Commit 4f325e26 authored by Julian Anastasov's avatar Julian Anastasov Committed by Pablo Neira Ayuso
Browse files

ipvs: dynamically limit the connection hash table 



As we allow the hash table to be configured to rows above 2^20,
we should limit it depending on the available memory to some
sane values. Switch to kvmalloc allocation to better select
the needed allocation type.

Signed-off-by: default avatarJulian Anastasov <ja@ssi.bg>
Signed-off-by: default avatarPablo Neira Ayuso <pablo@netfilter.org>
parent 04292c69

net/netfilter/ipvs/ip_vs_conn.c

+17 −9
Original line number Diff line number Diff line
@@ -26,7 +26,6 @@ 
#include <linux/net.h>

#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/vmalloc.h>

#include <linux/proc_fs.h>		/* for proc_net_* */

#include <linux/slab.h>

#include <linux/seq_file.h>
@@ -1482,13 +1481,21 @@ void __net_exit ip_vs_conn_net_cleanup(struct netns_ipvs *ipvs) 
int __init ip_vs_conn_init(void)

{

	size_t tab_array_size;

	int max_avail;

#if BITS_PER_LONG > 32

	int max = 27;

#else

	int max = 20;

#endif

	int min = 8;

	int idx;



	/* Compute size and mask */

	if (ip_vs_conn_tab_bits < 8 || ip_vs_conn_tab_bits > 27) {

		pr_info("conn_tab_bits not in [8, 27]. Using default value\n");

		ip_vs_conn_tab_bits = CONFIG_IP_VS_TAB_BITS;

	}

	max_avail = order_base_2(totalram_pages()) + PAGE_SHIFT;

	max_avail -= 2;		/* ~4 in hash row */

	max_avail -= 1;		/* IPVS up to 1/2 of mem */

	max_avail -= order_base_2(sizeof(struct ip_vs_conn));

	max = clamp(max, min, max_avail);

	ip_vs_conn_tab_bits = clamp_val(ip_vs_conn_tab_bits, min, max);

	ip_vs_conn_tab_size = 1 << ip_vs_conn_tab_bits;

	ip_vs_conn_tab_mask = ip_vs_conn_tab_size - 1;
@@ -1497,7 +1504,8 @@ int __init ip_vs_conn_init(void) 
	 */

	tab_array_size = array_size(ip_vs_conn_tab_size,

				    sizeof(*ip_vs_conn_tab));

	ip_vs_conn_tab = vmalloc(tab_array_size);

	ip_vs_conn_tab = kvmalloc_array(ip_vs_conn_tab_size,

					sizeof(*ip_vs_conn_tab), GFP_KERNEL);

	if (!ip_vs_conn_tab)

		return -ENOMEM;
@@ -1506,7 +1514,7 @@ int __init ip_vs_conn_init(void) 
					      sizeof(struct ip_vs_conn), 0,

					      SLAB_HWCACHE_ALIGN, NULL);

	if (!ip_vs_conn_cachep) {

		vfree(ip_vs_conn_tab);

		kvfree(ip_vs_conn_tab);

		return -ENOMEM;

	}
@@ -1534,5 +1542,5 @@ void ip_vs_conn_cleanup(void) 
	rcu_barrier();

	/* Release the empty cache */

	kmem_cache_destroy(ip_vs_conn_cachep);

	vfree(ip_vs_conn_tab);

	kvfree(ip_vs_conn_tab);

}