swh:1:snp:c2847dfd741eae21606027cf29250d1ebcd63fb4
Tip revision: 836dc9e3fbbab0c30aa6e664417225f5c1fb1c39 authored by Linus Torvalds on 08 February 2013, 21:20:39 UTC
Linux 3.8-rc7
Linux 3.8-rc7
Tip revision: 836dc9e
memcontrol.h
/* 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>
struct mem_cgroup;
struct page_cgroup;
struct page;
struct mm_struct;
struct kmem_cache;
/* Stats that can be updated by kernel. */
enum mem_cgroup_page_stat_item {
MEMCG_NR_FILE_MAPPED, /* # of pages charged as file rss */
};
struct mem_cgroup_reclaim_cookie {
struct zone *zone;
int priority;
unsigned int generation;
};
#ifdef CONFIG_MEMCG
/*
* All "charge" functions with gfp_mask should use GFP_KERNEL or
* (gfp_mask & GFP_RECLAIM_MASK). In current implementatin, memcg doesn't
* alloc memory but reclaims memory from all available zones. So, "where I want
* memory from" bits of gfp_mask has no meaning. So any bits of that field is
* available but adding a rule is better. charge functions' gfp_mask should
* be set to GFP_KERNEL or gfp_mask & GFP_RECLAIM_MASK for avoiding ambiguous
* codes.
* (Of course, if memcg does memory allocation in future, GFP_KERNEL is sane.)
*/
extern int mem_cgroup_newpage_charge(struct page *page, struct mm_struct *mm,
gfp_t gfp_mask);
/* for swap handling */
extern int mem_cgroup_try_charge_swapin(struct mm_struct *mm,
struct page *page, gfp_t mask, struct mem_cgroup **memcgp);
extern void mem_cgroup_commit_charge_swapin(struct page *page,
struct mem_cgroup *memcg);
extern void mem_cgroup_cancel_charge_swapin(struct mem_cgroup *memcg);
extern int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm,
gfp_t gfp_mask);
struct lruvec *mem_cgroup_zone_lruvec(struct zone *, struct mem_cgroup *);
struct lruvec *mem_cgroup_page_lruvec(struct page *, struct zone *);
/* For coalescing uncharge for reducing memcg' overhead*/
extern void mem_cgroup_uncharge_start(void);
extern void mem_cgroup_uncharge_end(void);
extern void mem_cgroup_uncharge_page(struct page *page);
extern void mem_cgroup_uncharge_cache_page(struct page *page);
bool __mem_cgroup_same_or_subtree(const struct mem_cgroup *root_memcg,
struct mem_cgroup *memcg);
int task_in_mem_cgroup(struct task_struct *task, const struct mem_cgroup *memcg);
extern struct mem_cgroup *try_get_mem_cgroup_from_page(struct page *page);
extern struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p);
extern struct mem_cgroup *try_get_mem_cgroup_from_mm(struct mm_struct *mm);
extern struct mem_cgroup *parent_mem_cgroup(struct mem_cgroup *memcg);
extern struct mem_cgroup *mem_cgroup_from_cont(struct cgroup *cont);
static inline
bool mm_match_cgroup(const struct mm_struct *mm, const struct mem_cgroup *memcg)
{
struct mem_cgroup *task_memcg;
bool match;
rcu_read_lock();
task_memcg = mem_cgroup_from_task(rcu_dereference(mm->owner));
match = __mem_cgroup_same_or_subtree(memcg, task_memcg);
rcu_read_unlock();
return match;
}
extern struct cgroup_subsys_state *mem_cgroup_css(struct mem_cgroup *memcg);
extern void
mem_cgroup_prepare_migration(struct page *page, struct page *newpage,
struct mem_cgroup **memcgp);
extern void mem_cgroup_end_migration(struct mem_cgroup *memcg,
struct page *oldpage, struct page *newpage, bool migration_ok);
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 *);
/*
* For memory reclaim.
