From d1a4c0b37c296e600ffe08edb0db2dc1b8f550d7 Mon Sep 17 00:00:00 2001
From: Glauber Costa <glommer@parallels.com>
Date: Sun, 11 Dec 2011 21:47:04 +0000
Subject: tcp memory pressure controls
This patch introduces memory pressure controls for the tcp
protocol. It uses the generic socket memory pressure code
introduced in earlier patches, and fills in the
necessary data in cg_proto struct.
Signed-off-by: Glauber Costa <glommer@parallels.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujtisu.com>
CC: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
include/net/tcp_memcontrol.h | 17 +++++++++++++++++
1 file changed, 17 insertions(+)
create mode 100644 include/net/tcp_memcontrol.h
(limited to 'include/net/tcp_memcontrol.h')
diff --git a/include/net/tcp_memcontrol.h b/include/net/tcp_memcontrol.h
new file mode 100644
index 00000000000..5f5e1582d76
--- /dev/null
+++ b/include/net/tcp_memcontrol.h
@@ -0,0 +1,17 @@
+#ifndef _TCP_MEMCG_H
+#define _TCP_MEMCG_H
+
+struct tcp_memcontrol {
+ struct cg_proto cg_proto;
+ /* per-cgroup tcp memory pressure knobs */
+ struct res_counter tcp_memory_allocated;
+ struct percpu_counter tcp_sockets_allocated;
+ /* those two are read-mostly, leave them at the end */
+ long tcp_prot_mem[3];
+ int tcp_memory_pressure;
+};
+
+struct cg_proto *tcp_proto_cgroup(struct mem_cgroup *memcg);
+int tcp_init_cgroup(struct cgroup *cgrp, struct cgroup_subsys *ss);
+void tcp_destroy_cgroup(struct cgroup *cgrp, struct cgroup_subsys *ss);
+#endif /* _TCP_MEMCG_H */
--
cgit v1.2.3-70-g09d2
From 3aaabe2342c36bf48567b88fa78b819eee14bb5e Mon Sep 17 00:00:00 2001
From: Glauber Costa <glommer@parallels.com>
Date: Sun, 11 Dec 2011 21:47:06 +0000
Subject: tcp buffer limitation: per-cgroup limit
This patch uses the "tcp.limit_in_bytes" field of the kmem_cgroup to
effectively control the amount of kernel memory pinned by a cgroup.
This value is ignored in the root cgroup, and in all others,
caps the value specified by the admin in the net namespaces'
view of tcp_sysctl_mem.
If namespaces are being used, the admin is allowed to set a
value bigger than cgroup's maximum, the same way it is allowed
to set pretty much unlimited values in a real box.
Signed-off-by: Glauber Costa <glommer@parallels.com>
Reviewed-by: Hiroyouki Kamezawa <kamezawa.hiroyu@jp.fujitsu.com>
CC: David S. Miller <davem@davemloft.net>
CC: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
Documentation/cgroups/memory.txt | 1 +
include/net/tcp_memcontrol.h | 2 +
net/ipv4/sysctl_net_ipv4.c | 14 ++++
net/ipv4/tcp_memcontrol.c | 137 ++++++++++++++++++++++++++++++++++++++-
4 files changed, 152 insertions(+), 2 deletions(-)
(limited to 'include/net/tcp_memcontrol.h')
diff --git a/Documentation/cgroups/memory.txt b/Documentation/cgroups/memory.txt
index 687dea5bf1f..1c9779a74a2 100644
--- a/Documentation/cgroups/memory.txt
+++ b/Documentation/cgroups/memory.txt
@@ -78,6 +78,7 @@ Brief summary of control files.
