netdev - [PATCH, take2] netfilter : struct xt_table

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Date:	Wed, 14 Nov 2007 22:50:00 +0100
From:	Eric Dumazet <dada1@...mosbay.com>
To:	Patrick McHardy <kaber@...sh.net>,
	"David S. Miller" <davem@...emloft.net>
CC:	Linux Netdev List <netdev@...r.kernel.org>,
	Netfilter Development Mailinglist 
	<netfilter-devel@...ts.netfilter.org>
Subject: [PATCH, take2] netfilter : struct xt_table_info diet

Hi David & Patrick

Please find an updated version of this patch, against net-2.6.25

(relax the check against sizes of loaded tables, using a divide by 
num_possible_cpus() in place of NR_CPUS)

Thank you


[PATCH] netfilter : struct xt_table_info diet

Instead of using a big array of NR_CPUS entries, we can compute the size
needed at runtime, using nr_cpu_ids

This should save some ram (especially on David's machines where NR_CPUS=4096 :
32 KB can be saved per table, and 64KB for dynamically allocated ones (because
of slab/slub alignements) )

In particular, the 'bootstrap' tables are not any more static (in data
section) but on stack as their size is now very small.

This also should reduce the size used on stack in compat functions
(get_info() declares an automatic variable, that could be bigger than kernel
stack size for big NR_CPUS)

Signed-off-by: Eric Dumazet <dada1@...mosbay.com>

View attachment "xt_table_info_diet.patch" of type "text/plain" (5733 bytes)