*/
int mem_cgroup_inactive_anon_is_low(struct lruvec *lruvec);
int mem_cgroup_inactive_file_is_low(struct lruvec *lruvec);
int mem_cgroup_select_victim_node(struct mem_cgroup *memcg);
unsigned long mem_cgroup_get_lru_size(struct lruvec *lruvec, enum lru_list);
void mem_cgroup_update_lru_size(struct lruvec *, enum lru_list, int);
extern void mem_cgroup_print_oom_info(struct mem_cgroup *memcg,
struct task_struct *p);
extern void mem_cgroup_replace_page_cache(struct page *oldpage,
struct page *newpage);
#ifdef CONFIG_MEMCG_SWAP
extern int do_swap_account;
#endif
static inline bool mem_cgroup_disabled(void)
{
if (mem_cgroup_subsys.disabled)
return true;
return false;
}
void __mem_cgroup_begin_update_page_stat(struct page *page, bool *locked,
unsigned long *flags);
extern atomic_t memcg_moving;
static inline void mem_cgroup_begin_update_page_stat(struct page *page,
bool *locked, unsigned long *flags)
{
if (mem_cgroup_disabled())
return;
rcu_read_lock();
*locked = false;
if (atomic_read(&memcg_moving))
__mem_cgroup_begin_update_page_stat(page, locked, flags);
}
void __mem_cgroup_end_update_page_stat(struct page *page,
unsigned long *flags);
static inline void mem_cgroup_end_update_page_stat(struct page *page,
bool *locked, unsigned long *flags)
{
if (mem_cgroup_disabled())
return;
if (*locked)
__mem_cgroup_end_update_page_stat(page, flags);
rcu_read_unlock();
}
void mem_cgroup_update_page_stat(struct page *page,
enum mem_cgroup_page_stat_item idx,
int val);
static inline void mem_cgroup_inc_page_stat(struct page *page,
enum mem_cgroup_page_stat_item idx)
{
mem_cgroup_update_page_stat(page, idx, 1);
}
static inline void mem_cgroup_dec_page_stat(struct page *page,
enum mem_cgroup_page_stat_item idx)
{
mem_cgroup_update_page_stat(page, idx, -1);
}
unsigned long mem_cgroup_soft_limit_reclaim(struct zone *zone, int order,
gfp_t gfp_mask,
unsigned long *total_scanned);
void __mem_cgroup_count_vm_event(struct mm_struct *mm, enum vm_event_item idx);
static inline void mem_cgroup_count_vm_event(struct mm_struct *mm,
enum vm_event_item idx)
{
if (mem_cgroup_disabled())
return;
__mem_cgroup_count_vm_event(mm, idx);
}
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
void mem_cgroup_split_huge_fixup(struct page *head);
#endif
#ifdef CONFIG_DEBUG_VM
bool mem_cgroup_bad_page_check(struct page *page);
void mem_cgroup_print_bad_page(struct page *page);
#endif
#else /* CONFIG_MEMCG */
struct mem_cgroup;
static inline int mem_cgroup_newpage_charge(struct page *page,
struct mm_struct *mm, gfp_t gfp_mask)
{
return 0;
}
static inline int mem_cgroup_cache_charge(struct page *page,
struct mm_struct *mm, gfp_t gfp_mask)
{
return 0;
}
static inline int mem_cgroup_try_charge_swapin(struct mm_struct *mm,
struct page *page, gfp_t gfp_mask, struct mem_cgroup **memcgp)
{
return 0;
}
static inline void mem_cgroup_commit_charge_swapin(struct page *page,
struct mem_cgroup *memcg)
{
}
static inline void mem_cgroup_cancel_charge_swapin(struct mem_cgroup *memcg)
{
}
static inline void mem_cgroup_uncharge_start(void)
{
}
static inline void mem_cgroup_uncharge_end(void)
{
}
static inline void mem_cgroup_uncharge_page(struct page *page)
{
}
static inline void mem_cgroup_uncharge_cache_page(struct page *page)
{
}
static inline struct lruvec *mem_cgroup_zone_lruvec(struct zone *zone,
struct mem_cgroup *memcg)
{
return &zone->lruvec;
}
static inline struct lruvec *mem_cgroup_page_lruvec(struct page *page,
struct zone *zone)
{
return &zone->lruvec;
}
static inline struct mem_cgroup *try_get_mem_cgroup_from_page(struct page *page)
{
return NULL;
}
static inline struct mem_cgroup *try_get_mem_cgroup_from_mm(struct mm_struct *mm)
{
return NULL;
}
static inline bool mm_match_cgroup(struct mm_struct *mm,
struct mem_cgroup *memcg)
{
return true;
}
static inline int task_in_mem_cgroup(struct task_struct *task,
const struct mem_cgroup *memcg)
{
return 1;
}
static inline struct cgroup_subsys_state
*mem_cgroup_css(struct mem_cgroup *memcg)
{
return NULL;
}
static inline void
mem_cgroup_prepare_migration(struct page *page, struct page *newpage,
