#define MEM_CGROUP_ID_SHIFT 16
#define MEM_CGROUP_ID_MAX USHRT_MAX
+struct mem_cgroup_id {
+ int id;
+ atomic_t ref;
+};
+
struct mem_cgroup_stat_cpu {
long count[MEMCG_NR_STAT];
unsigned long events[MEMCG_NR_EVENTS];
struct mem_cgroup {
struct cgroup_subsys_state css;
+ /* Private memcg ID. Used to ID objects that outlive the cgroup */
+ struct mem_cgroup_id id;
+
/* Accounted resources */
struct page_counter memory;
struct page_counter swap;
if (mem_cgroup_disabled())
return 0;
- return memcg->css.id;
-}
-
-/**
- * mem_cgroup_from_id - look up a memcg from an id
- * @id: the id to look up
- *
- * Caller must hold rcu_read_lock() and use css_tryget() as necessary.
- */
-static inline struct mem_cgroup *mem_cgroup_from_id(unsigned short id)
-{
- struct cgroup_subsys_state *css;
-
- css = css_from_id(id, &memory_cgrp_subsys);
- return mem_cgroup_from_css(css);
+ return memcg->id.id;
}
+struct mem_cgroup *mem_cgroup_from_id(unsigned short id);
/**
* parent_mem_cgroup - find the accounting parent of a memcg