From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mailhub1.si.c-s.fr (pegase1.c-s.fr [93.17.236.30]) by lists.ozlabs.org (Postfix) with ESMTP id 774C51A0CA8 for ; Mon, 29 Feb 2016 18:26:02 +1100 (AEDT) From: Christophe Leroy Subject: Re: [PATCH 4/9] powerpc: inline ip_fast_csum() To: Denis Kirjanov References: <807dbc9449077e36752c649c09ae1c0d70e45254.1442876807.git.christophe.leroy@c-s.fr> Cc: Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , scottwood@freescale.com, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, netdev@vger.kernel.org Message-ID: <56D3F287.6020707@c-s.fr> Date: Mon, 29 Feb 2016 08:25:59 +0100 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Le 23/09/2015 07:43, Denis Kirjanov a écrit : > On 9/22/15, Christophe Leroy wrote: >> In several architectures, ip_fast_csum() is inlined >> There are functions like ip_send_check() which do nothing >> much more than calling ip_fast_csum(). >> Inlining ip_fast_csum() allows the compiler to optimise better > Hi Christophe, > I did try it and see no difference on ppc64. Did you test with socklib > with modified loopback and if so do you have any numbers? Hi Denis, I put a mftbl at start and end of ip_send_check() and tested on a MPC885: * Without ip_fast_csum() inlined, approxymatly 7 TB ticks are spent in ip_send_check() * With ip_fast_csum() inlined, approxymatly 5,4 TB ticks are spent in ip_send_check() So it is about 23% time reduction. Christophe