From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D21BDC33CAD for ; Mon, 13 Jan 2020 12:51:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A72802084D for ; Mon, 13 Jan 2020 12:51:50 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=wp.pl header.i=@wp.pl header.b="rUht59dH" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728773AbgAMMvt (ORCPT ); Mon, 13 Jan 2020 07:51:49 -0500 Received: from mx4.wp.pl ([212.77.101.12]:45366 "EHLO mx4.wp.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726480AbgAMMvt (ORCPT ); Mon, 13 Jan 2020 07:51:49 -0500 Received: (wp-smtpd smtp.wp.pl 17450 invoked from network); 13 Jan 2020 13:51:46 +0100 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=wp.pl; s=1024a; t=1578919906; bh=Mxm7b8zM02QFZaaphROEcKcn/YEx9WXTuE/NQeKUMUs=; h=From:To:Cc:Subject; b=rUht59dHg4E9WOMTiWla3X+3rKCaD7tAd0PX3Ue1TBpJntMZkghkbgqQgvWXcoV3i Y3oZ3nPg2I1dfYthFTDcGv0gGLDOqhs7ZG3yrNS8xidHYGyWTd9xVUU2ndHKNQkDv9 cZ39RH3qFpGHmV0OcbokFoBLxDh2D5cypZWD04MY= Received: from c-73-93-4-247.hsd1.ca.comcast.net (HELO cakuba) (kubakici@wp.pl@[73.93.4.247]) (envelope-sender ) by smtp.wp.pl (WP-SMTPD) with ECDHE-RSA-AES256-GCM-SHA384 encrypted SMTP for ; 13 Jan 2020 13:51:46 +0100 Date: Mon, 13 Jan 2020 04:51:36 -0800 From: Jakub Kicinski To: Niu Xilei Cc: davem@davemloft.net, tglx@linutronix.de, fw@strlen.de, peterz@infradead.org, steffen.klassert@secunet.com, bigeasy@linutronix.de, jonathan.lemon@gmail.com, pabeni@redhat.com, anshuman.khandual@arm.com, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2] pktgen: create packet use IPv6 source address between src6_min and src6_max. Message-ID: <20200113045136.4d59dded@cakuba> In-Reply-To: <20200113112103.6766-1-niu_xilei@163.com> References: <20200113112103.6766-1-niu_xilei@163.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-WP-MailID: b6ed76e7110333e816cd291da4871436 X-WP-AV: skaner antywirusowy Poczty Wirtualnej Polski X-WP-SPAM: NO 0000000 [oWMU] Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org The subject line could use some rewording, I think. On Mon, 13 Jan 2020 19:21:02 +0800, Niu Xilei wrote: > Pktgen can use only one IPv6 source address from output device, or src6 command > setting. In pressure test we need create lots of session more than 65536.If > IPSRC_RND flag is set, generate random source address between src6_min and src6_max. > > Signed-off-by: Niu Xilei > > Changes since v1: > - only create IPv6 source address over least significant 64 bit range > +/* generate ipv6 source addr */ > +static inline void set_src_in6_addr(struct pktgen_dev *pkt_dev) Please just use "static" instead of "static inline". The compiler will be clever enough to decide the inlining. > +{ > + __be64 min6_h, min6_l, max6_h, max6_l, addr_l, *t; > + u64 min6, max6, rand, i; > + struct in6_addr addr6; > + > + memcpy(&min6_h, pkt_dev->min_in6_saddr.s6_addr, 8); > + memcpy(&min6_l, pkt_dev->min_in6_saddr.s6_addr + 8, 8); > + memcpy(&max6_h, pkt_dev->max_in6_saddr.s6_addr, 8); > + memcpy(&max6_l, pkt_dev->max_in6_saddr.s6_addr + 8, 8); > + > + /* only generate source address in least significant 64 bits range > + * most significant 64 bits must be equal > + */ > + if (max6_h != min6_h) > + return; > + > + addr6 = pkt_dev->min_in6_saddr; > + t = (__be64 *)addr6.s6_addr + 1; > + min6 = be64_to_cpu(min6_l); > + max6 = be64_to_cpu(max6_l); > + > + if (min6 < max6) { Since this code is executed on every packet, would it be possible to pre-compute the decision if the IPv6 address is to be generated or not? We have 4 memcpy()s and 2 byte swaps, and the conditions never change, so it could be computed at setup time, right? > + if (pkt_dev->flags & F_IPSRC_RND) { > + do { > + prandom_bytes(&rand, sizeof(rand)); > + rand = rand % (max6 - min6) + min6; > + addr_l = cpu_to_be64(rand); > + memcpy(t, &addr_l, 8); > + } while (ipv6_addr_loopback(&addr6) || > + ipv6_addr_v4mapped(&addr6) || > + ipv6_addr_is_multicast(&addr6)); > + } else { > + addr6 = pkt_dev->cur_in6_saddr; > + i = be64_to_cpu(*t); > + if (++i > max6) > + i = min6; > + addr_l = cpu_to_be64(i); > + memcpy(t, &addr_l, 8); > + } > + } > + pkt_dev->cur_in6_saddr = addr6; > +}