From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: [PATCH net] netfilter: ipv6: nf_defrag: reduce struct net memory waste Date: Wed, 13 Jun 2018 10:11:56 -0700 Message-ID: <20180613171156.240889-1-edumazet@google.com> Cc: netfilter-devel@vger.kernel.org, netdev , Eric Dumazet , Eric Dumazet To: Pablo Neira Ayuso , Jozsef Kadlecsik , Florian Westphal Return-path: Received: from mail-pf0-f193.google.com ([209.85.192.193]:37856 "EHLO mail-pf0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934794AbeFMRMA (ORCPT ); Wed, 13 Jun 2018 13:12:00 -0400 Received: by mail-pf0-f193.google.com with SMTP id y5-v6so1755256pfn.4 for ; Wed, 13 Jun 2018 10:12:00 -0700 (PDT) Sender: netdev-owner@vger.kernel.org List-ID: It is a waste of memory to use a full "struct netns_sysctl_ipv6" while only one pointer is really used, considering netns_sysctl_ipv6 keeps growing. Also, since "struct netns_frags" has cache line alignment, it is better to move the frags_hdr pointer outside, otherwise we spend a full cache line for this pointer. This saves 192 bytes of memory per netns. Fixes: c038a767cd69 ("ipv6: add a new namespace for nf_conntrack_reasm") Signed-off-by: Eric Dumazet --- include/net/net_namespace.h | 1 + include/net/netns/ipv6.h | 1 - net/ipv6/netfilter/nf_conntrack_reasm.c | 6 +++--- 3 files changed, 4 insertions(+), 4 deletions(-) diff --git a/include/net/net_namespace.h b/include/net/net_namespace.h index 47e35cce3b648d696b127ed7bd643036128795f6..a71264d75d7f98d28f92dfd861ffe6e0d39c0198 100644 --- a/include/net/net_namespace.h +++ b/include/net/net_namespace.h @@ -128,6 +128,7 @@ struct net { #endif #if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6) struct netns_nf_frag nf_frag; + struct ctl_table_header *nf_frag_frags_hdr; #endif struct sock *nfnl; struct sock *nfnl_stash; diff --git a/include/net/netns/ipv6.h b/include/net/netns/ipv6.h index c978a31b0f846210b4c2a369af960d5349b5395a..762ac9931b6251152b6ee0e5780df0f7b073f3e6 100644 --- a/include/net/netns/ipv6.h +++ b/include/net/netns/ipv6.h @@ -109,7 +109,6 @@ struct netns_ipv6 { #if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6) struct netns_nf_frag { - struct netns_sysctl_ipv6 sysctl; struct netns_frags frags; }; #endif diff --git a/net/ipv6/netfilter/nf_conntrack_reasm.c b/net/ipv6/netfilter/nf_conntrack_reasm.c index 5e0332014c1738999e680c1853829f384e880284..a452d99c9f5281b5e5d7e6f0162611deeb82212d 100644 --- a/net/ipv6/netfilter/nf_conntrack_reasm.c +++ b/net/ipv6/netfilter/nf_conntrack_reasm.c @@ -107,7 +107,7 @@ static int nf_ct_frag6_sysctl_register(struct net *net) if (hdr == NULL) goto err_reg; - net->nf_frag.sysctl.frags_hdr = hdr; + net->nf_frag_frags_hdr = hdr; return 0; err_reg: @@ -121,8 +121,8 @@ static void __net_exit nf_ct_frags6_sysctl_unregister(struct net *net) { struct ctl_table *table; - table = net->nf_frag.sysctl.frags_hdr->ctl_table_arg; - unregister_net_sysctl_table(net->nf_frag.sysctl.frags_hdr); + table = net->nf_frag_frags_hdr->ctl_table_arg; + unregister_net_sysctl_table(net->nf_frag_frags_hdr); if (!net_eq(net, &init_net)) kfree(table); } -- 2.18.0.rc1.242.g61856ae69a-goog