From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751312AbdGQCWu (ORCPT ); Sun, 16 Jul 2017 22:22:50 -0400 Received: from mail-pg0-f67.google.com ([74.125.83.67]:34690 "EHLO mail-pg0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751245AbdGQCWs (ORCPT ); Sun, 16 Jul 2017 22:22:48 -0400 From: Lin Zhang To: davem@davemloft.net Cc: linux-kernel@vger.kernel.org, netdev@vger.kernel.org, Lin Zhang Subject: [PATCH net-next resubmit] skbuff: optimize the pull_pages code in __pskb_pull_tail() Date: Mon, 17 Jul 2017 10:22:06 +0800 Message-Id: <1500258126-11235-1-git-send-email-xiaolou4617@gmail.com> X-Mailer: git-send-email 1.8.3.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In the pull_pages code block, if the first frag size > eat, we can end the loop in advance to avoid extra copy. Signed-off-by: Lin Zhang --- net/core/skbuff.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/net/core/skbuff.c b/net/core/skbuff.c index f990eb8..c00a1df 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -1720,6 +1720,10 @@ void *__pskb_pull_tail(struct sk_buff *skb, int delta) skb_shinfo(skb)->frags[k].page_offset += eat; skb_frag_size_sub(&skb_shinfo(skb)->frags[k], eat); eat = 0; + if (!i) { + k = skb_shinfo(skb)->nr_frags; + break; + } } k++; } -- 1.8.3.1