blob: 899949bbb2f9362182e7fd28dc34833cca7de78e [file] [log] [blame]
/* memcontrol.h - Memory Controller
*
* Copyright IBM Corporation, 2007
* Author Balbir Singh <balbir@linux.vnet.ibm.com>
*
* Copyright 2007 OpenVZ SWsoft Inc
* Author: Pavel Emelianov <xemul@openvz.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#ifndef _LINUX_MEMCONTROL_H
#define _LINUX_MEMCONTROL_H
#include <linux/cgroup.h>
#include <linux/vm_event_item.h>
#include <linux/hardirq.h>
#include <linux/jump_label.h>
#include <linux/page_counter.h>
#include <linux/vmpressure.h>
#include <linux/eventfd.h>
#include <linux/mmzone.h>
#include <linux/writeback.h>
#include <linux/page-flags.h>
struct mem_cgroup;
struct page;
struct mm_struct;
struct kmem_cache;
/* Cgroup-specific page state, on top of universal node page state */
enum memcg_stat_item {
MEMCG_CACHE = NR_VM_NODE_STAT_ITEMS,
MEMCG_RSS,
MEMCG_RSS_HUGE,
MEMCG_SWAP,
MEMCG_SOCK,
/* XXX: why are these zone and not node counters? */
MEMCG_KERNEL_STACK_KB,
MEMCG_SLAB_RECLAIMABLE,
MEMCG_SLAB_UNRECLAIMABLE,
MEMCG_NR_STAT,
};
/* Cgroup-specific events, on top of universal VM events */
enum memcg_event_item {
MEMCG_LOW = NR_VM_EVENT_ITEMS,
MEMCG_HIGH,
MEMCG_MAX,
MEMCG_OOM,
MEMCG_NR_EVENTS,
};
struct mem_cgroup_reclaim_cookie {
pg_data_t *pgdat;
int priority;
unsigned int generation;
};
#ifdef CONFIG_MEMCG
#define MEM_CGROUP_ID_SHIFT 16
#define MEM_CGROUP_ID_MAX USHRT_MAX
struct mem_cgroup_id {
int id;
atomic_t ref;
};
/*
* Per memcg event counter is incremented at every pagein/pageout. With THP,
* it will be incremated by the number of pages. This counter is used for
* for trigger some periodic events. This is straightforward and better
* than using jiffies etc. to handle periodic memcg event.
*/
enum mem_cgroup_events_target {
MEM_CGROUP_TARGET_THRESH,
MEM_CGROUP_TARGET_SOFTLIMIT,
MEM_CGROUP_TARGET_NUMAINFO,
MEM_CGROUP_NTARGETS,
};
struct mem_cgroup_stat_cpu {
long count[MEMCG_NR_STAT];
unsigned long events[MEMCG_NR_EVENTS];
unsigned long nr_page_events;
unsigned long targets[MEM_CGROUP_NTARGETS];
};
struct mem_cgroup_reclaim_iter {
struct mem_cgroup *position;
/* scan generation, increased every round-trip */
unsigned int generation;
};
/*
* per-zone information in memory controller.
*/
struct mem_cgroup_per_node {
struct lruvec lruvec;
unsigned long lru_zone_size[MAX_NR_ZONES][NR_LRU_LISTS];
struct mem_cgroup_reclaim_iter iter[DEF_PRIORITY + 1];
struct rb_node tree_node; /* RB tree node */
unsigned long usage_in_excess;/* Set to the value by which */
/* the soft limit is exceeded*/
bool on_tree;
struct mem_cgroup *memcg; /* Back pointer, we cannot */
/* use container_of */
};
struct mem_cgroup_threshold {
struct eventfd_ctx *eventfd;
unsigned long threshold;
};
/* For threshold */
struct mem_cgroup_threshold_ary {
/* An array index points to threshold just below or equal to usage. */
int current_threshold;
/* Size of entries[] */
unsigned int size;
/* Array of thresholds */
struct mem_cgroup_threshold entries[0];
};
struct mem_cgroup_thresholds {
/* Primary thresholds array */
struct mem_cgroup_threshold_ary *primary;
/*
* Spare threshold array.
* This is needed to make mem_cgroup_unregister_event() "never fail".
* It must be able to store at least primary->size - 1 entries.
