mirror of https://gitee.com/openkylin/linux.git
7284 lines
188 KiB
C
7284 lines
188 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
/* memcontrol.c - 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>
|
|
*
|
|
* Memory thresholds
|
|
* Copyright (C) 2009 Nokia Corporation
|
|
* Author: Kirill A. Shutemov
|
|
*
|
|
* Kernel Memory Controller
|
|
* Copyright (C) 2012 Parallels Inc. and Google Inc.
|
|
* Authors: Glauber Costa and Suleiman Souhlal
|
|
*
|
|
* Native page reclaim
|
|
* Charge lifetime sanitation
|
|
* Lockless page tracking & accounting
|
|
* Unified hierarchy configuration model
|
|
* Copyright (C) 2015 Red Hat, Inc., Johannes Weiner
|
|
*/
|
|
|
|
#include <linux/page_counter.h>
|
|
#include <linux/memcontrol.h>
|
|
#include <linux/cgroup.h>
|
|
#include <linux/pagewalk.h>
|
|
#include <linux/sched/mm.h>
|
|
#include <linux/shmem_fs.h>
|
|
#include <linux/hugetlb.h>
|
|
#include <linux/pagemap.h>
|
|
#include <linux/vm_event_item.h>
|
|
#include <linux/smp.h>
|
|
#include <linux/page-flags.h>
|
|
#include <linux/backing-dev.h>
|
|
#include <linux/bit_spinlock.h>
|
|
#include <linux/rcupdate.h>
|
|
#include <linux/limits.h>
|
|
#include <linux/export.h>
|
|
#include <linux/mutex.h>
|
|
#include <linux/rbtree.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/swap.h>
|
|
#include <linux/swapops.h>
|
|
#include <linux/spinlock.h>
|
|
#include <linux/eventfd.h>
|
|
#include <linux/poll.h>
|
|
#include <linux/sort.h>
|
|
#include <linux/fs.h>
|
|
#include <linux/seq_file.h>
|
|
#include <linux/vmpressure.h>
|
|
#include <linux/mm_inline.h>
|
|
#include <linux/swap_cgroup.h>
|
|
#include <linux/cpu.h>
|
|
#include <linux/oom.h>
|
|
#include <linux/lockdep.h>
|
|
#include <linux/file.h>
|
|
#include <linux/tracehook.h>
|
|
#include <linux/psi.h>
|
|
#include <linux/seq_buf.h>
|
|
#include "internal.h"
|
|
#include <net/sock.h>
|
|
#include <net/ip.h>
|
|
#include "slab.h"
|
|
|
|
#include <linux/uaccess.h>
|
|
|
|
#include <trace/events/vmscan.h>
|
|
|
|
struct cgroup_subsys memory_cgrp_subsys __read_mostly;
|
|
EXPORT_SYMBOL(memory_cgrp_subsys);
|
|
|
|
struct mem_cgroup *root_mem_cgroup __read_mostly;
|
|
|
|
#define MEM_CGROUP_RECLAIM_RETRIES 5
|
|
|
|
/* Socket memory accounting disabled? */
|
|
static bool cgroup_memory_nosocket;
|
|
|
|
/* Kernel memory accounting disabled? */
|
|
static bool cgroup_memory_nokmem;
|
|
|
|
/* Whether the swap controller is active */
|
|
#ifdef CONFIG_MEMCG_SWAP
|
|
int do_swap_account __read_mostly;
|
|
#else
|
|
#define do_swap_account 0
|
|
#endif
|
|
|
|
#ifdef CONFIG_CGROUP_WRITEBACK
|
|
static DECLARE_WAIT_QUEUE_HEAD(memcg_cgwb_frn_waitq);
|
|
#endif
|
|
|
|
/* Whether legacy memory+swap accounting is active */
|
|
static bool do_memsw_account(void)
|
|
{
|
|
return !cgroup_subsys_on_dfl(memory_cgrp_subsys) && do_swap_account;
|
|
}
|
|
|
|
static const char *const mem_cgroup_lru_names[] = {
|
|
"inactive_anon",
|
|
"active_anon",
|
|
"inactive_file",
|
|
"active_file",
|
|
"unevictable",
|
|
};
|
|
|
|
#define THRESHOLDS_EVENTS_TARGET 128
|
|
#define SOFTLIMIT_EVENTS_TARGET 1024
|
|
#define NUMAINFO_EVENTS_TARGET 1024
|
|
|
|
/*
|
|
* Cgroups above their limits are maintained in a RB-Tree, independent of
|
|
* their hierarchy representation
|
|
*/
|
|
|
|
struct mem_cgroup_tree_per_node {
|
|
struct rb_root rb_root;
|
|
struct rb_node *rb_rightmost;
|
|
spinlock_t lock;
|
|
};
|
|
|
|
struct mem_cgroup_tree {
|
|
struct mem_cgroup_tree_per_node *rb_tree_per_node[MAX_NUMNODES];
|
|
};
|
|
|
|
static struct mem_cgroup_tree soft_limit_tree __read_mostly;
|
|
|
|
/* for OOM */
|
|
struct mem_cgroup_eventfd_list {
|
|
struct list_head list;
|
|
struct eventfd_ctx *eventfd;
|
|
};
|
|
|
|
/*
|
|
* cgroup_event represents events which userspace want to receive.
|
|
*/
|
|
struct mem_cgroup_event {
|
|
/*
|
|
* memcg which the event belongs to.
|
|
*/
|
|
struct mem_cgroup *memcg;
|
|
/*
|
|
* eventfd to signal userspace about the event.
|
|
*/
|
|
struct eventfd_ctx *eventfd;
|
|
/*
|
|
* Each of these stored in a list by the cgroup.
|
|
*/
|
|
struct list_head list;
|
|
/*
|
|
* register_event() callback will be used to add new userspace
|
|
* waiter for changes related to this event. Use eventfd_signal()
|
|
* on eventfd to send notification to userspace.
|
|
*/
|
|
int (*register_event)(struct mem_cgroup *memcg,
|
|
struct eventfd_ctx *eventfd, const char *args);
|
|
/*
|
|
* unregister_event() callback will be called when userspace closes
|
|
* the eventfd or on cgroup removing. This callback must be set,
|
|
* if you want provide notification functionality.
|
|
*/
|
|
void (*unregister_event)(struct mem_cgroup *memcg,
|
|
struct eventfd_ctx *eventfd);
|
|
/*
|
|
* All fields below needed to unregister event when
|
|
* userspace closes eventfd.
|
|
*/
|
|
poll_table pt;
|
|
wait_queue_head_t *wqh;
|
|
wait_queue_entry_t wait;
|
|
struct work_struct remove;
|
|
};
|
|
|
|
static void mem_cgroup_threshold(struct mem_cgroup *memcg);
|
|
static void mem_cgroup_oom_notify(struct mem_cgroup *memcg);
|
|
|
|
/* Stuffs for move charges at task migration. */
|
|
/*
|
|
* Types of charges to be moved.
|
|
*/
|
|
#define MOVE_ANON 0x1U
|
|
#define MOVE_FILE 0x2U
|
|
#define MOVE_MASK (MOVE_ANON | MOVE_FILE)
|
|
|
|
/* "mc" and its members are protected by cgroup_mutex */
|
|
static struct move_charge_struct {
|
|
spinlock_t lock; /* for from, to */
|
|
struct mm_struct *mm;
|
|
struct mem_cgroup *from;
|
|
struct mem_cgroup *to;
|
|
unsigned long flags;
|
|
unsigned long precharge;
|
|
unsigned long moved_charge;
|
|
unsigned long moved_swap;
|
|
struct task_struct *moving_task; /* a task moving charges */
|
|
wait_queue_head_t waitq; /* a waitq for other context */
|
|
} mc = {
|
|
.lock = __SPIN_LOCK_UNLOCKED(mc.lock),
|
|
.waitq = __WAIT_QUEUE_HEAD_INITIALIZER(mc.waitq),
|
|
};
|
|
|
|
/*
|
|
* Maximum loops in mem_cgroup_hierarchical_reclaim(), used for soft
|
|
* limit reclaim to prevent infinite loops, if they ever occur.
|
|
*/
|
|
#define MEM_CGROUP_MAX_RECLAIM_LOOPS 100
|
|
#define MEM_CGROUP_MAX_SOFT_LIMIT_RECLAIM_LOOPS 2
|
|
|
|
enum charge_type {
|
|
MEM_CGROUP_CHARGE_TYPE_CACHE = 0,
|
|
MEM_CGROUP_CHARGE_TYPE_ANON,
|
|
MEM_CGROUP_CHARGE_TYPE_SWAPOUT, /* for accounting swapcache */
|
|
MEM_CGROUP_CHARGE_TYPE_DROP, /* a page was unused swap cache */
|
|
NR_CHARGE_TYPE,
|
|
};
|
|
|
|
/* for encoding cft->private value on file */
|
|
enum res_type {
|
|
_MEM,
|
|
_MEMSWAP,
|
|
_OOM_TYPE,
|
|
_KMEM,
|
|
_TCP,
|
|
};
|
|
|
|
#define MEMFILE_PRIVATE(x, val) ((x) << 16 | (val))
|
|
#define MEMFILE_TYPE(val) ((val) >> 16 & 0xffff)
|
|
#define MEMFILE_ATTR(val) ((val) & 0xffff)
|
|
/* Used for OOM nofiier */
|
|
#define OOM_CONTROL (0)
|
|
|
|
/*
|
|
* Iteration constructs for visiting all cgroups (under a tree). If
|
|
* loops are exited prematurely (break), mem_cgroup_iter_break() must
|
|
* be used for reference counting.
|
|
*/
|
|
#define for_each_mem_cgroup_tree(iter, root) \
|
|
for (iter = mem_cgroup_iter(root, NULL, NULL); \
|
|
iter != NULL; \
|
|
iter = mem_cgroup_iter(root, iter, NULL))
|
|
|
|
#define for_each_mem_cgroup(iter) \
|
|
for (iter = mem_cgroup_iter(NULL, NULL, NULL); \
|
|
iter != NULL; \
|
|
iter = mem_cgroup_iter(NULL, iter, NULL))
|
|
|
|
static inline bool should_force_charge(void)
|
|
{
|
|
return tsk_is_oom_victim(current) || fatal_signal_pending(current) ||
|
|
(current->flags & PF_EXITING);
|
|
}
|
|
|
|
/* Some nice accessors for the vmpressure. */
|
|
struct vmpressure *memcg_to_vmpressure(struct mem_cgroup *memcg)
|
|
{
|
|
if (!memcg)
|
|
memcg = root_mem_cgroup;
|
|
return &memcg->vmpressure;
|
|
}
|
|
|
|
struct cgroup_subsys_state *vmpressure_to_css(struct vmpressure *vmpr)
|
|
{
|
|
return &container_of(vmpr, struct mem_cgroup, vmpressure)->css;
|
|
}
|
|
|
|
#ifdef CONFIG_MEMCG_KMEM
|
|
/*
|
|
* This will be the memcg's index in each cache's ->memcg_params.memcg_caches.
|
|
* The main reason for not using cgroup id for this:
|
|
* this works better in sparse environments, where we have a lot of memcgs,
|
|
* but only a few kmem-limited. Or also, if we have, for instance, 200
|
|
* memcgs, and none but the 200th is kmem-limited, we'd have to have a
|
|
* 200 entry array for that.
|
|
*
|
|
* The current size of the caches array is stored in memcg_nr_cache_ids. It
|
|
* will double each time we have to increase it.
|
|
*/
|
|
static DEFINE_IDA(memcg_cache_ida);
|
|
int memcg_nr_cache_ids;
|
|
|
|
/* Protects memcg_nr_cache_ids */
|
|
static DECLARE_RWSEM(memcg_cache_ids_sem);
|
|
|
|
void memcg_get_cache_ids(void)
|
|
{
|
|
down_read(&memcg_cache_ids_sem);
|
|
}
|
|
|
|
void memcg_put_cache_ids(void)
|
|
{
|
|
up_read(&memcg_cache_ids_sem);
|
|
}
|
|
|
|
/*
|
|
* MIN_SIZE is different than 1, because we would like to avoid going through
|
|
* the alloc/free process all the time. In a small machine, 4 kmem-limited
|
|
* cgroups is a reasonable guess. In the future, it could be a parameter or
|
|
* tunable, but that is strictly not necessary.
|
|
*
|
|
* MAX_SIZE should be as large as the number of cgrp_ids. Ideally, we could get
|
|
* this constant directly from cgroup, but it is understandable that this is
|
|
* better kept as an internal representation in cgroup.c. In any case, the
|
|
* cgrp_id space is not getting any smaller, and we don't have to necessarily
|
|
* increase ours as well if it increases.
|
|
*/
|
|
#define MEMCG_CACHES_MIN_SIZE 4
|
|
#define MEMCG_CACHES_MAX_SIZE MEM_CGROUP_ID_MAX
|
|
|
|
/*
|
|
* A lot of the calls to the cache allocation functions are expected to be
|
|
* inlined by the compiler. Since the calls to memcg_kmem_get_cache are
|
|
* conditional to this static branch, we'll have to allow modules that does
|
|
* kmem_cache_alloc and the such to see this symbol as well
|
|
*/
|
|
DEFINE_STATIC_KEY_FALSE(memcg_kmem_enabled_key);
|
|
EXPORT_SYMBOL(memcg_kmem_enabled_key);
|
|
|
|
struct workqueue_struct *memcg_kmem_cache_wq;
|
|
#endif
|
|
|
|
static int memcg_shrinker_map_size;
|
|
static DEFINE_MUTEX(memcg_shrinker_map_mutex);
|
|
|
|
static void memcg_free_shrinker_map_rcu(struct rcu_head *head)
|
|
{
|
|
kvfree(container_of(head, struct memcg_shrinker_map, rcu));
|
|
}
|
|
|
|
static int memcg_expand_one_shrinker_map(struct mem_cgroup *memcg,
|
|
int size, int old_size)
|
|
{
|
|
struct memcg_shrinker_map *new, *old;
|
|
int nid;
|
|
|
|
lockdep_assert_held(&memcg_shrinker_map_mutex);
|
|
|
|
for_each_node(nid) {
|
|
old = rcu_dereference_protected(
|
|
mem_cgroup_nodeinfo(memcg, nid)->shrinker_map, true);
|
|
/* Not yet online memcg */
|
|
if (!old)
|
|
return 0;
|
|
|
|
new = kvmalloc(sizeof(*new) + size, GFP_KERNEL);
|
|
if (!new)
|
|
return -ENOMEM;
|
|
|
|
/* Set all old bits, clear all new bits */
|
|
memset(new->map, (int)0xff, old_size);
|
|
memset((void *)new->map + old_size, 0, size - old_size);
|
|
|
|
rcu_assign_pointer(memcg->nodeinfo[nid]->shrinker_map, new);
|
|
call_rcu(&old->rcu, memcg_free_shrinker_map_rcu);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void memcg_free_shrinker_maps(struct mem_cgroup *memcg)
|
|
{
|
|
struct mem_cgroup_per_node *pn;
|
|
struct memcg_shrinker_map *map;
|
|
int nid;
|
|
|
|
if (mem_cgroup_is_root(memcg))
|
|
return;
|
|
|
|
for_each_node(nid) {
|
|
pn = mem_cgroup_nodeinfo(memcg, nid);
|
|
map = rcu_dereference_protected(pn->shrinker_map, true);
|
|
if (map)
|
|
kvfree(map);
|
|
rcu_assign_pointer(pn->shrinker_map, NULL);
|
|
}
|
|
}
|
|
|
|
static int memcg_alloc_shrinker_maps(struct mem_cgroup *memcg)
|
|
{
|
|
struct memcg_shrinker_map *map;
|
|
int nid, size, ret = 0;
|
|
|
|
if (mem_cgroup_is_root(memcg))
|
|
return 0;
|
|
|
|
mutex_lock(&memcg_shrinker_map_mutex);
|
|
size = memcg_shrinker_map_size;
|
|
for_each_node(nid) {
|
|
map = kvzalloc(sizeof(*map) + size, GFP_KERNEL);
|
|
if (!map) {
|
|
memcg_free_shrinker_maps(memcg);
|
|
ret = -ENOMEM;
|
|
break;
|
|
}
|
|
rcu_assign_pointer(memcg->nodeinfo[nid]->shrinker_map, map);
|
|
}
|
|
mutex_unlock(&memcg_shrinker_map_mutex);
|
|
|
|
return ret;
|
|
}
|
|
|
|
int memcg_expand_shrinker_maps(int new_id)
|
|
{
|
|
int size, old_size, ret = 0;
|
|
struct mem_cgroup *memcg;
|
|
|
|
size = DIV_ROUND_UP(new_id + 1, BITS_PER_LONG) * sizeof(unsigned long);
|
|
old_size = memcg_shrinker_map_size;
|
|
if (size <= old_size)
|
|
return 0;
|
|
|
|
mutex_lock(&memcg_shrinker_map_mutex);
|
|
if (!root_mem_cgroup)
|
|
goto unlock;
|
|
|
|
for_each_mem_cgroup(memcg) {
|
|
if (mem_cgroup_is_root(memcg))
|
|
continue;
|
|
ret = memcg_expand_one_shrinker_map(memcg, size, old_size);
|
|
if (ret)
|
|
goto unlock;
|
|
}
|
|
unlock:
|
|
if (!ret)
|
|
memcg_shrinker_map_size = size;
|
|
mutex_unlock(&memcg_shrinker_map_mutex);
|
|
return ret;
|
|
}
|
|
|
|
void memcg_set_shrinker_bit(struct mem_cgroup *memcg, int nid, int shrinker_id)
|
|
{
|
|
if (shrinker_id >= 0 && memcg && !mem_cgroup_is_root(memcg)) {
|
|
struct memcg_shrinker_map *map;
|
|
|
|
rcu_read_lock();
|
|
map = rcu_dereference(memcg->nodeinfo[nid]->shrinker_map);
|
|
/* Pairs with smp mb in shrink_slab() */
|
|
smp_mb__before_atomic();
|
|
set_bit(shrinker_id, map->map);
|
|
rcu_read_unlock();
|
|
}
|
|
}
|
|
|
|
/**
|
|
* mem_cgroup_css_from_page - css of the memcg associated with a page
|
|
* @page: page of interest
|
|
*
|
|
* If memcg is bound to the default hierarchy, css of the memcg associated
|
|
* with @page is returned. The returned css remains associated with @page
|
|
* until it is released.
|
|
*
|
|
* If memcg is bound to a traditional hierarchy, the css of root_mem_cgroup
|
|
* is returned.
|
|
*/
|
|
struct cgroup_subsys_state *mem_cgroup_css_from_page(struct page *page)
|
|
{
|
|
struct mem_cgroup *memcg;
|
|
|
|
memcg = page->mem_cgroup;
|
|
|
|
if (!memcg || !cgroup_subsys_on_dfl(memory_cgrp_subsys))
|
|
memcg = root_mem_cgroup;
|
|
|
|
return &memcg->css;
|
|
}
|
|
|
|
/**
|
|
* page_cgroup_ino - return inode number of the memcg a page is charged to
|
|
* @page: the page
|
|
*
|
|
* Look up the closest online ancestor of the memory cgroup @page is charged to
|
|
* and return its inode number or 0 if @page is not charged to any cgroup. It
|
|
* is safe to call this function without holding a reference to @page.
|
|
*
|
|
* Note, this function is inherently racy, because there is nothing to prevent
|
|
* the cgroup inode from getting torn down and potentially reallocated a moment
|
|
* after page_cgroup_ino() returns, so it only should be used by callers that
|
|
* do not care (such as procfs interfaces).
|
|
*/
|
|
ino_t page_cgroup_ino(struct page *page)
|
|
{
|
|
struct mem_cgroup *memcg;
|
|
unsigned long ino = 0;
|
|
|
|
rcu_read_lock();
|
|
if (PageHead(page) && PageSlab(page))
|
|
memcg = memcg_from_slab_page(page);
|
|
else
|
|
memcg = READ_ONCE(page->mem_cgroup);
|
|
while (memcg && !(memcg->css.flags & CSS_ONLINE))
|
|
memcg = parent_mem_cgroup(memcg);
|
|
if (memcg)
|
|
ino = cgroup_ino(memcg->css.cgroup);
|
|
rcu_read_unlock();
|
|
return ino;
|
|
}
|
|
|
|
static struct mem_cgroup_per_node *
|
|
mem_cgroup_page_nodeinfo(struct mem_cgroup *memcg, struct page *page)
|
|
{
|
|
int nid = page_to_nid(page);
|
|
|
|
return memcg->nodeinfo[nid];
|
|
}
|
|
|
|
static struct mem_cgroup_tree_per_node *
|
|
soft_limit_tree_node(int nid)
|
|
{
|
|
return soft_limit_tree.rb_tree_per_node[nid];
|
|
}
|
|
|
|
static struct mem_cgroup_tree_per_node *
|
|
soft_limit_tree_from_page(struct page *page)
|
|
{
|
|
int nid = page_to_nid(page);
|
|
|
|
return soft_limit_tree.rb_tree_per_node[nid];
|
|
}
|
|
|
|
static void __mem_cgroup_insert_exceeded(struct mem_cgroup_per_node *mz,
|
|
struct mem_cgroup_tree_per_node *mctz,
|
|
unsigned long new_usage_in_excess)
|
|
{
|
|
struct rb_node **p = &mctz->rb_root.rb_node;
|
|
struct rb_node *parent = NULL;
|
|
struct mem_cgroup_per_node *mz_node;
|
|
bool rightmost = true;
|
|
|
|
if (mz->on_tree)
|
|
return;
|
|
|
|
mz->usage_in_excess = new_usage_in_excess;
|
|
if (!mz->usage_in_excess)
|
|
return;
|
|
while (*p) {
|
|
parent = *p;
|
|
mz_node = rb_entry(parent, struct mem_cgroup_per_node,
|
|
tree_node);
|
|
if (mz->usage_in_excess < mz_node->usage_in_excess) {
|
|
p = &(*p)->rb_left;
|
|
rightmost = false;
|
|
}
|
|
|
|
/*
|
|
* We can't avoid mem cgroups that are over their soft
|
|
* limit by the same amount
|
|
*/
|
|
else if (mz->usage_in_excess >= mz_node->usage_in_excess)
|
|
p = &(*p)->rb_right;
|
|
}
|
|
|
|
if (rightmost)
|
|
mctz->rb_rightmost = &mz->tree_node;
|
|
|
|
rb_link_node(&mz->tree_node, parent, p);
|
|
rb_insert_color(&mz->tree_node, &mctz->rb_root);
|
|
mz->on_tree = true;
|
|
}
|
|
|
|
static void __mem_cgroup_remove_exceeded(struct mem_cgroup_per_node *mz,
|
|
struct mem_cgroup_tree_per_node *mctz)
|
|
{
|
|
if (!mz->on_tree)
|
|
return;
|
|
|
|
if (&mz->tree_node == mctz->rb_rightmost)
|
|
mctz->rb_rightmost = rb_prev(&mz->tree_node);
|
|
|
|
rb_erase(&mz->tree_node, &mctz->rb_root);
|
|
mz->on_tree = false;
|
|
}
|
|
|
|
static void mem_cgroup_remove_exceeded(struct mem_cgroup_per_node *mz,
|
|
struct mem_cgroup_tree_per_node *mctz)
|
|
{
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&mctz->lock, flags);
|
|
__mem_cgroup_remove_exceeded(mz, mctz);
|
|
spin_unlock_irqrestore(&mctz->lock, flags);
|
|
}
|
|
|
|
static unsigned long soft_limit_excess(struct mem_cgroup *memcg)
|
|
{
|
|
unsigned long nr_pages = page_counter_read(&memcg->memory);
|
|
unsigned long soft_limit = READ_ONCE(memcg->soft_limit);
|
|
unsigned long excess = 0;
|
|
|
|
if (nr_pages > soft_limit)
|
|
excess = nr_pages - soft_limit;
|
|
|
|
return excess;
|
|
}
|
|
|
|
static void mem_cgroup_update_tree(struct mem_cgroup *memcg, struct page *page)
|
|
{
|
|
unsigned long excess;
|
|
struct mem_cgroup_per_node *mz;
|
|
struct mem_cgroup_tree_per_node *mctz;
|
|
|
|
mctz = soft_limit_tree_from_page(page);
|
|
if (!mctz)
|
|
return;
|
|
/*
|
|
* Necessary to update all ancestors when hierarchy is used.
|
|
* because their event counter is not touched.
|
|
*/
|
|
for (; memcg; memcg = parent_mem_cgroup(memcg)) {
|
|
mz = mem_cgroup_page_nodeinfo(memcg, page);
|
|
excess = soft_limit_excess(memcg);
|
|
/*
|
|
* We have to update the tree if mz is on RB-tree or
|
|
* mem is over its softlimit.
|
|
*/
|
|
if (excess || mz->on_tree) {
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&mctz->lock, flags);
|
|
/* if on-tree, remove it */
|
|
if (mz->on_tree)
|
|
__mem_cgroup_remove_exceeded(mz, mctz);
|
|
/*
|
|
* Insert again. mz->usage_in_excess will be updated.
|
|
* If excess is 0, no tree ops.
|
|
*/
|
|
__mem_cgroup_insert_exceeded(mz, mctz, excess);
|
|
spin_unlock_irqrestore(&mctz->lock, flags);
|
|
}
|
|
}
|
|
}
|
|
|
|
static void mem_cgroup_remove_from_trees(struct mem_cgroup *memcg)
|
|
{
|
|
struct mem_cgroup_tree_per_node *mctz;
|
|
struct mem_cgroup_per_node *mz;
|
|
int nid;
|
|
|
|
for_each_node(nid) {
|
|
mz = mem_cgroup_nodeinfo(memcg, nid);
|
|
mctz = soft_limit_tree_node(nid);
|
|
if (mctz)
|
|
mem_cgroup_remove_exceeded(mz, mctz);
|
|
}
|
|
}
|
|
|
|
static struct mem_cgroup_per_node *
|
|
__mem_cgroup_largest_soft_limit_node(struct mem_cgroup_tree_per_node *mctz)
|
|
{
|
|
struct mem_cgroup_per_node *mz;
|
|
|
|
retry:
|
|
mz = NULL;
|
|
if (!mctz->rb_rightmost)
|
|
goto done; /* Nothing to reclaim from */
|
|
|
|
mz = rb_entry(mctz->rb_rightmost,
|
|
struct mem_cgroup_per_node, tree_node);
|
|
/*
|
|
* Remove the node now but someone else can add it back,
|
|
* we will to add it back at the end of reclaim to its correct
|
|
* position in the tree.
