gro: New frags interface to avoid copying shinfo

It turns out that copying a 16-byte area at ~800k times a second
can be really expensive :) This patch redesigns the frags GRO
interface to avoid copying that area twice.

The two disciples of the frags interface have been converted.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 10 insertions, 12 deletions

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 2e7783f4a755..54db3ebf2193 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -1047,14 +1047,6 @@ struct packet_type {
         struct list_head        list;
 };
 
-struct napi_gro_fraginfo {
-        skb_frag_t frags[MAX_SKB_FRAGS];
-        unsigned int nr_frags;
-        unsigned int ip_summed;
-        unsigned int len;
-        __wsum csum;
-};
-
 #include <linux/interrupt.h>
 #include <linux/notifier.h>
 
@@ -1442,12 +1434,18 @@ extern int		napi_gro_receive(struct napi_struct *napi,
                                          struct sk_buff *skb);
 extern void             napi_reuse_skb(struct napi_struct *napi,
                                        struct sk_buff *skb);
-extern struct sk_buff * napi_fraginfo_skb(struct napi_struct *napi,
-                                          struct napi_gro_fraginfo *info);
+extern struct sk_buff * napi_get_frags(struct napi_struct *napi);
 extern int              napi_frags_finish(struct napi_struct *napi,
                                           struct sk_buff *skb, int ret);
-extern int              napi_gro_frags(struct napi_struct *napi,
-                                       struct napi_gro_fraginfo *info);
+extern struct sk_buff * napi_frags_skb(struct napi_struct *napi);
+extern int              napi_gro_frags(struct napi_struct *napi);
+
+static inline void napi_free_frags(struct napi_struct *napi)
+{
+        kfree_skb(napi->skb);
+        napi->skb = NULL;
+}
+
 extern void             netif_nit_deliver(struct sk_buff *skb);
 extern int              dev_valid_name(const char *name);
 extern int              dev_ioctl(struct net *net, unsigned int cmd, void __user *);