*/
struct mem_cgroup_threshold_ary *spare;
};
enum memcg_kmem_state {
KMEM_NONE,
KMEM_ALLOCATED,
KMEM_ONLINE,
};
/*
* The memory controller data structure. The memory controller controls both
* page cache and RSS per cgroup. We would eventually like to provide
* statistics based on the statistics developed by Rik Van Riel for clock-pro,
* to help the administrator determine what knobs to tune.
*/
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;
/* Legacy consumer-oriented counters */
struct page_counter memsw;
struct page_counter kmem;
struct page_counter tcpmem;
/* Normal memory consumption range */
unsigned long low;
unsigned long high;
/* Range enforcement for interrupt charges */
struct work_struct high_work;
unsigned long soft_limit;
/* vmpressure notifications */
struct vmpressure vmpressure;
/*
* Should the accounting and control be hierarchical, per subtree?
*/
bool use_hierarchy;
/* protected by memcg_oom_lock */
bool oom_lock;
int under_oom;
int swappiness;
/* OOM-Killer disable */
int oom_kill_disable;
/* handle for "memory.events" */
struct cgroup_file events_file;
/* protect arrays of thresholds */
struct mutex thresholds_lock;
/* thresholds for memory usage. RCU-protected */
struct mem_cgroup_thresholds thresholds;
/* thresholds for mem+swap usage. RCU-protected */
struct mem_cgroup_thresholds memsw_thresholds;
/* For oom notifier event fd */
struct list_head oom_notify;
/*
* Should we move charges of a task when a task is moved into this
* mem_cgroup ? And what type of charges should we move ?
*/
unsigned long move_charge_at_immigrate;
/*
* set > 0 if pages under this cgroup are moving to other cgroup.
*/
atomic_t moving_account;
/* taken only while moving_account > 0 */
spinlock_t move_lock;
struct task_struct *move_lock_task;
unsigned long move_lock_flags;
/*
* percpu counter.
*/
struct mem_cgroup_stat_cpu __percpu *stat;
unsigned long socket_pressure;
/* Legacy tcp memory accounting */
bool tcpmem_active;
int tcpmem_pressure;
#ifndef CONFIG_SLOB
/* Index in the kmem_cache->memcg_params.memcg_caches array */
int kmemcg_id;
enum memcg_kmem_state kmem_state;
struct list_head kmem_caches;
#endif
int last_scanned_node;
#if MAX_NUMNODES > 1
nodemask_t scan_nodes;
atomic_t numainfo_events;
atomic_t numainfo_updating;
#endif
#ifdef CONFIG_CGROUP_WRITEBACK
struct list_head cgwb_list;
struct wb_domain cgwb_domain;
#endif
/* List of events which userspace want to receive */
struct list_head event_list;
spinlock_t event_list_lock;
struct mem_cgroup_per_node *nodeinfo[0];
/* WARNING: nodeinfo must be the last member here */
};
extern struct mem_cgroup *root_mem_cgroup;
static inline bool mem_cgroup_disabled(void)
{
return !cgroup_subsys_enabled(memory_cgrp_subsys);
}
static inline void mem_cgroup_event(struct mem_cgroup *memcg,
enum memcg_event_item event)
{
this_cpu_inc(memcg->stat->events[event]);
cgroup_file_notify(&memcg->events_file);
}
bool mem_cgroup_low(struct mem_cgroup *root, struct mem_cgroup *memcg);
int mem_cgroup_try_charge(struct page *page, struct mm_struct *mm,
gfp_t gfp_mask, struct mem_cgroup **memcgp,
bool compound);
void mem_cgroup_commit_charge(struct page *page, struct mem_cgroup *memcg,
bool lrucare, bool compound);
void mem_cgroup_cancel_charge(struct page *page, struct mem_cgroup *memcg,
bool compound);
void mem_cgroup_uncharge(struct page *page);
void mem_cgroup_uncharge_list(struct list_head *page_list);
void mem_cgroup_migrate(struct page *oldpage, struct page *newpage);
static struct mem_cgroup_per_node *
mem_cgroup_nodeinfo(struct mem_cgroup *memcg, int nid)
{
return memcg->nodeinfo[nid];
}
/**
* mem_cgroup_lruvec - get the lru list vector for a node or a memcg zone
* @node: node of the wanted lruvec
* @memcg: memcg of the wanted lruvec
*
* Returns the lru list vector holding pages for a given @node or a given
* @memcg and @zone. This can be the node lruvec, if the memory controller
* is disabled.
