From nobody Wed Feb 11 13:28:47 2026 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 7408DC7EE2A for ; Mon, 8 May 2023 16:53:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234108AbjEHQxb (ORCPT ); Mon, 8 May 2023 12:53:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50964 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230414AbjEHQx3 (ORCPT ); Mon, 8 May 2023 12:53:29 -0400 Received: from smtp.smtpout.orange.fr (smtp-26.smtpout.orange.fr [80.12.242.26]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4CCB049DE for ; Mon, 8 May 2023 09:53:25 -0700 (PDT) Received: from pop-os.home ([86.243.2.178]) by smtp.orange.fr with ESMTPA id w46xpAkeMfMwtw46xpf0cB; Mon, 08 May 2023 18:53:23 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=wanadoo.fr; s=t20230301; t=1683564803; bh=lm5x+NwYR0+zI73AdgqIwZ7OxGK1VHk4xnXiyrCtxyI=; h=From:To:Cc:Subject:Date; b=TffSdUf8plGRs/fzLhYW2m+zoyex7bE0y+J2jIt9i6EFeFdGap/wrfNTUt4hfOAD4 6hg7Rja0JgT98UjFX9lI6MgVAXfJiboQ01sQiV+qLQimAy6cwkQKY4Adg1/3BvV1Eq Pe2qRSRCcKRv9jmq52vGIYVZpSvXRPAVQNa7qo7RBmglCKs8YvpWqTe7RaUhZ1sDfD wGtE1gdhkYosYQlcn9jhjeQZUFOCPtfeyVpTuH7P/eqkdcw16IU/pllrekehtUXHme iXKoxhMMWioWmwV/MGsDSmDLJ6df2NpYxfqA+pMTxJE1OyRoc3lrMQ2+6zh42oqw8s 9ZxmWry12MF5g== X-ME-Helo: pop-os.home X-ME-Auth: Y2hyaXN0b3BoZS5qYWlsbGV0QHdhbmFkb28uZnI= X-ME-Date: Mon, 08 May 2023 18:53:23 +0200 X-ME-IP: 86.243.2.178 From: Christophe JAILLET To: Pablo Neira Ayuso , Jozsef Kadlecsik , Florian Westphal , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni Cc: linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org, Christophe JAILLET , netfilter-devel@vger.kernel.org, coreteam@netfilter.org, netdev@vger.kernel.org Subject: [PATCH net-next] netfilter: Reorder fields in 'struct nf_conntrack_expect' Date: Mon, 8 May 2023 18:53:14 +0200 Message-Id: <5cdb1f50f2e9dc80dbf86cf8667056eacfd36a09.1683564754.git.christophe.jaillet@wanadoo.fr> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Group some variables based on their sizes to reduce holes. On x86_64, this shrinks the size of 'struct nf_conntrack_expect' from 264 to 256 bytes. This structure deserve a dedicated cache, so reducing its size looks nice. Signed-off-by: Christophe JAILLET Reviewed-by: Simon Horman --- Using pahole Before: =3D=3D=3D=3D=3D=3D struct nf_conntrack_expect { struct hlist_node lnode; /* 0 16 */ struct hlist_node hnode; /* 16 16 */ struct nf_conntrack_tuple tuple; /* 32 40 */ /* --- cacheline 1 boundary (64 bytes) was 8 bytes ago --- */ struct nf_conntrack_tuple_mask mask; /* 72 20 */ /* XXX 4 bytes hole, try to pack */ void (*expectfn)(struct nf_conn *, struct nf_conntra= ck_expect *); /* 96 8 */ struct nf_conntrack_helper * helper; /* 104 8 */ struct nf_conn * master; /* 112 8 */ struct timer_list timeout; /* 120 88 */ /* --- cacheline 3 boundary (192 bytes) was 16 bytes ago --- */ refcount_t use; /* 208 4 */ unsigned int flags; /* 212 4 */ unsigned int class; /* 216 4 */ union nf_inet_addr saved_addr; /* 220 16 */ union nf_conntrack_man_proto saved_proto; /* 236 2 */ /* XXX 2 bytes hole, try to pack */ enum ip_conntrack_dir dir; /* 240 4 */ /* XXX 4 bytes hole, try to pack */ struct callback_head rcu __attribute__((__aligned__(8))); /* 248 = 16 */ /* size: 264, cachelines: 5, members: 15 */ /* sum members: 254, holes: 3, sum holes: 10 */ /* forced alignments: 1, forced holes: 1, sum forced holes: 4 */ /* last cacheline: 8 bytes */ } __attribute__((__aligned__(8))); After: =3D=3D=3D=3D=3D struct nf_conntrack_expect { struct hlist_node lnode; /* 0 16 */ struct hlist_node hnode; /* 16 16 */ struct nf_conntrack_tuple tuple; /* 32 40 */ /* --- cacheline 1 boundary (64 bytes) was 8 bytes ago --- */ struct nf_conntrack_tuple_mask mask; /* 72 20 */ refcount_t use; /* 92 4 */ unsigned int flags; /* 96 4 */ unsigned int class; /* 100 4 */ void (*expectfn)(struct nf_conn *, struct nf_conntra= ck_expect *); /* 104 8 */ struct nf_conntrack_helper * helper; /* 112 8 */ struct nf_conn * master; /* 120 8 */ /* --- cacheline 2 boundary (128 bytes) --- */ struct timer_list timeout; /* 128 88 */ /* --- cacheline 3 boundary (192 bytes) was 24 bytes ago --- */ union nf_inet_addr saved_addr; /* 216 16 */ union nf_conntrack_man_proto saved_proto; /* 232 2 */ /* XXX 2 bytes hole, try to pack */ enum ip_conntrack_dir dir; /* 236 4 */ struct callback_head rcu __attribute__((__aligned__(8))); /* 240 = 16 */ /* size: 256, cachelines: 4, members: 15 */ /* sum members: 254, holes: 1, sum holes: 2 */ /* forced alignments: 1 */ } __attribute__((__aligned__(8))); --- include/net/netfilter/nf_conntrack_expect.h | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) diff --git a/include/net/netfilter/nf_conntrack_expect.h b/include/net/netf= ilter/nf_conntrack_expect.h index 0855b60fba17..cf0d81be5a96 100644 --- a/include/net/netfilter/nf_conntrack_expect.h +++ b/include/net/netfilter/nf_conntrack_expect.h @@ -26,6 +26,15 @@ struct nf_conntrack_expect { struct nf_conntrack_tuple tuple; struct nf_conntrack_tuple_mask mask; =20 + /* Usage count. */ + refcount_t use; + + /* Flags */ + unsigned int flags; + + /* Expectation class */ + unsigned int class; + /* Function to call after setup and insertion */ void (*expectfn)(struct nf_conn *new, struct nf_conntrack_expect *this); @@ -39,15 +48,6 @@ struct nf_conntrack_expect { /* Timer function; deletes the expectation. */ struct timer_list timeout; =20 - /* Usage count. */ - refcount_t use; - - /* Flags */ - unsigned int flags; - - /* Expectation class */ - unsigned int class; - #if IS_ENABLED(CONFIG_NF_NAT) union nf_inet_addr saved_addr; /* This is the original per-proto part, used to map the --=20 2.34.1