struct mem_cgroup **memcgp)
{
}
static inline void mem_cgroup_end_migration(struct mem_cgroup *memcg,
struct page *oldpage, struct page *newpage, bool migration_ok)
{
}
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 bool mem_cgroup_disabled(void)
{
return true;
}
static inline int
mem_cgroup_inactive_anon_is_low(struct lruvec *lruvec)
{
return 1;
}
static inline int
mem_cgroup_inactive_file_is_low(struct lruvec *lruvec)
{
return 1;
}
static inline unsigned long
mem_cgroup_get_lru_size(struct lruvec *lruvec, enum lru_list lru)
{
return 0;
}
static inline void
mem_cgroup_update_lru_size(struct lruvec *lruvec, enum lru_list lru,
int increment)
{
}
static inline void
mem_cgroup_print_oom_info(struct mem_cgroup *memcg, struct task_struct *p)
{
}
static inline void mem_cgroup_begin_update_page_stat(struct page *page,
bool *locked, unsigned long *flags)
{
}
static inline void mem_cgroup_end_update_page_stat(struct page *page,
bool *locked, unsigned long *flags)
{
}
static inline void mem_cgroup_inc_page_stat(struct page *page,
enum mem_cgroup_page_stat_item idx)
{
}
static inline void mem_cgroup_dec_page_stat(struct page *page,
enum mem_cgroup_page_stat_item idx)
{
}
static inline
unsigned long mem_cgroup_soft_limit_reclaim(struct zone *zone, 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)
{
}
static inline void mem_cgroup_replace_page_cache(struct page *oldpage,
struct page *newpage)
{
}
#endif /* CONFIG_MEMCG */
#if !defined(CONFIG_MEMCG) || !defined(CONFIG_DEBUG_VM)
static inline bool
mem_cgroup_bad_page_check(struct page *page)
{
return false;
}
static inline void
mem_cgroup_print_bad_page(struct page *page)
{
}
#endif
enum {
UNDER_LIMIT,
SOFT_LIMIT,
OVER_LIMIT,
};
struct sock;
#if defined(CONFIG_INET) && defined(CONFIG_MEMCG_KMEM)
void sock_update_memcg(struct sock *sk);
void sock_release_memcg(struct sock *sk);
#else
static inline void sock_update_memcg(struct sock *sk)
{
}
static inline void sock_release_memcg(struct sock *sk)
{
}
#endif /* CONFIG_INET && CONFIG_MEMCG_KMEM */
#ifdef CONFIG_MEMCG_KMEM
extern struct static_key memcg_kmem_enabled_key;
extern int memcg_limited_groups_array_size;
/*
* 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_limited_groups_array_size; (_idx)++)
static inline bool memcg_kmem_enabled(void)
{
return static_key_false(&memcg_kmem_enabled_key);
}
/*
* In general, we'll do everything in our power to not incur in any overhead
* for non-memcg users for the kmem functions. Not even a function call, if we
* can avoid it.
*
* Therefore, we'll inline all those functions so that in the best case, we'll
* see that kmemcg is off for everybody and proceed quickly. If it is on,
* we'll still do most of the flag checking inline. We check a lot of
* conditions, but because they are pretty simple, they are expected to be
* fast.
*/
bool __memcg_kmem_newpage_charge(gfp_t gfp, struct mem_cgroup **memcg,
int order);
void __memcg_kmem_commit_charge(struct page *page,
struct mem_cgroup *memcg, int order);
void __memcg_kmem_uncharge_pages(struct page *page, int order);
int memcg_cache_id(struct mem_cgroup *memcg);
int memcg_register_cache(struct mem_cgroup *memcg, struct kmem_cache *s,
struct kmem_cache *root_cache);
void memcg_release_cache(struct kmem_cache *cachep);
void memcg_cache_list_add(struct mem_cgroup *memcg, struct kmem_cache *cachep);
int memcg_update_cache_size(struct kmem_cache *s, int num_groups);
void memcg_update_array_size(int num_groups);
struct kmem_cache *
__memcg_kmem_get_cache(struct kmem_cache *cachep, gfp_t gfp);
void mem_cgroup_destroy_cache(struct kmem_cache *cachep);
void kmem_cache_destroy_memcg_children(struct kmem_cache *s);
/**
* memcg_kmem_newpage_charge: verify if a new kmem allocation is allowed.
* @gfp: the gfp allocation flags.
* @memcg: a pointer to the memcg this was charged against.
* @order: allocation order.
*
* returns true if the memcg where the current task belongs can hold this
* allocation.
*
* We return true automatically if this allocation is not to be accounted to
* any memcg.