*/
static inline struct lruvec *mem_cgroup_lruvec(struct pglist_data *pgdat,
struct mem_cgroup *memcg)
{
struct mem_cgroup_per_node *mz;
struct lruvec *lruvec;
if (mem_cgroup_disabled()) {
lruvec = node_lruvec(pgdat);
goto out;
}
mz = mem_cgroup_nodeinfo(memcg, pgdat->node_id);
lruvec = &mz->lruvec;
out:
/*
* Since a node can be onlined after the mem_cgroup was created,
* we have to be prepared to initialize lruvec->pgdat here;
* and if offlined then reonlined, we need to reinitialize it.
*/
if (unlikely(lruvec->pgdat != pgdat))
lruvec->pgdat = pgdat;
return lruvec;
}
struct lruvec *mem_cgroup_page_lruvec(struct page *, struct pglist_data *);
bool task_in_mem_cgroup(struct task_struct *task, struct mem_cgroup *memcg);
struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p);
static inline
struct mem_cgroup *mem_cgroup_from_css(struct cgroup_subsys_state *css){
return css ? container_of(css, struct mem_cgroup, css) : NULL;
}
#define mem_cgroup_from_counter(counter, member) \
container_of(counter, struct mem_cgroup, member)
struct mem_cgroup *mem_cgroup_iter(struct mem_cgroup *,
struct mem_cgroup *,
struct mem_cgroup_reclaim_cookie *);
void mem_cgroup_iter_break(struct mem_cgroup *, struct mem_cgroup *);
int mem_cgroup_scan_tasks(struct mem_cgroup *,
int (*)(struct task_struct *, void *), void *);
static inline unsigned short mem_cgroup_id(struct mem_cgroup *memcg)
{
if (mem_cgroup_disabled())
return 0;
return memcg->id.id;
}
struct mem_cgroup *mem_cgroup_from_id(unsigned short id);
/**
* parent_mem_cgroup - find the accounting parent of a memcg
* @memcg: memcg whose parent to find
*
* Returns the parent memcg, or NULL if this is the root or the memory
* controller is in legacy no-hierarchy mode.
*/
static inline struct mem_cgroup *parent_mem_cgroup(struct mem_cgroup *memcg)
{
if (!memcg->memory.parent)
return NULL;
return mem_cgroup_from_counter(memcg->memory.parent, memory);
}
static inline bool mem_cgroup_is_descendant(struct mem_cgroup *memcg,
struct mem_cgroup *root)
{
if (root == memcg)
return true;
if (!root->use_hierarchy)
return false;
return cgroup_is_descendant(memcg->css.cgroup, root->css.cgroup);
}
static inline bool mm_match_cgroup(struct mm_struct *mm,
struct mem_cgroup *memcg)
{
struct mem_cgroup *task_memcg;
bool match = false;
rcu_read_lock();
task_memcg = mem_cgroup_from_task(rcu_dereference(mm->owner));
if (task_memcg)
match = mem_cgroup_is_descendant(task_memcg, memcg);
rcu_read_unlock();
return match;
}
struct cgroup_subsys_state *mem_cgroup_css_from_page(struct page *page);
ino_t page_cgroup_ino(struct page *page);
static inline bool mem_cgroup_online(struct mem_cgroup *memcg)
{
if (mem_cgroup_disabled())
return true;
return !!(memcg->css.flags & CSS_ONLINE);
}
/*
* For memory reclaim.
