In order to reduce the size of struct skbuff use 16 bit integer
offsets rather than pointers for inner_*_headers.
The implication of this is that the behaviour of
is that of other _headers when NET_SKBUFF_DATA_USES_OFFSET is set.
This appears to reduce the size of struct skbuff from 0xd0 to 0xc8
bytes on x86_64 with the following all unset.
CONFIG_XFRM
CONFIG_NF_CONNTRACK
CONFIG_NF_CONNTRACK_MODULE
NET_SKBUFF_NF_DEFRAG_NEEDED
CONFIG_BRIDGE_NETFILTER
CONFIG_NET_SCHED
CONFIG_IPV6_NDISC_NODETYPE
CONFIG_NET_DMA
CONFIG_NETWORK_SECMARK
Signed-off-by: Simon Horman <ho...@verge.net.au>
---
include/linux/skbuff.h | 63 +++++++-------------------------------------------
1 file changed, 8 insertions(+), 55 deletions(-)
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 2e0ced1..3791615 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -509,9 +509,9 @@ struct sk_buff {
__u32 reserved_tailroom;
};
- sk_buff_data_t inner_transport_header;
- sk_buff_data_t inner_network_header;
- sk_buff_data_t inner_mac_header;
+ __u16 inner_transport_header;
+ __u16 inner_network_header;
+ __u16 inner_mac_header;
sk_buff_data_t transport_header;
sk_buff_data_t network_header;
sk_buff_data_t mac_header;
@@ -1517,9 +1517,9 @@ static inline void skb_reserve(struct sk_buff *skb, int
len)
static inline void skb_reset_inner_headers(struct sk_buff *skb)
{
- skb->inner_mac_header = skb->mac_header;
- skb->inner_network_header = skb->network_header;
- skb->inner_transport_header = skb->transport_header;
+ skb->inner_mac_header = 0;
+ skb->inner_network_header = 0;
+ skb->inner_transport_header = 0;
}
static inline void skb_reset_mac_len(struct sk_buff *skb)
@@ -1527,7 +1527,6 @@ static inline void skb_reset_mac_len(struct sk_buff *skb)
skb->mac_len = skb->network_header - skb->mac_header;
}
-#ifdef NET_SKBUFF_DATA_USES_OFFSET
static inline unsigned char *skb_inner_transport_header(const struct sk_buff
*skb)
{
@@ -1579,6 +1578,8 @@ static inline void skb_set_inner_mac_header(struct
sk_buff *skb,
skb_reset_inner_mac_header(skb);
skb->inner_mac_header += offset;
}
+
+#ifdef NET_SKBUFF_DATA_USES_OFFSET
static inline bool skb_transport_header_was_set(const struct sk_buff *skb)
{
return skb->transport_header != ~0U;
@@ -1639,54 +1640,6 @@ static inline void skb_set_mac_header(struct sk_buff
*skb, const int offset)
}
#else /* NET_SKBUFF_DATA_USES_OFFSET */
-static inline unsigned char *skb_inner_transport_header(const struct sk_buff
- *skb)
-{
- return skb->inner_transport_header;
-}
-
-static inline void skb_reset_inner_transport_header(struct sk_buff *skb)
-{
- skb->inner_transport_header = skb->data;
-}
-
-static inline void skb_set_inner_transport_header(struct sk_buff *skb,
- const int offset)
-{
- skb->inner_transport_header = skb->data + offset;
-}
-
-static inline unsigned char *skb_inner_network_header(const struct sk_buff
*skb)
-{
- return skb->inner_network_header;
-}
-
-static inline void skb_reset_inner_network_header(struct sk_buff *skb)
-{
- skb->inner_network_header = skb->data;
-}
-
-static inline void skb_set_inner_network_header(struct sk_buff *skb,
- const int offset)
-{
- skb->inner_network_header = skb->data + offset;
-}
-
-static inline unsigned char *skb_inner_mac_header(const struct sk_buff *skb)
-{
- return skb->inner_mac_header;
-}
-
-static inline void skb_reset_inner_mac_header(struct sk_buff *skb)
-{
- skb->inner_mac_header = skb->data;
-}
-
-static inline void skb_set_inner_mac_header(struct sk_buff *skb,
- const int offset)
-{
- skb->inner_mac_header = skb->data + offset;
-}
static inline bool skb_transport_header_was_set(const struct sk_buff *skb)
{
return skb->transport_header != NULL;
--
1.8.2.1
_______________________________________________
dev mailing list
dev@openvswitch.org
http://openvswitch.org/mailman/listinfo/dev