|
|
*/
|
|
__mem_cgroup_remove_exceeded(mz, mctz);
|
|
if (!soft_limit_excess(mz->memcg) ||
|
|
!css_tryget_online(&mz->memcg->css))
|
|
goto retry;
|
|
done:
|
|
return mz;
|
|
}
|
|
|
|
static struct mem_cgroup_per_node *
|
|
mem_cgroup_largest_soft_limit_node(struct mem_cgroup_tree_per_node *mctz)
|
|
{
|
|
struct mem_cgroup_per_node *mz;
|
|
|
|
spin_lock_irq(&mctz->lock);
|
|
mz = __mem_cgroup_largest_soft_limit_node(mctz);
|
|
spin_unlock_irq(&mctz->lock);
|
|
return mz;
|
|
}
|
|
|
|
/**
|
|
* __mod_memcg_state - update cgroup memory statistics
|
|
* @memcg: the memory cgroup
|
|
* @idx: the stat item - can be enum memcg_stat_item or enum node_stat_item
|
|
* @val: delta to add to the counter, can be negative
|
|
*/
|
|
void __mod_memcg_state(struct mem_cgroup *memcg, int idx, int val)
|
|
{
|
|
long x;
|
|
|
|
if (mem_cgroup_disabled())
|
|
return;
|
|
|
|
x = val + __this_cpu_read(memcg->vmstats_percpu->stat[idx]);
|
|
if (unlikely(abs(x) > MEMCG_CHARGE_BATCH)) {
|
|
struct mem_cgroup *mi;
|
|
|
|
/*
|
|
* Batch local counters to keep them in sync with
|
|
* the hierarchical ones.
|
|
*/
|
|
__this_cpu_add(memcg->vmstats_local->stat[idx], x);
|
|
for (mi = memcg; mi; mi = parent_mem_cgroup(mi))
|
|
atomic_long_add(x, &mi->vmstats[idx]);
|
|
x = 0;
|
|
}
|
|
__this_cpu_write(memcg->vmstats_percpu->stat[idx], x);
|
|
}
|
|
|
|
static struct mem_cgroup_per_node *
|
|
parent_nodeinfo(struct mem_cgroup_per_node *pn, int nid)
|
|
{
|
|
struct mem_cgroup *parent;
|
|
|
|
parent = parent_mem_cgroup(pn->memcg);
|
|
if (!parent)
|
|
return NULL;
|
|
return mem_cgroup_nodeinfo(parent, nid);
|
|
}
|
|
|
|
/**
|
|
* __mod_lruvec_state - update lruvec memory statistics
|
|
* @lruvec: the lruvec
|
|
* @idx: the stat item
|
|
* @val: delta to add to the counter, can be negative
|
|
*
|
|
* The lruvec is the intersection of the NUMA node and a cgroup. This
|
|
* function updates the all three counters that are affected by a
|
|
* change of state at this level: per-node, per-cgroup, per-lruvec.
|
|
*/
|
|
void __mod_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx,
|
|
int val)
|
|
{
|
|
pg_data_t *pgdat = lruvec_pgdat(lruvec);
|
|
struct mem_cgroup_per_node *pn;
|
|
struct mem_cgroup *memcg;
|
|
long x;
|
|
|
|
/* Update node */
|
|
__mod_node_page_state(pgdat, idx, val);
|
|
|
|
if (mem_cgroup_disabled())
|
|
return;
|
|
|
|
pn = container_of(lruvec, struct mem_cgroup_per_node, lruvec);
|
|
memcg = pn->memcg;
|
|
|
|
/* Update memcg */
|
|
__mod_memcg_state(memcg, idx, val);
|
|
|
|
/* Update lruvec */
|
|
__this_cpu_add(pn->lruvec_stat_local->count[idx], val);
|
|
|
|
x = val + __this_cpu_read(pn->lruvec_stat_cpu->count[idx]);
|
|
if (unlikely(abs(x) > MEMCG_CHARGE_BATCH)) {
|
|
struct mem_cgroup_per_node *pi;
|
|
|
|
for (pi = pn; pi; pi = parent_nodeinfo(pi, pgdat->node_id))
|
|
atomic_long_add(x, &pi->lruvec_stat[idx]);
|
|
x = 0;
|
|
}
|
|
__this_cpu_write(pn->lruvec_stat_cpu->count[idx], x);
|
|
}
|
|
|
|
void __mod_lruvec_slab_state(void *p, enum node_stat_item idx, int val)
|
|
{
|
|
struct page *page = virt_to_head_page(p);
|
|
pg_data_t *pgdat = page_pgdat(page);
|
|
struct mem_cgroup *memcg;
|
|
struct lruvec *lruvec;
|
|
|
|
rcu_read_lock();
|
|
memcg = memcg_from_slab_page(page);
|
|
|
|
/* Untracked pages have no memcg, no lruvec. Update only the node */
|
|
if (!memcg || memcg == root_mem_cgroup) {
|
|
__mod_node_page_state(pgdat, idx, val);
|
|
} else {
|
|
lruvec = mem_cgroup_lruvec(pgdat, memcg);
|
|
__mod_lruvec_state(lruvec, idx, val);
|
|
}
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
/**
|
|
* __count_memcg_events - account VM events in a cgroup
|
|
* @memcg: the memory cgroup
|
|
* @idx: the event item
|
|
* @count: the number of events that occured
|
|
*/
|
|
void __count_memcg_events(struct mem_cgroup *memcg, enum vm_event_item idx,
|
|
unsigned long count)
|
|
{
|
|
unsigned long x;
|
|
|
|
if (mem_cgroup_disabled())
|
|
return;
|
|
|
|
x = count + __this_cpu_read(memcg->vmstats_percpu->events[idx]);
|
|
if (unlikely(x > MEMCG_CHARGE_BATCH)) {
|
|
struct mem_cgroup *mi;
|
|
|
|
/*
|
|
* Batch local counters to keep them in sync with
|
|
* the hierarchical ones.
|
|
*/
|
|
__this_cpu_add(memcg->vmstats_local->events[idx], x);
|
|
for (mi = memcg; mi; mi = parent_mem_cgroup(mi))
|
|
atomic_long_add(x, &mi->vmevents[idx]);
|
|
x = 0;
|
|
}
|
|
__this_cpu_write(memcg->vmstats_percpu->events[idx], x);
|
|
}
|
|
|
|
static unsigned long memcg_events(struct mem_cgroup *memcg, int event)
|
|
{
|
|
return atomic_long_read(&memcg->vmevents[event]);
|
|
}
|
|
|
|
static unsigned long memcg_events_local(struct mem_cgroup *memcg, int event)
|
|
{
|
|
long x = 0;
|
|
int cpu;
|
|
|
|
for_each_possible_cpu(cpu)
|
|
x += per_cpu(memcg->vmstats_local->events[event], cpu);
|
|
return x;
|
|
}
|
|
|
|
static void mem_cgroup_charge_statistics(struct mem_cgroup *memcg,
|
|
struct page *page,
|
|
bool compound, int nr_pages)
|
|
{
|
|
/*
|
|
* Here, RSS means 'mapped anon' and anon's SwapCache. Shmem/tmpfs is
|
|
* counted as CACHE even if it's on ANON LRU.
|
|
*/
|
|
if (PageAnon(page))
|
|
__mod_memcg_state(memcg, MEMCG_RSS, nr_pages);
|
|
else {
|
|
__mod_memcg_state(memcg, MEMCG_CACHE, nr_pages);
|
|
if (PageSwapBacked(page))
|
|
__mod_memcg_state(memcg, NR_SHMEM, nr_pages);
|
|
}
|
|
|
|
if (compound) {
|
|
VM_BUG_ON_PAGE(!PageTransHuge(page), page);
|
|
__mod_memcg_state(memcg, MEMCG_RSS_HUGE, nr_pages);
|
|
}
|
|
|
|
/* pagein of a big page is an event. So, ignore page size */
|
|
if (nr_pages > 0)
|
|
__count_memcg_events(memcg, PGPGIN, 1);
|
|
else {
|
|
__count_memcg_events(memcg, PGPGOUT, 1);
|
|
nr_pages = -nr_pages; /* for event */
|
|
}
|
|
|
|
__this_cpu_add(memcg->vmstats_percpu->nr_page_events, nr_pages);
|
|
}
|
|
|
|
static bool mem_cgroup_event_ratelimit(struct mem_cgroup *memcg,
|
|
enum mem_cgroup_events_target target)
|
|
{
|
|
unsigned long val, next;
|
|
|
|
val = __this_cpu_read(memcg->vmstats_percpu->nr_page_events);
|
|
next = __this_cpu_read(memcg->vmstats_percpu->targets[target]);
|
|
/* from time_after() in jiffies.h */
|
|
if ((long)(next - val) < 0) {
|
|
switch (target) {
|
|
case MEM_CGROUP_TARGET_THRESH:
|
|
next = val + THRESHOLDS_EVENTS_TARGET;
|
|
break;
|
|
case MEM_CGROUP_TARGET_SOFTLIMIT:
|
|
next = val + SOFTLIMIT_EVENTS_TARGET;
|
|
break;
|
|
case MEM_CGROUP_TARGET_NUMAINFO:
|
|
next = val + NUMAINFO_EVENTS_TARGET;
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
__this_cpu_write(memcg->vmstats_percpu->targets[target], next);
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
/*
|
|
* Check events in order.
|
|
*
|
|
*/
|
|
static void memcg_check_events(struct mem_cgroup *memcg, struct page *page)
|
|
{
|
|
/* threshold event is triggered in finer grain than soft limit */
|
|
if (unlikely(mem_cgroup_event_ratelimit(memcg,
|
|
MEM_CGROUP_TARGET_THRESH))) {
|
|
bool do_softlimit;
|
|
bool do_numainfo __maybe_unused;
|
|
|
|
do_softlimit = mem_cgroup_event_ratelimit(memcg,
|
|
MEM_CGROUP_TARGET_SOFTLIMIT);
|
|
#if MAX_NUMNODES > 1
|
|
do_numainfo = mem_cgroup_event_ratelimit(memcg,
|
|
MEM_CGROUP_TARGET_NUMAINFO);
|
|
#endif
|
|
mem_cgroup_threshold(memcg);
|
|
if (unlikely(do_softlimit))
|
|
mem_cgroup_update_tree(memcg, page);
|
|
#if MAX_NUMNODES > 1
|
|
if (unlikely(do_numainfo))
|
|
atomic_inc(&memcg->numainfo_events);
|
|
#endif
|
|
}
|
|
}
|
|
|
|
struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p)
|
|
{
|
|
/*
|
|
* mm_update_next_owner() may clear mm->owner to NULL
|
|
* if it races with swapoff, page migration, etc.
|
|
* So this can be called with p == NULL.
|
|
*/
|
|
if (unlikely(!p))
|
|
return NULL;
|
|
|
|
return mem_cgroup_from_css(task_css(p, memory_cgrp_id));
|
|
}
|
|
EXPORT_SYMBOL(mem_cgroup_from_task);
|
|
|
|
/**
|
|
* get_mem_cgroup_from_mm: Obtain a reference on given mm_struct's memcg.
|
|
* @mm: mm from which memcg should be extracted. It can be NULL.
|
|
*
|
|
* Obtain a reference on mm->memcg and returns it if successful. Otherwise
|
|
* root_mem_cgroup is returned. However if mem_cgroup is disabled, NULL is
|
|
* returned.
|
|
*/
|
|
struct mem_cgroup *get_mem_cgroup_from_mm(struct mm_struct *mm)
|
|
{
|
|
struct mem_cgroup *memcg;
|
|
|
|
if (mem_cgroup_disabled())
|
|
return NULL;
|
|
|
|
rcu_read_lock();
|
|
do {
|
|
/*
|
|
* Page cache insertions can happen withou an
|
|
* actual mm context, e.g. during disk probing
|
|
* on boot, loopback IO, acct() writes etc.
|
|
*/
|
|
if (unlikely(!mm))
|
|
memcg = root_mem_cgroup;
|
|
else {
|
|
memcg = mem_cgroup_from_task(rcu_dereference(mm->owner));
|
|
if (unlikely(!memcg))
|
|
memcg = root_mem_cgroup;
|
|
}
|
|
} while (!css_tryget_online(&memcg->css));
|
|
rcu_read_unlock();
|
|
return memcg;
|
|
}
|
|
EXPORT_SYMBOL(get_mem_cgroup_from_mm);
|
|
|
|
/**
|
|
* get_mem_cgroup_from_page: Obtain a reference on given page's memcg.
|
|
* @page: page from which memcg should be extracted.
|
|
*
|
|
* Obtain a reference on page->memcg and returns it if successful. Otherwise
|
|
* root_mem_cgroup is returned.
|
|
*/
|
|
struct mem_cgroup *get_mem_cgroup_from_page(struct page *page)
|
|
{
|
|
struct mem_cgroup *memcg = page->mem_cgroup;
|
|
|
|
if (mem_cgroup_disabled())
|
|
return NULL;
|
|
|
|
rcu_read_lock();
|
|
if (!memcg || !css_tryget_online(&memcg->css))
|
|
memcg = root_mem_cgroup;
|
|
rcu_read_unlock();
|
|
return memcg;
|
|
}
|
|
EXPORT_SYMBOL(get_mem_cgroup_from_page);
|
|
|
|
/**
|
|
* If current->active_memcg is non-NULL, do not fallback to current->mm->memcg.
|
|
*/
|
|
static __always_inline struct mem_cgroup *get_mem_cgroup_from_current(void)
|
|
{
|
|
if (unlikely(current->active_memcg)) {
|
|
struct mem_cgroup *memcg = root_mem_cgroup;
|
|
|
|
rcu_read_lock();
|
|
if (css_tryget_online(¤t->active_memcg->css))
|
|
memcg = current->active_memcg;
|
|
rcu_read_unlock();
|
|
return memcg;
|
|
}
|
|
return get_mem_cgroup_from_mm(current->mm);
|
|
}
|
|
|
|
/**
|
|
* mem_cgroup_iter - iterate over memory cgroup hierarchy
|
|
* @root: hierarchy root
|
|
* @prev: previously returned memcg, NULL on first invocation
|
|
* @reclaim: cookie for shared reclaim walks, NULL for full walks
|
|
*
|
|
* Returns references to children of the hierarchy below @root, or
|
|
* @root itself, or %NULL after a full round-trip.
|
|
*
|
|
* Caller must pass the return value in @prev on subsequent
|
|
* invocations for reference counting, or use mem_cgroup_iter_break()
|
|
* to cancel a hierarchy walk before the round-trip is complete.
|
|
*
|
|
* Reclaimers can specify a node and a priority level in @reclaim to
|
|
* divide up the memcgs in the hierarchy among all concurrent
|
|
* reclaimers operating on the same node and priority.
|
|
*/
|
|
struct mem_cgroup *mem_cgroup_iter(struct mem_cgroup *root,
|
|
struct mem_cgroup *prev,
|
|
struct mem_cgroup_reclaim_cookie *reclaim)
|
|
{
|
|
struct mem_cgroup_reclaim_iter *uninitialized_var(iter);
|
|
struct cgroup_subsys_state *css = NULL;
|
|
struct mem_cgroup *memcg = NULL;
|
|
struct mem_cgroup *pos = NULL;
|
|
|
|
if (mem_cgroup_disabled())
|
|
return NULL;
|
|
|
|
if (!root)
|
|
root = root_mem_cgroup;
|
|
|
|
if (prev && !reclaim)
|
|
pos = prev;
|
|
|
|
if (!root->use_hierarchy && root != root_mem_cgroup) {
|
|
if (prev)
|
|
goto out;
|
|
return root;
|
|
}
|
|
|
|
rcu_read_lock();
|
|
|
|
if (reclaim) {
|
|
struct mem_cgroup_per_node *mz;
|
|
|
|
mz = mem_cgroup_nodeinfo(root, reclaim->pgdat->node_id);
|
|
iter = &mz->iter[reclaim->priority];
|
|
|
|
if (prev && reclaim->generation != iter->generation)
|
|
goto out_unlock;
|
|
|
|
while (1) {
|
|
pos = READ_ONCE(iter->position);
|
|
if (!pos || css_tryget(&pos->css))
|
|
break;
|
|
/*
|
|
* css reference reached zero, so iter->position will
|
|
* be cleared by ->css_released. However, we should not
|
|
* rely on this happening soon, because ->css_released
|
|
* is called from a work queue, and by busy-waiting we
|
|
* might block it. So we clear iter->position right
|
|
* away.
|
|
*/
|
|
(void)cmpxchg(&iter->position, pos, NULL);
|
|
}
|
|
}
|
|
|
|
if (pos)
|
|
css = &pos->css;
|
|
|
|
for (;;) {
|
|
css = css_next_descendant_pre(css, &root->css);
|
|
if (!css) {
|
|
/*
|
|
* Reclaimers share the hierarchy walk, and a
|
|
* new one might jump in right at the end of
|
|
* the hierarchy - make sure they see at least
|
|
* one group and restart from the beginning.
|
|
*/
|
|
if (!prev)
|
|
continue;
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* Verify the css and acquire a reference. The root
|
|
* is provided by the caller, so we know it's alive
|
|
* and kicking, and don't take an extra reference.
|
|
*/
|
|
memcg = mem_cgroup_from_css(css);
|
|
|
|
if (css == &root->css)
|
|
break;
|
|
|
|
if (css_tryget(css))
|
|
break;
|
|
|
|
memcg = NULL;
|
|
}
|
|
|
|
if (reclaim) {
|
|
/*
|
|
* The position could have already been updated by a competing
|
|
* thread, so check that the value hasn't changed since we read
|
|
* it to avoid reclaiming from the same cgroup twice.
|
|
*/
|
|
(void)cmpxchg(&iter->position, pos, memcg);
|
|
|
|
if (pos)
|
|
css_put(&pos->css);
|
|
|
|
if (!memcg)
|
|
iter->generation++;
|
|
else if (!prev)
|
|
reclaim->generation = iter->generation;
|
|
}
|
|
|
|
out_unlock:
|
|
rcu_read_unlock();
|
|
out:
|
|
if (prev && prev != root)
|
|
css_put(&prev->css);
|
|
|
|
return memcg;
|
|
}
|
|
|
|
/**
|
|
* mem_cgroup_iter_break - abort a hierarchy walk prematurely
|
|
* @root: hierarchy root
|
|
* @prev: last visited hierarchy member as returned by mem_cgroup_iter()
|
|
*/
|
|
void mem_cgroup_iter_break(struct mem_cgroup *root,
|
|
struct mem_cgroup *prev)
|
|
{
|
|
if (!root)
|
|
root = root_mem_cgroup;
|
|
if (prev && prev != root)
|
|
css_put(&prev->css);
|
|
}
|
|
|
|
static void __invalidate_reclaim_iterators(struct mem_cgroup *from,
|
|
struct mem_cgroup *dead_memcg)
|
|
{
|
|
struct mem_cgroup_reclaim_iter *iter;
|
|
struct mem_cgroup_per_node *mz;
|
|
int nid;
|
|
int i;
|
|
|
|
for_each_node(nid) {
|
|
mz = mem_cgroup_nodeinfo(from, nid);
|
|
for (i = 0; i <= DEF_PRIORITY; i++) {
|
|
iter = &mz->iter[i];
|
|
cmpxchg(&iter->position,
|
|
dead_memcg, NULL);
|
|
}
|
|
}
|
|
}
|
|
|
|
static void invalidate_reclaim_iterators(struct mem_cgroup *dead_memcg)
|
|
{
|
|
struct mem_cgroup *memcg = dead_memcg;
|
|
struct mem_cgroup *last;
|
|
|
|
do {
|
|
__invalidate_reclaim_iterators(memcg, dead_memcg);
|
|
last = memcg;
|
|
} while ((memcg = parent_mem_cgroup(memcg)));
|
|
|
|
/*
|
|
* When cgruop1 non-hierarchy mode is used,
|
|
* parent_mem_cgroup() does not walk all the way up to the
|
|
* cgroup root (root_mem_cgroup). So we have to handle
|
|
* dead_memcg from cgroup root separately.
|
|
*/
|
|
if (last != root_mem_cgroup)
|
|
__invalidate_reclaim_iterators(root_mem_cgroup,
|
|
dead_memcg);
|
|
}
|
|
|
|
/**
|
|
* mem_cgroup_scan_tasks - iterate over tasks of a memory cgroup hierarchy
|
|
* @memcg: hierarchy root
|
|
* @fn: function to call for each task
|
|
* @arg: argument passed to @fn
|
|
*
|
|
* This function iterates over tasks attached to @memcg or to any of its
|
|
* descendants and calls @fn for each task. If @fn returns a non-zero
|
|
* value, the function breaks the iteration loop and returns the value.
|
|
* Otherwise, it will iterate over all tasks and return 0.
|
|
*
|
|
* This function must not be called for the root memory cgroup.
|
|
*/
|
|
int mem_cgroup_scan_tasks(struct mem_cgroup *memcg,
|
|
int (*fn)(struct task_struct *, void *), void *arg)
|
|
{
|
|
struct mem_cgroup *iter;
|
|
int ret = 0;
|
|
|
|
BUG_ON(memcg == root_mem_cgroup);
|
|
|
|
for_each_mem_cgroup_tree(iter, memcg) {
|
|
struct css_task_iter it;
|
|
struct task_struct *task;
|
|
|
|
css_task_iter_start(&iter->css, CSS_TASK_ITER_PROCS, &it);
|
|
while (!ret && (task = css_task_iter_next(&it)))
|
|
ret = fn(task, arg);
|
|
css_task_iter_end(&it);
|
|
if (ret) {
|
|
mem_cgroup_iter_break(memcg, iter);
|
|
break;
|
|
}
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* mem_cgroup_page_lruvec - return lruvec for isolating/putting an LRU page
|
|
* @page: the page
|
|
* @pgdat: pgdat of the page
|
|
*
|
|
* This function is only safe when following the LRU page isolation
|
|
* and putback protocol: the LRU lock must be held, and the page must
|
|
* either be PageLRU() or the caller must have isolated/allocated it.
|
|
*/
|
|
struct lruvec *mem_cgroup_page_lruvec(struct page *page, struct pglist_data *pgdat)
|
|
{
|
|
struct mem_cgroup_per_node *mz;
|
|
struct mem_cgroup *memcg;
|
|
struct lruvec *lruvec;
|
|
|
|
if (mem_cgroup_disabled()) {
|
|
lruvec = &pgdat->lruvec;
|
|
goto out;
|
|
}
|
|
|
|
memcg = page->mem_cgroup;
|
|
/*
|
|
* Swapcache readahead pages are added to the LRU - and
|
|
* possibly migrated - before they are charged.
|
|
*/
|
|
if (!memcg)
|
|
memcg = root_mem_cgroup;
|
|
|
|
mz = mem_cgroup_page_nodeinfo(memcg, page);
|
|
lruvec = &mz->lruvec;
|
|
out:
|
|
/*
|
|
* Since a node can be onlined after the mem_cgroup was created,
|
|
* we have to be prepared to initialize lruvec->zone here;
|
|
* and if offlined then reonlined, we need to reinitialize it.
|
|
*/
|
|
if (unlikely(lruvec->pgdat != pgdat))
|
|
lruvec->pgdat = pgdat;
|
|
return lruvec;
|
|
}
|
|
|
|
/**
|
|
* mem_cgroup_update_lru_size - account for adding or removing an lru page
|
|
* @lruvec: mem_cgroup per zone lru vector
|
|
* @lru: index of lru list the page is sitting on
|
|
* @zid: zone id of the accounted pages
|
|
* @nr_pages: positive when adding or negative when removing
|
|
*
|
|
* This function must be called under lru_lock, just before a page is added
|
|
* to or just after a page is removed from an lru list (that ordering being
|
|
* so as to allow it to check that lru_size 0 is consistent with list_empty).
|
|
*/
|
|
void mem_cgroup_update_lru_size(struct lruvec *lruvec, enum lru_list lru,
|
|
int zid, int nr_pages)
|
|
{
|
|
struct mem_cgroup_per_node *mz;
|
|
unsigned long *lru_size;
|
|
long size;
|
|
|
|
if (mem_cgroup_disabled())
|
|
return;
|
|
|
|
mz = container_of(lruvec, struct mem_cgroup_per_node, lruvec);
|
|
lru_size = &mz->lru_zone_size[zid][lru];
|
|
|
|
if (nr_pages < 0)
|
|
*lru_size += nr_pages;
|
|
|
|
size = *lru_size;
|
|
if (WARN_ONCE(size < 0,
|
|
"%s(%p, %d, %d): lru_size %ld\n",
|
|
__func__, lruvec, lru, nr_pages, size)) {
|
|
VM_BUG_ON(1);
|
|
*lru_size = 0;
|
|
}
|
|
|
|
if (nr_pages > 0)
|
|
*lru_size += nr_pages;
|
|
}
|
|
|
|
/**
|
|
* mem_cgroup_margin - calculate chargeable space of a memory cgroup
|
|
* @memcg: the memory cgroup
|
|
*
|
|
* Returns the maximum amount of memory @mem can be charged with, in
|
|
* pages.
|
|
*/
|
|
static unsigned long mem_cgroup_margin(struct mem_cgroup *memcg)
|
|
{
|
|
unsigned long margin = 0;
|
|
unsigned long count;
|
|
unsigned long limit;
|
|
|
|
count = page_counter_read(&memcg->memory);
|
|
limit = READ_ONCE(memcg->memory.max);
|
|
if (count < limit)
|
|
margin = limit - count;
|
|
|
|
if (do_memsw_account()) {
|
|
count = page_counter_read(&memcg->memsw);
|
|
limit = READ_ONCE(memcg->memsw.max);
|
|
if (count <= limit)
|
|
margin = min(margin, limit - count);
|
|
else
|
|
margin = 0;
|
|
}
|
|
|
|
return margin;
|
|
}
|
|
|
|
/*
|
|
* A routine for checking "mem" is under move_account() or not.
