[PATCH 2/6] netfilter: ipv6: nf_defrag: reduce struct net memory waste
From: Pablo Neira Ayuso <pablo@netfilter.org>
Date: 2018-06-27 15:22:33
Also in:
netfilter-devel
Subsystem:
networking [general], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
From: Eric Dumazet <edumazet@google.com>
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 <edumazet@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
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 47e35cce3b64..a71264d75d7f 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 c978a31b0f84..762ac9931b62 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 5e0332014c17..a452d99c9f52 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); }
--
2.11.0