From d7e8883cfcf4851afe74fb380cc62b7fa9cf66ba Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Mon, 30 Apr 2012 08:10:34 +0000 Subject: net: make GRO aware of skb->head_frag MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit GRO can check if skb to be merged has its skb->head mapped to a page fragment, instead of a kmalloc() area. We 'upgrade' skb->head as a fragment in itself This avoids the frag_list fallback, and permits to build true GRO skb (one sk_buff and up to 16 fragments), using less memory. This reduces number of cache misses when user makes its copy, since a single sk_buff is fetched. This is a followup of patch "net: allow skb->head to be a page fragment" Signed-off-by: Eric Dumazet Cc: Ilpo Järvinen Cc: Herbert Xu Cc: Maciej Żenczykowski Cc: Neal Cardwell Cc: Tom Herbert Cc: Jeff Kirsher Cc: Ben Hutchings Cc: Matt Carlson Cc: Michael Chan Signed-off-by: David S. Miller --- net/core/dev.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'net/core/dev.c') diff --git a/net/core/dev.c b/net/core/dev.c index 501f3cc703dd..a2be59fe6ab8 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -3546,7 +3546,10 @@ gro_result_t napi_skb_finish(gro_result_t ret, struct sk_buff *skb) break; case GRO_MERGED_FREE: - consume_skb(skb); + if (NAPI_GRO_CB(skb)->free == NAPI_GRO_FREE_STOLEN_HEAD) + kmem_cache_free(skbuff_head_cache, skb); + else + __kfree_skb(skb); break; case GRO_HELD: -- cgit v1.2.3