_pull(struct sk_buff *skb, unsigned int len) NAPI_GRO_CB(skb)->data_offset += len; } -static inline void skb_gro_reset_offset(struct sk_buff *skb) +static inline void *skb_gro_header(struct sk_buff *skb, unsigned int hlen) { - NAPI_GRO_CB(skb)->data_offset = 0; + unsigned int offset = skb_gro_offset(skb); + + hlen += offset; + if (!NAPI_GRO_CB(skb)->frag0 || + unlikely(skb_shinfo(skb)->frags[0].size + skb_headlen(skb) < hlen)) + 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) : - page_address(skb_shinfo(skb)->frags[0].page) + - skb_shinfo(skb)->frags[0].page_offset; + NAPI_GRO_CB(skb)->frag0; } static inline void *skb_gro_network_header(struct sk_buff *skb) { return skb_headlen(skb) ? skb_network_header(skb) : - page_address(skb_shinfo(skb)->frags[0].page) + - skb_shinfo(skb)->frags[0].page_offset + skb_network_offset(skb); + NAPI_GRO_CB(skb)->frag0 + skb_network_offset(skb); } static inline int dev_hard_header(struct sk_buff *skb, struct net_device *dev, |