From 0850f0f5c54261a6236f013e8bac154bcce424d6 Mon Sep 17 00:00:00 2001 From: Glauber Costa Date: Sun, 11 Dec 2011 21:47:09 +0000 Subject: [PATCH] Display maximum tcp memory allocation in kmem cgroup This patch introduces kmem.tcp.max_usage_in_bytes file, living in the kmem_cgroup filesystem. The root cgroup will display a value equal to RESOURCE_MAX. This is to avoid introducing any locking schemes in the network paths when cgroups are not being actively used. All others, will see the maximum memory ever used by this cgroup. Signed-off-by: Glauber Costa Reviewed-by: Hiroyouki Kamezawa CC: David S. Miller CC: Eric W. Biederman Signed-off-by: David S. Miller --- net/ipv4/tcp_memcontrol.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/net/ipv4/tcp_memcontrol.c b/net/ipv4/tcp_memcontrol.c index d438fba..171d7b64 100644 --- a/net/ipv4/tcp_memcontrol.c +++ b/net/ipv4/tcp_memcontrol.c @@ -29,6 +29,12 @@ static struct cftype tcp_files[] = { .trigger = tcp_cgroup_reset, .read_u64 = tcp_cgroup_read, }, + { + .name = "kmem.tcp.max_usage_in_bytes", + .private = RES_MAX_USAGE, + .trigger = tcp_cgroup_reset, + .read_u64 = tcp_cgroup_read, + }, }; static inline struct tcp_memcontrol *tcp_from_cgproto(struct cg_proto *cg_proto) @@ -205,7 +211,8 @@ static u64 tcp_cgroup_read(struct cgroup *cont, struct cftype *cft) val = tcp_read_usage(memcg); break; case RES_FAILCNT: - val = tcp_read_stat(memcg, RES_FAILCNT, 0); + case RES_MAX_USAGE: + val = tcp_read_stat(memcg, cft->private, 0); break; default: BUG(); @@ -226,6 +233,9 @@ static int tcp_cgroup_reset(struct cgroup *cont, unsigned int event) tcp = tcp_from_cgproto(cg_proto); switch (event) { + case RES_MAX_USAGE: + res_counter_reset_max(&tcp->tcp_memory_allocated); + break; case RES_FAILCNT: res_counter_reset_failcnt(&tcp->tcp_memory_allocated); break; -- 2.7.4