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=-16.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 3010FC433C1 for ; Wed, 24 Mar 2021 10:35:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F029861A07 for ; Wed, 24 Mar 2021 10:35:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235832AbhCXKfR (ORCPT ); Wed, 24 Mar 2021 06:35:17 -0400 Received: from mail.kernel.org ([198.145.29.99]:58344 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233398AbhCXKe5 (ORCPT ); Wed, 24 Mar 2021 06:34:57 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 17E3361A01; Wed, 24 Mar 2021 10:34:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1616582096; bh=9Z2UIME5BPL9q3dzEzV84xwr0G+Ct4YPKT5HcX86PpE=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=OYjKAX2+aM0uhO5qQz0EdEf+Te7ComRwLmBsS2aTdvvnBX3xLOFY2Lp2DI9arPHPW SpMgjEEAVfkQZ1yQzZaHZOm4J26olsj8Olr7nkAJ3v2/W5/vcwft/3HV+SDKgC9xBC aDPoUz1j8pkGvCOPL+4l9X1Ta4y6tjuX2d8+39xNMO5YTuV3tpMPNpbaTfdxvcURrY YiTTFjtneDk2z8OnoXnDtjtdtnUcTuNed5x24yIJpEKRRPmrhaIBzgN9C7+uDUANWY SbfQJ3o8h0e6/xEkuDfhglpQsRPQ4QI+HYT7db4WSa3SZ9Bsk5pFtLns9iLL8omTef rwH3SF+2UWgVg== Date: Wed, 24 Mar 2021 12:34:52 +0200 From: Leon Romanovsky To: Yejune Deng Cc: davem@davemloft.net, yoshfuji@linux-ipv6.org, dsahern@kernel.org, kuba@kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, yejune@gmail.com Subject: Re: [PATCH 1/2] net: ipv4: route.c: add likely() statements Message-ID: References: <20210324030923.17203-1-yejune.deng@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210324030923.17203-1-yejune.deng@gmail.com> Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Wed, Mar 24, 2021 at 11:09:22AM +0800, Yejune Deng wrote: > Add likely() statements in ipv4_confirm_neigh() for 'rt->rt_gw_family > == AF_INET'. Why? Such macros are beneficial in only specific cases, most of the time, likely/unlikely is cargo cult. > > Signed-off-by: Yejune Deng > --- > net/ipv4/route.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/net/ipv4/route.c b/net/ipv4/route.c > index fa68c2612252..5762d9bc671c 100644 > --- a/net/ipv4/route.c > +++ b/net/ipv4/route.c > @@ -440,7 +440,7 @@ static void ipv4_confirm_neigh(const struct dst_entry *dst, const void *daddr) > struct net_device *dev = dst->dev; > const __be32 *pkey = daddr; > > - if (rt->rt_gw_family == AF_INET) { > + if (likely(rt->rt_gw_family == AF_INET)) { > pkey = (const __be32 *)&rt->rt_gw4; > } else if (rt->rt_gw_family == AF_INET6) { > return __ipv6_confirm_neigh_stub(dev, &rt->rt_gw6); > -- > 2.29.0 >