From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH net-next] net: introduce __skb_header_release() Date: Fri, 26 Sep 2014 15:40:21 -0400 (EDT) Message-ID: <20140926.154021.663234155981881132.davem@davemloft.net> References: <1411428572.26859.165.camel@edumazet-glaptop2.roam.corp.google.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org To: eric.dumazet@gmail.com Return-path: Received: from shards.monkeyblade.net ([149.20.54.216]:50391 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755047AbaIZTkX (ORCPT ); Fri, 26 Sep 2014 15:40:23 -0400 In-Reply-To: <1411428572.26859.165.camel@edumazet-glaptop2.roam.corp.google.com> Sender: netdev-owner@vger.kernel.org List-ID: From: Eric Dumazet Date: Mon, 22 Sep 2014 16:29:32 -0700 > From: Eric Dumazet > > While profiling TCP stack, I noticed one useless atomic operation > in tcp_sendmsg(), caused by skb_header_release(). > > It turns out all current skb_header_release() users have a fresh skb, > that no other user can see, so we can avoid one atomic operation. > > Introduce __skb_header_release() to clearly document this. > > This gave me a 1.5 % improvement on TCP_RR workload. > > Signed-off-by: Eric Dumazet Looks great, applied, thanks!