|
|
*
|
|
* Checking a cgroup is mc.from or mc.to or under hierarchy of
|
|
* moving cgroups. This is for waiting at high-memory pressure
|
|
* caused by "move".
|
|
*/
|
|
static bool mem_cgroup_under_move(struct mem_cgroup *memcg)
|
|
{
|
|
struct mem_cgroup *from;
|
|
struct mem_cgroup *to;
|
|
bool ret = false;
|
|
/*
|
|
* Unlike task_move routines, we access mc.to, mc.from not under
|
|
* mutual exclusion by cgroup_mutex. Here, we take spinlock instead.
|
|
*/
|
|
spin_lock(&mc.lock);
|
|
from = mc.from;
|
|
to = mc.to;
|
|
if (!from)
|
|
goto unlock;
|
|
|
|
ret = mem_cgroup_is_descendant(from, memcg) ||
|
|
mem_cgroup_is_descendant(to, memcg);
|
|
unlock:
|
|
spin_unlock(&mc.lock);
|
|
return ret;
|
|
}
|
|
|
|
static bool mem_cgroup_wait_acct_move(struct mem_cgroup *memcg)
|
|
{
|
|
if (mc.moving_task && current != mc.moving_task) {
|
|
if (mem_cgroup_under_move(memcg)) {
|
|
DEFINE_WAIT(wait);
|
|
prepare_to_wait(&mc.waitq, &wait, TASK_INTERRUPTIBLE);
|
|
/* moving charge context might have finished. */
|
|
if (mc.moving_task)
|
|
schedule();
|
|
finish_wait(&mc.waitq, &wait);
|
|
return true;
|
|
}
|
|
}
|
|
return false;
|
|
}
|
|
|
|
static char *memory_stat_format(struct mem_cgroup *memcg)
|
|
{
|
|
struct seq_buf s;
|
|
int i;
|
|
|
|
seq_buf_init(&s, kmalloc(PAGE_SIZE, GFP_KERNEL), PAGE_SIZE);
|
|
if (!s.buffer)
|
|
return NULL;
|
|
|
|
/*
|
|
* Provide statistics on the state of the memory subsystem as
|
|
* well as cumulative event counters that show past behavior.
|
|
*
|
|
* This list is ordered following a combination of these gradients:
|
|
* 1) generic big picture -> specifics and details
|
|
* 2) reflecting userspace activity -> reflecting kernel heuristics
|
|
*
|
|
* Current memory state:
|
|
*/
|
|
|
|
seq_buf_printf(&s, "anon %llu\n",
|
|
(u64)memcg_page_state(memcg, MEMCG_RSS) *
|
|
PAGE_SIZE);
|
|
seq_buf_printf(&s, "file %llu\n",
|
|
(u64)memcg_page_state(memcg, MEMCG_CACHE) *
|
|
PAGE_SIZE);
|
|
seq_buf_printf(&s, "kernel_stack %llu\n",
|
|
(u64)memcg_page_state(memcg, MEMCG_KERNEL_STACK_KB) *
|
|
1024);
|
|
seq_buf_printf(&s, "slab %llu\n",
|
|
(u64)(memcg_page_state(memcg, NR_SLAB_RECLAIMABLE) +
|
|
memcg_page_state(memcg, NR_SLAB_UNRECLAIMABLE)) *
|
|
PAGE_SIZE);
|
|
seq_buf_printf(&s, "sock %llu\n",
|
|
(u64)memcg_page_state(memcg, MEMCG_SOCK) *
|
|
PAGE_SIZE);
|
|
|
|
seq_buf_printf(&s, "shmem %llu\n",
|
|
(u64)memcg_page_state(memcg, NR_SHMEM) *
|
|
PAGE_SIZE);
|
|
seq_buf_printf(&s, "file_mapped %llu\n",
|
|
(u64)memcg_page_state(memcg, NR_FILE_MAPPED) *
|
|
PAGE_SIZE);
|
|
seq_buf_printf(&s, "file_dirty %llu\n",
|
|
(u64)memcg_page_state(memcg, NR_FILE_DIRTY) *
|
|
PAGE_SIZE);
|
|
seq_buf_printf(&s, "file_writeback %llu\n",
|
|
(u64)memcg_page_state(memcg, NR_WRITEBACK) *
|
|
PAGE_SIZE);
|
|
|
|
/*
|
|
* TODO: We should eventually replace our own MEMCG_RSS_HUGE counter
|
|
* with the NR_ANON_THP vm counter, but right now it's a pain in the
|
|
* arse because it requires migrating the work out of rmap to a place
|
|
* where the page->mem_cgroup is set up and stable.
|
|
*/
|
|
seq_buf_printf(&s, "anon_thp %llu\n",
|
|
(u64)memcg_page_state(memcg, MEMCG_RSS_HUGE) *
|
|
PAGE_SIZE);
|
|
|
|
for (i = 0; i < NR_LRU_LISTS; i++)
|
|
seq_buf_printf(&s, "%s %llu\n", mem_cgroup_lru_names[i],
|
|
(u64)memcg_page_state(memcg, NR_LRU_BASE + i) *
|
|
PAGE_SIZE);
|
|
|
|
seq_buf_printf(&s, "slab_reclaimable %llu\n",
|
|
(u64)memcg_page_state(memcg, NR_SLAB_RECLAIMABLE) *
|
|
PAGE_SIZE);
|
|
seq_buf_printf(&s, "slab_unreclaimable %llu\n",
|
|
(u64)memcg_page_state(memcg, NR_SLAB_UNRECLAIMABLE) *
|
|
PAGE_SIZE);
|
|
|
|
/* Accumulated memory events */
|
|
|
|
seq_buf_printf(&s, "pgfault %lu\n", memcg_events(memcg, PGFAULT));
|
|
seq_buf_printf(&s, "pgmajfault %lu\n", memcg_events(memcg, PGMAJFAULT));
|
|
|
|
seq_buf_printf(&s, "workingset_refault %lu\n",
|
|
memcg_page_state(memcg, WORKINGSET_REFAULT));
|
|
seq_buf_printf(&s, "workingset_activate %lu\n",
|
|
memcg_page_state(memcg, WORKINGSET_ACTIVATE));
|
|
seq_buf_printf(&s, "workingset_nodereclaim %lu\n",
|
|
memcg_page_state(memcg, WORKINGSET_NODERECLAIM));
|
|
|
|
seq_buf_printf(&s, "pgrefill %lu\n", memcg_events(memcg, PGREFILL));
|
|
seq_buf_printf(&s, "pgscan %lu\n",
|
|
memcg_events(memcg, PGSCAN_KSWAPD) +
|
|
memcg_events(memcg, PGSCAN_DIRECT));
|
|
seq_buf_printf(&s, "pgsteal %lu\n",
|
|
memcg_events(memcg, PGSTEAL_KSWAPD) +
|
|
memcg_events(memcg, PGSTEAL_DIRECT));
|
|
seq_buf_printf(&s, "pgactivate %lu\n", memcg_events(memcg, PGACTIVATE));
|
|
seq_buf_printf(&s, "pgdeactivate %lu\n", memcg_events(memcg, PGDEACTIVATE));
|
|
seq_buf_printf(&s, "pglazyfree %lu\n", memcg_events(memcg, PGLAZYFREE));
|
|
seq_buf_printf(&s, "pglazyfreed %lu\n", memcg_events(memcg, PGLAZYFREED));
|
|
|
|
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
|
|
seq_buf_printf(&s, "thp_fault_alloc %lu\n",
|
|
memcg_events(memcg, THP_FAULT_ALLOC));
|
|
seq_buf_printf(&s, "thp_collapse_alloc %lu\n",
|
|
memcg_events(memcg, THP_COLLAPSE_ALLOC));
|
|
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
|
|
|
|
/* The above should easily fit into one page */
|
|
WARN_ON_ONCE(seq_buf_has_overflowed(&s));
|
|
|
|
return s.buffer;
|
|
}
|
|
|
|
#define K(x) ((x) << (PAGE_SHIFT-10))
|
|
/**
|
|
* mem_cgroup_print_oom_context: Print OOM information relevant to
|
|
* memory controller.
|
|
* @memcg: The memory cgroup that went over limit
|
|
* @p: Task that is going to be killed
|
|
*
|
|
* NOTE: @memcg and @p's mem_cgroup can be different when hierarchy is
|
|
* enabled
|
|
*/
|
|
void mem_cgroup_print_oom_context(struct mem_cgroup *memcg, struct task_struct *p)
|
|
{
|
|
rcu_read_lock();
|
|
|
|
if (memcg) {
|
|
pr_cont(",oom_memcg=");
|
|
pr_cont_cgroup_path(memcg->css.cgroup);
|
|
} else
|
|
pr_cont(",global_oom");
|
|
if (p) {
|
|
pr_cont(",task_memcg=");
|
|
pr_cont_cgroup_path(task_cgroup(p, memory_cgrp_id));
|
|
}
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
/**
|
|
* mem_cgroup_print_oom_meminfo: Print OOM memory information relevant to
|
|
* memory controller.
|
|
* @memcg: The memory cgroup that went over limit
|
|
*/
|
|
void mem_cgroup_print_oom_meminfo(struct mem_cgroup *memcg)
|
|
{
|
|
char *buf;
|
|
|
|
pr_info("memory: usage %llukB, limit %llukB, failcnt %lu\n",
|
|
K((u64)page_counter_read(&memcg->memory)),
|
|
K((u64)memcg->memory.max), memcg->memory.failcnt);
|
|
if (cgroup_subsys_on_dfl(memory_cgrp_subsys))
|
|
pr_info("swap: usage %llukB, limit %llukB, failcnt %lu\n",
|
|
K((u64)page_counter_read(&memcg->swap)),
|
|
K((u64)memcg->swap.max), memcg->swap.failcnt);
|
|
else {
|
|
pr_info("memory+swap: usage %llukB, limit %llukB, failcnt %lu\n",
|
|
K((u64)page_counter_read(&memcg->memsw)),
|
|
K((u64)memcg->memsw.max), memcg->memsw.failcnt);
|
|
pr_info("kmem: usage %llukB, limit %llukB, failcnt %lu\n",
|
|
K((u64)page_counter_read(&memcg->kmem)),
|
|
K((u64)memcg->kmem.max), memcg->kmem.failcnt);
|
|
}
|
|
|
|
pr_info("Memory cgroup stats for ");
|
|
pr_cont_cgroup_path(memcg->css.cgroup);
|
|
pr_cont(":");
|
|
buf = memory_stat_format(memcg);
|
|
if (!buf)
|
|
return;
|
|
pr_info("%s", buf);
|
|
kfree(buf);
|
|
}
|
|
|
|
/*
|
|
* Return the memory (and swap, if configured) limit for a memcg.
|
|
*/
|
|
unsigned long mem_cgroup_get_max(struct mem_cgroup *memcg)
|
|
{
|
|
unsigned long max;
|
|
|
|
max = memcg->memory.max;
|
|
if (mem_cgroup_swappiness(memcg)) {
|
|
unsigned long memsw_max;
|
|
unsigned long swap_max;
|
|
|
|
memsw_max = memcg->memsw.max;
|
|
swap_max = memcg->swap.max;
|
|
swap_max = min(swap_max, (unsigned long)total_swap_pages);
|
|
max = min(max + swap_max, memsw_max);
|
|
}
|
|
return max;
|
|
}
|
|
|
|
unsigned long mem_cgroup_size(struct mem_cgroup *memcg)
|
|
{
|
|
return page_counter_read(&memcg->memory);
|
|
}
|
|
|
|
static bool mem_cgroup_out_of_memory(struct mem_cgroup *memcg, gfp_t gfp_mask,
|
|
int order)
|
|
{
|
|
struct oom_control oc = {
|
|
.zonelist = NULL,
|
|
.nodemask = NULL,
|
|
.memcg = memcg,
|
|
.gfp_mask = gfp_mask,
|
|
.order = order,
|
|
};
|
|
bool ret;
|
|
|
|
if (mutex_lock_killable(&oom_lock))
|
|
return true;
|
|
/*
|
|
* A few threads which were not waiting at mutex_lock_killable() can
|
|
* fail to bail out. Therefore, check again after holding oom_lock.
|
|
*/
|
|
ret = should_force_charge() || out_of_memory(&oc);
|
|
mutex_unlock(&oom_lock);
|
|
return ret;
|
|
}
|
|
|
|
#if MAX_NUMNODES > 1
|
|
|
|
/**
|
|
* test_mem_cgroup_node_reclaimable
|
|
* @memcg: the target memcg
|
|
* @nid: the node ID to be checked.
|
|
* @noswap : specify true here if the user wants flle only information.
|
|
*
|
|
* This function returns whether the specified memcg contains any
|
|
* reclaimable pages on a node. Returns true if there are any reclaimable
|
|
* pages in the node.
|
|
*/
|
|
static bool test_mem_cgroup_node_reclaimable(struct mem_cgroup *memcg,
|
|
int nid, bool noswap)
|
|
{
|
|
struct lruvec *lruvec = mem_cgroup_lruvec(NODE_DATA(nid), memcg);
|
|
|
|
if (lruvec_page_state(lruvec, NR_INACTIVE_FILE) ||
|
|
lruvec_page_state(lruvec, NR_ACTIVE_FILE))
|
|
return true;
|
|
if (noswap || !total_swap_pages)
|
|
return false;
|
|
if (lruvec_page_state(lruvec, NR_INACTIVE_ANON) ||
|
|
lruvec_page_state(lruvec, NR_ACTIVE_ANON))
|
|
return true;
|
|
return false;
|
|
|
|
}
|
|
|
|
/*
|
|
* Always updating the nodemask is not very good - even if we have an empty
|
|
* list or the wrong list here, we can start from some node and traverse all
|
|
* nodes based on the zonelist. So update the list loosely once per 10 secs.
|
|
*
|
|
*/
|
|
static void mem_cgroup_may_update_nodemask(struct mem_cgroup *memcg)
|
|
{
|
|
int nid;
|
|
/*
|
|
* numainfo_events > 0 means there was at least NUMAINFO_EVENTS_TARGET
|
|
* pagein/pageout changes since the last update.
|
|
*/
|
|
if (!atomic_read(&memcg->numainfo_events))
|
|
return;
|
|
if (atomic_inc_return(&memcg->numainfo_updating) > 1)
|
|
return;
|
|
|
|
/* make a nodemask where this memcg uses memory from */
|
|
memcg->scan_nodes = node_states[N_MEMORY];
|
|
|
|
for_each_node_mask(nid, node_states[N_MEMORY]) {
|
|
|
|
if (!test_mem_cgroup_node_reclaimable(memcg, nid, false))
|
|
node_clear(nid, memcg->scan_nodes);
|
|
}
|
|
|
|
atomic_set(&memcg->numainfo_events, 0);
|
|
atomic_set(&memcg->numainfo_updating, 0);
|
|
}
|
|
|
|
/*
|
|
* Selecting a node where we start reclaim from. Because what we need is just
|
|
* reducing usage counter, start from anywhere is O,K. Considering
|
|
* memory reclaim from current node, there are pros. and cons.
|
|
*
|
|
* Freeing memory from current node means freeing memory from a node which
|
|
* we'll use or we've used. So, it may make LRU bad. And if several threads
|
|
* hit limits, it will see a contention on a node. But freeing from remote
|
|
* node means more costs for memory reclaim because of memory latency.
|
|
*
|
|
* Now, we use round-robin. Better algorithm is welcomed.
|
|
*/
|
|
int mem_cgroup_select_victim_node(struct mem_cgroup *memcg)
|
|
{
|
|
int node;
|
|
|
|
mem_cgroup_may_update_nodemask(memcg);
|
|
node = memcg->last_scanned_node;
|
|
|
|
node = next_node_in(node, memcg->scan_nodes);
|
|
/*
|
|
* mem_cgroup_may_update_nodemask might have seen no reclaimmable pages
|
|
* last time it really checked all the LRUs due to rate limiting.
|
|
* Fallback to the current node in that case for simplicity.
|
|
*/
|
|
if (unlikely(node == MAX_NUMNODES))
|
|
node = numa_node_id();
|
|
|
|
memcg->last_scanned_node = node;
|
|
return node;
|
|
}
|
|
#else
|
|
int mem_cgroup_select_victim_node(struct mem_cgroup *memcg)
|
|
{
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
static int mem_cgroup_soft_reclaim(struct mem_cgroup *root_memcg,
|
|
pg_data_t *pgdat,
|
|
gfp_t gfp_mask,
|
|
unsigned long *total_scanned)
|
|
{
|
|
struct mem_cgroup *victim = NULL;
|
|
int total = 0;
|
|
int loop = 0;
|
|
unsigned long excess;
|
|
unsigned long nr_scanned;
|
|
struct mem_cgroup_reclaim_cookie reclaim = {
|
|
.pgdat = pgdat,
|
|
.priority = 0,
|
|
};
|
|
|
|
excess = soft_limit_excess(root_memcg);
|
|
|
|
while (1) {
|
|
victim = mem_cgroup_iter(root_memcg, victim, &reclaim);
|
|
if (!victim) {
|
|
loop++;
|
|
if (loop >= 2) {
|
|
/*
|
|
* If we have not been able to reclaim
|
|
* anything, it might because there are
|
|
* no reclaimable pages under this hierarchy
|
|
*/
|
|
if (!total)
|
|
break;
|
|
/*
|
|
* We want to do more targeted reclaim.
|
|
* excess >> 2 is not to excessive so as to
|
|
* reclaim too much, nor too less that we keep
|
|
* coming back to reclaim from this cgroup
|
|
*/
|
|
if (total >= (excess >> 2) ||
|
|
(loop > MEM_CGROUP_MAX_RECLAIM_LOOPS))
|
|
break;
|
|
}
|
|
continue;
|
|
}
|
|
total += mem_cgroup_shrink_node(victim, gfp_mask, false,
|
|
pgdat, &nr_scanned);
|
|
*total_scanned += nr_scanned;
|
|
if (!soft_limit_excess(root_memcg))
|
|
break;
|
|
}
|
|
mem_cgroup_iter_break(root_memcg, victim);
|
|
return total;
|
|
}
|
|
|
|
#ifdef CONFIG_LOCKDEP
|
|
static struct lockdep_map memcg_oom_lock_dep_map = {
|
|
.name = "memcg_oom_lock",
|
|
};
|
|
#endif
|
|
|
|
static DEFINE_SPINLOCK(memcg_oom_lock);
|
|
|
|
/*
|
|
* Check OOM-Killer is already running under our hierarchy.
|
|
* If someone is running, return false.
|
|
*/
|
|
static bool mem_cgroup_oom_trylock(struct mem_cgroup *memcg)
|
|
{
|
|
struct mem_cgroup *iter, *failed = NULL;
|
|
|
|
spin_lock(&memcg_oom_lock);
|
|
|
|
for_each_mem_cgroup_tree(iter, memcg) {
|
|
if (iter->oom_lock) {
|
|
/*
|
|
* this subtree of our hierarchy is already locked
|
|
* so we cannot give a lock.
|
|
*/
|
|
failed = iter;
|
|
mem_cgroup_iter_break(memcg, iter);
|
|
break;
|
|
} else
|
|
iter->oom_lock = true;
|
|
}
|
|
|
|
if (failed) {
|
|
/*
|
|
* OK, we failed to lock the whole subtree so we have
|
|
* to clean up what we set up to the failing subtree
|
|
*/
|
|
for_each_mem_cgroup_tree(iter, memcg) {
|
|
if (iter == failed) {
|
|
mem_cgroup_iter_break(memcg, iter);
|
|
break;
|
|
}
|
|
iter->oom_lock = false;
|
|
}
|
|
} else
|
|
mutex_acquire(&memcg_oom_lock_dep_map, 0, 1, _RET_IP_);
|
|
|
|
spin_unlock(&memcg_oom_lock);
|
|
|
|
return !failed;
|
|
}
|
|
|
|
static void mem_cgroup_oom_unlock(struct mem_cgroup *memcg)
|
|
{
|
|
struct mem_cgroup *iter;
|
|
|
|
spin_lock(&memcg_oom_lock);
|
|
mutex_release(&memcg_oom_lock_dep_map, 1, _RET_IP_);
|
|
for_each_mem_cgroup_tree(iter, memcg)
|
|
iter->oom_lock = false;
|
|
spin_unlock(&memcg_oom_lock);
|
|
}
|
|
|
|
static void mem_cgroup_mark_under_oom(struct mem_cgroup *memcg)
|
|
{
|
|
struct mem_cgroup *iter;
|
|
|
|
spin_lock(&memcg_oom_lock);
|
|
for_each_mem_cgroup_tree(iter, memcg)
|
|
iter->under_oom++;
|
|
spin_unlock(&memcg_oom_lock);
|
|
}
|
|
|
|
static void mem_cgroup_unmark_under_oom(struct mem_cgroup *memcg)
|
|
{
|
|
struct mem_cgroup *iter;
|
|
|
|
/*
|
|
* When a new child is created while the hierarchy is under oom,
|
|
* mem_cgroup_oom_lock() may not be called. Watch for underflow.
|
|
*/
|
|
spin_lock(&memcg_oom_lock);
|
|
for_each_mem_cgroup_tree(iter, memcg)
|
|
if (iter->under_oom > 0)
|
|
iter->under_oom--;
|
|
spin_unlock(&memcg_oom_lock);
|
|
}
|
|
|
|
static DECLARE_WAIT_QUEUE_HEAD(memcg_oom_waitq);
|
|
|
|
struct oom_wait_info {
|
|
struct mem_cgroup *memcg;
|
|
wait_queue_entry_t wait;
|
|
};
|
|
|
|
static int memcg_oom_wake_function(wait_queue_entry_t *wait,
|
|
unsigned mode, int sync, void *arg)
|
|
{
|
|
struct mem_cgroup *wake_memcg = (struct mem_cgroup *)arg;
|
|
struct mem_cgroup *oom_wait_memcg;
|
|
struct oom_wait_info *oom_wait_info;
|
|
|
|
oom_wait_info = container_of(wait, struct oom_wait_info, wait);
|
|
oom_wait_memcg = oom_wait_info->memcg;
|
|
|
|
if (!mem_cgroup_is_descendant(wake_memcg, oom_wait_memcg) &&
|
|
!mem_cgroup_is_descendant(oom_wait_memcg, wake_memcg))
|
|
return 0;
|
|
return autoremove_wake_function(wait, mode, sync, arg);
|
|
}
|
|
|
|
static void memcg_oom_recover(struct mem_cgroup *memcg)
|
|
{
|
|
/*
|
|
* For the following lockless ->under_oom test, the only required
|
|
* guarantee is that it must see the state asserted by an OOM when
|
|
* this function is called as a result of userland actions
|
|
* triggered by the notification of the OOM. This is trivially
|
|
* achieved by invoking mem_cgroup_mark_under_oom() before
|
|
* triggering notification.
|
|
*/
|
|
if (memcg && memcg->under_oom)
|
|
__wake_up(&memcg_oom_waitq, TASK_NORMAL, 0, memcg);
|
|
}
|
|
|
|
enum oom_status {
|
|
OOM_SUCCESS,
|
|
OOM_FAILED,
|
|
OOM_ASYNC,
|
|
OOM_SKIPPED
|
|
};
|
|
|
|
static enum oom_status mem_cgroup_oom(struct mem_cgroup *memcg, gfp_t mask, int order)
|
|
{
|
|
enum oom_status ret;
|
|
bool locked;
|
|
|
|
if (order > PAGE_ALLOC_COSTLY_ORDER)
|
|
return OOM_SKIPPED;
|
|
|
|
memcg_memory_event(memcg, MEMCG_OOM);
|
|
|
|
/*
|
|
* We are in the middle of the charge context here, so we
|
|
* don't want to block when potentially sitting on a callstack
|
|
* that holds all kinds of filesystem and mm locks.
|
|
*
|
|
* cgroup1 allows disabling the OOM killer and waiting for outside
|
|
* handling until the charge can succeed; remember the context and put
|
|
* the task to sleep at the end of the page fault when all locks are
|
|
* released.
|
|
*
|
|
* On the other hand, in-kernel OOM killer allows for an async victim
|
|
* memory reclaim (oom_reaper) and that means that we are not solely
|
|
* relying on the oom victim to make a forward progress and we can
|
|
* invoke the oom killer here.
|
|
*
|
|
* Please note that mem_cgroup_out_of_memory might fail to find a
|
|
* victim and then we have to bail out from the charge path.
|
|
*/
|
|
if (memcg->oom_kill_disable) {
|
|
if (!current->in_user_fault)
|
|
return OOM_SKIPPED;
|
|
css_get(&memcg->css);
|
|
current->memcg_in_oom = memcg;
|
|
current->memcg_oom_gfp_mask = mask;
|
|
current->memcg_oom_order = order;
|
|
|
|
return OOM_ASYNC;
|
|
}
|
|
|
|
mem_cgroup_mark_under_oom(memcg);
|
|
|
|
locked = mem_cgroup_oom_trylock(memcg);
|
|
|
|
if (locked)
|
|
mem_cgroup_oom_notify(memcg);
|
|
|
|
mem_cgroup_unmark_under_oom(memcg);
|
|
if (mem_cgroup_out_of_memory(memcg, mask, order))
|
|
ret = OOM_SUCCESS;
|
|
else
|
|
ret = OOM_FAILED;
|
|
|
|
if (locked)
|
|
mem_cgroup_oom_unlock(memcg);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* mem_cgroup_oom_synchronize - complete memcg OOM handling
|
|
* @handle: actually kill/wait or just clean up the OOM state
|
|
*
|
|
* This has to be called at the end of a page fault if the memcg OOM
|
|
* handler was enabled.
|
|
*
|
|
* Memcg supports userspace OOM handling where failed allocations must
|
|
* sleep on a waitqueue until the userspace task resolves the
|
|
* situation. Sleeping directly in the charge context with all kinds
|
|
* of locks held is not a good idea, instead we remember an OOM state
|
|
* in the task and mem_cgroup_oom_synchronize() has to be called at
|
|
* the end of the page fault to complete the OOM handling.
|
|
*
|
|
* Returns %true if an ongoing memcg OOM situation was detected and
|
|
* completed, %false otherwise.