*/
int mem_cgroup_select_victim_node(struct mem_cgroup *memcg);
void mem_cgroup_update_lru_size(struct lruvec *lruvec, enum lru_list lru,
int zid, int nr_pages);
unsigned long mem_cgroup_node_nr_lru_pages(struct mem_cgroup *memcg,
int nid, unsigned int lru_mask);
static inline
unsigned long mem_cgroup_get_lru_size(struct lruvec *lruvec, enum lru_list lru)
{
struct mem_cgroup_per_node *mz;
unsigned long nr_pages = 0;
int zid;
mz = container_of(lruvec, struct mem_cgroup_per_node, lruvec);
for (zid = 0; zid < MAX_NR_ZONES; zid++)
nr_pages += mz->lru_zone_size[zid][lru];
return nr_pages;
}
static inline
unsigned long mem_cgroup_get_zone_lru_size(struct lruvec *lruvec,
enum lru_list lru, int zone_idx)
{
struct mem_cgroup_per_node *mz;
mz = container_of(lruvec, struct mem_cgroup_per_node, lruvec);
return mz->lru_zone_size[zone_idx][lru];
}
void mem_cgroup_handle_over_high(void);
unsigned long mem_cgroup_get_limit(struct mem_cgroup *memcg);
void mem_cgroup_print_oom_info(struct mem_cgroup *memcg,
struct task_struct *p);
static inline void mem_cgroup_oom_enable(void)
{
WARN_ON(current->memcg_may_oom);
current->memcg_may_oom = 1;
}
static inline void mem_cgroup_oom_disable(void)
{
WARN_ON(!current->memcg_may_oom);
current->memcg_may_oom = 0;
}
static inline bool task_in_memcg_oom(struct task_struct *p)
{
return p->memcg_in_oom;
}
bool mem_cgroup_oom_synchronize(bool wait);
#ifdef CONFIG_MEMCG_SWAP
extern int do_swap_account;
#endif
void lock_page_memcg(struct page *page);
void unlock_page_memcg(struct page *page);
static inline unsigned long memcg_page_state(struct mem_cgroup *memcg,
enum memcg_stat_item idx)
{
long val = 0;
int cpu;
for_each_possible_cpu(cpu)
val += per_cpu(memcg->stat->count[idx], cpu);
if (val < 0)
val = 0;
return val;
}
static inline void mod_memcg_state(struct mem_cgroup *memcg,
enum memcg_stat_item idx, int val)
{
if (!mem_cgroup_disabled())
this_cpu_add(memcg->stat->count[idx], val);
}
static inline void inc_memcg_state(struct mem_cgroup *memcg,
enum memcg_stat_item idx)
{
mod_memcg_state(memcg, idx, 1);
}
static inline void dec_memcg_state(struct mem_cgroup *memcg,
enum memcg_stat_item idx)
{
mod_memcg_state(memcg, idx, -1);
}
/**
* mod_memcg_page_state - update page state statistics
* @page: the page
* @idx: page state item to account
* @val: number of pages (positive or negative)
*
* The @page must be locked or the caller must use lock_page_memcg()
* to prevent double accounting when the page is concurrently being
* moved to another memcg:
*
* lock_page(page) or lock_page_memcg(page)
* if (TestClearPageState(page))
* mod_memcg_page_state(page, state, -1);
* unlock_page(page) or unlock_page_memcg(page)
*
* Kernel pages are an exception to this, since they'll never move.
*/
static inline void mod_memcg_page_state(struct page *page,
enum memcg_stat_item idx, int val)
{
if (page->mem_cgroup)
mod_memcg_state(page->mem_cgroup, idx, val);
}
static inline void inc_memcg_page_state(struct page *page,
enum memcg_stat_item idx)
{
mod_memcg_page_state(page, idx, 1);
}
static inline void dec_memcg_page_state(struct page *page,
enum memcg_stat_item idx)
{
mod_memcg_page_state(page, idx, -1);
}
unsigned long mem_cgroup_soft_limit_reclaim(pg_data_t *pgdat, int order,
gfp_t gfp_mask,
unsigned long *total_scanned);
static inline void mem_cgroup_count_vm_event(struct mm_struct *mm,
enum vm_event_item idx)
{
struct mem_cgroup *memcg;
if (mem_cgroup_disabled())
return;
rcu_read_lock();
memcg = mem_cgroup_from_task(rcu_dereference(mm->owner));
if (likely(memcg))
this_cpu_inc(memcg->stat->events[idx]);
rcu_read_unlock();
}
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
void mem_cgroup_split_huge_fixup(struct page *head);
#endif
#else /* CONFIG_MEMCG */
#define MEM_CGROUP_ID_SHIFT 0
#define MEM_CGROUP_ID_MAX 0
struct mem_cgroup;
static inline bool mem_cgroup_disabled(void)
{
return true;
}
