[PATCH] sky2: optimize checksum offload information

Since many packets have the same checksum starting offset and insertion
location; the driver can save the last information and only tell hardware
when it changes.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/net/sky2.h b/drivers/net/sky2.h
index bb92f69..fa8af9f 100644
--- a/drivers/net/sky2.h
+++ b/drivers/net/sky2.h
@@ -1843,6 +1843,8 @@
 	u32		     tx_addr64;
 	u16		     tx_pending;
 	u16		     tx_last_mss;
+	u16		     tx_csum_start;
+	u16		     tx_csum_offset;
 
 	struct ring_info     *rx_ring ____cacheline_aligned_in_smp;
 	struct sky2_rx_le    *rx_le;