|
|
*/
|
|
bool mem_cgroup_oom_synchronize(bool handle)
|
|
{
|
|
struct mem_cgroup *memcg = current->memcg_in_oom;
|
|
struct oom_wait_info owait;
|
|
bool locked;
|
|
|
|
/* OOM is global, do not handle */
|
|
if (!memcg)
|
|
return false;
|
|
|
|
if (!handle)
|
|
goto cleanup;
|
|
|
|
owait.memcg = memcg;
|
|
owait.wait.flags = 0;
|
|
owait.wait.func = memcg_oom_wake_function;
|
|
owait.wait.private = current;
|
|
INIT_LIST_HEAD(&owait.wait.entry);
|
|
|
|
prepare_to_wait(&memcg_oom_waitq, &owait.wait, TASK_KILLABLE);
|
|
mem_cgroup_mark_under_oom(memcg);
|
|
|
|
locked = mem_cgroup_oom_trylock(memcg);
|
|
|
|
if (locked)
|
|
mem_cgroup_oom_notify(memcg);
|
|
|
|
if (locked && !memcg->oom_kill_disable) {
|
|
mem_cgroup_unmark_under_oom(memcg);
|
|
finish_wait(&memcg_oom_waitq, &owait.wait);
|
|
mem_cgroup_out_of_memory(memcg, current->memcg_oom_gfp_mask,
|
|
current->memcg_oom_order);
|
|
} else {
|
|
schedule();
|
|
mem_cgroup_unmark_under_oom(memcg);
|
|
finish_wait(&memcg_oom_waitq, &owait.wait);
|
|
}
|
|
|
|
if (locked) {
|
|
mem_cgroup_oom_unlock(memcg);
|
|
/*
|
|
* There is no guarantee that an OOM-lock contender
|
|
* sees the wakeups triggered by the OOM kill
|
|
* uncharges. Wake any sleepers explicitely.
|
|
*/
|
|
memcg_oom_recover(memcg);
|
|
}
|
|
cleanup:
|
|
current->memcg_in_oom = NULL;
|
|
css_put(&memcg->css);
|
|
return true;
|
|
}
|
|
|
|
/**
|
|
* mem_cgroup_get_oom_group - get a memory cgroup to clean up after OOM
|
|
* @victim: task to be killed by the OOM killer
|
|
* @oom_domain: memcg in case of memcg OOM, NULL in case of system-wide OOM
|
|
*
|
|
* Returns a pointer to a memory cgroup, which has to be cleaned up
|
|
* by killing all belonging OOM-killable tasks.
|
|
*
|
|
* Caller has to call mem_cgroup_put() on the returned non-NULL memcg.
|
|
*/
|
|
struct mem_cgroup *mem_cgroup_get_oom_group(struct task_struct *victim,
|
|
struct mem_cgroup *oom_domain)
|
|
{
|
|
struct mem_cgroup *oom_group = NULL;
|
|
struct mem_cgroup *memcg;
|
|
|
|
if (!cgroup_subsys_on_dfl(memory_cgrp_subsys))
|
|
return NULL;
|
|
|
|
if (!oom_domain)
|
|
oom_domain = root_mem_cgroup;
|
|
|
|
rcu_read_lock();
|
|
|
|
memcg = mem_cgroup_from_task(victim);
|
|
if (memcg == root_mem_cgroup)
|
|
goto out;
|
|
|
|
/*
|
|
* Traverse the memory cgroup hierarchy from the victim task's
|
|
* cgroup up to the OOMing cgroup (or root) to find the
|
|
* highest-level memory cgroup with oom.group set.
|
|
*/
|
|
for (; memcg; memcg = parent_mem_cgroup(memcg)) {
|
|
if (memcg->oom_group)
|
|
oom_group = memcg;
|
|
|
|
if (memcg == oom_domain)
|
|
break;
|
|
}
|
|
|
|
if (oom_group)
|
|
css_get(&oom_group->css);
|
|
out:
|
|
rcu_read_unlock();
|
|
|
|
return oom_group;
|
|
}
|
|
|
|
void mem_cgroup_print_oom_group(struct mem_cgroup *memcg)
|
|
{
|
|
pr_info("Tasks in ");
|
|
pr_cont_cgroup_path(memcg->css.cgroup);
|
|
pr_cont(" are going to be killed due to memory.oom.group set\n");
|
|
}
|
|
|
|
/**
|
|
* lock_page_memcg - lock a page->mem_cgroup binding
|
|
* @page: the page
|
|
*
|
|
* This function protects unlocked LRU pages from being moved to
|
|
* another cgroup.
|
|
*
|
|
* It ensures lifetime of the returned memcg. Caller is responsible
|
|
* for the lifetime of the page; __unlock_page_memcg() is available
|
|
* when @page might get freed inside the locked section.
|
|
*/
|
|
struct mem_cgroup *lock_page_memcg(struct page *page)
|
|
{
|
|
struct mem_cgroup *memcg;
|
|
unsigned long flags;
|
|
|
|
/*
|
|
* The RCU lock is held throughout the transaction. The fast
|
|
* path can get away without acquiring the memcg->move_lock
|
|
* because page moving starts with an RCU grace period.
|
|
*
|
|
* The RCU lock also protects the memcg from being freed when
|
|
* the page state that is going to change is the only thing
|
|
* preventing the page itself from being freed. E.g. writeback
|
|
* doesn't hold a page reference and relies on PG_writeback to
|
|
* keep off truncation, migration and so forth.
|
|
*/
|
|
rcu_read_lock();
|
|
|
|
if (mem_cgroup_disabled())
|
|
return NULL;
|
|
again:
|
|
memcg = page->mem_cgroup;
|
|
if (unlikely(!memcg))
|
|
return NULL;
|
|
|
|
if (atomic_read(&memcg->moving_account) <= 0)
|
|
return memcg;
|
|
|
|
spin_lock_irqsave(&memcg->move_lock, flags);
|
|
if (memcg != page->mem_cgroup) {
|
|
spin_unlock_irqrestore(&memcg->move_lock, flags);
|
|
goto again;
|
|
}
|
|
|
|
/*
|
|
* When charge migration first begins, we can have locked and
|
|
* unlocked page stat updates happening concurrently. Track
|
|
* the task who has the lock for unlock_page_memcg().
|
|
*/
|
|
memcg->move_lock_task = current;
|
|
memcg->move_lock_flags = flags;
|
|
|
|
return memcg;
|
|
}
|
|
EXPORT_SYMBOL(lock_page_memcg);
|
|
|
|
/**
|
|
* __unlock_page_memcg - unlock and unpin a memcg
|
|
* @memcg: the memcg
|
|
*
|
|
* Unlock and unpin a memcg returned by lock_page_memcg().
|
|
*/
|
|
void __unlock_page_memcg(struct mem_cgroup *memcg)
|
|
{
|
|
if (memcg && memcg->move_lock_task == current) {
|
|
unsigned long flags = memcg->move_lock_flags;
|
|
|
|
memcg->move_lock_task = NULL;
|
|
memcg->move_lock_flags = 0;
|
|
|
|
spin_unlock_irqrestore(&memcg->move_lock, flags);
|
|
}
|
|
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
/**
|
|
* unlock_page_memcg - unlock a page->mem_cgroup binding
|
|
* @page: the page
|
|
*/
|
|
void unlock_page_memcg(struct page *page)
|
|
{
|
|
__unlock_page_memcg(page->mem_cgroup);
|
|
}
|
|
EXPORT_SYMBOL(unlock_page_memcg);
|
|
|
|
struct memcg_stock_pcp {
|
|
struct mem_cgroup *cached; /* this never be root cgroup */
|
|
unsigned int nr_pages;
|
|
struct work_struct work;
|
|
unsigned long flags;
|
|
#define FLUSHING_CACHED_CHARGE 0
|
|
};
|
|
static DEFINE_PER_CPU(struct memcg_stock_pcp, memcg_stock);
|
|
static DEFINE_MUTEX(percpu_charge_mutex);
|
|
|
|
/**
|
|
* consume_stock: Try to consume stocked charge on this cpu.
|
|
* @memcg: memcg to consume from.
|
|
* @nr_pages: how many pages to charge.
|
|
*
|
|
* The charges will only happen if @memcg matches the current cpu's memcg
|
|
* stock, and at least @nr_pages are available in that stock. Failure to
|
|
* service an allocation will refill the stock.
|
|
*
|
|
* returns true if successful, false otherwise.
|
|
*/
|
|
static bool consume_stock(struct mem_cgroup *memcg, unsigned int nr_pages)
|
|
{
|
|
struct memcg_stock_pcp *stock;
|
|
unsigned long flags;
|
|
bool ret = false;
|
|
|
|
if (nr_pages > MEMCG_CHARGE_BATCH)
|
|
return ret;
|
|
|
|
local_irq_save(flags);
|
|
|
|
stock = this_cpu_ptr(&memcg_stock);
|
|
if (memcg == stock->cached && stock->nr_pages >= nr_pages) {
|
|
stock->nr_pages -= nr_pages;
|
|
ret = true;
|
|
}
|
|
|
|
local_irq_restore(flags);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Returns stocks cached in percpu and reset cached information.
|
|
*/
|
|
static void drain_stock(struct memcg_stock_pcp *stock)
|
|
{
|
|
struct mem_cgroup *old = stock->cached;
|
|
|
|
if (stock->nr_pages) {
|
|
page_counter_uncharge(&old->memory, stock->nr_pages);
|
|
if (do_memsw_account())
|
|
page_counter_uncharge(&old->memsw, stock->nr_pages);
|
|
css_put_many(&old->css, stock->nr_pages);
|
|
stock->nr_pages = 0;
|
|
}
|
|
stock->cached = NULL;
|
|
}
|
|
|
|
static void drain_local_stock(struct work_struct *dummy)
|
|
{
|
|
struct memcg_stock_pcp *stock;
|
|
unsigned long flags;
|
|
|
|
/*
|
|
* The only protection from memory hotplug vs. drain_stock races is
|
|
* that we always operate on local CPU stock here with IRQ disabled
|
|
*/
|
|
local_irq_save(flags);
|
|
|
|
stock = this_cpu_ptr(&memcg_stock);
|
|
drain_stock(stock);
|
|
clear_bit(FLUSHING_CACHED_CHARGE, &stock->flags);
|
|
|
|
local_irq_restore(flags);
|
|
}
|
|
|
|
/*
|
|
* Cache charges(val) to local per_cpu area.
|
|
* This will be consumed by consume_stock() function, later.
|
|
*/
|
|
static void refill_stock(struct mem_cgroup *memcg, unsigned int nr_pages)
|
|
{
|
|
struct memcg_stock_pcp *stock;
|
|
unsigned long flags;
|
|
|
|
local_irq_save(flags);
|
|
|
|
stock = this_cpu_ptr(&memcg_stock);
|
|
if (stock->cached != memcg) { /* reset if necessary */
|
|
drain_stock(stock);
|
|
stock->cached = memcg;
|
|
}
|
|
stock->nr_pages += nr_pages;
|
|
|
|
if (stock->nr_pages > MEMCG_CHARGE_BATCH)
|
|
drain_stock(stock);
|
|
|
|
local_irq_restore(flags);
|
|
}
|
|
|
|
/*
|
|
* Drains all per-CPU charge caches for given root_memcg resp. subtree
|
|
* of the hierarchy under it.
|
|
*/
|
|
static void drain_all_stock(struct mem_cgroup *root_memcg)
|
|
{
|
|
int cpu, curcpu;
|
|
|
|
/* If someone's already draining, avoid adding running more workers. */
|
|
if (!mutex_trylock(&percpu_charge_mutex))
|
|
return;
|
|
/*
|
|
* Notify other cpus that system-wide "drain" is running
|
|
* We do not care about races with the cpu hotplug because cpu down
|
|
* as well as workers from this path always operate on the local
|
|
* per-cpu data. CPU up doesn't touch memcg_stock at all.
|
|
*/
|
|
curcpu = get_cpu();
|
|
for_each_online_cpu(cpu) {
|
|
struct memcg_stock_pcp *stock = &per_cpu(memcg_stock, cpu);
|
|
struct mem_cgroup *memcg;
|
|
bool flush = false;
|
|
|
|
rcu_read_lock();
|
|
memcg = stock->cached;
|
|
if (memcg && stock->nr_pages &&
|
|
mem_cgroup_is_descendant(memcg, root_memcg))
|
|
flush = true;
|
|
rcu_read_unlock();
|
|
|
|
if (flush &&
|
|
!test_and_set_bit(FLUSHING_CACHED_CHARGE, &stock->flags)) {
|
|
if (cpu == curcpu)
|
|
drain_local_stock(&stock->work);
|
|
else
|
|
schedule_work_on(cpu, &stock->work);
|
|
}
|
|
}
|
|
put_cpu();
|
|
mutex_unlock(&percpu_charge_mutex);
|
|
}
|
|
|
|
static int memcg_hotplug_cpu_dead(unsigned int cpu)
|
|
{
|
|
struct memcg_stock_pcp *stock;
|
|
struct mem_cgroup *memcg, *mi;
|
|
|
|
stock = &per_cpu(memcg_stock, cpu);
|
|
drain_stock(stock);
|
|
|
|
for_each_mem_cgroup(memcg) {
|
|
int i;
|
|
|
|
for (i = 0; i < MEMCG_NR_STAT; i++) {
|
|
int nid;
|
|
long x;
|
|
|
|
x = this_cpu_xchg(memcg->vmstats_percpu->stat[i], 0);
|
|
if (x)
|
|
for (mi = memcg; mi; mi = parent_mem_cgroup(mi))
|
|
atomic_long_add(x, &memcg->vmstats[i]);
|
|
|
|
if (i >= NR_VM_NODE_STAT_ITEMS)
|
|
continue;
|
|
|
|
for_each_node(nid) {
|
|
struct mem_cgroup_per_node *pn;
|
|
|
|
pn = mem_cgroup_nodeinfo(memcg, nid);
|
|
x = this_cpu_xchg(pn->lruvec_stat_cpu->count[i], 0);
|
|
if (x)
|
|
do {
|
|
atomic_long_add(x, &pn->lruvec_stat[i]);
|
|
} while ((pn = parent_nodeinfo(pn, nid)));
|
|
}
|
|
}
|
|
|
|
for (i = 0; i < NR_VM_EVENT_ITEMS; i++) {
|
|
long x;
|
|
|
|
x = this_cpu_xchg(memcg->vmstats_percpu->events[i], 0);
|
|
if (x)
|
|
for (mi = memcg; mi; mi = parent_mem_cgroup(mi))
|
|
atomic_long_add(x, &memcg->vmevents[i]);
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void reclaim_high(struct mem_cgroup *memcg,
|
|
unsigned int nr_pages,
|
|
gfp_t gfp_mask)
|
|
{
|
|
do {
|
|
if (page_counter_read(&memcg->memory) <= memcg->high)
|
|
continue;
|
|
memcg_memory_event(memcg, MEMCG_HIGH);
|
|
try_to_free_mem_cgroup_pages(memcg, nr_pages, gfp_mask, true);
|
|
} while ((memcg = parent_mem_cgroup(memcg)));
|
|
}
|
|
|
|
static void high_work_func(struct work_struct *work)
|
|
{
|
|
struct mem_cgroup *memcg;
|
|
|
|
memcg = container_of(work, struct mem_cgroup, high_work);
|
|
reclaim_high(memcg, MEMCG_CHARGE_BATCH, GFP_KERNEL);
|
|
}
|
|
|
|
/*
|
|
* Clamp the maximum sleep time per allocation batch to 2 seconds. This is
|
|
* enough to still cause a significant slowdown in most cases, while still
|
|
* allowing diagnostics and tracing to proceed without becoming stuck.
|
|
*/
|
|
#define MEMCG_MAX_HIGH_DELAY_JIFFIES (2UL*HZ)
|
|
|
|
/*
|
|
* When calculating the delay, we use these either side of the exponentiation to
|
|
* maintain precision and scale to a reasonable number of jiffies (see the table
|
|
* below.
|
|
*
|
|
* - MEMCG_DELAY_PRECISION_SHIFT: Extra precision bits while translating the
|
|
* overage ratio to a delay.
|
|
* - MEMCG_DELAY_SCALING_SHIFT: The number of bits to scale down down the
|
|
* proposed penalty in order to reduce to a reasonable number of jiffies, and
|
|
* to produce a reasonable delay curve.
|
|
*
|
|
* MEMCG_DELAY_SCALING_SHIFT just happens to be a number that produces a
|
|
* reasonable delay curve compared to precision-adjusted overage, not
|
|
* penalising heavily at first, but still making sure that growth beyond the
|
|
* limit penalises misbehaviour cgroups by slowing them down exponentially. For
|
|
* example, with a high of 100 megabytes:
|
|
*
|
|
* +-------+------------------------+
|
|
* | usage | time to allocate in ms |
|
|
* +-------+------------------------+
|
|
* | 100M | 0 |
|
|
* | 101M | 6 |
|
|
* | 102M | 25 |
|
|
* | 103M | 57 |
|
|
* | 104M | 102 |
|
|
* | 105M | 159 |
|
|
* | 106M | 230 |
|
|
* | 107M | 313 |
|
|
* | 108M | 409 |
|
|
* | 109M | 518 |
|
|
* | 110M | 639 |
|
|
* | 111M | 774 |
|
|
* | 112M | 921 |
|
|
* | 113M | 1081 |
|
|
* | 114M | 1254 |
|
|
* | 115M | 1439 |
|
|
* | 116M | 1638 |
|
|
* | 117M | 1849 |
|
|
* | 118M | 2000 |
|
|
* | 119M | 2000 |
|
|
* | 120M | 2000 |
|
|
* +-------+------------------------+
|
|
*/
|
|
#define MEMCG_DELAY_PRECISION_SHIFT 20
|
|
#define MEMCG_DELAY_SCALING_SHIFT 14
|
|
|
|
/*
|
|
* Scheduled by try_charge() to be executed from the userland return path
|
|
* and reclaims memory over the high limit.
|
|
*/
|
|
void mem_cgroup_handle_over_high(void)
|
|
{
|
|
unsigned long usage, high, clamped_high;
|
|
unsigned long pflags;
|
|
unsigned long penalty_jiffies, overage;
|
|
unsigned int nr_pages = current->memcg_nr_pages_over_high;
|
|
struct mem_cgroup *memcg;
|
|
|
|
if (likely(!nr_pages))
|
|
return;
|
|
|
|
memcg = get_mem_cgroup_from_mm(current->mm);
|
|
reclaim_high(memcg, nr_pages, GFP_KERNEL);
|
|
current->memcg_nr_pages_over_high = 0;
|
|
|
|
/*
|
|
* memory.high is breached and reclaim is unable to keep up. Throttle
|
|
* allocators proactively to slow down excessive growth.
|
|
*
|
|
* We use overage compared to memory.high to calculate the number of
|
|
* jiffies to sleep (penalty_jiffies). Ideally this value should be
|
|
* fairly lenient on small overages, and increasingly harsh when the
|
|
* memcg in question makes it clear that it has no intention of stopping
|
|
* its crazy behaviour, so we exponentially increase the delay based on
|
|
* overage amount.
|
|
*/
|
|
|
|
usage = page_counter_read(&memcg->memory);
|
|
high = READ_ONCE(memcg->high);
|
|
|
|
if (usage <= high)
|
|
goto out;
|
|
|
|
/*
|
|
* Prevent division by 0 in overage calculation by acting as if it was a
|
|
* threshold of 1 page
|
|
*/
|
|
clamped_high = max(high, 1UL);
|
|
|
|
overage = div_u64((u64)(usage - high) << MEMCG_DELAY_PRECISION_SHIFT,
|
|
clamped_high);
|
|
|
|
penalty_jiffies = ((u64)overage * overage * HZ)
|
|
>> (MEMCG_DELAY_PRECISION_SHIFT + MEMCG_DELAY_SCALING_SHIFT);
|
|
|
|
/*
|
|
* Factor in the task's own contribution to the overage, such that four
|
|
* N-sized allocations are throttled approximately the same as one
|
|
* 4N-sized allocation.
|
|
*
|
|
* MEMCG_CHARGE_BATCH pages is nominal, so work out how much smaller or
|
|
* larger the current charge patch is than that.
|
|
*/
|
|
penalty_jiffies = penalty_jiffies * nr_pages / MEMCG_CHARGE_BATCH;
|
|
|
|
/*
|
|
* Clamp the max delay per usermode return so as to still keep the
|
|
* application moving forwards and also permit diagnostics, albeit
|
|
* extremely slowly.
|
|
*/
|
|
penalty_jiffies = min(penalty_jiffies, MEMCG_MAX_HIGH_DELAY_JIFFIES);
|
|
|
|
/*
|
|
* Don't sleep if the amount of jiffies this memcg owes us is so low
|
|
* that it's not even worth doing, in an attempt to be nice to those who
|
|
* go only a small amount over their memory.high value and maybe haven't
|
|
* been aggressively reclaimed enough yet.
|
|
*/
|
|
if (penalty_jiffies <= HZ / 100)
|
|
goto out;
|
|
|
|
/*
|
|
* If we exit early, we're guaranteed to die (since
|
|
* schedule_timeout_killable sets TASK_KILLABLE). This means we don't
|
|
* need to account for any ill-begotten jiffies to pay them off later.
|
|
*/
|
|
psi_memstall_enter(&pflags);
|
|
schedule_timeout_killable(penalty_jiffies);
|
|
psi_memstall_leave(&pflags);
|
|
|
|
out:
|
|
css_put(&memcg->css);
|
|
}
|
|
|
|
static int try_charge(struct mem_cgroup *memcg, gfp_t gfp_mask,
|
|
unsigned int nr_pages)
|
|
{
|
|
unsigned int batch = max(MEMCG_CHARGE_BATCH, nr_pages);
|
|
int nr_retries = MEM_CGROUP_RECLAIM_RETRIES;
|
|
struct mem_cgroup *mem_over_limit;
|
|
struct page_counter *counter;
|
|
unsigned long nr_reclaimed;
|
|
bool may_swap = true;
|
|
bool drained = false;
|
|
enum oom_status oom_status;
|
|
|
|
if (mem_cgroup_is_root(memcg))
|
|
return 0;
|
|
retry:
|
|
if (consume_stock(memcg, nr_pages))
|
|
return 0;
|
|
|
|
if (!do_memsw_account() ||
|
|
page_counter_try_charge(&memcg->memsw, batch, &counter)) {
|
|
if (page_counter_try_charge(&memcg->memory, batch, &counter))
|
|
goto done_restock;
|
|
if (do_memsw_account())
|
|
page_counter_uncharge(&memcg->memsw, batch);
|
|
mem_over_limit = mem_cgroup_from_counter(counter, memory);
|
|
} else {
|
|
mem_over_limit = mem_cgroup_from_counter(counter, memsw);
|
|
may_swap = false;
|
|
}
|
|
|
|
if (batch > nr_pages) {
|
|
batch = nr_pages;
|
|
goto retry;
|
|
}
|
|
|
|
/*
|
|
* Unlike in global OOM situations, memcg is not in a physical
|
|
* memory shortage. Allow dying and OOM-killed tasks to
|
|
* bypass the last charges so that they can exit quickly and
|
|
* free their memory.
|
|
*/
|
|
if (unlikely(should_force_charge()))
|
|
goto force;
|
|
|
|
/*
|
|
* Prevent unbounded recursion when reclaim operations need to
|
|
* allocate memory. This might exceed the limits temporarily,
|
|
* but we prefer facilitating memory reclaim and getting back
|
|
* under the limit over triggering OOM kills in these cases.
|
|
*/
|
|
if (unlikely(current->flags & PF_MEMALLOC))
|
|
goto force;
|
|
|
|
if (unlikely(task_in_memcg_oom(current)))
|
|
goto nomem;
|
|
|
|
if (!gfpflags_allow_blocking(gfp_mask))
|
|
goto nomem;
|
|
|
|
memcg_memory_event(mem_over_limit, MEMCG_MAX);
|
|
|
|
nr_reclaimed = try_to_free_mem_cgroup_pages(mem_over_limit, nr_pages,
|
|
gfp_mask, may_swap);
|
|
|
|
if (mem_cgroup_margin(mem_over_limit) >= nr_pages)
|
|
goto retry;
|
|
|
|
if (!drained) {
|
|
drain_all_stock(mem_over_limit);
|
|
drained = true;
|
|
goto retry;
|
|
}
|
|
|
|
if (gfp_mask & __GFP_NORETRY)
|
|
goto nomem;
|
|
/*
|
|
* Even though the limit is exceeded at this point, reclaim
|
|
* may have been able to free some pages. Retry the charge
|
|
* before killing the task.
|
|
*
|
|
* Only for regular pages, though: huge pages are rather
|
|
* unlikely to succeed so close to the limit, and we fall back
|
|
* to regular pages anyway in case of failure.
|
|
*/
|
|
if (nr_reclaimed && nr_pages <= (1 << PAGE_ALLOC_COSTLY_ORDER))
|
|
goto retry;
|
|
/*
|
|
* At task move, charge accounts can be doubly counted. So, it's
|
|
* better to wait until the end of task_move if something is going on.
|
|
*/
|
|
if (mem_cgroup_wait_acct_move(mem_over_limit))
|
|
goto retry;
|
|
|
|
if (nr_retries--)
|
|
goto retry;
|
|
|
|
if (gfp_mask & __GFP_RETRY_MAYFAIL)
|
|
goto nomem;
|
|
|
|
if (gfp_mask & __GFP_NOFAIL)
|
|
goto force;
|
|
|
|
if (fatal_signal_pending(current))
|
|
goto force;
|
|
|
|
/*
|
|
* keep retrying as long as the memcg oom killer is able to make
|
|
* a forward progress or bypass the charge if the oom killer
|
|
* couldn't make any progress.
|
|
*/
|
|
oom_status = mem_cgroup_oom(mem_over_limit, gfp_mask,
|
|
get_order(nr_pages * PAGE_SIZE));
|
|
switch (oom_status) {
|
|
case OOM_SUCCESS:
|
|
nr_retries = MEM_CGROUP_RECLAIM_RETRIES;
|
|
goto retry;
|
|
case OOM_FAILED:
|
|
goto force;
|
|
default:
|
|
goto nomem;
|
|
}
|
|
nomem:
|
|
if (!(gfp_mask & __GFP_NOFAIL))
|
|
return -ENOMEM;
|
|
force:
|
|
/*
|
|
* The allocation either can't fail or will lead to more memory
|
|
* being freed very soon. Allow memory usage go over the limit
|
|
* temporarily by force charging it.
