Commit 3dc43e3e authored by Glauber Costa's avatar Glauber Costa Committed by David S. Miller
Browse files

per-netns ipv4 sysctl_tcp_mem 



This patch allows each namespace to independently set up
its levels for tcp memory pressure thresholds. This patch
alone does not buy much: we need to make this values
per group of process somehow. This is achieved in the
patches that follows in this patchset.

Signed-off-by: default avatarGlauber Costa <glommer@parallels.com>
Reviewed-by: default avatarKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
CC: David S. Miller <davem@davemloft.net>
CC: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent d1a4c0b3

include/net/netns/ipv4.h

+1 −0
Original line number Diff line number Diff line
@@ -55,6 +55,7 @@ struct netns_ipv4 { 
	int current_rt_cache_rebuild_count;



	unsigned int sysctl_ping_group_range[2];

	long sysctl_tcp_mem[3];



	atomic_t rt_genid;

	atomic_t dev_addr_genid;

include/net/tcp.h

+0 −1
Original line number Diff line number Diff line
@@ -230,7 +230,6 @@ extern int sysctl_tcp_fack; 
extern int sysctl_tcp_reordering;

extern int sysctl_tcp_ecn;

extern int sysctl_tcp_dsack;

extern long sysctl_tcp_mem[3];

extern int sysctl_tcp_wmem[3];

extern int sysctl_tcp_rmem[3];

extern int sysctl_tcp_app_win;

net/ipv4/af_inet.c

+2 −0
Original line number Diff line number Diff line
@@ -1672,6 +1672,8 @@ static int __init inet_init(void) 
	ip_static_sysctl_init();

#endif



	tcp_prot.sysctl_mem = init_net.ipv4.sysctl_tcp_mem;



	/*

	 *	Add all the base protocols.

	 */

net/ipv4/sysctl_net_ipv4.c

+44 −7
Original line number Diff line number Diff line
@@ -14,6 +14,7 @@ 
#include <linux/init.h>

#include <linux/slab.h>

#include <linux/nsproxy.h>

#include <linux/swap.h>

#include <net/snmp.h>

#include <net/icmp.h>

#include <net/ip.h>
@@ -174,6 +175,36 @@ static int proc_allowed_congestion_control(ctl_table *ctl, 
	return ret;

}



static int ipv4_tcp_mem(ctl_table *ctl, int write,

			   void __user *buffer, size_t *lenp,

			   loff_t *ppos)

{

	int ret;

	unsigned long vec[3];

	struct net *net = current->nsproxy->net_ns;



	ctl_table tmp = {

		.data = &vec,

		.maxlen = sizeof(vec),

		.mode = ctl->mode,

	};



	if (!write) {

		ctl->data = &net->ipv4.sysctl_tcp_mem;

		return proc_doulongvec_minmax(ctl, write, buffer, lenp, ppos);

	}



	ret = proc_doulongvec_minmax(&tmp, write, buffer, lenp, ppos);

	if (ret)

		return ret;



	net->ipv4.sysctl_tcp_mem[0] = vec[0];

	net->ipv4.sysctl_tcp_mem[1] = vec[1];

	net->ipv4.sysctl_tcp_mem[2] = vec[2];



	return 0;

}



static struct ctl_table ipv4_table[] = {

	{

		.procname	= "tcp_timestamps",
@@ -432,13 +463,6 @@ static struct ctl_table ipv4_table[] = { 
		.mode		= 0644,

		.proc_handler	= proc_dointvec

	},

	{

		.procname	= "tcp_mem",

		.data		= &sysctl_tcp_mem,

		.maxlen		= sizeof(sysctl_tcp_mem),

		.mode		= 0644,

		.proc_handler	= proc_doulongvec_minmax

	},

	{

		.procname	= "tcp_wmem",

		.data		= &sysctl_tcp_wmem,
@@ -721,6 +745,12 @@ static struct ctl_table ipv4_net_table[] = { 
		.mode		= 0644,

		.proc_handler	= ipv4_ping_group_range,

	},

	{

		.procname	= "tcp_mem",

		.maxlen		= sizeof(init_net.ipv4.sysctl_tcp_mem),

		.mode		= 0644,

		.proc_handler	= ipv4_tcp_mem,

	},

	{ }

};
@@ -734,6 +764,7 @@ EXPORT_SYMBOL_GPL(net_ipv4_ctl_path); 
static __net_init int ipv4_sysctl_init_net(struct net *net)

{

	struct ctl_table *table;

	unsigned long limit;



	table = ipv4_net_table;

	if (!net_eq(net, &init_net)) {
@@ -769,6 +800,12 @@ static __net_init int ipv4_sysctl_init_net(struct net *net) 


	net->ipv4.sysctl_rt_cache_rebuild_count = 4;



	limit = nr_free_buffer_pages() / 8;

	limit = max(limit, 128UL);

	net->ipv4.sysctl_tcp_mem[0] = limit / 4 * 3;

	net->ipv4.sysctl_tcp_mem[1] = limit;

	net->ipv4.sysctl_tcp_mem[2] = net->ipv4.sysctl_tcp_mem[0] * 2;



	net->ipv4.ipv4_hdr = register_net_sysctl_table(net,

			net_ipv4_ctl_path, table);

	if (net->ipv4.ipv4_hdr == NULL)

net/ipv4/tcp.c

+2 −9
Original line number Diff line number Diff line
@@ -282,11 +282,9 @@ int sysctl_tcp_fin_timeout __read_mostly = TCP_FIN_TIMEOUT; 
struct percpu_counter tcp_orphan_count;

EXPORT_SYMBOL_GPL(tcp_orphan_count);



long sysctl_tcp_mem[3] __read_mostly;

int sysctl_tcp_wmem[3] __read_mostly;

int sysctl_tcp_rmem[3] __read_mostly;



EXPORT_SYMBOL(sysctl_tcp_mem);

EXPORT_SYMBOL(sysctl_tcp_rmem);

EXPORT_SYMBOL(sysctl_tcp_wmem);
@@ -3278,14 +3276,9 @@ void __init tcp_init(void) 
	sysctl_tcp_max_orphans = cnt / 2;

	sysctl_max_syn_backlog = max(128, cnt / 256);



	limit = nr_free_buffer_pages() / 8;

	limit = max(limit, 128UL);

	sysctl_tcp_mem[0] = limit / 4 * 3;

	sysctl_tcp_mem[1] = limit;

	sysctl_tcp_mem[2] = sysctl_tcp_mem[0] * 2;



	/* Set per-socket limits to no more than 1/128 the pressure threshold */

	limit = ((unsigned long)sysctl_tcp_mem[1]) << (PAGE_SHIFT - 7);

	limit = ((unsigned long)init_net.ipv4.sysctl_tcp_mem[1])

		<< (PAGE_SHIFT - 7);

	max_share = min(4UL*1024*1024, limit);



	sysctl_tcp_wmem[0] = SK_MEM_QUANTUM;

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