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>

2 files changed, 12 insertions, 16 deletions

diff --git a/include/linux/if_vlan.h b/include/linux/if_vlan.h
index e1ff5b14310e..7ff9af1d0f05 100644
--- a/include/linux/if_vlan.h
+++ b/include/linux/if_vlan.h
@@ -118,8 +118,7 @@ extern int vlan_hwaccel_do_receive(struct sk_buff *skb);
 extern int vlan_gro_receive(struct napi_struct *napi, struct vlan_group *grp,
                             unsigned int vlan_tci, struct sk_buff *skb);
 extern int vlan_gro_frags(struct napi_struct *napi, struct vlan_group *grp,
-                          unsigned int vlan_tci,
-                          struct napi_gro_fraginfo *info);
+                          unsigned int vlan_tci);
 
 #else
 static inline struct net_device *vlan_dev_real_dev(const struct net_device *dev)
@@ -154,8 +153,7 @@ static inline int vlan_gro_receive(struct napi_struct *napi,
 }
 
 static inline int vlan_gro_frags(struct napi_struct *napi,
-                                 struct vlan_group *grp, unsigned int vlan_tci,
-                                 struct napi_gro_fraginfo *info)
+                                 struct vlan_group *grp, unsigned int vlan_tci)
 {
         return NET_RX_DROP;
 }
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 *);