|
|
*/
|
|
page_counter_charge(&memcg->memory, nr_pages);
|
|
if (do_memsw_account())
|
|
page_counter_charge(&memcg->memsw, nr_pages);
|
|
css_get_many(&memcg->css, nr_pages);
|
|
|
|
return 0;
|
|
|
|
done_restock:
|
|
css_get_many(&memcg->css, batch);
|
|
if (batch > nr_pages)
|
|
refill_stock(memcg, batch - nr_pages);
|
|
|
|
/*
|
|
* If the hierarchy is above the normal consumption range, schedule
|
|
* reclaim on returning to userland. We can perform reclaim here
|
|
* if __GFP_RECLAIM but let's always punt for simplicity and so that
|
|
* GFP_KERNEL can consistently be used during reclaim. @memcg is
|
|
* not recorded as it most likely matches current's and won't
|
|
* change in the meantime. As high limit is checked again before
|
|
* reclaim, the cost of mismatch is negligible.
|
|
*/
|
|
do {
|
|
if (page_counter_read(&memcg->memory) > memcg->high) {
|
|
/* Don't bother a random interrupted task */
|
|
if (in_interrupt()) {
|
|
schedule_work(&memcg->high_work);
|
|
break;
|
|
}
|
|
current->memcg_nr_pages_over_high += batch;
|
|
set_notify_resume(current);
|
|
break;
|
|
}
|
|
} while ((memcg = parent_mem_cgroup(memcg)));
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void cancel_charge(struct mem_cgroup *memcg, unsigned int nr_pages)
|
|
{
|
|
if (mem_cgroup_is_root(memcg))
|
|
return;
|
|
|
|
page_counter_uncharge(&memcg->memory, nr_pages);
|
|
if (do_memsw_account())
|
|
page_counter_uncharge(&memcg->memsw, nr_pages);
|
|
|
|
css_put_many(&memcg->css, nr_pages);
|
|
}
|
|
|
|
static void lock_page_lru(struct page *page, int *isolated)
|
|
{
|
|
pg_data_t *pgdat = page_pgdat(page);
|
|
|
|
spin_lock_irq(&pgdat->lru_lock);
|
|
if (PageLRU(page)) {
|
|
struct lruvec *lruvec;
|
|
|
|
lruvec = mem_cgroup_page_lruvec(page, pgdat);
|
|
ClearPageLRU(page);
|
|
del_page_from_lru_list(page, lruvec, page_lru(page));
|
|
*isolated = 1;
|
|
} else
|
|
*isolated = 0;
|
|
}
|
|
|
|
static void unlock_page_lru(struct page *page, int isolated)
|
|
{
|
|
pg_data_t *pgdat = page_pgdat(page);
|
|
|
|
if (isolated) {
|
|
struct lruvec *lruvec;
|
|
|
|
lruvec = mem_cgroup_page_lruvec(page, pgdat);
|
|
VM_BUG_ON_PAGE(PageLRU(page), page);
|
|
SetPageLRU(page);
|
|
add_page_to_lru_list(page, lruvec, page_lru(page));
|
|
}
|
|
spin_unlock_irq(&pgdat->lru_lock);
|
|
}
|
|
|
|
static void commit_charge(struct page *page, struct mem_cgroup *memcg,
|
|
bool lrucare)
|
|
{
|
|
int isolated;
|
|
|
|
VM_BUG_ON_PAGE(page->mem_cgroup, page);
|
|
|
|
/*
|
|
* In some cases, SwapCache and FUSE(splice_buf->radixtree), the page
|
|
* may already be on some other mem_cgroup's LRU. Take care of it.
|
|
*/
|
|
if (lrucare)
|
|
lock_page_lru(page, &isolated);
|
|
|
|
/*
|
|
* Nobody should be changing or seriously looking at
|
|
* page->mem_cgroup at this point:
|
|
*
|
|
* - the page is uncharged
|
|
*
|
|
* - the page is off-LRU
|
|
*
|
|
* - an anonymous fault has exclusive page access, except for
|
|
* a locked page table
|
|
*
|
|
* - a page cache insertion, a swapin fault, or a migration
|
|
* have the page locked
|
|
*/
|
|
page->mem_cgroup = memcg;
|
|
|
|
if (lrucare)
|
|
unlock_page_lru(page, isolated);
|
|
}
|
|
|
|
#ifdef CONFIG_MEMCG_KMEM
|
|
static int memcg_alloc_cache_id(void)
|
|
{
|
|
int id, size;
|
|
int err;
|
|
|
|
id = ida_simple_get(&memcg_cache_ida,
|
|
0, MEMCG_CACHES_MAX_SIZE, GFP_KERNEL);
|
|
if (id < 0)
|
|
return id;
|
|
|
|
if (id < memcg_nr_cache_ids)
|
|
return id;
|
|
|
|
/*
|
|
* There's no space for the new id in memcg_caches arrays,
|
|
* so we have to grow them.
|
|
*/
|
|
down_write(&memcg_cache_ids_sem);
|
|
|
|
size = 2 * (id + 1);
|
|
if (size < MEMCG_CACHES_MIN_SIZE)
|
|
size = MEMCG_CACHES_MIN_SIZE;
|
|
else if (size > MEMCG_CACHES_MAX_SIZE)
|
|
size = MEMCG_CACHES_MAX_SIZE;
|
|
|
|
err = memcg_update_all_caches(size);
|
|
if (!err)
|
|
err = memcg_update_all_list_lrus(size);
|
|
if (!err)
|
|
memcg_nr_cache_ids = size;
|
|
|
|
up_write(&memcg_cache_ids_sem);
|
|
|
|
if (err) {
|
|
ida_simple_remove(&memcg_cache_ida, id);
|
|
return err;
|
|
}
|
|
return id;
|
|
}
|
|
|
|
static void memcg_free_cache_id(int id)
|
|
{
|
|
ida_simple_remove(&memcg_cache_ida, id);
|
|
}
|
|
|
|
struct memcg_kmem_cache_create_work {
|
|
struct mem_cgroup *memcg;
|
|
struct kmem_cache *cachep;
|
|
struct work_struct work;
|
|
};
|
|
|
|
static void memcg_kmem_cache_create_func(struct work_struct *w)
|
|
{
|
|
struct memcg_kmem_cache_create_work *cw =
|
|
container_of(w, struct memcg_kmem_cache_create_work, work);
|
|
struct mem_cgroup *memcg = cw->memcg;
|
|
struct kmem_cache *cachep = cw->cachep;
|
|
|
|
memcg_create_kmem_cache(memcg, cachep);
|
|
|
|
css_put(&memcg->css);
|
|
kfree(cw);
|
|
}
|
|
|
|
/*
|
|
* Enqueue the creation of a per-memcg kmem_cache.
|
|
*/
|
|
static void memcg_schedule_kmem_cache_create(struct mem_cgroup *memcg,
|
|
struct kmem_cache *cachep)
|
|
{
|
|
struct memcg_kmem_cache_create_work *cw;
|
|
|
|
if (!css_tryget_online(&memcg->css))
|
|
return;
|
|
|
|
cw = kmalloc(sizeof(*cw), GFP_NOWAIT | __GFP_NOWARN);
|
|
if (!cw)
|
|
return;
|
|
|
|
cw->memcg = memcg;
|
|
cw->cachep = cachep;
|
|
INIT_WORK(&cw->work, memcg_kmem_cache_create_func);
|
|
|
|
queue_work(memcg_kmem_cache_wq, &cw->work);
|
|
}
|
|
|
|
static inline bool memcg_kmem_bypass(void)
|
|
{
|
|
if (in_interrupt() || !current->mm || (current->flags & PF_KTHREAD))
|
|
return true;
|
|
return false;
|
|
}
|
|
|
|
/**
|
|
* memcg_kmem_get_cache: select the correct per-memcg cache for allocation
|
|
* @cachep: the original global kmem cache
|
|
*
|
|
* Return the kmem_cache we're supposed to use for a slab allocation.
|
|
* We try to use the current memcg's version of the cache.
|
|
*
|
|
* If the cache does not exist yet, if we are the first user of it, we
|
|
* create it asynchronously in a workqueue and let the current allocation
|
|
* go through with the original cache.
|
|
*
|
|
* This function takes a reference to the cache it returns to assure it
|
|
* won't get destroyed while we are working with it. Once the caller is
|
|
* done with it, memcg_kmem_put_cache() must be called to release the
|
|
* reference.
|
|
*/
|
|
struct kmem_cache *memcg_kmem_get_cache(struct kmem_cache *cachep)
|
|
{
|
|
struct mem_cgroup *memcg;
|
|
struct kmem_cache *memcg_cachep;
|
|
struct memcg_cache_array *arr;
|
|
int kmemcg_id;
|
|
|
|
VM_BUG_ON(!is_root_cache(cachep));
|
|
|
|
if (memcg_kmem_bypass())
|
|
return cachep;
|
|
|
|
rcu_read_lock();
|
|
|
|
if (unlikely(current->active_memcg))
|
|
memcg = current->active_memcg;
|
|
else
|
|
memcg = mem_cgroup_from_task(current);
|
|
|
|
if (!memcg || memcg == root_mem_cgroup)
|
|
goto out_unlock;
|
|
|
|
kmemcg_id = READ_ONCE(memcg->kmemcg_id);
|
|
if (kmemcg_id < 0)
|
|
goto out_unlock;
|
|
|
|
arr = rcu_dereference(cachep->memcg_params.memcg_caches);
|
|
|
|
/*
|
|
* Make sure we will access the up-to-date value. The code updating
|
|
* memcg_caches issues a write barrier to match the data dependency
|
|
* barrier inside READ_ONCE() (see memcg_create_kmem_cache()).
|
|
*/
|
|
memcg_cachep = READ_ONCE(arr->entries[kmemcg_id]);
|
|
|
|
/*
|
|
* If we are in a safe context (can wait, and not in interrupt
|
|
* context), we could be be predictable and return right away.
|
|
* This would guarantee that the allocation being performed
|
|
* already belongs in the new cache.
|
|
*
|
|
* However, there are some clashes that can arrive from locking.
|
|
* For instance, because we acquire the slab_mutex while doing
|
|
* memcg_create_kmem_cache, this means no further allocation
|
|
* could happen with the slab_mutex held. So it's better to
|
|
* defer everything.
|
|
*
|
|
* If the memcg is dying or memcg_cache is about to be released,
|
|
* don't bother creating new kmem_caches. Because memcg_cachep
|
|
* is ZEROed as the fist step of kmem offlining, we don't need
|
|
* percpu_ref_tryget_live() here. css_tryget_online() check in
|
|
* memcg_schedule_kmem_cache_create() will prevent us from
|
|
* creation of a new kmem_cache.
|
|
*/
|
|
if (unlikely(!memcg_cachep))
|
|
memcg_schedule_kmem_cache_create(memcg, cachep);
|
|
else if (percpu_ref_tryget(&memcg_cachep->memcg_params.refcnt))
|
|
cachep = memcg_cachep;
|
|
out_unlock:
|
|
rcu_read_unlock();
|
|
return cachep;
|
|
}
|
|
|
|
/**
|
|
* memcg_kmem_put_cache: drop reference taken by memcg_kmem_get_cache
|
|
* @cachep: the cache returned by memcg_kmem_get_cache
|
|
*/
|
|
void memcg_kmem_put_cache(struct kmem_cache *cachep)
|
|
{
|
|
if (!is_root_cache(cachep))
|
|
percpu_ref_put(&cachep->memcg_params.refcnt);
|
|
}
|
|
|
|
/**
|
|
* __memcg_kmem_charge_memcg: charge a kmem page
|
|
* @page: page to charge
|
|
* @gfp: reclaim mode
|
|
* @order: allocation order
|
|
* @memcg: memory cgroup to charge
|
|
*
|
|
* Returns 0 on success, an error code on failure.
|
|
*/
|
|
int __memcg_kmem_charge_memcg(struct page *page, gfp_t gfp, int order,
|
|
struct mem_cgroup *memcg)
|
|
{
|
|
unsigned int nr_pages = 1 << order;
|
|
struct page_counter *counter;
|
|
int ret;
|
|
|
|
ret = try_charge(memcg, gfp, nr_pages);
|
|
if (ret)
|
|
return ret;
|
|
|
|
if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) &&
|
|
!page_counter_try_charge(&memcg->kmem, nr_pages, &counter)) {
|
|
|
|
/*
|
|
* Enforce __GFP_NOFAIL allocation because callers are not
|
|
* prepared to see failures and likely do not have any failure
|
|
* handling code.
|
|
*/
|
|
if (gfp & __GFP_NOFAIL) {
|
|
page_counter_charge(&memcg->kmem, nr_pages);
|
|
return 0;
|
|
}
|
|
cancel_charge(memcg, nr_pages);
|
|
return -ENOMEM;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* __memcg_kmem_charge: charge a kmem page to the current memory cgroup
|
|
* @page: page to charge
|
|
* @gfp: reclaim mode
|
|
* @order: allocation order
|
|
*
|
|
* Returns 0 on success, an error code on failure.
|
|
*/
|
|
int __memcg_kmem_charge(struct page *page, gfp_t gfp, int order)
|
|
{
|
|
struct mem_cgroup *memcg;
|
|
int ret = 0;
|
|
|
|
if (memcg_kmem_bypass())
|
|
return 0;
|
|
|
|
memcg = get_mem_cgroup_from_current();
|
|
if (!mem_cgroup_is_root(memcg)) {
|
|
ret = __memcg_kmem_charge_memcg(page, gfp, order, memcg);
|
|
if (!ret) {
|
|
page->mem_cgroup = memcg;
|
|
__SetPageKmemcg(page);
|
|
}
|
|
}
|
|
css_put(&memcg->css);
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* __memcg_kmem_uncharge_memcg: uncharge a kmem page
|
|
* @memcg: memcg to uncharge
|
|
* @nr_pages: number of pages to uncharge
|
|
*/
|
|
void __memcg_kmem_uncharge_memcg(struct mem_cgroup *memcg,
|
|
unsigned int nr_pages)
|
|
{
|
|
if (!cgroup_subsys_on_dfl(memory_cgrp_subsys))
|
|
page_counter_uncharge(&memcg->kmem, nr_pages);
|
|
|
|
page_counter_uncharge(&memcg->memory, nr_pages);
|
|
if (do_memsw_account())
|
|
page_counter_uncharge(&memcg->memsw, nr_pages);
|
|
}
|
|
/**
|
|
* __memcg_kmem_uncharge: uncharge a kmem page
|
|
* @page: page to uncharge
|
|
* @order: allocation order
|
|
*/
|
|
void __memcg_kmem_uncharge(struct page *page, int order)
|
|
{
|
|
struct mem_cgroup *memcg = page->mem_cgroup;
|
|
unsigned int nr_pages = 1 << order;
|
|
|
|
if (!memcg)
|
|
return;
|
|
|
|
VM_BUG_ON_PAGE(mem_cgroup_is_root(memcg), page);
|
|
__memcg_kmem_uncharge_memcg(memcg, nr_pages);
|
|
page->mem_cgroup = NULL;
|
|
|
|
/* slab pages do not have PageKmemcg flag set */
|
|
if (PageKmemcg(page))
|
|
__ClearPageKmemcg(page);
|
|
|
|
css_put_many(&memcg->css, nr_pages);
|
|
}
|
|
#endif /* CONFIG_MEMCG_KMEM */
|
|
|
|
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
|
|
|
|
/*
|
|
* Because tail pages are not marked as "used", set it. We're under
|
|
* pgdat->lru_lock and migration entries setup in all page mappings.
|
|
*/
|
|
void mem_cgroup_split_huge_fixup(struct page *head)
|
|
{
|
|
int i;
|
|
|
|
if (mem_cgroup_disabled())
|
|
return;
|
|
|
|
for (i = 1; i < HPAGE_PMD_NR; i++)
|
|
head[i].mem_cgroup = head->mem_cgroup;
|
|
|
|
__mod_memcg_state(head->mem_cgroup, MEMCG_RSS_HUGE, -HPAGE_PMD_NR);
|
|
}
|
|
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
|
|
|
|
#ifdef CONFIG_MEMCG_SWAP
|
|
/**
|
|
* mem_cgroup_move_swap_account - move swap charge and swap_cgroup's record.
|
|
* @entry: swap entry to be moved
|
|
* @from: mem_cgroup which the entry is moved from
|
|
* @to: mem_cgroup which the entry is moved to
|
|
*
|
|
* It succeeds only when the swap_cgroup's record for this entry is the same
|
|
* as the mem_cgroup's id of @from.
|
|
*
|
|
* Returns 0 on success, -EINVAL on failure.
|
|
*
|
|
* The caller must have charged to @to, IOW, called page_counter_charge() about
|
|
* both res and memsw, and called css_get().
|
|
*/
|
|
static int mem_cgroup_move_swap_account(swp_entry_t entry,
|
|
struct mem_cgroup *from, struct mem_cgroup *to)
|
|
{
|
|
unsigned short old_id, new_id;
|
|
|
|
old_id = mem_cgroup_id(from);
|
|
new_id = mem_cgroup_id(to);
|
|
|
|
if (swap_cgroup_cmpxchg(entry, old_id, new_id) == old_id) {
|
|
mod_memcg_state(from, MEMCG_SWAP, -1);
|
|
mod_memcg_state(to, MEMCG_SWAP, 1);
|
|
return 0;
|
|
}
|
|
return -EINVAL;
|
|
}
|
|
#else
|
|
static inline int mem_cgroup_move_swap_account(swp_entry_t entry,
|
|
struct mem_cgroup *from, struct mem_cgroup *to)
|
|
{
|
|
return -EINVAL;
|
|
}
|
|
#endif
|
|
|
|
static DEFINE_MUTEX(memcg_max_mutex);
|
|
|
|
static int mem_cgroup_resize_max(struct mem_cgroup *memcg,
|
|
unsigned long max, bool memsw)
|
|
{
|
|
bool enlarge = false;
|
|
bool drained = false;
|
|
int ret;
|
|
bool limits_invariant;
|
|
struct page_counter *counter = memsw ? &memcg->memsw : &memcg->memory;
|
|
|
|
do {
|
|
if (signal_pending(current)) {
|
|
ret = -EINTR;
|
|
break;
|
|
}
|
|
|
|
mutex_lock(&memcg_max_mutex);
|
|
/*
|
|
* Make sure that the new limit (memsw or memory limit) doesn't
|
|
* break our basic invariant rule memory.max <= memsw.max.
|
|
*/
|
|
limits_invariant = memsw ? max >= memcg->memory.max :
|
|
max <= memcg->memsw.max;
|
|
if (!limits_invariant) {
|
|
mutex_unlock(&memcg_max_mutex);
|
|
ret = -EINVAL;
|
|
break;
|
|
}
|
|
if (max > counter->max)
|
|
enlarge = true;
|
|
ret = page_counter_set_max(counter, max);
|
|
mutex_unlock(&memcg_max_mutex);
|
|
|
|
if (!ret)
|
|
break;
|
|
|
|
if (!drained) {
|
|
drain_all_stock(memcg);
|
|
drained = true;
|
|
continue;
|
|
}
|
|
|
|
if (!try_to_free_mem_cgroup_pages(memcg, 1,
|
|
GFP_KERNEL, !memsw)) {
|
|
ret = -EBUSY;
|
|
break;
|
|
}
|
|
} while (true);
|
|
|
|
if (!ret && enlarge)
|
|
memcg_oom_recover(memcg);
|
|
|
|
return ret;
|
|
}
|
|
|
|
unsigned long mem_cgroup_soft_limit_reclaim(pg_data_t *pgdat, int order,
|
|
gfp_t gfp_mask,
|
|
unsigned long *total_scanned)
|
|
{
|
|
unsigned long nr_reclaimed = 0;
|
|
struct mem_cgroup_per_node *mz, *next_mz = NULL;
|
|
unsigned long reclaimed;
|
|
int loop = 0;
|
|
struct mem_cgroup_tree_per_node *mctz;
|
|
unsigned long excess;
|
|
unsigned long nr_scanned;
|
|
|
|
if (order > 0)
|
|
return 0;
|
|
|
|
mctz = soft_limit_tree_node(pgdat->node_id);
|
|
|
|
/*
|
|
* Do not even bother to check the largest node if the root
|
|
* is empty. Do it lockless to prevent lock bouncing. Races
|
|
* are acceptable as soft limit is best effort anyway.
|
|
*/
|
|
if (!mctz || RB_EMPTY_ROOT(&mctz->rb_root))
|
|
return 0;
|
|
|
|
/*
|
|
* This loop can run a while, specially if mem_cgroup's continuously
|
|
* keep exceeding their soft limit and putting the system under
|
|
* pressure
|
|
*/
|
|
do {
|
|
if (next_mz)
|
|
mz = next_mz;
|
|
else
|
|
mz = mem_cgroup_largest_soft_limit_node(mctz);
|
|
if (!mz)
|
|
break;
|
|
|
|
nr_scanned = 0;
|
|
reclaimed = mem_cgroup_soft_reclaim(mz->memcg, pgdat,
|
|
gfp_mask, &nr_scanned);
|
|
nr_reclaimed += reclaimed;
|
|
*total_scanned += nr_scanned;
|
|
spin_lock_irq(&mctz->lock);
|
|
__mem_cgroup_remove_exceeded(mz, mctz);
|
|
|
|
/*
|
|
* If we failed to reclaim anything from this memory cgroup
|
|
* it is time to move on to the next cgroup
|
|
*/
|
|
next_mz = NULL;
|
|
if (!reclaimed)
|
|
next_mz = __mem_cgroup_largest_soft_limit_node(mctz);
|
|
|
|
excess = soft_limit_excess(mz->memcg);
|
|
/*
|
|
* One school of thought says that we should not add
|
|
* back the node to the tree if reclaim returns 0.
|
|
* But our reclaim could return 0, simply because due
|
|
* to priority we are exposing a smaller subset of
|
|
* memory to reclaim from. Consider this as a longer
|
|
* term TODO.
|
|
*/
|
|
/* If excess == 0, no tree ops */
|
|
__mem_cgroup_insert_exceeded(mz, mctz, excess);
|
|
spin_unlock_irq(&mctz->lock);
|
|
css_put(&mz->memcg->css);
|
|
loop++;
|
|
/*
|
|
* Could not reclaim anything and there are no more
|
|
* mem cgroups to try or we seem to be looping without
|
|
* reclaiming anything.
|
|
*/
|
|
if (!nr_reclaimed &&
|
|
(next_mz == NULL ||
|
|
loop > MEM_CGROUP_MAX_SOFT_LIMIT_RECLAIM_LOOPS))
|
|
break;
|
|
} while (!nr_reclaimed);
|
|
if (next_mz)
|
|
css_put(&next_mz->memcg->css);
|
|
return nr_reclaimed;
|
|
}
|
|
|
|
/*
|
|
* Test whether @memcg has children, dead or alive. Note that this
|
|
* function doesn't care whether @memcg has use_hierarchy enabled and
|
|
* returns %true if there are child csses according to the cgroup
|
|
* hierarchy. Testing use_hierarchy is the caller's responsiblity.
|
|
*/
|
|
static inline bool memcg_has_children(struct mem_cgroup *memcg)
|
|
{
|
|
bool ret;
|
|
|
|
rcu_read_lock();
|
|
ret = css_next_child(NULL, &memcg->css);
|
|
rcu_read_unlock();
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Reclaims as many pages from the given memcg as possible.
|
|
*
|
|
* Caller is responsible for holding css reference for memcg.
|
|
*/
|
|
static int mem_cgroup_force_empty(struct mem_cgroup *memcg)
|
|
{
|
|
int nr_retries = MEM_CGROUP_RECLAIM_RETRIES;
|
|
|
|
/* we call try-to-free pages for make this cgroup empty */
|
|
lru_add_drain_all();
|
|
|
|
drain_all_stock(memcg);
|
|
|
|
/* try to free all pages in this cgroup */
|
|
while (nr_retries && page_counter_read(&memcg->memory)) {
|
|
int progress;
|
|
|
|
if (signal_pending(current))
|
|
return -EINTR;
|
|
|
|
progress = try_to_free_mem_cgroup_pages(memcg, 1,
|
|
GFP_KERNEL, true);
|
|
if (!progress) {
|
|
nr_retries--;
|
|
/* maybe some writeback is necessary */
|
|
congestion_wait(BLK_RW_ASYNC, HZ/10);
|
|
}
|
|
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static ssize_t mem_cgroup_force_empty_write(struct kernfs_open_file *of,
|
|
char *buf, size_t nbytes,
|
|
loff_t off)
|
|
{
|
|
struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of));
|
|
|
|
if (mem_cgroup_is_root(memcg))
|
|
return -EINVAL;
|
|
return mem_cgroup_force_empty(memcg) ?: nbytes;
|
|
}
|
|
|
|
static u64 mem_cgroup_hierarchy_read(struct cgroup_subsys_state *css,
|
|
struct cftype *cft)
|
|
{
|
|
return mem_cgroup_from_css(css)->use_hierarchy;
|
|
}
|
|
|
|
static int mem_cgroup_hierarchy_write(struct cgroup_subsys_state *css,
|
|
struct cftype *cft, u64 val)
|
|
{
|
|
int retval = 0;
|
|
struct mem_cgroup *memcg = mem_cgroup_from_css(css);
|
|
struct mem_cgroup *parent_memcg = mem_cgroup_from_css(memcg->css.parent);
|
|
|
|
if (memcg->use_hierarchy == val)
|
|
return 0;
|
|
|
|
/*
|
|
* If parent's use_hierarchy is set, we can't make any modifications
|
|
* in the child subtrees. If it is unset, then the change can
|
|
* occur, provided the current cgroup has no children.
|
|
*
|
|
* For the root cgroup, parent_mem is NULL, we allow value to be
|
|
* set if there are no children.
