From e1aab161e0135aafcd439be20b4f35e4b0922d95 Mon Sep 17 00:00:00 2001 From: Glauber Costa Date: Sun, 11 Dec 2011 21:47:03 +0000 Subject: socket: initial cgroup code. The goal of this work is to move the memory pressure tcp controls to a cgroup, instead of just relying on global conditions. To avoid excessive overhead in the network fast paths, the code that accounts allocated memory to a cgroup is hidden inside a static_branch(). This branch is patched out until the first non-root cgroup is created. So when nobody is using cgroups, even if it is mounted, no significant performance penalty should be seen. This patch handles the generic part of the code, and has nothing tcp-specific. Signed-off-by: Glauber Costa Reviewed-by: KAMEZAWA Hiroyuki CC: Kirill A. Shutemov CC: David S. Miller CC: Eric W. Biederman CC: Eric Dumazet Signed-off-by: David S. Miller --- mm/memcontrol.c | 46 ++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 44 insertions(+), 2 deletions(-) (limited to 'mm') diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 9fbcff71245e..3de3901ae0a7 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -379,7 +379,48 @@ enum mem_type { static void mem_cgroup_get(struct mem_cgroup *memcg); static void mem_cgroup_put(struct mem_cgroup *memcg); -static struct mem_cgroup *parent_mem_cgroup(struct mem_cgroup *memcg); + +/* Writing them here to avoid exposing memcg's inner layout */ +#ifdef CONFIG_CGROUP_MEM_RES_CTLR_KMEM +#ifdef CONFIG_INET +#include + +static bool mem_cgroup_is_root(struct mem_cgroup *memcg); +void sock_update_memcg(struct sock *sk) +{ + /* A socket spends its whole life in the same cgroup */ + if (sk->sk_cgrp) { + WARN_ON(1); + return; + } + if (static_branch(&memcg_socket_limit_enabled)) { + struct mem_cgroup *memcg; + + BUG_ON(!sk->sk_prot->proto_cgroup); + + rcu_read_lock(); + memcg = mem_cgroup_from_task(current); + if (!mem_cgroup_is_root(memcg)) { + mem_cgroup_get(memcg); + sk->sk_cgrp = sk->sk_prot->proto_cgroup(memcg); + } + rcu_read_unlock(); + } +} +EXPORT_SYMBOL(sock_update_memcg); + +void sock_release_memcg(struct sock *sk) +{ + if (static_branch(&memcg_socket_limit_enabled) && sk->sk_cgrp) { + struct mem_cgroup *memcg; + WARN_ON(!sk->sk_cgrp->memcg); + memcg = sk->sk_cgrp->memcg; + mem_cgroup_put(memcg); + } +} +#endif /* CONFIG_INET */ +#endif /* CONFIG_CGROUP_MEM_RES_CTLR_KMEM */ + static void drain_all_stock_async(struct mem_cgroup *memcg); static struct mem_cgroup_per_zone * @@ -4932,12 +4973,13 @@ static void mem_cgroup_put(struct mem_cgroup *memcg) /* * Returns the parent mem_cgroup in memcgroup hierarchy with hierarchy enabled. */ -static struct mem_cgroup *parent_mem_cgroup(struct mem_cgroup *memcg) +struct mem_cgroup *parent_mem_cgroup(struct mem_cgroup *memcg) { if (!memcg->res.parent) return NULL; return mem_cgroup_from_res_counter(memcg->res.parent, res); } +EXPORT_SYMBOL(parent_mem_cgroup); #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP static void __init enable_swap_cgroup(void) -- cgit v1.2.3