[PATCH 1/6] net: pack skb_shared_info more efficiently
From: Ian Campbell <hidden>
Date: 2012-01-05 17:13:49
Subsystem:
networking [general], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
nr_frags can be 8 bits since 256 is plenty of fragments. This allows it to be packed with tx_flags. Also by moving ip6_frag_id and dataref (both 4 bytes) next to each other we can avoid a hole between ip6_frag_id and frag_list on 64 bit systems. Signed-off-by: Ian Campbell <redacted> --- include/linux/skbuff.h | 6 +++--- 1 files changed, 3 insertions(+), 3 deletions(-)
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index f47f0c3..50db9b0 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h@@ -242,15 +242,15 @@ struct ubuf_info { * the end of the header data, ie. at skb->end. */ struct skb_shared_info { - unsigned short nr_frags; + unsigned char nr_frags; + __u8 tx_flags; unsigned short gso_size; /* Warning: this field is not always filled in (UFO)! */ unsigned short gso_segs; unsigned short gso_type; - __be32 ip6_frag_id; - __u8 tx_flags; struct sk_buff *frag_list; struct skb_shared_hwtstamps hwtstamps; + __be32 ip6_frag_id; /* * Warning : all fields before dataref are cleared in __alloc_skb()
--
1.7.2.5