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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BD44AC3F6B0 for ; Wed, 10 Aug 2022 14:41:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232644AbiHJOlg (ORCPT ); Wed, 10 Aug 2022 10:41:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52656 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232684AbiHJOlR (ORCPT ); Wed, 10 Aug 2022 10:41:17 -0400 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8A58C4F695 for ; Wed, 10 Aug 2022 07:41:07 -0700 (PDT) Received: from dggpeml500022.china.huawei.com (unknown [172.30.72.57]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4M2syC3yTfzmVPP; Wed, 10 Aug 2022 22:38:59 +0800 (CST) Received: from [10.67.103.87] (10.67.103.87) by dggpeml500022.china.huawei.com (7.185.36.66) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Wed, 10 Aug 2022 22:41:03 +0800 Subject: Re: [RFCv7 PATCH net-next 23/36] net: adjust the build check for net_gso_ok() To: Alexander Lobakin CC: , , , , , , , , References: <20220810030624.34711-1-shenjian15@huawei.com> <20220810030624.34711-24-shenjian15@huawei.com> <20220810110917.1307697-1-alexandr.lobakin@intel.com> From: "shenjian (K)" Message-ID: Date: Wed, 10 Aug 2022 22:41:03 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.5.2 MIME-Version: 1.0 In-Reply-To: <20220810110917.1307697-1-alexandr.lobakin@intel.com> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 8bit X-Originating-IP: [10.67.103.87] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To dggpeml500022.china.huawei.com (7.185.36.66) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org 在 2022/8/10 19:09, Alexander Lobakin 写道: > From: Jian Shen > Date: Wed, 10 Aug 2022 11:06:11 +0800 > >> Introduce macro GSO_INDEX(x) to replace the NETIF_F_XXX >> feature shift check, for all the macroes NETIF_F_XXX will >> be remove later. >> >> Signed-off-by: Jian Shen >> --- >> include/linux/netdevice.h | 40 ++++++++++++++++++++------------------- >> 1 file changed, 21 insertions(+), 19 deletions(-) >> >> diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h >> index 1bd5dcbc884d..b01af2a3838d 100644 >> --- a/include/linux/netdevice.h >> +++ b/include/linux/netdevice.h >> @@ -4886,28 +4886,30 @@ netdev_features_t netif_skb_features(struct sk_buff *skb); >> >> static inline bool net_gso_ok(netdev_features_t features, int gso_type) >> { >> +#define GSO_INDEX(x) ((1ULL << (x)) >> NETIF_F_GSO_SHIFT) > What if we get a new GSO offload which's corresponding bit will be > higher than 64? > You could instead do > > #define __SKB_GSO_FLAG(x) (1ULL << (x)) > > enum { > SKB_GSO_TCPV4_BIT = 0, > SKB_GSO_DODGY_BIT = 1, > ..., > }; > enum { > SKB_GSO_TCPV4 = __SKB_GSO_FLAG(TCPV4), > SKB_GSO_DODGY = __SKB_GSO_FLAG(DODGY), > ..., > }; > > and then just > > #define ASSERT_GSO_TYPE(fl, feat) \ > static_assert((fl) == (feat) - NETIF_F_GSO_SHIFT) > > ... > ASSERT_GSO_TYPE(SKB_GSO_TCPV4_BIT, NETIF_F_TSO_BIT); > ASSERT_GSO_TYPE(SKB_GSO_DODGY, NETIF_F_GSO_ROBUST_BIT); > ... Yes, it may be misused for new GSO offload bit higher than 64, the macro __SKB_GSO_FLAG(x) is