memory.independent_kmem_limit # select whether or not kernel memory limits are
independent of user limits
+ memory.kmem.tcp.limit_in_bytes # set/show hard limit for tcp buf memory
1. History
diff --git a/include/net/tcp_memcontrol.h b/include/net/tcp_memcontrol.h
index 5f5e1582d76..3512082fa90 100644
--- a/include/net/tcp_memcontrol.h
+++ b/include/net/tcp_memcontrol.h
@@ -14,4 +14,6 @@ struct tcp_memcontrol {
struct cg_proto *tcp_proto_cgroup(struct mem_cgroup *memcg);
int tcp_init_cgroup(struct cgroup *cgrp, struct cgroup_subsys *ss);
void tcp_destroy_cgroup(struct cgroup *cgrp, struct cgroup_subsys *ss);
+unsigned long long tcp_max_memory(const struct mem_cgroup *memcg);
+void tcp_prot_mem(struct mem_cgroup *memcg, long val, int idx);
#endif /* _TCP_MEMCG_H */
diff --git a/net/ipv4/sysctl_net_ipv4.c b/net/ipv4/sysctl_net_ipv4.c
index bbd67abcb51..fe9bf915676 100644
--- a/net/ipv4/sysctl_net_ipv4.c
+++ b/net/ipv4/sysctl_net_ipv4.c
@@ -24,6 +24,7 @@
#include <net/cipso_ipv4.h>
#include <net/inet_frag.h>
#include <net/ping.h>
+#include <net/tcp_memcontrol.h>
static int zero;
static int tcp_retr1_max = 255;
@@ -182,6 +183,9 @@ static int ipv4_tcp_mem(ctl_table *ctl, int write,
int ret;
unsigned long vec[3];
struct net *net = current->nsproxy->net_ns;
+#ifdef CONFIG_CGROUP_MEM_RES_CTLR_KMEM
+ struct mem_cgroup *memcg;
+#endif
ctl_table tmp = {
.data = &vec,
@@ -198,6 +202,16 @@ static int ipv4_tcp_mem(ctl_table *ctl, int write,
if (ret)
return ret;
+#ifdef CONFIG_CGROUP_MEM_RES_CTLR_KMEM
+ rcu_read_lock();
+ memcg = mem_cgroup_from_task(current);
+
+ tcp_prot_mem(memcg, vec[0], 0);
+ tcp_prot_mem(memcg, vec[1], 1);
+ tcp_prot_mem(memcg, vec[2], 2);
+ rcu_read_unlock();
+#endif
+
net->ipv4.sysctl_tcp_mem[0] = vec[0];
net->ipv4.sysctl_tcp_mem[1] = vec[1];
net->ipv4.sysctl_tcp_mem[2] = vec[2];
diff --git a/net/ipv4/tcp_memcontrol.c b/net/ipv4/tcp_memcontrol.c
index bfb0c2b8df4..e3533903409 100644
--- a/net/ipv4/tcp_memcontrol.c
+++ b/net/ipv4/tcp_memcontrol.c
@@ -6,6 +6,19 @@
#include <linux/memcontrol.h>
#include <linux/module.h>
+static u64 tcp_cgroup_read(struct cgroup *cont, struct cftype *cft);
+static int tcp_cgroup_write(struct cgroup *cont, struct cftype *cft,
+ const char *buffer);
+
+static struct cftype tcp_files[] = {
+ {
+ .name = "kmem.tcp.limit_in_bytes",
+ .write_string = tcp_cgroup_write,
+ .read_u64 = tcp_cgroup_read,
+ .private = RES_LIMIT,
+ },
+};
+
static inline struct tcp_memcontrol *tcp_from_cgproto(struct cg_proto *cg_proto)
{
return container_of(cg_proto, struct tcp_memcontrol, cg_proto);
@@ -34,7 +47,7 @@ int tcp_init_cgroup(struct cgroup *cgrp, struct cgroup_subsys *ss)
cg_proto = tcp_prot.proto_cgroup(memcg);
if (!cg_proto)
- return 0;
+ goto create_files;
tcp = tcp_from_cgproto(cg_proto);
@@ -57,7 +70,9 @@ int tcp_init_cgroup(struct cgroup *cgrp, struct cgroup_subsys *ss)
cg_proto->sockets_allocated = &tcp->tcp_sockets_allocated;
cg_proto->memcg = memcg;
- return 0;
+create_files:
+ return cgroup_add_files(cgrp, ss, tcp_files,
+ ARRAY_SIZE(tcp_files));
}
EXPORT_SYMBOL(tcp_init_cgroup);
@@ -66,6 +81,7 @@ void tcp_destroy_cgroup(struct cgroup *cgrp, struct cgroup_subsys *ss)
struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp);
struct cg_proto *cg_proto;
struct tcp_memcontrol *tcp;
+ u64 val;
cg_proto = tcp_prot.proto_cgroup(memcg);
if (!cg_proto)
@@ -73,5 +89,122 @@ void tcp_destroy_cgroup(struct cgroup *cgrp, struct cgroup_subsys *ss)
tcp = tcp_from_cgproto(cg_proto);
percpu_counter_destroy(&tcp->tcp_sockets_allocated);
+
+ val = res_counter_read_u64(&tcp->tcp_memory_allocated, RES_USAGE);
+
+ if (val != RESOURCE_MAX)
+ jump_label_dec(&memcg_socket_limit_enabled);
}
EXPORT_SYMBOL(tcp_destroy_cgroup);
+
+static int tcp_update_limit(struct mem_cgroup *memcg, u64 val)
+{
+ struct net *net = current->nsproxy->net_ns;
+ struct tcp_memcontrol *tcp;
+ struct cg_proto *cg_proto;
+ u64 old_lim;
+ int i;
+ int ret;
+
+ cg_proto = tcp_prot.proto_cgroup(memcg);
+ if (!cg_proto)
+ return -EINVAL;
+
+ if (val > RESOURCE_MAX)
+ val = RESOURCE_MAX;
+
+ tcp = tcp_from_cgproto(cg_proto);
+
+ old_lim = res_counter_read_u64(&tcp->tcp_memory_allocated, RES_LIMIT);
+ ret = res_counter_set_limit(&tcp->tcp_memory_allocated, val);
+ if (ret)
+ return ret;
+
+ for (i = 0; i < 3; i++)
+ tcp->tcp_prot_mem[i] = min_t(long, val >> PAGE_SHIFT,
+ net->ipv4.sysctl_tcp_mem[i]);
+
+ if (val == RESOURCE_MAX && old_lim != RESOURCE_MAX)
+ jump_label_dec(&memcg_socket_limit_enabled);
+ else if (old_lim == RESOURCE_MAX && val != RESOURCE_MAX)
+ jump_label_inc(&memcg_socket_limit_enabled);
+
+ return 0;
+}
+
+static int tcp_cgroup_write(struct cgroup *cont, struct cftype *cft,
+ const char *buffer)
+{
+ struct mem_cgroup *memcg = mem_cgroup_from_cont(cont);
+ unsigned long long val;
+ int ret = 0;
+
+ switch (cft->private) {
+ case RES_LIMIT:
+ /* see memcontrol.c */
+ ret = res_counter_memparse_write_strategy(buffer, &val);
+ if (ret)
+ break;
+ ret = tcp_update_limit(memcg, val);
+ break;
+ default:
+ ret = -EINVAL;
+ break;
+ }
+ return ret;
+}
+
+static u64 tcp_read_stat(struct mem_cgroup *memcg, int type, u64 default_val)
+{
+ struct tcp_memcontrol *tcp;
+ struct cg_proto *cg_proto;
+
+ cg_proto = tcp_prot.proto_cgroup(memcg);
+ if (!cg_proto)
+ return default_val;
+
+ tcp = tcp_from_cgproto(cg_proto);
+ return res_counter_read_u64(&tcp->tcp_memory_allocated, type);
+}
+
+static u64 tcp_cgroup_read(struct cgroup *cont, struct cftype *cft)
+{
+ struct mem_cgroup *memcg = mem_cgroup_from_cont(cont);
+ u64 val;
+
+ switch (cft->private) {
+ case RES_LIMIT:
+ val = tcp_read_stat(memcg, RES_LIMIT, RESOURCE_MAX);
+ break;
+ default:
+ BUG();
+ }
+ return val;
+}
+
+unsigned long long tcp_max_memory(const struct mem_cgroup *memcg)
+{
+ struct tcp_memcontrol *tcp;
+ struct cg_proto *cg_proto;
+
+ cg_proto = tcp_prot.proto_cgroup((struct mem_cgroup *)memcg);
+ if (!cg_proto)
+ return 0;
+
+ tcp = tcp_from_cgproto(cg_proto);
+ return res_counter_read_u64(&tcp->tcp_memory_allocated, RES_LIMIT);
+}
+
+void tcp_prot_mem(struct mem_cgroup *memcg, long val, int idx)
+{
+ struct tcp_memcontrol *tcp;
+ struct cg_proto *cg_proto;
+
+ cg_proto = tcp_prot.proto_cgroup(memcg);
+ if (!cg_proto)
+ return;
+
+ tcp = tcp_from_cgproto(cg_proto);
+
+ tcp->tcp_prot_mem[idx] = val;
+}
--
cgit v1.2.3-70-g09d2