net: Add priority to packet_offload objects.

When we scan a packet for GRO processing, we want to see the most
common packet types in the front of the offload_base list.

So add a priority field so we can handle this properly.

IPv4/IPv6 get the highest priority with the implicit zero priority
field.

Next comes ethernet with a priority of 10, and then we have the MPLS
types with a priority of 15.

Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Suggested-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 51f8d2f..6f5f71f 100644 (file)
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -1997,6 +1997,7 @@ struct offload_callbacks {
 
 struct packet_offload {
        __be16                   type;  /* This is really htons(ether_type). */
+       u16                      priority;
        struct offload_callbacks callbacks;
        struct list_head         list;
 };

diff --git a/net/core/dev.c b/net/core/dev.c
index 594163d..0602e91 100644 (file)
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -469,10 +469,14 @@ EXPORT_SYMBOL(dev_remove_pack);
  */
 void dev_add_offload(struct packet_offload *po)
 {
-       struct list_head *head = &offload_base;
+       struct packet_offload *elem;
 
        spin_lock(&offload_lock);
-       list_add_rcu(&po->list, head);
+       list_for_each_entry(elem, &offload_base, list) {
+               if (po->priority < elem->priority)
+                       break;
+       }
+       list_add_rcu(&po->list, elem->list.prev);
        spin_unlock(&offload_lock);
 }
 EXPORT_SYMBOL(dev_add_offload);

diff --git a/net/ethernet/eth.c b/net/ethernet/eth.c
index c3325bd..7d0e239 100644 (file)
--- a/net/ethernet/eth.c
+++ b/net/ethernet/eth.c
@@ -470,6 +470,7 @@ EXPORT_SYMBOL(eth_gro_complete);
 
 static struct packet_offload eth_packet_offload __read_mostly = {
        .type = cpu_to_be16(ETH_P_TEB),
+       .priority = 10,
        .callbacks = {
                .gro_receive = eth_gro_receive,
                .gro_complete = eth_gro_complete,

diff --git a/net/mpls/mpls_gso.c b/net/mpls/mpls_gso.c
index 809df53..0183b32 100644 (file)
--- a/net/mpls/mpls_gso.c
+++ b/net/mpls/mpls_gso.c
@@ -62,6 +62,7 @@ out:
 
 static struct packet_offload mpls_mc_offload __read_mostly = {
        .type = cpu_to_be16(ETH_P_MPLS_MC),
+       .priority = 15,
        .callbacks = {
                .gso_segment    =       mpls_gso_segment,
        },
@@ -69,6 +70,7 @@ static struct packet_offload mpls_mc_offload __read_mostly = {
 
 static struct packet_offload mpls_uc_offload __read_mostly = {
        .type = cpu_to_be16(ETH_P_MPLS_UC),
+       .priority = 15,
        .callbacks = {
                .gso_segment    =       mpls_gso_segment,
        },