static inline void mem_cgroup_event(struct mem_cgroup *memcg,
enum memcg_event_item event)
{
}
static inline bool mem_cgroup_low(struct mem_cgroup *root,
struct mem_cgroup *memcg)
{
return false;
}
static inline int mem_cgroup_try_charge(struct page *page, struct mm_struct *mm,
gfp_t gfp_mask,
struct mem_cgroup **memcgp,
bool compound)
{
*memcgp = NULL;
return 0;
}
static inline void mem_cgroup_commit_charge(struct page *page,
struct mem_cgroup *memcg,
bool lrucare, bool compound)
{
}
static inline void mem_cgroup_cancel_charge(struct page *page,
struct mem_cgroup *memcg,
bool compound)
{
}
static inline void mem_cgroup_uncharge(struct page *page)
{
}
static inline void mem_cgroup_uncharge_list(struct list_head *page_list)
{
}
static inline void mem_cgroup_migrate(struct page *old, struct page *new)
{
}
static inline struct lruvec *mem_cgroup_lruvec(struct pglist_data *pgdat,
struct mem_cgroup *memcg)
{
return node_lruvec(pgdat);
}
static inline struct lruvec *mem_cgroup_page_lruvec(struct page *page,
struct pglist_data *pgdat)
{
return &pgdat->lruvec;
}
static inline bool mm_match_cgroup(struct mm_struct *mm,
struct mem_cgroup *memcg)
{
return true;
}
static inline bool task_in_mem_cgroup(struct task_struct *task,
const struct mem_cgroup *memcg)
{
return true;
}
static inline struct mem_cgroup *
mem_cgroup_iter(struct mem_cgroup *root,
struct mem_cgroup *prev,
struct mem_cgroup_reclaim_cookie *reclaim)
{
return NULL;
}
static inline void mem_cgroup_iter_break(struct mem_cgroup *root,
struct mem_cgroup *prev)
{
}
static inline int mem_cgroup_scan_tasks(struct mem_cgroup *memcg,
int (*fn)(struct task_struct *, void *), void *arg)
{
return 0;
}
static inline unsigned short mem_cgroup_id(struct mem_cgroup *memcg)
{
return 0;
}
static inline struct mem_cgroup *mem_cgroup_from_id(unsigned short id)
{
WARN_ON_ONCE(id);
/* XXX: This should always return root_mem_cgroup */
return NULL;
}
static inline bool mem_cgroup_online(struct mem_cgroup *memcg)
{
return true;
}
static inline unsigned long
mem_cgroup_get_lru_size(struct lruvec *lruvec, enum lru_list lru)
{
return 0;
}
static inline
unsigned long mem_cgroup_get_zone_lru_size(struct lruvec *lruvec,
enum lru_list lru, int zone_idx)
{
return 0;
}
static inline unsigned long
mem_cgroup_node_nr_lru_pages(struct mem_cgroup *memcg,
int nid, unsigned int lru_mask)
{
return 0;
}
static inline unsigned long mem_cgroup_get_limit(struct mem_cgroup *memcg)
{
return 0;
}
static inline void
mem_cgroup_print_oom_info(struct mem_cgroup *memcg, struct task_struct *p)
{
}
static inline void lock_page_memcg(struct page *page)
{
}
static inline void unlock_page_memcg(struct page *page)
{
}
static inline void mem_cgroup_handle_over_high(void)
{
}
static inline void mem_cgroup_oom_enable(void)
{
}
static inline void mem_cgroup_oom_disable(void)
{
}
static inline bool task_in_memcg_oom(struct task_struct *p)
{
return false;
}
static inline bool mem_cgroup_oom_synchronize(bool wait)
{
return false;
}
static inline unsigned long memcg_page_state(struct mem_cgroup *memcg,
enum memcg_stat_item idx)
{
return 0;
}
static inline void mod_memcg_state(struct mem_cgroup *memcg,
enum memcg_stat_item idx,
int nr)
{
}
static inline void inc_memcg_state(struct mem_cgroup *memcg,
enum memcg_stat_item idx)
{
}
static inline void dec_memcg_state(struct mem_cgroup *memcg,
enum memcg_stat_item idx)
{
}
static inline void mod_memcg_page_state(struct page *page,
enum memcg_stat_item idx,
int nr)
{
}
static inline void inc_memcg_page_state(struct page *page,
enum memcg_stat_item idx)
{
}
static inline void dec_memcg_page_state(struct page *page,
enum memcg_stat_item idx)
{
}
static inline
unsigned long mem_cgroup_soft_limit_reclaim(pg_data_t *pgdat, int order,
gfp_t gfp_mask,
unsigned long *total_scanned)
{
return 0;
}
static inline void mem_cgroup_split_huge_fixup(struct page *head)
{
}
static inline
void mem_cgroup_count_vm_event(struct mm_struct *mm, enum vm_event_item idx)