|
|
*/
|
|
if ((!parent_memcg || !parent_memcg->use_hierarchy) &&
|
|
(val == 1 || val == 0)) {
|
|
if (!memcg_has_children(memcg))
|
|
memcg->use_hierarchy = val;
|
|
else
|
|
retval = -EBUSY;
|
|
} else
|
|
retval = -EINVAL;
|
|
|
|
return retval;
|
|
}
|
|
|
|
static unsigned long mem_cgroup_usage(struct mem_cgroup *memcg, bool swap)
|
|
{
|
|
unsigned long val;
|
|
|
|
if (mem_cgroup_is_root(memcg)) {
|
|
val = memcg_page_state(memcg, MEMCG_CACHE) +
|
|
memcg_page_state(memcg, MEMCG_RSS);
|
|
if (swap)
|
|
val += memcg_page_state(memcg, MEMCG_SWAP);
|
|
} else {
|
|
if (!swap)
|
|
val = page_counter_read(&memcg->memory);
|
|
else
|
|
val = page_counter_read(&memcg->memsw);
|
|
}
|
|
return val;
|
|
}
|
|
|
|
enum {
|
|
RES_USAGE,
|
|
RES_LIMIT,
|
|
RES_MAX_USAGE,
|
|
RES_FAILCNT,
|
|
RES_SOFT_LIMIT,
|
|
};
|
|
|
|
static u64 mem_cgroup_read_u64(struct cgroup_subsys_state *css,
|
|
struct cftype *cft)
|
|
{
|
|
struct mem_cgroup *memcg = mem_cgroup_from_css(css);
|
|
struct page_counter *counter;
|
|
|
|
switch (MEMFILE_TYPE(cft->private)) {
|
|
case _MEM:
|
|
counter = &memcg->memory;
|
|
break;
|
|
case _MEMSWAP:
|
|
counter = &memcg->memsw;
|
|
break;
|
|
case _KMEM:
|
|
counter = &memcg->kmem;
|
|
break;
|
|
case _TCP:
|
|
counter = &memcg->tcpmem;
|
|
break;
|
|
default:
|
|
BUG();
|
|
}
|
|
|
|
switch (MEMFILE_ATTR(cft->private)) {
|
|
case RES_USAGE:
|
|
if (counter == &memcg->memory)
|
|
return (u64)mem_cgroup_usage(memcg, false) * PAGE_SIZE;
|
|
if (counter == &memcg->memsw)
|
|
return (u64)mem_cgroup_usage(memcg, true) * PAGE_SIZE;
|
|
return (u64)page_counter_read(counter) * PAGE_SIZE;
|
|
case RES_LIMIT:
|
|
return (u64)counter->max * PAGE_SIZE;
|
|
case RES_MAX_USAGE:
|
|
return (u64)counter->watermark * PAGE_SIZE;
|
|
case RES_FAILCNT:
|
|
return counter->failcnt;
|
|
case RES_SOFT_LIMIT:
|
|
return (u64)memcg->soft_limit * PAGE_SIZE;
|
|
default:
|
|
BUG();
|
|
}
|
|
}
|
|
|
|
static void memcg_flush_percpu_vmstats(struct mem_cgroup *memcg, bool slab_only)
|
|
{
|
|
unsigned long stat[MEMCG_NR_STAT];
|
|
struct mem_cgroup *mi;
|
|
int node, cpu, i;
|
|
int min_idx, max_idx;
|
|
|
|
if (slab_only) {
|
|
min_idx = NR_SLAB_RECLAIMABLE;
|
|
max_idx = NR_SLAB_UNRECLAIMABLE;
|
|
} else {
|
|
min_idx = 0;
|
|
max_idx = MEMCG_NR_STAT;
|
|
}
|
|
|
|
for (i = min_idx; i < max_idx; i++)
|
|
stat[i] = 0;
|
|
|
|
for_each_online_cpu(cpu)
|
|
for (i = min_idx; i < max_idx; i++)
|
|
stat[i] += per_cpu(memcg->vmstats_percpu->stat[i], cpu);
|
|
|
|
for (mi = memcg; mi; mi = parent_mem_cgroup(mi))
|
|
for (i = min_idx; i < max_idx; i++)
|
|
atomic_long_add(stat[i], &mi->vmstats[i]);
|
|
|
|
if (!slab_only)
|
|
max_idx = NR_VM_NODE_STAT_ITEMS;
|
|
|
|
for_each_node(node) {
|
|
struct mem_cgroup_per_node *pn = memcg->nodeinfo[node];
|
|
struct mem_cgroup_per_node *pi;
|
|
|
|
for (i = min_idx; i < max_idx; i++)
|
|
stat[i] = 0;
|
|
|
|
for_each_online_cpu(cpu)
|
|
for (i = min_idx; i < max_idx; i++)
|
|
stat[i] += per_cpu(
|
|
pn->lruvec_stat_cpu->count[i], cpu);
|
|
|
|
for (pi = pn; pi; pi = parent_nodeinfo(pi, node))
|
|
for (i = min_idx; i < max_idx; i++)
|
|
atomic_long_add(stat[i], &pi->lruvec_stat[i]);
|
|
}
|
|
}
|
|
|
|
static void memcg_flush_percpu_vmevents(struct mem_cgroup *memcg)
|
|
{
|
|
unsigned long events[NR_VM_EVENT_ITEMS];
|
|
struct mem_cgroup *mi;
|
|
int cpu, i;
|
|
|
|
for (i = 0; i < NR_VM_EVENT_ITEMS; i++)
|
|
events[i] = 0;
|
|
|
|
for_each_online_cpu(cpu)
|
|
for (i = 0; i < NR_VM_EVENT_ITEMS; i++)
|
|
events[i] += per_cpu(memcg->vmstats_percpu->events[i],
|
|
cpu);
|
|
|
|
for (mi = memcg; mi; mi = parent_mem_cgroup(mi))
|
|
for (i = 0; i < NR_VM_EVENT_ITEMS; i++)
|
|
atomic_long_add(events[i], &mi->vmevents[i]);
|
|
}
|
|
|
|
#ifdef CONFIG_MEMCG_KMEM
|
|
static int memcg_online_kmem(struct mem_cgroup *memcg)
|
|
{
|
|
int memcg_id;
|
|
|
|
if (cgroup_memory_nokmem)
|
|
return 0;
|
|
|
|
BUG_ON(memcg->kmemcg_id >= 0);
|
|
BUG_ON(memcg->kmem_state);
|
|
|
|
memcg_id = memcg_alloc_cache_id();
|
|
if (memcg_id < 0)
|
|
return memcg_id;
|
|
|
|
static_branch_inc(&memcg_kmem_enabled_key);
|
|
/*
|
|
* A memory cgroup is considered kmem-online as soon as it gets
|
|
* kmemcg_id. Setting the id after enabling static branching will
|
|
* guarantee no one starts accounting before all call sites are
|
|
* patched.
|
|
*/
|
|
memcg->kmemcg_id = memcg_id;
|
|
memcg->kmem_state = KMEM_ONLINE;
|
|
INIT_LIST_HEAD(&memcg->kmem_caches);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void memcg_offline_kmem(struct mem_cgroup *memcg)
|
|
{
|
|
struct cgroup_subsys_state *css;
|
|
struct mem_cgroup *parent, *child;
|
|
int kmemcg_id;
|
|
|
|
if (memcg->kmem_state != KMEM_ONLINE)
|
|
return;
|
|
/*
|
|
* Clear the online state before clearing memcg_caches array
|
|
* entries. The slab_mutex in memcg_deactivate_kmem_caches()
|
|
* guarantees that no cache will be created for this cgroup
|
|
* after we are done (see memcg_create_kmem_cache()).
|
|
*/
|
|
memcg->kmem_state = KMEM_ALLOCATED;
|
|
|
|
parent = parent_mem_cgroup(memcg);
|
|
if (!parent)
|
|
parent = root_mem_cgroup;
|
|
|
|
/*
|
|
* Deactivate and reparent kmem_caches. Then flush percpu
|
|
* slab statistics to have precise values at the parent and
|
|
* all ancestor levels. It's required to keep slab stats
|
|
* accurate after the reparenting of kmem_caches.
|
|
*/
|
|
memcg_deactivate_kmem_caches(memcg, parent);
|
|
memcg_flush_percpu_vmstats(memcg, true);
|
|
|
|
kmemcg_id = memcg->kmemcg_id;
|
|
BUG_ON(kmemcg_id < 0);
|
|
|
|
/*
|
|
* Change kmemcg_id of this cgroup and all its descendants to the
|
|
* parent's id, and then move all entries from this cgroup's list_lrus
|
|
* to ones of the parent. After we have finished, all list_lrus
|
|
* corresponding to this cgroup are guaranteed to remain empty. The
|
|
* ordering is imposed by list_lru_node->lock taken by
|
|
* memcg_drain_all_list_lrus().
|
|
*/
|
|
rcu_read_lock(); /* can be called from css_free w/o cgroup_mutex */
|
|
css_for_each_descendant_pre(css, &memcg->css) {
|
|
child = mem_cgroup_from_css(css);
|
|
BUG_ON(child->kmemcg_id != kmemcg_id);
|
|
child->kmemcg_id = parent->kmemcg_id;
|
|
if (!memcg->use_hierarchy)
|
|
break;
|
|
}
|
|
rcu_read_unlock();
|
|
|
|
memcg_drain_all_list_lrus(kmemcg_id, parent);
|
|
|
|
memcg_free_cache_id(kmemcg_id);
|
|
}
|
|
|
|
static void memcg_free_kmem(struct mem_cgroup *memcg)
|
|
{
|
|
/* css_alloc() failed, offlining didn't happen */
|
|
if (unlikely(memcg->kmem_state == KMEM_ONLINE))
|
|
memcg_offline_kmem(memcg);
|
|
|
|
if (memcg->kmem_state == KMEM_ALLOCATED) {
|
|
WARN_ON(!list_empty(&memcg->kmem_caches));
|
|
static_branch_dec(&memcg_kmem_enabled_key);
|
|
}
|
|
}
|
|
#else
|
|
static int memcg_online_kmem(struct mem_cgroup *memcg)
|
|
{
|
|
return 0;
|
|
}
|
|
static void memcg_offline_kmem(struct mem_cgroup *memcg)
|
|
{
|
|
}
|
|
static void memcg_free_kmem(struct mem_cgroup *memcg)
|
|
{
|
|
}
|
|
#endif /* CONFIG_MEMCG_KMEM */
|
|
|
|
static int memcg_update_kmem_max(struct mem_cgroup *memcg,
|
|
unsigned long max)
|
|
{
|
|
int ret;
|
|
|
|
mutex_lock(&memcg_max_mutex);
|
|
ret = page_counter_set_max(&memcg->kmem, max);
|
|
mutex_unlock(&memcg_max_mutex);
|
|
return ret;
|
|
}
|
|
|
|
static int memcg_update_tcp_max(struct mem_cgroup *memcg, unsigned long max)
|
|
{
|
|
int ret;
|
|
|
|
mutex_lock(&memcg_max_mutex);
|
|
|
|
ret = page_counter_set_max(&memcg->tcpmem, max);
|
|
if (ret)
|
|
goto out;
|
|
|
|
if (!memcg->tcpmem_active) {
|
|
/*
|
|
* The active flag needs to be written after the static_key
|
|
* update. This is what guarantees that the socket activation
|
|
* function is the last one to run. See mem_cgroup_sk_alloc()
|
|
* for details, and note that we don't mark any socket as
|
|
* belonging to this memcg until that flag is up.
|
|
*
|
|
* We need to do this, because static_keys will span multiple
|
|
* sites, but we can't control their order. If we mark a socket
|
|
* as accounted, but the accounting functions are not patched in
|
|
* yet, we'll lose accounting.
|
|
*
|
|
* We never race with the readers in mem_cgroup_sk_alloc(),
|
|
* because when this value change, the code to process it is not
|
|
* patched in yet.
|
|
*/
|
|
static_branch_inc(&memcg_sockets_enabled_key);
|
|
memcg->tcpmem_active = true;
|
|
}
|
|
out:
|
|
mutex_unlock(&memcg_max_mutex);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* The user of this function is...
|
|
* RES_LIMIT.
|
|
*/
|
|
static ssize_t mem_cgroup_write(struct kernfs_open_file *of,
|
|
char *buf, size_t nbytes, loff_t off)
|
|
{
|
|
struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of));
|
|
unsigned long nr_pages;
|
|
int ret;
|
|
|
|
buf = strstrip(buf);
|
|
ret = page_counter_memparse(buf, "-1", &nr_pages);
|
|
if (ret)
|
|
return ret;
|
|
|
|
switch (MEMFILE_ATTR(of_cft(of)->private)) {
|
|
case RES_LIMIT:
|
|
if (mem_cgroup_is_root(memcg)) { /* Can't set limit on root */
|
|
ret = -EINVAL;
|
|
break;
|
|
}
|
|
switch (MEMFILE_TYPE(of_cft(of)->private)) {
|
|
case _MEM:
|
|
ret = mem_cgroup_resize_max(memcg, nr_pages, false);
|
|
break;
|
|
case _MEMSWAP:
|
|
ret = mem_cgroup_resize_max(memcg, nr_pages, true);
|
|
break;
|
|
case _KMEM:
|
|
pr_warn_once("kmem.limit_in_bytes is deprecated and will be removed. "
|
|
"Please report your usecase to linux-mm@kvack.org if you "
|
|
"depend on this functionality.\n");
|
|
ret = memcg_update_kmem_max(memcg, nr_pages);
|
|
break;
|
|
case _TCP:
|
|
ret = memcg_update_tcp_max(memcg, nr_pages);
|
|
break;
|
|
}
|
|
break;
|
|
case RES_SOFT_LIMIT:
|
|
memcg->soft_limit = nr_pages;
|
|
ret = 0;
|
|
break;
|
|
}
|
|
return ret ?: nbytes;
|
|
}
|
|
|
|
static ssize_t mem_cgroup_reset(struct kernfs_open_file *of, char *buf,
|
|
size_t nbytes, loff_t off)
|
|
{
|
|
struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of));
|
|
struct page_counter *counter;
|
|
|
|
switch (MEMFILE_TYPE(of_cft(of)->private)) {
|
|
case _MEM:
|
|
counter = &memcg->memory;
|
|
break;
|
|
case _MEMSWAP:
|
|
counter = &memcg->memsw;
|
|
break;
|
|
case _KMEM:
|
|
counter = &memcg->kmem;
|
|
break;
|
|
case _TCP:
|
|
counter = &memcg->tcpmem;
|
|
break;
|
|
default:
|
|
BUG();
|
|
}
|
|
|
|
switch (MEMFILE_ATTR(of_cft(of)->private)) {
|
|
case RES_MAX_USAGE:
|
|
page_counter_reset_watermark(counter);
|
|
break;
|
|
case RES_FAILCNT:
|
|
counter->failcnt = 0;
|
|
break;
|
|
default:
|
|
BUG();
|
|
}
|
|
|
|
return nbytes;
|
|
}
|
|
|
|
static u64 mem_cgroup_move_charge_read(struct cgroup_subsys_state *css,
|
|
struct cftype *cft)
|
|
{
|
|
return mem_cgroup_from_css(css)->move_charge_at_immigrate;
|
|
}
|
|
|
|
#ifdef CONFIG_MMU
|
|
static int mem_cgroup_move_charge_write(struct cgroup_subsys_state *css,
|
|
struct cftype *cft, u64 val)
|
|
{
|
|
struct mem_cgroup *memcg = mem_cgroup_from_css(css);
|
|
|
|
if (val & ~MOVE_MASK)
|
|
return -EINVAL;
|
|
|
|
/*
|
|
* No kind of locking is needed in here, because ->can_attach() will
|
|
* check this value once in the beginning of the process, and then carry
|
|
* on with stale data. This means that changes to this value will only
|
|
* affect task migrations starting after the change.
|
|
*/
|
|
memcg->move_charge_at_immigrate = val;
|
|
return 0;
|
|
}
|
|
#else
|
|
static int mem_cgroup_move_charge_write(struct cgroup_subsys_state *css,
|
|
struct cftype *cft, u64 val)
|
|
{
|
|
return -ENOSYS;
|
|
}
|
|
#endif
|
|
|
|
#ifdef CONFIG_NUMA
|
|
|
|
#define LRU_ALL_FILE (BIT(LRU_INACTIVE_FILE) | BIT(LRU_ACTIVE_FILE))
|
|
#define LRU_ALL_ANON (BIT(LRU_INACTIVE_ANON) | BIT(LRU_ACTIVE_ANON))
|
|
#define LRU_ALL ((1 << NR_LRU_LISTS) - 1)
|
|
|
|
static unsigned long mem_cgroup_node_nr_lru_pages(struct mem_cgroup *memcg,
|
|
int nid, unsigned int lru_mask)
|
|
{
|
|
struct lruvec *lruvec = mem_cgroup_lruvec(NODE_DATA(nid), memcg);
|
|
unsigned long nr = 0;
|
|
enum lru_list lru;
|
|
|
|
VM_BUG_ON((unsigned)nid >= nr_node_ids);
|
|
|
|
for_each_lru(lru) {
|
|
if (!(BIT(lru) & lru_mask))
|
|
continue;
|
|
nr += lruvec_page_state_local(lruvec, NR_LRU_BASE + lru);
|
|
}
|
|
return nr;
|
|
}
|
|
|
|
static unsigned long mem_cgroup_nr_lru_pages(struct mem_cgroup *memcg,
|
|
unsigned int lru_mask)
|
|
{
|
|
unsigned long nr = 0;
|
|
enum lru_list lru;
|
|
|
|
for_each_lru(lru) {
|
|
if (!(BIT(lru) & lru_mask))
|
|
continue;
|
|
nr += memcg_page_state_local(memcg, NR_LRU_BASE + lru);
|
|
}
|
|
return nr;
|
|
}
|
|
|
|
static int memcg_numa_stat_show(struct seq_file *m, void *v)
|
|
{
|
|
struct numa_stat {
|
|
const char *name;
|
|
unsigned int lru_mask;
|
|
};
|
|
|
|
static const struct numa_stat stats[] = {
|
|
{ "total", LRU_ALL },
|
|
{ "file", LRU_ALL_FILE },
|
|
{ "anon", LRU_ALL_ANON },
|
|
{ "unevictable", BIT(LRU_UNEVICTABLE) },
|
|
};
|
|
const struct numa_stat *stat;
|
|
int nid;
|
|
unsigned long nr;
|
|
struct mem_cgroup *memcg = mem_cgroup_from_seq(m);
|
|
|
|
for (stat = stats; stat < stats + ARRAY_SIZE(stats); stat++) {
|
|
nr = mem_cgroup_nr_lru_pages(memcg, stat->lru_mask);
|
|
seq_printf(m, "%s=%lu", stat->name, nr);
|
|
for_each_node_state(nid, N_MEMORY) {
|
|
nr = mem_cgroup_node_nr_lru_pages(memcg, nid,
|
|
stat->lru_mask);
|
|
seq_printf(m, " N%d=%lu", nid, nr);
|
|
}
|
|
seq_putc(m, '\n');
|
|
}
|
|
|
|
for (stat = stats; stat < stats + ARRAY_SIZE(stats); stat++) {
|
|
struct mem_cgroup *iter;
|
|
|
|
nr = 0;
|
|
for_each_mem_cgroup_tree(iter, memcg)
|
|
nr += mem_cgroup_nr_lru_pages(iter, stat->lru_mask);
|
|
seq_printf(m, "hierarchical_%s=%lu", stat->name, nr);
|
|
for_each_node_state(nid, N_MEMORY) {
|
|
nr = 0;
|
|
for_each_mem_cgroup_tree(iter, memcg)
|
|
nr += mem_cgroup_node_nr_lru_pages(
|
|
iter, nid, stat->lru_mask);
|
|
seq_printf(m, " N%d=%lu", nid, nr);
|
|
}
|
|
seq_putc(m, '\n');
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
#endif /* CONFIG_NUMA */
|
|
|
|
static const unsigned int memcg1_stats[] = {
|
|
MEMCG_CACHE,
|
|
MEMCG_RSS,
|
|
MEMCG_RSS_HUGE,
|
|
NR_SHMEM,
|
|
NR_FILE_MAPPED,
|
|
NR_FILE_DIRTY,
|
|
NR_WRITEBACK,
|
|
MEMCG_SWAP,
|
|
};
|
|
|
|
static const char *const memcg1_stat_names[] = {
|
|
"cache",
|
|
"rss",
|
|
"rss_huge",
|
|
"shmem",
|
|
"mapped_file",
|
|
"dirty",
|
|
"writeback",
|
|
"swap",
|
|
};
|
|
|
|
/* Universal VM events cgroup1 shows, original sort order */
|
|
static const unsigned int memcg1_events[] = {
|
|
PGPGIN,
|
|
PGPGOUT,
|
|
PGFAULT,
|
|
PGMAJFAULT,
|
|
};
|
|
|
|
static const char *const memcg1_event_names[] = {
|
|
"pgpgin",
|
|
"pgpgout",
|
|
"pgfault",
|
|
"pgmajfault",
|
|
};
|
|
|
|
static int memcg_stat_show(struct seq_file *m, void *v)
|
|
{
|
|
struct mem_cgroup *memcg = mem_cgroup_from_seq(m);
|
|
unsigned long memory, memsw;
|
|
struct mem_cgroup *mi;
|
|
unsigned int i;
|
|
|
|
BUILD_BUG_ON(ARRAY_SIZE(memcg1_stat_names) != ARRAY_SIZE(memcg1_stats));
|
|
BUILD_BUG_ON(ARRAY_SIZE(mem_cgroup_lru_names) != NR_LRU_LISTS);
|
|
|
|
for (i = 0; i < ARRAY_SIZE(memcg1_stats); i++) {
|
|
if (memcg1_stats[i] == MEMCG_SWAP && !do_memsw_account())
|
|
continue;
|
|
seq_printf(m, "%s %lu\n", memcg1_stat_names[i],
|
|
memcg_page_state_local(memcg, memcg1_stats[i]) *
|
|
PAGE_SIZE);
|
|
}
|
|
|
|
for (i = 0; i < ARRAY_SIZE(memcg1_events); i++)
|
|
seq_printf(m, "%s %lu\n", memcg1_event_names[i],
|
|
memcg_events_local(memcg, memcg1_events[i]));
|
|
|
|
for (i = 0; i < NR_LRU_LISTS; i++)
|
|
seq_printf(m, "%s %lu\n", mem_cgroup_lru_names[i],
|
|
memcg_page_state_local(memcg, NR_LRU_BASE + i) *
|
|
PAGE_SIZE);
|
|
|
|
/* Hierarchical information */
|
|
memory = memsw = PAGE_COUNTER_MAX;
|
|
for (mi = memcg; mi; mi = parent_mem_cgroup(mi)) {
|
|
memory = min(memory, mi->memory.max);
|
|
memsw = min(memsw, mi->memsw.max);
|
|
}
|
|
seq_printf(m, "hierarchical_memory_limit %llu\n",
|
|
(u64)memory * PAGE_SIZE);
|
|
if (do_memsw_account())
|
|
seq_printf(m, "hierarchical_memsw_limit %llu\n",
|
|
(u64)memsw * PAGE_SIZE);
|
|
|
|
for (i = 0; i < ARRAY_SIZE(memcg1_stats); i++) {
|
|
if (memcg1_stats[i] == MEMCG_SWAP && !do_memsw_account())
|
|
continue;
|
|
seq_printf(m, "total_%s %llu\n", memcg1_stat_names[i],
|
|
(u64)memcg_page_state(memcg, memcg1_stats[i]) *
|
|
PAGE_SIZE);
|
|
}
|
|
|
|
for (i = 0; i < ARRAY_SIZE(memcg1_events); i++)
|
|
seq_printf(m, "total_%s %llu\n", memcg1_event_names[i],
|
|
(u64)memcg_events(memcg, memcg1_events[i]));
|
|
|
|
for (i = 0; i < NR_LRU_LISTS; i++)
|
|
seq_printf(m, "total_%s %llu\n", mem_cgroup_lru_names[i],
|
|
(u64)memcg_page_state(memcg, NR_LRU_BASE + i) *
|
|
PAGE_SIZE);
|
|
|
|
#ifdef CONFIG_DEBUG_VM
|
|
{
|
|
pg_data_t *pgdat;
|
|
struct mem_cgroup_per_node *mz;
|
|
struct zone_reclaim_stat *rstat;
|
|
unsigned long recent_rotated[2] = {0, 0};
|
|
unsigned long recent_scanned[2] = {0, 0};
|
|
|
|
for_each_online_pgdat(pgdat) {
|
|
mz = mem_cgroup_nodeinfo(memcg, pgdat->node_id);
|
|
rstat = &mz->lruvec.reclaim_stat;
|
|
|
|
recent_rotated[0] += rstat->recent_rotated[0];
|
|
recent_rotated[1] += rstat->recent_rotated[1];
|
|
recent_scanned[0] += rstat->recent_scanned[0];
|
|
recent_scanned[1] += rstat->recent_scanned[1];
|
|
}
|
|
seq_printf(m, "recent_rotated_anon %lu\n", recent_rotated[0]);
|
|
seq_printf(m, "recent_rotated_file %lu\n", recent_rotated[1]);
|
|
seq_printf(m, "recent_scanned_anon %lu\n", recent_scanned[0]);
|
|
seq_printf(m, "recent_scanned_file %lu\n", recent_scanned[1]);
|
|
}
|
|
#endif
|
|
|
|
return 0;
|
|
}
|
|
|
|
static u64 mem_cgroup_swappiness_read(struct cgroup_subsys_state *css,
|
|
struct cftype *cft)
|
|
{
|
|
struct mem_cgroup *memcg = mem_cgroup_from_css(css);
|
|
|
|
return mem_cgroup_swappiness(memcg);
|
|
}
|
|
|
|
static int mem_cgroup_swappiness_write(struct cgroup_subsys_state *css,
|
|
struct cftype *cft, u64 val)
|
|
{
|
|
struct mem_cgroup *memcg = mem_cgroup_from_css(css);
|
|
|
|
if (val > 100)
|
|
return -EINVAL;
|
|
|
|
if (css->parent)
|
|
memcg->swappiness = val;
|
|
else
|
|
vm_swappiness = val;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void __mem_cgroup_threshold(struct mem_cgroup *memcg, bool swap)
|
|
{
|
|
struct mem_cgroup_threshold_ary *t;
|
|
unsigned long usage;
|
|
int i;
|
|
|
|
rcu_read_lock();
|
|
if (!swap)
|
|
t = rcu_dereference(memcg->thresholds.primary);
|
|
else
|
|
t = rcu_dereference(memcg->memsw_thresholds.primary);
|
|
|
|
if (!t)
|
|
goto unlock;
|
|
|
|
usage = mem_cgroup_usage(memcg, swap);
|
|
|
|
/*
|
|
* current_threshold points to threshold just below or equal to usage.
