From mboxrd@z Thu Jan 1 00:00:00 1970 From: Herbert Xu Subject: [PATCH 11/14] gro: Open-code final pskb_may_pull Date: Wed, 27 May 2009 14:50:31 +1000 Message-ID: References: <20090527044539.GA32372@gondor.apana.org.au> To: "David S. Miller" , netdev@vger.kernel.org Return-path: Received: from rhun.apana.org.au ([64.62.148.172]:49804 "EHLO arnor.apana.org.au" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752152AbZE0FHp (ORCPT ); Wed, 27 May 2009 01:07:45 -0400 Sender: netdev-owner@vger.kernel.org List-ID: gro: Open-code final pskb_may_pull As we know the only packets which need the final pskb_may_pull are completely non-linear, and have all the required bits in frag0, we can perform a straight memcpy instead of going through pskb_may_pull and doing skb_copy_bits. Signed-off-by: Herbert Xu --- net/core/dev.c | 23 +++++++++++++++++++---- 1 file changed, 19 insertions(+), 4 deletions(-) diff --git a/net/core/dev.c b/net/core/dev.c index 5a81302..ed7513c 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -2449,10 +2449,25 @@ int dev_gro_receive(struct napi_struct *napi, struct sk_buff *skb) ret = GRO_HELD; pull: - if (unlikely(!pskb_may_pull(skb, skb_gro_offset(skb)))) { - if (napi->gro_list == skb) - napi->gro_list = skb->next; - ret = GRO_DROP; + if (skb_headlen(skb) < skb_gro_offset(skb)) { + int grow = skb_gro_offset(skb) - skb_headlen(skb); + + BUG_ON(skb->end - skb->tail < grow); + + memcpy(skb_tail_pointer(skb), NAPI_GRO_CB(skb)->frag0, grow); + + skb->tail += grow; + skb->data_len -= grow; + + skb_shinfo(skb)->frags[0].page_offset += grow; + skb_shinfo(skb)->frags[0].size -= grow; + + if (unlikely(!skb_shinfo(skb)->frags[0].size)) { + put_page(skb_shinfo(skb)->frags[0].page); + memmove(skb_shinfo(skb)->frags, + skb_shinfo(skb)->frags + 1, + --skb_shinfo(skb)->nr_frags); + } } ok: