[PATCH v4 7/8] Display current tcp memory allocation in kmem cgroup

Glauber Costa
2011-10-03T10:20:52Z

This patch introduces kmem.tcp_current_memory file, living in the
kmem_cgroup filesystem. It is a simple read-only file that displays the
amount of kernel memory currently consumed by the cgroup.

Signed-off-by: Glauber Costa <glommer@parallels.com>
CC: David S. Miller <davem@davemloft.net>
CC: Hiroyouki Kamezawa <kamezawa.hiroyu@jp.fujitsu.com>
CC: Eric W. Biederman <ebiederm@xmission.com>
---
Documentation/cgroups/memory.txt | 1 +
mm/memcontrol.c | 11 +++++++++++
2 files changed, 12 insertions(+), 0 deletions(-)

diff --git a/Documentation/cgroups/memory.txt b/Documentation/cgroups/memory.txt
index 1ffde3e..f5a539d 100644
--- a/Documentation/cgroups/memory.txt
+++ b/Documentation/cgroups/memory.txt
@@ -79,6 +79,7 @@ Brief summary of control files.
memory.independent_kmem_limit # select whether or not kernel memory limits are
independent of user limits
memory.kmem.tcp.max_memory # set/show hard limit for tcp buf memory
+ memory.kmem.tcp.current_memory # show current tcp buf memory allocation

1. History

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 38b66e9..3b38d0a 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -496,12 +496,23 @@ static u64 tcp_read_maxmem(struct cgroup *cgrp, struct cftype *cft)
return memcg->tcp.tcp_max_memory;
}

+static u64 tcp_read_curmem(struct cgroup *cgrp, struct cftype *cft)
+{
+ struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp);
+
+ return atomic_long_read(&memcg->tcp.tcp_memory_allocated);
+}
+
static struct cftype tcp_files[] = {
{
.name = "kmem.tcp.max_memory",
.write_u64 = tcp_write_maxmem,
.read_u64 = tcp_read_maxmem,
},
+ {
+ .name = "kmem.tcp.current_memory",
+ .read_u64 = tcp_read_curmem,
+ },
};

static void tcp_create_cgroup(struct mem_cgroup *cg, struct cgroup_subsys *ss)
--
1.7.6