|
|
* If it's not true, a threshold was crossed after last
|
|
* call of __mem_cgroup_threshold().
|
|
*/
|
|
i = t->current_threshold;
|
|
|
|
/*
|
|
* Iterate backward over array of thresholds starting from
|
|
* current_threshold and check if a threshold is crossed.
|
|
* If none of thresholds below usage is crossed, we read
|
|
* only one element of the array here.
|
|
*/
|
|
for (; i >= 0 && unlikely(t->entries[i].threshold > usage); i--)
|
|
eventfd_signal(t->entries[i].eventfd, 1);
|
|
|
|
/* i = current_threshold + 1 */
|
|
i++;
|
|
|
|
/*
|
|
* Iterate forward over array of thresholds starting from
|
|
* current_threshold+1 and check if a threshold is crossed.
|
|
* If none of thresholds above usage is crossed, we read
|
|
* only one element of the array here.
|
|
*/
|
|
for (; i < t->size && unlikely(t->entries[i].threshold <= usage); i++)
|
|
eventfd_signal(t->entries[i].eventfd, 1);
|
|
|
|
/* Update current_threshold */
|
|
t->current_threshold = i - 1;
|
|
unlock:
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
static void mem_cgroup_threshold(struct mem_cgroup *memcg)
|
|
{
|
|
while (memcg) {
|
|
__mem_cgroup_threshold(memcg, false);
|
|
if (do_memsw_account())
|
|
__mem_cgroup_threshold(memcg, true);
|
|
|
|
memcg = parent_mem_cgroup(memcg);
|
|
}
|
|
}
|
|
|
|
static int compare_thresholds(const void *a, const void *b)
|
|
{
|
|
const struct mem_cgroup_threshold *_a = a;
|
|
const struct mem_cgroup_threshold *_b = b;
|
|
|
|
if (_a->threshold > _b->threshold)
|
|
return 1;
|
|
|
|
if (_a->threshold < _b->threshold)
|
|
return -1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int mem_cgroup_oom_notify_cb(struct mem_cgroup *memcg)
|
|
{
|
|
struct mem_cgroup_eventfd_list *ev;
|
|
|
|
spin_lock(&memcg_oom_lock);
|
|
|
|
list_for_each_entry(ev, &memcg->oom_notify, list)
|
|
eventfd_signal(ev->eventfd, 1);
|
|
|
|
spin_unlock(&memcg_oom_lock);
|
|
return 0;
|
|
}
|
|
|
|
static void mem_cgroup_oom_notify(struct mem_cgroup *memcg)
|
|
{
|
|
struct mem_cgroup *iter;
|
|
|
|
for_each_mem_cgroup_tree(iter, memcg)
|
|
mem_cgroup_oom_notify_cb(iter);
|
|
}
|
|
|
|
static int __mem_cgroup_usage_register_event(struct mem_cgroup *memcg,
|
|
struct eventfd_ctx *eventfd, const char *args, enum res_type type)
|
|
{
|
|
struct mem_cgroup_thresholds *thresholds;
|
|
struct mem_cgroup_threshold_ary *new;
|
|
unsigned long threshold;
|
|
unsigned long usage;
|
|
int i, size, ret;
|
|
|
|
ret = page_counter_memparse(args, "-1", &threshold);
|
|
if (ret)
|
|
return ret;
|
|
|
|
mutex_lock(&memcg->thresholds_lock);
|
|
|
|
if (type == _MEM) {
|
|
thresholds = &memcg->thresholds;
|
|
usage = mem_cgroup_usage(memcg, false);
|
|
} else if (type == _MEMSWAP) {
|
|
thresholds = &memcg->memsw_thresholds;
|
|
usage = mem_cgroup_usage(memcg, true);
|
|
} else
|
|
BUG();
|
|
|
|
/* Check if a threshold crossed before adding a new one */
|
|
if (thresholds->primary)
|
|
__mem_cgroup_threshold(memcg, type == _MEMSWAP);
|
|
|
|
size = thresholds->primary ? thresholds->primary->size + 1 : 1;
|
|
|
|
/* Allocate memory for new array of thresholds */
|
|
new = kmalloc(struct_size(new, entries, size), GFP_KERNEL);
|
|
if (!new) {
|
|
ret = -ENOMEM;
|
|
goto unlock;
|
|
}
|
|
new->size = size;
|
|
|
|
/* Copy thresholds (if any) to new array */
|
|
if (thresholds->primary) {
|
|
memcpy(new->entries, thresholds->primary->entries, (size - 1) *
|
|
sizeof(struct mem_cgroup_threshold));
|
|
}
|
|
|
|
/* Add new threshold */
|
|
new->entries[size - 1].eventfd = eventfd;
|
|
new->entries[size - 1].threshold = threshold;
|
|
|
|
/* Sort thresholds. Registering of new threshold isn't time-critical */
|
|
sort(new->entries, size, sizeof(struct mem_cgroup_threshold),
|
|
compare_thresholds, NULL);
|
|
|
|
/* Find current threshold */
|
|
new->current_threshold = -1;
|
|
for (i = 0; i < size; i++) {
|
|
if (new->entries[i].threshold <= usage) {
|
|
/*
|
|
* new->current_threshold will not be used until
|
|
* rcu_assign_pointer(), so it's safe to increment
|
|
* it here.
|
|
*/
|
|
++new->current_threshold;
|
|
} else
|
|
break;
|
|
}
|
|
|
|
/* Free old spare buffer and save old primary buffer as spare */
|
|
kfree(thresholds->spare);
|
|
thresholds->spare = thresholds->primary;
|
|
|
|
rcu_assign_pointer(thresholds->primary, new);
|
|
|
|
/* To be sure that nobody uses thresholds */
|
|
synchronize_rcu();
|
|
|
|
unlock:
|
|
mutex_unlock(&memcg->thresholds_lock);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int mem_cgroup_usage_register_event(struct mem_cgroup *memcg,
|
|
struct eventfd_ctx *eventfd, const char *args)
|
|
{
|
|
return __mem_cgroup_usage_register_event(memcg, eventfd, args, _MEM);
|
|
}
|
|
|
|
static int memsw_cgroup_usage_register_event(struct mem_cgroup *memcg,
|
|
struct eventfd_ctx *eventfd, const char *args)
|
|
{
|
|
return __mem_cgroup_usage_register_event(memcg, eventfd, args, _MEMSWAP);
|
|
}
|
|
|
|
static void __mem_cgroup_usage_unregister_event(struct mem_cgroup *memcg,
|
|
struct eventfd_ctx *eventfd, enum res_type type)
|
|
{
|
|
struct mem_cgroup_thresholds *thresholds;
|
|
struct mem_cgroup_threshold_ary *new;
|
|
unsigned long usage;
|
|
int i, j, size;
|
|
|
|
mutex_lock(&memcg->thresholds_lock);
|
|
|
|
if (type == _MEM) {
|
|
thresholds = &memcg->thresholds;
|
|
usage = mem_cgroup_usage(memcg, false);
|
|
} else if (type == _MEMSWAP) {
|
|
thresholds = &memcg->memsw_thresholds;
|
|
usage = mem_cgroup_usage(memcg, true);
|
|
} else
|
|
BUG();
|
|
|
|
if (!thresholds->primary)
|
|
goto unlock;
|
|
|
|
/* Check if a threshold crossed before removing */
|
|
__mem_cgroup_threshold(memcg, type == _MEMSWAP);
|
|
|
|
/* Calculate new number of threshold */
|
|
size = 0;
|
|
for (i = 0; i < thresholds->primary->size; i++) {
|
|
if (thresholds->primary->entries[i].eventfd != eventfd)
|
|
size++;
|
|
}
|
|
|
|
new = thresholds->spare;
|
|
|
|
/* Set thresholds array to NULL if we don't have thresholds */
|
|
if (!size) {
|
|
kfree(new);
|
|
new = NULL;
|
|
goto swap_buffers;
|
|
}
|
|
|
|
new->size = size;
|
|
|
|
/* Copy thresholds and find current threshold */
|
|
new->current_threshold = -1;
|
|
for (i = 0, j = 0; i < thresholds->primary->size; i++) {
|
|
if (thresholds->primary->entries[i].eventfd == eventfd)
|
|
continue;
|
|
|
|
new->entries[j] = thresholds->primary->entries[i];
|
|
if (new->entries[j].threshold <= usage) {
|
|
/*
|
|
* new->current_threshold will not be used
|
|
* until rcu_assign_pointer(), so it's safe to increment
|
|
* it here.
|
|
*/
|
|
++new->current_threshold;
|
|
}
|
|
j++;
|
|
}
|
|
|
|
swap_buffers:
|
|
/* Swap primary and spare array */
|
|
thresholds->spare = thresholds->primary;
|
|
|
|
rcu_assign_pointer(thresholds->primary, new);
|
|
|
|
/* To be sure that nobody uses thresholds */
|
|
synchronize_rcu();
|
|
|
|
/* If all events are unregistered, free the spare array */
|
|
if (!new) {
|
|
kfree(thresholds->spare);
|
|
thresholds->spare = NULL;
|
|
}
|
|
unlock:
|
|
mutex_unlock(&memcg->thresholds_lock);
|
|
}
|
|
|
|
static void mem_cgroup_usage_unregister_event(struct mem_cgroup *memcg,
|
|
struct eventfd_ctx *eventfd)
|
|
{
|
|
return __mem_cgroup_usage_unregister_event(memcg, eventfd, _MEM);
|
|
}
|
|
|
|
static void memsw_cgroup_usage_unregister_event(struct mem_cgroup *memcg,
|
|
struct eventfd_ctx *eventfd)
|
|
{
|
|
return __mem_cgroup_usage_unregister_event(memcg, eventfd, _MEMSWAP);
|
|
}
|
|
|
|
static int mem_cgroup_oom_register_event(struct mem_cgroup *memcg,
|
|
struct eventfd_ctx *eventfd, const char *args)
|
|
{
|
|
struct mem_cgroup_eventfd_list *event;
|
|
|
|
event = kmalloc(sizeof(*event), GFP_KERNEL);
|
|
if (!event)
|
|
return -ENOMEM;
|
|
|
|
spin_lock(&memcg_oom_lock);
|
|
|
|
event->eventfd = eventfd;
|
|
list_add(&event->list, &memcg->oom_notify);
|
|
|
|
/* already in OOM ? */
|
|
if (memcg->under_oom)
|
|
eventfd_signal(eventfd, 1);
|
|
spin_unlock(&memcg_oom_lock);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void mem_cgroup_oom_unregister_event(struct mem_cgroup *memcg,
|
|
struct eventfd_ctx *eventfd)
|
|
{
|
|
struct mem_cgroup_eventfd_list *ev, *tmp;
|
|
|
|
spin_lock(&memcg_oom_lock);
|
|
|
|
list_for_each_entry_safe(ev, tmp, &memcg->oom_notify, list) {
|
|
if (ev->eventfd == eventfd) {
|
|
list_del(&ev->list);
|
|
kfree(ev);
|
|
}
|
|
}
|
|
|
|
spin_unlock(&memcg_oom_lock);
|
|
}
|
|
|
|
static int mem_cgroup_oom_control_read(struct seq_file *sf, void *v)
|
|
{
|
|
struct mem_cgroup *memcg = mem_cgroup_from_seq(sf);
|
|
|
|
seq_printf(sf, "oom_kill_disable %d\n", memcg->oom_kill_disable);
|
|
seq_printf(sf, "under_oom %d\n", (bool)memcg->under_oom);
|
|
seq_printf(sf, "oom_kill %lu\n",
|
|
atomic_long_read(&memcg->memory_events[MEMCG_OOM_KILL]));
|
|
return 0;
|
|
}
|
|
|
|
static int mem_cgroup_oom_control_write(struct cgroup_subsys_state *css,
|
|
struct cftype *cft, u64 val)
|
|
{
|
|
struct mem_cgroup *memcg = mem_cgroup_from_css(css);
|
|
|
|
/* cannot set to root cgroup and only 0 and 1 are allowed */
|
|
if (!css->parent || !((val == 0) || (val == 1)))
|
|
return -EINVAL;
|
|
|
|
memcg->oom_kill_disable = val;
|
|
if (!val)
|
|
memcg_oom_recover(memcg);
|
|
|
|
return 0;
|
|
}
|
|
|
|
#ifdef CONFIG_CGROUP_WRITEBACK
|
|
|
|
#include <trace/events/writeback.h>
|
|
|
|
static int memcg_wb_domain_init(struct mem_cgroup *memcg, gfp_t gfp)
|
|
{
|
|
return wb_domain_init(&memcg->cgwb_domain, gfp);
|
|
}
|
|
|
|
static void memcg_wb_domain_exit(struct mem_cgroup *memcg)
|
|
{
|
|
wb_domain_exit(&memcg->cgwb_domain);
|
|
}
|
|
|
|
static void memcg_wb_domain_size_changed(struct mem_cgroup *memcg)
|
|
{
|
|
wb_domain_size_changed(&memcg->cgwb_domain);
|
|
}
|
|
|
|
struct wb_domain *mem_cgroup_wb_domain(struct bdi_writeback *wb)
|
|
{
|
|
struct mem_cgroup *memcg = mem_cgroup_from_css(wb->memcg_css);
|
|
|
|
if (!memcg->css.parent)
|
|
return NULL;
|
|
|
|
return &memcg->cgwb_domain;
|
|
}
|
|
|
|
/*
|
|
* idx can be of type enum memcg_stat_item or node_stat_item.
|
|
* Keep in sync with memcg_exact_page().
|
|
*/
|
|
static unsigned long memcg_exact_page_state(struct mem_cgroup *memcg, int idx)
|
|
{
|
|
long x = atomic_long_read(&memcg->vmstats[idx]);
|
|
int cpu;
|
|
|
|
for_each_online_cpu(cpu)
|
|
x += per_cpu_ptr(memcg->vmstats_percpu, cpu)->stat[idx];
|
|
if (x < 0)
|
|
x = 0;
|
|
return x;
|
|
}
|
|
|
|
/**
|
|
* mem_cgroup_wb_stats - retrieve writeback related stats from its memcg
|
|
* @wb: bdi_writeback in question
|
|
* @pfilepages: out parameter for number of file pages
|
|
* @pheadroom: out parameter for number of allocatable pages according to memcg
|
|
* @pdirty: out parameter for number of dirty pages
|
|
* @pwriteback: out parameter for number of pages under writeback
|
|
*
|
|
* Determine the numbers of file, headroom, dirty, and writeback pages in
|
|
* @wb's memcg. File, dirty and writeback are self-explanatory. Headroom
|
|
* is a bit more involved.
|
|
*
|
|
* A memcg's headroom is "min(max, high) - used". In the hierarchy, the
|
|
* headroom is calculated as the lowest headroom of itself and the
|
|
* ancestors. Note that this doesn't consider the actual amount of
|
|
* available memory in the system. The caller should further cap
|
|
* *@pheadroom accordingly.
|
|
*/
|
|
void mem_cgroup_wb_stats(struct bdi_writeback *wb, unsigned long *pfilepages,
|
|
unsigned long *pheadroom, unsigned long *pdirty,
|
|
unsigned long *pwriteback)
|
|
{
|
|
struct mem_cgroup *memcg = mem_cgroup_from_css(wb->memcg_css);
|
|
struct mem_cgroup *parent;
|
|
|
|
*pdirty = memcg_exact_page_state(memcg, NR_FILE_DIRTY);
|
|
|
|
/* this should eventually include NR_UNSTABLE_NFS */
|
|
*pwriteback = memcg_exact_page_state(memcg, NR_WRITEBACK);
|
|
*pfilepages = memcg_exact_page_state(memcg, NR_INACTIVE_FILE) +
|
|
memcg_exact_page_state(memcg, NR_ACTIVE_FILE);
|
|
*pheadroom = PAGE_COUNTER_MAX;
|
|
|
|
while ((parent = parent_mem_cgroup(memcg))) {
|
|
unsigned long ceiling = min(memcg->memory.max, memcg->high);
|
|
unsigned long used = page_counter_read(&memcg->memory);
|
|
|
|
*pheadroom = min(*pheadroom, ceiling - min(ceiling, used));
|
|
memcg = parent;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Foreign dirty flushing
|
|
*
|
|
* There's an inherent mismatch between memcg and writeback. The former
|
|
* trackes ownership per-page while the latter per-inode. This was a
|
|
* deliberate design decision because honoring per-page ownership in the
|
|
* writeback path is complicated, may lead to higher CPU and IO overheads
|
|
* and deemed unnecessary given that write-sharing an inode across
|
|
* different cgroups isn't a common use-case.
|
|
*
|
|
* Combined with inode majority-writer ownership switching, this works well
|
|
* enough in most cases but there are some pathological cases. For
|
|
* example, let's say there are two cgroups A and B which keep writing to
|
|
* different but confined parts of the same inode. B owns the inode and
|
|
* A's memory is limited far below B's. A's dirty ratio can rise enough to
|
|
* trigger balance_dirty_pages() sleeps but B's can be low enough to avoid
|
|
* triggering background writeback. A will be slowed down without a way to
|
|
* make writeback of the dirty pages happen.
|
|
*
|
|
* Conditions like the above can lead to a cgroup getting repatedly and
|
|
* severely throttled after making some progress after each
|
|
* dirty_expire_interval while the underyling IO device is almost
|
|
* completely idle.
|
|
*
|
|
* Solving this problem completely requires matching the ownership tracking
|
|
* granularities between memcg and writeback in either direction. However,
|
|
* the more egregious behaviors can be avoided by simply remembering the
|
|
* most recent foreign dirtying events and initiating remote flushes on
|
|
* them when local writeback isn't enough to keep the memory clean enough.
|
|
*
|
|
* The following two functions implement such mechanism. When a foreign
|
|
* page - a page whose memcg and writeback ownerships don't match - is
|
|
* dirtied, mem_cgroup_track_foreign_dirty() records the inode owning
|
|
* bdi_writeback on the page owning memcg. When balance_dirty_pages()
|
|
* decides that the memcg needs to sleep due to high dirty ratio, it calls
|
|
* mem_cgroup_flush_foreign() which queues writeback on the recorded
|
|
* foreign bdi_writebacks which haven't expired. Both the numbers of
|
|
* recorded bdi_writebacks and concurrent in-flight foreign writebacks are
|
|
* limited to MEMCG_CGWB_FRN_CNT.
|
|
*
|
|
* The mechanism only remembers IDs and doesn't hold any object references.
|
|
* As being wrong occasionally doesn't matter, updates and accesses to the
|
|
* records are lockless and racy.
|
|
*/
|
|
void mem_cgroup_track_foreign_dirty_slowpath(struct page *page,
|
|
struct bdi_writeback *wb)
|
|
{
|
|
struct mem_cgroup *memcg = page->mem_cgroup;
|
|
struct memcg_cgwb_frn *frn;
|
|
u64 now = get_jiffies_64();
|
|
u64 oldest_at = now;
|
|
int oldest = -1;
|
|
int i;
|
|
|
|
trace_track_foreign_dirty(page, wb);
|
|
|
|
/*
|
|
* Pick the slot to use. If there is already a slot for @wb, keep
|
|
* using it. If not replace the oldest one which isn't being
|
|
* written out.
|
|
*/
|
|
for (i = 0; i < MEMCG_CGWB_FRN_CNT; i++) {
|
|
frn = &memcg->cgwb_frn[i];
|
|
if (frn->bdi_id == wb->bdi->id &&
|
|
frn->memcg_id == wb->memcg_css->id)
|
|
break;
|
|
if (time_before64(frn->at, oldest_at) &&
|
|
atomic_read(&frn->done.cnt) == 1) {
|
|
oldest = i;
|
|
oldest_at = frn->at;
|
|
}
|
|
}
|
|
|
|
if (i < MEMCG_CGWB_FRN_CNT) {
|
|
/*
|
|
* Re-using an existing one. Update timestamp lazily to
|
|
* avoid making the cacheline hot. We want them to be
|
|
* reasonably up-to-date and significantly shorter than
|
|
* dirty_expire_interval as that's what expires the record.
|
|
* Use the shorter of 1s and dirty_expire_interval / 8.
|
|
*/
|
|
unsigned long update_intv =
|
|
min_t(unsigned long, HZ,
|
|
msecs_to_jiffies(dirty_expire_interval * 10) / 8);
|
|
|
|
if (time_before64(frn->at, now - update_intv))
|
|
frn->at = now;
|
|
} else if (oldest >= 0) {
|
|
/* replace the oldest free one */
|
|
frn = &memcg->cgwb_frn[oldest];
|
|
frn->bdi_id = wb->bdi->id;
|
|
frn->memcg_id = wb->memcg_css->id;
|
|
frn->at = now;
|
|
}
|
|
}
|
|
|
|
/* issue foreign writeback flushes for recorded foreign dirtying events */
|
|
void mem_cgroup_flush_foreign(struct bdi_writeback *wb)
|
|
{
|
|
struct mem_cgroup *memcg = mem_cgroup_from_css(wb->memcg_css);
|
|
unsigned long intv = msecs_to_jiffies(dirty_expire_interval * 10);
|
|
u64 now = jiffies_64;
|
|
int i;
|
|
|
|
for (i = 0; i < MEMCG_CGWB_FRN_CNT; i++) {
|
|
struct memcg_cgwb_frn *frn = &memcg->cgwb_frn[i];
|
|
|
|
/*
|
|
* If the record is older than dirty_expire_interval,
|
|
* writeback on it has already started. No need to kick it
|
|
* off again. Also, don't start a new one if there's
|
|
* already one in flight.
|
|
*/
|
|
if (time_after64(frn->at, now - intv) &&
|
|
atomic_read(&frn->done.cnt) == 1) {
|
|
frn->at = 0;
|
|
trace_flush_foreign(wb, frn->bdi_id, frn->memcg_id);
|
|
cgroup_writeback_by_id(frn->bdi_id, frn->memcg_id, 0,
|
|
WB_REASON_FOREIGN_FLUSH,
|
|
&frn->done);
|
|
}
|
|
}
|
|
}
|
|
|
|
#else /* CONFIG_CGROUP_WRITEBACK */
|
|
|
|
static int memcg_wb_domain_init(struct mem_cgroup *memcg, gfp_t gfp)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static void memcg_wb_domain_exit(struct mem_cgroup *memcg)
|
|
{
|
|
}
|
|
|
|
static void memcg_wb_domain_size_changed(struct mem_cgroup *memcg)
|
|
{
|
|
}
|
|
|
|
#endif /* CONFIG_CGROUP_WRITEBACK */
|
|
|
|
/*
|
|
* DO NOT USE IN NEW FILES.
|
|
*
|
|
* "cgroup.event_control" implementation.
|
|
*
|
|
* This is way over-engineered. It tries to support fully configurable
|
|
* events for each user. Such level of flexibility is completely
|
|
* unnecessary especially in the light of the planned unified hierarchy.
|
|
*
|
|
* Please deprecate this and replace with something simpler if at all
|
|
* possible.
|
|
*/
|
|
|
|
/*
|
|
* Unregister event and free resources.
|
|
*
|
|
* Gets called from workqueue.
|
|
*/
|
|
static void memcg_event_remove(struct work_struct *work)
|
|
{
|
|
struct mem_cgroup_event *event =
|
|
container_of(work, struct mem_cgroup_event, remove);
|
|
struct mem_cgroup *memcg = event->memcg;
|
|
|
|
remove_wait_queue(event->wqh, &event->wait);
|
|
|
|
event->unregister_event(memcg, event->eventfd);
|
|
|
|
/* Notify userspace the event is going away. */
|
|
eventfd_signal(event->eventfd, 1);
|
|
|
|
eventfd_ctx_put(event->eventfd);
|
|
kfree(event);
|
|
css_put(&memcg->css);
|
|
}
|
|
|
|
/*
|
|
* Gets called on EPOLLHUP on eventfd when user closes it.
|
|
*
|
|
* Called with wqh->lock held and interrupts disabled.
|
|
*/
|
|
static int memcg_event_wake(wait_queue_entry_t *wait, unsigned mode,
|
|
int sync, void *key)
|
|
{
|
|
struct mem_cgroup_event *event =
|
|
container_of(wait, struct mem_cgroup_event, wait);
|
|
struct mem_cgroup *memcg = event->memcg;
|
|
__poll_t flags = key_to_poll(key);
|
|
|
|
if (flags & EPOLLHUP) {
|
|
/*
|
|
* If the event has been detached at cgroup removal, we
|
|
* can simply return knowing the other side will cleanup
|
|
* for us.
|
|
*
|
|
* We can't race against event freeing since the other
|
|
* side will require wqh->lock via remove_wait_queue(),
|
|
* which we hold.
|
|
*/
|
|
spin_lock(&memcg->event_list_lock);
|
|
if (!list_empty(&event->list)) {
|
|
list_del_init(&event->list);
|
|
/*
|
|
* We are in atomic context, but cgroup_event_remove()
|
|
* may sleep, so we have to call it in workqueue.
|
|
*/
|
|
schedule_work(&event->remove);
|
|
}
|
|
spin_unlock(&memcg->event_list_lock);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void memcg_event_ptable_queue_proc(struct file *file,
|
|
wait_queue_head_t *wqh, poll_table *pt)
|
|
{
|
|
struct mem_cgroup_event *event =
|
|
container_of(pt, struct mem_cgroup_event, pt);
|
|
|
|
event->wqh = wqh;
|
|
add_wait_queue(wqh, &event->wait);
|
|
}
|
|
|
|
/*
|
|
* DO NOT USE IN NEW FILES.
|
|
*
|
|
* Parse input and register new cgroup event handler.
|
|
*
|
|
* Input must be in format '<event_fd> <control_fd> <args>'.
|
|
* Interpretation of args is defined by control file implementation.
