diff options
| author | Florian Westphal <fw@strlen.de> | 2015-06-11 01:34:55 +0200 |
|---|---|---|
| committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2015-06-12 14:27:10 +0200 |
| commit | 482cfc318559e2527dfd8513582d2fdb276e47c2 (patch) | |
| tree | 66160977937cbc47d024b93806b85475dab1c026 /include/linux | |
| parent | 71ae0dff02d756e4d2ca710b79f2ff5390029a5f (diff) | |
netfilter: xtables: avoid percpu ruleset duplication
We store the rule blob per (possible) cpu. Unfortunately this means we can
waste lot of memory on big smp machines. ipt_entry structure ('rule head')
is 112 byte, so e.g. with maxcpu=64 one single rule eats
close to 8k RAM.
Since previous patch made counters percpu it appears there is nothing
left in the rule blob that needs to be percpu.
On my test system (144 possible cpus, 400k dummy rules) this
change saves close to 9 Gigabyte of RAM.
Reported-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/netfilter/x_tables.h | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/include/linux/netfilter/x_tables.h b/include/linux/netfilter/x_tables.h index b77ab9f17641..9969d79dcde1 100644 --- a/include/linux/netfilter/x_tables.h +++ b/include/linux/netfilter/x_tables.h @@ -224,9 +224,9 @@ struct xt_table_info { unsigned int stacksize; unsigned int __percpu *stackptr; void ***jumpstack; - /* ipt_entry tables: one per CPU */ + /* Note : this field MUST be the last one, see XT_TABLE_INFO_SZ */ - void *entries[1]; + void *entries; }; #define XT_TABLE_INFO_SZ (offsetof(struct xt_table_info, entries) \ |