better. >> + >> netdev_features_t feature = (netdev_features_t)gso_type << NETIF_F_GSO_SHIFT; >> >> /* check flags correspondence */ >> - BUILD_BUG_ON(SKB_GSO_TCPV4 != (NETIF_F_TSO >> NETIF_F_GSO_SHIFT)); >> - BUILD_BUG_ON(SKB_GSO_DODGY != (NETIF_F_GSO_ROBUST >> NETIF_F_GSO_SHIFT)); >> - BUILD_BUG_ON(SKB_GSO_TCP_ECN != (NETIF_F_TSO_ECN >> NETIF_F_GSO_SHIFT)); >> - BUILD_BUG_ON(SKB_GSO_TCP_FIXEDID != (NETIF_F_TSO_MANGLEID >> NETIF_F_GSO_SHIFT)); >> - BUILD_BUG_ON(SKB_GSO_TCPV6 != (NETIF_F_TSO6 >> NETIF_F_GSO_SHIFT)); >> - BUILD_BUG_ON(SKB_GSO_FCOE != (NETIF_F_FSO >> NETIF_F_GSO_SHIFT)); >> - BUILD_BUG_ON(SKB_GSO_GRE != (NETIF_F_GSO_GRE >> NETIF_F_GSO_SHIFT)); >> - BUILD_BUG_ON(SKB_GSO_GRE_CSUM != (NETIF_F_GSO_GRE_CSUM >> NETIF_F_GSO_SHIFT)); >> - BUILD_BUG_ON(SKB_GSO_IPXIP4 != (NETIF_F_GSO_IPXIP4 >> NETIF_F_GSO_SHIFT)); >> - BUILD_BUG_ON(SKB_GSO_IPXIP6 != (NETIF_F_GSO_IPXIP6 >> NETIF_F_GSO_SHIFT)); >> - BUILD_BUG_ON(SKB_GSO_UDP_TUNNEL != (NETIF_F_GSO_UDP_TUNNEL >> NETIF_F_GSO_SHIFT)); >> - BUILD_BUG_ON(SKB_GSO_UDP_TUNNEL_CSUM != (NETIF_F_GSO_UDP_TUNNEL_CSUM >> NETIF_F_GSO_SHIFT)); >> - BUILD_BUG_ON(SKB_GSO_PARTIAL != (NETIF_F_GSO_PARTIAL >> NETIF_F_GSO_SHIFT)); >> - BUILD_BUG_ON(SKB_GSO_TUNNEL_REMCSUM != (NETIF_F_GSO_TUNNEL_REMCSUM >> NETIF_F_GSO_SHIFT)); >> - BUILD_BUG_ON(SKB_GSO_SCTP != (NETIF_F_GSO_SCTP >> NETIF_F_GSO_SHIFT)); >> - BUILD_BUG_ON(SKB_GSO_ESP != (NETIF_F_GSO_ESP >> NETIF_F_GSO_SHIFT)); >> - BUILD_BUG_ON(SKB_GSO_UDP != (NETIF_F_GSO_UDP >> NETIF_F_GSO_SHIFT)); >> - BUILD_BUG_ON(SKB_GSO_UDP_L4 != (NETIF_F_GSO_UDP_L4 >> NETIF_F_GSO_SHIFT)); >> - BUILD_BUG_ON(SKB_GSO_FRAGLIST != (NETIF_F_GSO_FRAGLIST >> NETIF_F_GSO_SHIFT)); >> + BUILD_BUG_ON(SKB_GSO_TCPV4 != GSO_INDEX(NETIF_F_TSO_BIT)); >> + BUILD_BUG_ON(SKB_GSO_DODGY != GSO_INDEX(NETIF_F_GSO_ROBUST_BIT)); >> + BUILD_BUG_ON(SKB_GSO_TCP_ECN != GSO_INDEX(NETIF_F_TSO_ECN_BIT)); >> + BUILD_BUG_ON(SKB_GSO_TCP_FIXEDID != GSO_INDEX(NETIF_F_TSO_MANGLEID_BIT)); >> + BUILD_BUG_ON(SKB_GSO_TCPV6 != GSO_INDEX(NETIF_F_TSO6_BIT)); >> + BUILD_BUG_ON(SKB_GSO_FCOE != GSO_INDEX(NETIF_F_FSO_BIT)); >> + BUILD_BUG_ON(SKB_GSO_GRE != GSO_INDEX(NETIF_F_GSO_GRE_BIT)); >> + BUILD_BUG_ON(SKB_GSO_GRE_CSUM != GSO_INDEX(NETIF_F_GSO_GRE_CSUM_BIT)); >> + BUILD_BUG_ON(SKB_GSO_IPXIP4 != GSO_INDEX(NETIF_F_GSO_IPXIP4_BIT)); >> + BUILD_BUG_ON(SKB_GSO_IPXIP6 != GSO_INDEX(NETIF_F_GSO_IPXIP6_BIT)); >> + BUILD_BUG_ON(SKB_GSO_UDP_TUNNEL != GSO_INDEX(NETIF_F_GSO_UDP_TUNNEL_BIT)); >> + BUILD_BUG_ON(SKB_GSO_UDP_TUNNEL_CSUM != GSO_INDEX(NETIF_F_GSO_UDP_TUNNEL_CSUM_BIT)); >> + BUILD_BUG_ON(SKB_GSO_PARTIAL != GSO_INDEX(NETIF_F_GSO_PARTIAL_BIT)); >> + BUILD_BUG_ON(SKB_GSO_TUNNEL_REMCSUM != GSO_INDEX(NETIF_F_GSO_TUNNEL_REMCSUM_BIT)); >> + BUILD_BUG_ON(SKB_GSO_SCTP != GSO_INDEX(NETIF_F_GSO_SCTP_BIT)); >> + BUILD_BUG_ON(SKB_GSO_ESP != GSO_INDEX(NETIF_F_GSO_ESP_BIT)); >> + BUILD_BUG_ON(SKB_GSO_UDP != GSO_INDEX(NETIF_F_GSO_UDP_BIT)); >> + BUILD_BUG_ON(SKB_GSO_UDP_L4 != GSO_INDEX(NETIF_F_GSO_UDP_L4_BIT)); >> + BUILD_BUG_ON(SKB_GSO_FRAGLIST != GSO_INDEX(NETIF_F_GSO_FRAGLIST_BIT)); >> >> return (features & feature) == feature; >> } >> -- >> 2.33.0 > Thanks, > Olek > . >