{
}
#endif /* CONFIG_MEMCG */
#ifdef CONFIG_CGROUP_WRITEBACK
struct list_head *mem_cgroup_cgwb_list(struct mem_cgroup *memcg);
struct wb_domain *mem_cgroup_wb_domain(struct bdi_writeback *wb);
void mem_cgroup_wb_stats(struct bdi_writeback *wb, unsigned long *pfilepages,
unsigned long *pheadroom, unsigned long *pdirty,
unsigned long *pwriteback);
#else /* CONFIG_CGROUP_WRITEBACK */
static inline struct wb_domain *mem_cgroup_wb_domain(struct bdi_writeback *wb)
{
return NULL;
}
static inline void mem_cgroup_wb_stats(struct bdi_writeback *wb,
unsigned long *pfilepages,
unsigned long *pheadroom,
unsigned long *pdirty,
unsigned long *pwriteback)
{
}
#endif /* CONFIG_CGROUP_WRITEBACK */
struct sock;
bool mem_cgroup_charge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages);
void mem_cgroup_uncharge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages);
#ifdef CONFIG_MEMCG
extern struct static_key_false memcg_sockets_enabled_key;
#define mem_cgroup_sockets_enabled static_branch_unlikely(&memcg_sockets_enabled_key)
void mem_cgroup_sk_alloc(struct sock *sk);
void mem_cgroup_sk_free(struct sock *sk);
static inline bool mem_cgroup_under_socket_pressure(struct mem_cgroup *memcg)
{
if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) && memcg->tcpmem_pressure)
return true;
do {
if (time_before(jiffies, memcg->socket_pressure))
return true;
} while ((memcg = parent_mem_cgroup(memcg)));
return false;
}
#else
#define mem_cgroup_sockets_enabled 0
static inline void mem_cgroup_sk_alloc(struct sock *sk) { };
static inline void mem_cgroup_sk_free(struct sock *sk) { };
static inline bool mem_cgroup_under_socket_pressure(struct mem_cgroup *memcg)
{
return false;
}
#endif
struct kmem_cache *memcg_kmem_get_cache(struct kmem_cache *cachep);
void memcg_kmem_put_cache(struct kmem_cache *cachep);
int memcg_kmem_charge_memcg(struct page *page, gfp_t gfp, int order,
struct mem_cgroup *memcg);
int memcg_kmem_charge(struct page *page, gfp_t gfp, int order);
void memcg_kmem_uncharge(struct page *page, int order);
#if defined(CONFIG_MEMCG) && !defined(CONFIG_SLOB)
extern struct static_key_false memcg_kmem_enabled_key;
extern struct workqueue_struct *memcg_kmem_cache_wq;
extern int memcg_nr_cache_ids;
void memcg_get_cache_ids(void);
void memcg_put_cache_ids(void);
/*
* Helper macro to loop through all memcg-specific caches. Callers must still
* check if the cache is valid (it is either valid or NULL).
* the slab_mutex must be held when looping through those caches
*/
#define for_each_memcg_cache_index(_idx) \
for ((_idx) = 0; (_idx) < memcg_nr_cache_ids; (_idx)++)
static inline bool memcg_kmem_enabled(void)
{
return static_branch_unlikely(&memcg_kmem_enabled_key);
}
/*
* helper for accessing a memcg's index. It will be used as an index in the
* child cache array in kmem_cache, and also to derive its name. This function
* will return -1 when this is not a kmem-limited memcg.
*/
static inline int memcg_cache_id(struct mem_cgroup *memcg)
{
return memcg ? memcg->kmemcg_id : -1;
}
/**
* memcg_kmem_update_page_stat - update kmem page state statistics
* @page: the page
* @idx: page state item to account
* @val: number of pages (positive or negative)
*/
static inline void memcg_kmem_update_page_stat(struct page *page,
enum memcg_stat_item idx, int val)
{
if (memcg_kmem_enabled() && page->mem_cgroup)
this_cpu_add(page->mem_cgroup->stat->count[idx], val);
}
#else
#define for_each_memcg_cache_index(_idx) \
for (; NULL; )
static inline bool memcg_kmem_enabled(void)
{
return false;
}
static inline int memcg_cache_id(struct mem_cgroup *memcg)
{
return -1;
}
static inline void memcg_get_cache_ids(void)
{
}
static inline void memcg_put_cache_ids(void)
{
}
static inline void memcg_kmem_update_page_stat(struct page *page,
enum memcg_stat_item idx, int val)
{
}
#endif /* CONFIG_MEMCG && !CONFIG_SLOB */
#endif /* _LINUX_MEMCONTROL_H */