From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from szxga06-in.huawei.com (szxga06-in.huawei.com [45.249.212.32]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9AD2B27B344; Thu, 28 Aug 2025 06:44:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.32 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756363457; cv=none; b=H/sjbbZ2WzVt0J2rUJxRVn0qN3grPdH97+2zNJHUaUdP9wWHvXPquX2kd64fQMO7xpRPlTMahY/vPYIrn4mDaNpnZ0EPms53/qvl5JYmAUJWha9UHgrbut5v0wqxTS/9kD57e4nnSIuR3s7jCepSTs92plb4gXZWCT5+ti7QXAk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756363457; c=relaxed/simple; bh=8zZBLR8WpA2QUeNR1rr53cjyWEPuk80dOXfqigSquRg=; h=Message-ID:Date:MIME-Version:Subject:From:To:CC:References: In-Reply-To:Content-Type; b=ONgmDb0nA9A/FDXAw9s5YQTtdHsUZZOzRRwP7rZLw0ZVaf2SksuQHegs9j8t6r0xgwkw1Snx/ZvTAtMjeAHAoBbm22xubKds7MEssAyckXSosPuoa4ONS96Y6Y5HjJ3DJuHowqsAqPvphLRnTTb7MTTrfRQZ+WVq9SpK8HDNOms= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=huawei.com; arc=none smtp.client-ip=45.249.212.32 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Received: from mail.maildlp.com (unknown [172.19.88.163]) by szxga06-in.huawei.com (SkyGuard) with ESMTP id 4cCBjR2sG2z27jM8; Thu, 28 Aug 2025 14:45:15 +0800 (CST) Received: from dggpemf500002.china.huawei.com (unknown [7.185.36.57]) by mail.maildlp.com (Postfix) with ESMTPS id 9DD0618005F; Thu, 28 Aug 2025 14:44:08 +0800 (CST) Received: from [10.174.179.113] (10.174.179.113) by dggpemf500002.china.huawei.com (7.185.36.57) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Thu, 28 Aug 2025 14:44:07 +0800 Message-ID: <83aeba1c-27ff-4a92-b91e-5719be879e7a@huawei.com> Date: Thu, 28 Aug 2025 14:44:07 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH net-next] ipv6: sit: Add ipip6_tunnel_dst_find() for cleanup From: Yue Haibing To: Alexander Lobakin CC: , , , , , , , References: <20250827040027.1013335-1-yuehaibing@huawei.com> <5b0d6d7c-b65e-4022-b028-05f45fe56bf9@huawei.com> Content-Language: en-US In-Reply-To: <5b0d6d7c-b65e-4022-b028-05f45fe56bf9@huawei.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8bit X-ClientProxiedBy: kwepems100001.china.huawei.com (7.221.188.238) To dggpemf500002.china.huawei.com (7.185.36.57) On 2025/8/28 14:13, Yue Haibing wrote: > On 2025/8/27 22:45, Alexander Lobakin wrote: >> From: Yue Haibing >> Date: Wed, 27 Aug 2025 12:00:27 +0800 >> >>> Extract the dst lookup logic from ipip6_tunnel_xmit() into new helper >>> ipip6_tunnel_dst_find() to reduce code duplication and enhance readability. >>> >>> No functional change intended. >> >> ...but bloat-o-meter stats would be nice to see here. I'm curious >> whether the object code got any changes or the compilers still just >> inline this function to both call sites. On a x86_64, with allmodconfig: ./scripts/bloat-o-meter -c net/ipv6/sit.o net/ipv6/sit-after.o add/remove: 2/0 grow/shrink: 1/1 up/down: 1770/-2152 (-382) Function old new delta ipip6_tunnel_dst_find - 1697 +1697 __pfx_ipip6_tunnel_dst_find - 64 +64 ipip6_tunnel_xmit.isra.cold 79 88 +9 ipip6_tunnel_xmit.isra 9910 7758 -2152 Total: Before=70060, After=69678, chg -0.55% add/remove: 2/2 grow/shrink: 0/1 up/down: 16/-72 (-56) Data old new delta __UNIQUE_ID___addressable_init_module2092 - 8 +8 __UNIQUE_ID___addressable_cleanup_module2093 - 8 +8 __UNIQUE_ID___addressable_init_module2093 8 - -8 __UNIQUE_ID___addressable_cleanup_module2094 8 - -8 descriptor 112 56 -56 Total: Before=752, After=696, chg -7.45% add/remove: 1/1 grow/shrink: 2/2 up/down: 55/-51 (4) RO Data old new delta __UNIQUE_ID_modinfo2094 - 43 +43 __UNIQUE_ID_modinfo2096 12 20 +8 __func__ 55 59 +4 __UNIQUE_ID_modinfo2097 20 18 -2 __UNIQUE_ID_modinfo2098 18 - -18 __UNIQUE_ID_modinfo2095 43 12 -31 Total: Before=1725, After=1729, chg +0.23% > > On a x86_64, with allmodconfig: > before: > text data bss dec hex filename > 96973 14687 256 111916 1b52c net/ipv6/sit.o > > after: > text data bss dec hex filename > 96699 14599 256 111554 1b3c2 net/ipv6/sit.o > > I will add this in v2. > >> >>> >>> Signed-off-by: Yue Haibing >>> --- >>> net/ipv6/sit.c | 93 +++++++++++++++++++++++--------------------------- >>> 1 file changed, 43 insertions(+), 50 deletions(-) >>> >>> diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c >>> index 12496ba1b7d4..bcd261ff985b 100644 >>> --- a/net/ipv6/sit.c >>> +++ b/net/ipv6/sit.c >>> @@ -848,6 +848,47 @@ static inline __be32 try_6rd(struct ip_tunnel *tunnel, >>> return dst; >>> } >>> >>> +static bool ipip6_tunnel_dst_find(struct sk_buff *skb, __be32 *dst, >>> + bool is_isatap) >>> +{ >>> + const struct ipv6hdr *iph6 = ipv6_hdr(skb); >>> + struct neighbour *neigh = NULL; >>> + const struct in6_addr *addr6; >>> + bool found = false; >>> + int addr_type; >>> + >>> + if (skb_dst(skb)) >>> + neigh = dst_neigh_lookup(skb_dst(skb), &iph6->daddr); >>> + >>> + if (!neigh) { >>> + net_dbg_ratelimited("nexthop == NULL\n"); >>> + return found; >> >> Return false here right away. >> >>> + } >>> + >>> + addr6 = (const struct in6_addr *)&neigh->primary_key; >>> + addr_type = ipv6_addr_type(addr6); >>> + >>> + if (is_isatap) { >>> + if ((addr_type & IPV6_ADDR_UNICAST) && >>> + ipv6_addr_is_isatap(addr6)) { >>> + *dst = addr6->s6_addr32[3]; >>> + found = true; >>> + } >>> + } else { >>> + if (addr_type == IPV6_ADDR_ANY) { >>> + addr6 = &ipv6_hdr(skb)->daddr; >>> + addr_type = ipv6_addr_type(addr6); >>> + } >>> + >>> + if ((addr_type & IPV6_ADDR_COMPATv4) != 0) { >>> + *dst = addr6->s6_addr32[3]; >>> + found = true; >>> + } >>> + } >>> + neigh_release(neigh); >>> + return found; >> >> I'd put 2 additional newlines here: >> >> } >> >> neigh_release(neigh); >> >> return found; >> } >> >> for readability purposes and also a NL before the final `return` is >> usually mandatory. > > OK， thanks. >> >> Thanks, >> Olek >> > >