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 C88A4C32793 for ; Fri, 19 Aug 2022 22:54:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243255AbiHSWy1 (ORCPT ); Fri, 19 Aug 2022 18:54:27 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43412 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242812AbiHSWy0 (ORCPT ); Fri, 19 Aug 2022 18:54:26 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 93ADB2BB03; Fri, 19 Aug 2022 15:54:25 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 4FFCCB8280F; Fri, 19 Aug 2022 22:54:24 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C1553C43140; Fri, 19 Aug 2022 22:54:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1660949663; bh=X0ogePNNlSeDRsY3fzWimjrtxpMAJRwCWte81D4J8fU=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=esGVZEqm4i1XkWJJfodRqvZeUsrLFqo6ppzuJjfKj/pg37vVV5ezs+cau9Qi5+ySs nL2Ff5ChwGzN5l4uYBiIEhff3ph1mpCd/EJqj6hHgMgC0wOGoKtC7hZ2OKHyvrruSW 0JhsWRaueEsiu6ZKoTmBb2RuA1gL1L8AbLrk2IwmZDsJGmWE2fLDpr/3O9DvXDhWO0 O995cPmwQIL+ykEBy8jmvT2iRt25WK8JEZEa+UTB0teLl0hxIsRjQRLK53paQ2W0zX YL0SnEJZc3Mji4FDz7ofro97SaSd5ShfypFp8JdgTvYqaCFSMJzTvIV1qqmN6EtTon GxkwT/fTNbJXg== Date: Fri, 19 Aug 2022 15:54:21 -0700 From: Jakub Kicinski To: Toke =?UTF-8?B?SMO4aWxhbmQtSsO4cmdlbnNlbg==?= Cc: "David S. Miller" , Eric Dumazet , Paolo Abeni , netdev@vger.kernel.org, bpf@vger.kernel.org Subject: Re: [PATCH bpf-next 1/3] dev: Move received_rps counter next to RPS members in softnet data Message-ID: <20220819155421.3ca7d6d6@kernel.org> In-Reply-To: <87bksgv26h.fsf@toke.dk> References: <20220818165906.64450-1-toke@redhat.com> <20220818165906.64450-2-toke@redhat.com> <20220818200143.7d534a41@kernel.org> <87bksgv26h.fsf@toke.dk> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Fri, 19 Aug 2022 14:38:14 +0200 Toke H=C3=B8iland-J=C3=B8rgensen wrote: > Jakub Kicinski writes: > > On Thu, 18 Aug 2022 18:59:03 +0200 Toke H=C3=B8iland-J=C3=B8rgensen wro= te: =20 > >> Move the received_rps counter value next to the other RPS-related memb= ers > >> in softnet_data. This closes two four-byte holes in the structure, mak= ing > >> room for another pointer in the first two cache lines without bumping = the > >> xmit struct to its own line. =20 > > > > What's the pointer you're making space for (which I hope will explain > > why this patch is part of this otherwise bpf series)? =20 >=20 > The XDP queueing series adds a pointer to keep track of which interfaces > were scheduled for transmission using the XDP dequeue hook (similar to > how the qdisc wake code works): >=20 > https://lore.kernel.org/r/20220713111430.134810-12-toke@redhat.com I see, it makes more sense now :) > Note that it's still up in the air if this ends up being the way this > will be implemented, so I'm OK with dropping this patch for now if you'd > rather wait until it's really needed. OTOH it also seemed like a benign > change on its own, so I figured I might as well include this patch when > sending these out. WDYT? Whatever is easiest :)