[PATCH 4/14] gro: Only use skb_gro_header for completely non-linear packets
flat view
STALE6346d
From: Herbert Xu <herbert@gondor.apana.org.au>
Date: 2009-05-27 05:07:48
Subsystem:
networking drivers, networking [general], the rest · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
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> --- 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 fcb1cc9..38678bc 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 9b4c8da..07ad237 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c@@ -2507,7 +2507,8 @@ 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;