*/
static inline bool
memcg_kmem_newpage_charge(gfp_t gfp, struct mem_cgroup **memcg, int order)
{
if (!memcg_kmem_enabled())
return true;
/*
* __GFP_NOFAIL allocations will move on even if charging is not
* possible. Therefore we don't even try, and have this allocation
* unaccounted. We could in theory charge it with
* res_counter_charge_nofail, but we hope those allocations are rare,
* and won't be worth the trouble.
*/
if (!(gfp & __GFP_KMEMCG) || (gfp & __GFP_NOFAIL))
return true;
if (in_interrupt() || (!current->mm) || (current->flags & PF_KTHREAD))
return true;
/* If the test is dying, just let it go. */
if (unlikely(fatal_signal_pending(current)))
return true;
return __memcg_kmem_newpage_charge(gfp, memcg, order);
}
/**
* memcg_kmem_uncharge_pages: uncharge pages from memcg
* @page: pointer to struct page being freed
* @order: allocation order.
*
* there is no need to specify memcg here, since it is embedded in page_cgroup
*/
static inline void
memcg_kmem_uncharge_pages(struct page *page, int order)
{
if (memcg_kmem_enabled())
__memcg_kmem_uncharge_pages(page, order);
}
/**
* memcg_kmem_commit_charge: embeds correct memcg in a page
* @page: pointer to struct page recently allocated
* @memcg: the memcg structure we charged against
* @order: allocation order.
*
* Needs to be called after memcg_kmem_newpage_charge, regardless of success or
* failure of the allocation. if @page is NULL, this function will revert the
* charges. Otherwise, it will commit the memcg given by @memcg to the
* corresponding page_cgroup.
*/
static inline void
memcg_kmem_commit_charge(struct page *page, struct mem_cgroup *memcg, int order)
{
if (memcg_kmem_enabled() && memcg)
__memcg_kmem_commit_charge(page, memcg, order);
}
/**
* memcg_kmem_get_cache: selects the correct per-memcg cache for allocation
* @cachep: the original global kmem cache
* @gfp: allocation flags.
*
* This function assumes that the task allocating, which determines the memcg
* in the page allocator, belongs to the same cgroup throughout the whole
* process. Misacounting can happen if the task calls memcg_kmem_get_cache()
* while belonging to a cgroup, and later on changes. This is considered
* acceptable, and should only happen upon task migration.
*
* Before the cache is created by the memcg core, there is also a possible
* imbalance: the task belongs to a memcg, but the cache being allocated from
* is the global cache, since the child cache is not yet guaranteed to be
* ready. This case is also fine, since in this case the GFP_KMEMCG will not be
* passed and the page allocator will not attempt any cgroup accounting.
*/
static __always_inline struct kmem_cache *
memcg_kmem_get_cache(struct kmem_cache *cachep, gfp_t gfp)
{
if (!memcg_kmem_enabled())
return cachep;
if (gfp & __GFP_NOFAIL)
return cachep;
if (in_interrupt() || (!current->mm) || (current->flags & PF_KTHREAD))
return cachep;
if (unlikely(fatal_signal_pending(current)))
return cachep;
return __memcg_kmem_get_cache(cachep, gfp);
}
#else
#define for_each_memcg_cache_index(_idx) \
for (; NULL; )
static inline bool memcg_kmem_enabled(void)
{
return false;
}
static inline bool
memcg_kmem_newpage_charge(gfp_t gfp, struct mem_cgroup **memcg, int order)
{
return true;
}
static inline void memcg_kmem_uncharge_pages(struct page *page, int order)
{
}
static inline void
memcg_kmem_commit_charge(struct page *page, struct mem_cgroup *memcg, int order)
{
}
static inline int memcg_cache_id(struct mem_cgroup *memcg)
{
return -1;
}
static inline int
memcg_register_cache(struct mem_cgroup *memcg, struct kmem_cache *s,
struct kmem_cache *root_cache)
{
return 0;
}
static inline void memcg_release_cache(struct kmem_cache *cachep)
{
}
static inline void memcg_cache_list_add(struct mem_cgroup *memcg,
struct kmem_cache *s)
{
}
static inline struct kmem_cache *
memcg_kmem_get_cache(struct kmem_cache *cachep, gfp_t gfp)
{
return cachep;
}
static inline void kmem_cache_destroy_memcg_children(struct kmem_cache *s)
{
}
#endif /* CONFIG_MEMCG_KMEM */
#endif /* _LINUX_MEMCONTROL_H */