|
|
*/
|
|
static ssize_t memcg_write_event_control(struct kernfs_open_file *of,
|
|
char *buf, size_t nbytes, loff_t off)
|
|
{
|
|
struct cgroup_subsys_state *css = of_css(of);
|
|
struct mem_cgroup *memcg = mem_cgroup_from_css(css);
|
|
struct mem_cgroup_event *event;
|
|
struct cgroup_subsys_state *cfile_css;
|
|
unsigned int efd, cfd;
|
|
struct fd efile;
|
|
struct fd cfile;
|
|
const char *name;
|
|
char *endp;
|
|
int ret;
|
|
|
|
buf = strstrip(buf);
|
|
|
|
efd = simple_strtoul(buf, &endp, 10);
|
|
if (*endp != ' ')
|
|
return -EINVAL;
|
|
buf = endp + 1;
|
|
|
|
cfd = simple_strtoul(buf, &endp, 10);
|
|
if ((*endp != ' ') && (*endp != '\0'))
|
|
return -EINVAL;
|
|
buf = endp + 1;
|
|
|
|
event = kzalloc(sizeof(*event), GFP_KERNEL);
|
|
if (!event)
|
|
return -ENOMEM;
|
|
|
|
event->memcg = memcg;
|
|
INIT_LIST_HEAD(&event->list);
|
|
init_poll_funcptr(&event->pt, memcg_event_ptable_queue_proc);
|
|
init_waitqueue_func_entry(&event->wait, memcg_event_wake);
|
|
INIT_WORK(&event->remove, memcg_event_remove);
|
|
|
|
efile = fdget(efd);
|
|
if (!efile.file) {
|
|
ret = -EBADF;
|
|
goto out_kfree;
|
|
}
|
|
|
|
event->eventfd = eventfd_ctx_fileget(efile.file);
|
|
if (IS_ERR(event->eventfd)) {
|
|
ret = PTR_ERR(event->eventfd);
|
|
goto out_put_efile;
|
|
}
|
|
|
|
cfile = fdget(cfd);
|
|
if (!cfile.file) {
|
|
ret = -EBADF;
|
|
goto out_put_eventfd;
|
|
}
|
|
|
|
/* the process need read permission on control file */
|
|
/* AV: shouldn't we check that it's been opened for read instead? */
|
|
ret = inode_permission(file_inode(cfile.file), MAY_READ);
|
|
if (ret < 0)
|
|
goto out_put_cfile;
|
|
|
|
/*
|
|
* Determine the event callbacks and set them in @event. This used
|
|
* to be done via struct cftype but cgroup core no longer knows
|
|
* about these events. The following is crude but the whole thing
|
|
* is for compatibility anyway.
|
|
*
|
|
* DO NOT ADD NEW FILES.
|
|
*/
|
|
name = cfile.file->f_path.dentry->d_name.name;
|
|
|
|
if (!strcmp(name, "memory.usage_in_bytes")) {
|
|
event->register_event = mem_cgroup_usage_register_event;
|
|
event->unregister_event = mem_cgroup_usage_unregister_event;
|
|
} else if (!strcmp(name, "memory.oom_control")) {
|
|
event->register_event = mem_cgroup_oom_register_event;
|
|
event->unregister_event = mem_cgroup_oom_unregister_event;
|
|
} else if (!strcmp(name, "memory.pressure_level")) {
|
|
event->register_event = vmpressure_register_event;
|
|
event->unregister_event = vmpressure_unregister_event;
|
|
} else if (!strcmp(name, "memory.memsw.usage_in_bytes")) {
|
|
event->register_event = memsw_cgroup_usage_register_event;
|
|
event->unregister_event = memsw_cgroup_usage_unregister_event;
|
|
} else {
|
|
ret = -EINVAL;
|
|
goto out_put_cfile;
|
|
}
|
|
|
|
/*
|
|
* Verify @cfile should belong to @css. Also, remaining events are
|
|
* automatically removed on cgroup destruction but the removal is
|
|
* asynchronous, so take an extra ref on @css.
|
|
*/
|
|
cfile_css = css_tryget_online_from_dir(cfile.file->f_path.dentry->d_parent,
|
|
&memory_cgrp_subsys);
|
|
ret = -EINVAL;
|
|
if (IS_ERR(cfile_css))
|
|
goto out_put_cfile;
|
|
if (cfile_css != css) {
|
|
css_put(cfile_css);
|
|
goto out_put_cfile;
|
|
}
|
|
|
|
ret = event->register_event(memcg, event->eventfd, buf);
|
|
if (ret)
|
|
goto out_put_css;
|
|
|
|
vfs_poll(efile.file, &event->pt);
|
|
|
|
spin_lock(&memcg->event_list_lock);
|
|
list_add(&event->list, &memcg->event_list);
|
|
spin_unlock(&memcg->event_list_lock);
|
|
|
|
fdput(cfile);
|
|
fdput(efile);
|
|
|
|
return nbytes;
|
|
|
|
out_put_css:
|
|
css_put(css);
|
|
out_put_cfile:
|
|
fdput(cfile);
|
|
out_put_eventfd:
|
|
eventfd_ctx_put(event->eventfd);
|
|
out_put_efile:
|
|
fdput(efile);
|
|
out_kfree:
|
|
kfree(event);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static struct cftype mem_cgroup_legacy_files[] = {
|
|
{
|
|
.name = "usage_in_bytes",
|
|
.private = MEMFILE_PRIVATE(_MEM, RES_USAGE),
|
|
.read_u64 = mem_cgroup_read_u64,
|
|
},
|
|
{
|
|
.name = "max_usage_in_bytes",
|
|
.private = MEMFILE_PRIVATE(_MEM, RES_MAX_USAGE),
|
|
.write = mem_cgroup_reset,
|
|
.read_u64 = mem_cgroup_read_u64,
|
|
},
|
|
{
|
|
.name = "limit_in_bytes",
|
|
.private = MEMFILE_PRIVATE(_MEM, RES_LIMIT),
|
|
.write = mem_cgroup_write,
|
|
.read_u64 = mem_cgroup_read_u64,
|
|
},
|
|
{
|
|
.name = "soft_limit_in_bytes",
|
|
.private = MEMFILE_PRIVATE(_MEM, RES_SOFT_LIMIT),
|
|
.write = mem_cgroup_write,
|
|
.read_u64 = mem_cgroup_read_u64,
|
|
},
|
|
{
|
|
.name = "failcnt",
|
|
.private = MEMFILE_PRIVATE(_MEM, RES_FAILCNT),
|
|
.write = mem_cgroup_reset,
|
|
.read_u64 = mem_cgroup_read_u64,
|
|
},
|
|
{
|
|
.name = "stat",
|
|
.seq_show = memcg_stat_show,
|
|
},
|
|
{
|
|
.name = "force_empty",
|
|
.write = mem_cgroup_force_empty_write,
|
|
},
|
|
{
|
|
.name = "use_hierarchy",
|
|
.write_u64 = mem_cgroup_hierarchy_write,
|
|
.read_u64 = mem_cgroup_hierarchy_read,
|
|
},
|
|
{
|
|
.name = "cgroup.event_control", /* XXX: for compat */
|
|
.write = memcg_write_event_control,
|
|
.flags = CFTYPE_NO_PREFIX | CFTYPE_WORLD_WRITABLE,
|
|
},
|
|
{
|
|
.name = "swappiness",
|
|
.read_u64 = mem_cgroup_swappiness_read,
|
|
.write_u64 = mem_cgroup_swappiness_write,
|
|
},
|
|
{
|
|
.name = "move_charge_at_immigrate",
|
|
.read_u64 = mem_cgroup_move_charge_read,
|
|
.write_u64 = mem_cgroup_move_charge_write,
|
|
},
|
|
{
|
|
.name = "oom_control",
|
|
.seq_show = mem_cgroup_oom_control_read,
|
|
.write_u64 = mem_cgroup_oom_control_write,
|
|
.private = MEMFILE_PRIVATE(_OOM_TYPE, OOM_CONTROL),
|
|
},
|
|
{
|
|
.name = "pressure_level",
|
|
},
|
|
#ifdef CONFIG_NUMA
|
|
{
|
|
.name = "numa_stat",
|
|
.seq_show = memcg_numa_stat_show,
|
|
},
|
|
#endif
|
|
{
|
|
.name = "kmem.limit_in_bytes",
|
|
.private = MEMFILE_PRIVATE(_KMEM, RES_LIMIT),
|
|
.write = mem_cgroup_write,
|
|
.read_u64 = mem_cgroup_read_u64,
|
|
},
|
|
{
|
|
.name = "kmem.usage_in_bytes",
|
|
.private = MEMFILE_PRIVATE(_KMEM, RES_USAGE),
|
|
.read_u64 = mem_cgroup_read_u64,
|
|
},
|
|
{
|
|
.name = "kmem.failcnt",
|
|
.private = MEMFILE_PRIVATE(_KMEM, RES_FAILCNT),
|
|
.write = mem_cgroup_reset,
|
|
.read_u64 = mem_cgroup_read_u64,
|
|
},
|
|
{
|
|
.name = "kmem.max_usage_in_bytes",
|
|
.private = MEMFILE_PRIVATE(_KMEM, RES_MAX_USAGE),
|
|
.write = mem_cgroup_reset,
|
|
.read_u64 = mem_cgroup_read_u64,
|
|
},
|
|
#if defined(CONFIG_SLAB) || defined(CONFIG_SLUB_DEBUG)
|
|
{
|
|
.name = "kmem.slabinfo",
|
|
.seq_start = memcg_slab_start,
|
|
.seq_next = memcg_slab_next,
|
|
.seq_stop = memcg_slab_stop,
|
|
.seq_show = memcg_slab_show,
|
|
},
|
|
#endif
|
|
{
|
|
.name = "kmem.tcp.limit_in_bytes",
|
|
.private = MEMFILE_PRIVATE(_TCP, RES_LIMIT),
|
|
.write = mem_cgroup_write,
|
|
.read_u64 = mem_cgroup_read_u64,
|
|
},
|
|
{
|
|
.name = "kmem.tcp.usage_in_bytes",
|
|
.private = MEMFILE_PRIVATE(_TCP, RES_USAGE),
|
|
.read_u64 = mem_cgroup_read_u64,
|
|
},
|
|
{
|
|
.name = "kmem.tcp.failcnt",
|
|
.private = MEMFILE_PRIVATE(_TCP, RES_FAILCNT),
|
|
.write = mem_cgroup_reset,
|
|
.read_u64 = mem_cgroup_read_u64,
|
|
},
|
|
{
|
|
.name = "kmem.tcp.max_usage_in_bytes",
|
|
.private = MEMFILE_PRIVATE(_TCP, RES_MAX_USAGE),
|
|
.write = mem_cgroup_reset,
|
|
.read_u64 = mem_cgroup_read_u64,
|
|
},
|
|
{ }, /* terminate */
|
|
};
|
|
|
|
/*
|
|
* Private memory cgroup IDR
|
|
*
|
|
* Swap-out records and page cache shadow entries need to store memcg
|
|
* references in constrained space, so we maintain an ID space that is
|
|
* limited to 16 bit (MEM_CGROUP_ID_MAX), limiting the total number of
|
|
* memory-controlled cgroups to 64k.
|
|
*
|
|
* However, there usually are many references to the oflline CSS after
|
|
* the cgroup has been destroyed, such as page cache or reclaimable
|
|
* slab objects, that don't need to hang on to the ID. We want to keep
|
|
* those dead CSS from occupying IDs, or we might quickly exhaust the
|
|
* relatively small ID space and prevent the creation of new cgroups
|
|
* even when there are much fewer than 64k cgroups - possibly none.
|
|
*
|
|
* Maintain a private 16-bit ID space for memcg, and allow the ID to
|
|
* be freed and recycled when it's no longer needed, which is usually
|
|
* when the CSS is offlined.
|
|
*
|
|
* The only exception to that are records of swapped out tmpfs/shmem
|
|
* pages that need to be attributed to live ancestors on swapin. But
|
|
* those references are manageable from userspace.
|
|
*/
|
|
|
|
static DEFINE_IDR(mem_cgroup_idr);
|
|
|
|
static void mem_cgroup_id_remove(struct mem_cgroup *memcg)
|
|
{
|
|
if (memcg->id.id > 0) {
|
|
idr_remove(&mem_cgroup_idr, memcg->id.id);
|
|
memcg->id.id = 0;
|
|
}
|
|
}
|
|
|
|
static void mem_cgroup_id_get_many(struct mem_cgroup *memcg, unsigned int n)
|
|
{
|
|
refcount_add(n, &memcg->id.ref);
|
|
}
|
|
|
|
static void mem_cgroup_id_put_many(struct mem_cgroup *memcg, unsigned int n)
|
|
{
|
|
if (refcount_sub_and_test(n, &memcg->id.ref)) {
|
|
mem_cgroup_id_remove(memcg);
|
|
|
|
/* Memcg ID pins CSS */
|
|
css_put(&memcg->css);
|
|
}
|
|
}
|
|
|
|
static inline void mem_cgroup_id_put(struct mem_cgroup *memcg)
|
|
{
|
|
mem_cgroup_id_put_many(memcg, 1);
|
|
}
|
|
|
|
/**
|
|
* mem_cgroup_from_id - look up a memcg from a memcg id
|
|
* @id: the memcg id to look up
|
|
*
|
|
* Caller must hold rcu_read_lock().
|
|
*/
|
|
struct mem_cgroup *mem_cgroup_from_id(unsigned short id)
|
|
{
|
|
WARN_ON_ONCE(!rcu_read_lock_held());
|
|
return idr_find(&mem_cgroup_idr, id);
|
|
}
|
|
|
|
static int alloc_mem_cgroup_per_node_info(struct mem_cgroup *memcg, int node)
|
|
{
|
|
struct mem_cgroup_per_node *pn;
|
|
int tmp = node;
|
|
/*
|
|
* This routine is called against possible nodes.
|
|
* But it's BUG to call kmalloc() against offline node.
|
|
*
|
|
* TODO: this routine can waste much memory for nodes which will
|
|
* never be onlined. It's better to use memory hotplug callback
|
|
* function.
|
|
*/
|
|
if (!node_state(node, N_NORMAL_MEMORY))
|
|
tmp = -1;
|
|
pn = kzalloc_node(sizeof(*pn), GFP_KERNEL, tmp);
|
|
if (!pn)
|
|
return 1;
|
|
|
|
pn->lruvec_stat_local = alloc_percpu(struct lruvec_stat);
|
|
if (!pn->lruvec_stat_local) {
|
|
kfree(pn);
|
|
return 1;
|
|
}
|
|
|
|
pn->lruvec_stat_cpu = alloc_percpu(struct lruvec_stat);
|
|
if (!pn->lruvec_stat_cpu) {
|
|
free_percpu(pn->lruvec_stat_local);
|
|
kfree(pn);
|
|
return 1;
|
|
}
|
|
|
|
lruvec_init(&pn->lruvec);
|
|
pn->usage_in_excess = 0;
|
|
pn->on_tree = false;
|
|
pn->memcg = memcg;
|
|
|
|
memcg->nodeinfo[node] = pn;
|
|
return 0;
|
|
}
|
|
|
|
static void free_mem_cgroup_per_node_info(struct mem_cgroup *memcg, int node)
|
|
{
|
|
struct mem_cgroup_per_node *pn = memcg->nodeinfo[node];
|
|
|
|
if (!pn)
|
|
return;
|
|
|
|
free_percpu(pn->lruvec_stat_cpu);
|
|
free_percpu(pn->lruvec_stat_local);
|
|
kfree(pn);
|
|
}
|
|
|
|
static void __mem_cgroup_free(struct mem_cgroup *memcg)
|
|
{
|
|
int node;
|
|
|
|
/*
|
|
* Flush percpu vmstats and vmevents to guarantee the value correctness
|
|
* on parent's and all ancestor levels.
|
|
*/
|
|
memcg_flush_percpu_vmstats(memcg, false);
|
|
memcg_flush_percpu_vmevents(memcg);
|
|
for_each_node(node)
|
|
free_mem_cgroup_per_node_info(memcg, node);
|
|
free_percpu(memcg->vmstats_percpu);
|
|
free_percpu(memcg->vmstats_local);
|
|
kfree(memcg);
|
|
}
|
|
|
|
static void mem_cgroup_free(struct mem_cgroup *memcg)
|
|
{
|
|
memcg_wb_domain_exit(memcg);
|
|
__mem_cgroup_free(memcg);
|
|
}
|
|
|
|
static struct mem_cgroup *mem_cgroup_alloc(void)
|
|
{
|
|
struct mem_cgroup *memcg;
|
|
unsigned int size;
|
|
int node;
|
|
int __maybe_unused i;
|
|
|
|
size = sizeof(struct mem_cgroup);
|
|
size += nr_node_ids * sizeof(struct mem_cgroup_per_node *);
|
|
|
|
memcg = kzalloc(size, GFP_KERNEL);
|
|
if (!memcg)
|
|
return NULL;
|
|
|
|
memcg->id.id = idr_alloc(&mem_cgroup_idr, NULL,
|
|
1, MEM_CGROUP_ID_MAX,
|
|
GFP_KERNEL);
|
|
if (memcg->id.id < 0)
|
|
goto fail;
|
|
|
|
memcg->vmstats_local = alloc_percpu(struct memcg_vmstats_percpu);
|
|
if (!memcg->vmstats_local)
|
|
goto fail;
|
|
|
|
memcg->vmstats_percpu = alloc_percpu(struct memcg_vmstats_percpu);
|
|
if (!memcg->vmstats_percpu)
|
|
goto fail;
|
|
|
|
for_each_node(node)
|
|
if (alloc_mem_cgroup_per_node_info(memcg, node))
|
|
goto fail;
|
|
|
|
if (memcg_wb_domain_init(memcg, GFP_KERNEL))
|
|
goto fail;
|
|
|
|
INIT_WORK(&memcg->high_work, high_work_func);
|
|
memcg->last_scanned_node = MAX_NUMNODES;
|
|
INIT_LIST_HEAD(&memcg->oom_notify);
|
|
mutex_init(&memcg->thresholds_lock);
|
|
spin_lock_init(&memcg->move_lock);
|
|
vmpressure_init(&memcg->vmpressure);
|
|
INIT_LIST_HEAD(&memcg->event_list);
|
|
spin_lock_init(&memcg->event_list_lock);
|
|
memcg->socket_pressure = jiffies;
|
|
#ifdef CONFIG_MEMCG_KMEM
|
|
memcg->kmemcg_id = -1;
|
|
#endif
|
|
#ifdef CONFIG_CGROUP_WRITEBACK
|
|
INIT_LIST_HEAD(&memcg->cgwb_list);
|
|
for (i = 0; i < MEMCG_CGWB_FRN_CNT; i++)
|
|
memcg->cgwb_frn[i].done =
|
|
__WB_COMPLETION_INIT(&memcg_cgwb_frn_waitq);
|
|
#endif
|
|
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
|
|
spin_lock_init(&memcg->deferred_split_queue.split_queue_lock);
|
|
INIT_LIST_HEAD(&memcg->deferred_split_queue.split_queue);
|
|
memcg->deferred_split_queue.split_queue_len = 0;
|
|
#endif
|
|
idr_replace(&mem_cgroup_idr, memcg, memcg->id.id);
|
|
return memcg;
|
|
fail:
|
|
mem_cgroup_id_remove(memcg);
|
|
__mem_cgroup_free(memcg);
|
|
return NULL;
|
|
}
|
|
|
|
static struct cgroup_subsys_state * __ref
|
|
mem_cgroup_css_alloc(struct cgroup_subsys_state *parent_css)
|
|
{
|
|
struct mem_cgroup *parent = mem_cgroup_from_css(parent_css);
|
|
struct mem_cgroup *memcg;
|
|
long error = -ENOMEM;
|
|
|
|
memcg = mem_cgroup_alloc();
|
|
if (!memcg)
|
|
return ERR_PTR(error);
|
|
|
|
memcg->high = PAGE_COUNTER_MAX;
|
|
memcg->soft_limit = PAGE_COUNTER_MAX;
|
|
if (parent) {
|
|
memcg->swappiness = mem_cgroup_swappiness(parent);
|
|
memcg->oom_kill_disable = parent->oom_kill_disable;
|
|
}
|
|
if (parent && parent->use_hierarchy) {
|
|
memcg->use_hierarchy = true;
|
|
page_counter_init(&memcg->memory, &parent->memory);
|
|
page_counter_init(&memcg->swap, &parent->swap);
|
|
page_counter_init(&memcg->memsw, &parent->memsw);
|
|
page_counter_init(&memcg->kmem, &parent->kmem);
|
|
page_counter_init(&memcg->tcpmem, &parent->tcpmem);
|
|
} else {
|
|
page_counter_init(&memcg->memory, NULL);
|
|
page_counter_init(&memcg->swap, NULL);
|
|
page_counter_init(&memcg->memsw, NULL);
|
|
page_counter_init(&memcg->kmem, NULL);
|
|
page_counter_init(&memcg->tcpmem, NULL);
|
|
/*
|
|
* Deeper hierachy with use_hierarchy == false doesn't make
|
|
* much sense so let cgroup subsystem know about this
|
|
* unfortunate state in our controller.
|
|
*/
|
|
if (parent != root_mem_cgroup)
|
|
memory_cgrp_subsys.broken_hierarchy = true;
|
|
}
|
|
|
|
/* The following stuff does not apply to the root */
|
|
if (!parent) {
|
|
#ifdef CONFIG_MEMCG_KMEM
|
|
INIT_LIST_HEAD(&memcg->kmem_caches);
|
|
#endif
|
|
root_mem_cgroup = memcg;
|
|
return &memcg->css;
|
|
}
|
|
|
|
error = memcg_online_kmem(memcg);
|
|
if (error)
|
|
goto fail;
|
|
|
|
if (cgroup_subsys_on_dfl(memory_cgrp_subsys) && !cgroup_memory_nosocket)
|
|
static_branch_inc(&memcg_sockets_enabled_key);
|
|
|
|
return &memcg->css;
|
|
fail:
|
|
mem_cgroup_id_remove(memcg);
|
|
mem_cgroup_free(memcg);
|
|
return ERR_PTR(-ENOMEM);
|
|
}
|
|
|
|
static int mem_cgroup_css_online(struct cgroup_subsys_state *css)
|
|
{
|
|
struct mem_cgroup *memcg = mem_cgroup_from_css(css);
|
|
|
|
/*
|
|
* A memcg must be visible for memcg_expand_shrinker_maps()
|
|
* by the time the maps are allocated. So, we allocate maps
|
|
* here, when for_each_mem_cgroup() can't skip it.
|
|
*/
|
|
if (memcg_alloc_shrinker_maps(memcg)) {
|
|
mem_cgroup_id_remove(memcg);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
/* Online state pins memcg ID, memcg ID pins CSS */
|
|
refcount_set(&memcg->id.ref, 1);
|
|
css_get(css);
|
|
return 0;
|
|
}
|
|
|
|
static void mem_cgroup_css_offline(struct cgroup_subsys_state *css)
|
|
{
|
|
struct mem_cgroup *memcg = mem_cgroup_from_css(css);
|
|
struct mem_cgroup_event *event, *tmp;
|
|
|
|
/*
|
|
* Unregister events and notify userspace.
|
|
* Notify userspace about cgroup removing only after rmdir of cgroup
|
|
* directory to avoid race between userspace and kernelspace.
|
|
*/
|
|
spin_lock(&memcg->event_list_lock);
|
|
list_for_each_entry_safe(event, tmp, &memcg->event_list, list) {
|
|
list_del_init(&event->list);
|
|
schedule_work(&event->remove);
|
|
}
|
|
spin_unlock(&memcg->event_list_lock);
|
|
|
|
page_counter_set_min(&memcg->memory, 0);
|
|
page_counter_set_low(&memcg->memory, 0);
|
|
|
|
memcg_offline_kmem(memcg);
|
|
wb_memcg_offline(memcg);
|
|
|
|
drain_all_stock(memcg);
|
|
|
|
mem_cgroup_id_put(memcg);
|
|
}
|
|
|
|
static void mem_cgroup_css_released(struct cgroup_subsys_state *css)
|
|
{
|
|
struct mem_cgroup *memcg = mem_cgroup_from_css(css);
|
|
|
|
invalidate_reclaim_iterators(memcg);
|
|
}
|
|
|
|
static void mem_cgroup_css_free(struct cgroup_subsys_state *css)
|
|
{
|
|
struct mem_cgroup *memcg = mem_cgroup_from_css(css);
|
|
int __maybe_unused i;
|
|
|
|
#ifdef CONFIG_CGROUP_WRITEBACK
|
|
for (i = 0; i < MEMCG_CGWB_FRN_CNT; i++)
|
|
wb_wait_for_completion(&memcg->cgwb_frn[i].done);
|
|
#endif
|
|
if (cgroup_subsys_on_dfl(memory_cgrp_subsys) && !cgroup_memory_nosocket)
|
|
static_branch_dec(&memcg_sockets_enabled_key);
|
|
|
|
if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) && memcg->tcpmem_active)
|
|
static_branch_dec(&memcg_sockets_enabled_key);
|
|
|
|
vmpressure_cleanup(&memcg->vmpressure);
|
|
cancel_work_sync(&memcg->high_work);
|
|
mem_cgroup_remove_from_trees(memcg);
|
|
memcg_free_shrinker_maps(memcg);
|
|
memcg_free_kmem(memcg);
|
|
mem_cgroup_free(memcg);
|
|
}
|
|
|
|
/**
|
|
* mem_cgroup_css_reset - reset the states of a mem_cgroup
|
|
* @css: the target css
|
|
*
|
|
* Reset the states of the mem_cgroup associated with @css. This is
|
|
* invoked when the userland requests disabling on the default hierarchy
|
|
* but the memcg is pinned through dependency. The memcg should stop
|
|
* applying policies and should revert to the vanilla state as it may be
|
|
* made visible again.
|
|
*
|
|
* The current implementation only resets the essential configurations.
|
|
* This needs to be expanded to cover all the visible parts.
|
|
*/
|
|
static void mem_cgroup_css_reset(struct cgroup_subsys_state *css)
|
|
{
|
|
struct mem_cgroup *memcg = mem_cgroup_from_css(css);
|
|
|
|
page_counter_set_max(&memcg->memory, PAGE_COUNTER_MAX);
|
|
page_counter_set_max(&memcg->swap, PAGE_COUNTER_MAX);
|
|
page_counter_set_max(&memcg->memsw, PAGE_COUNTER_MAX);
|
|
page_counter_set_max(&memcg->kmem, PAGE_COUNTER_MAX);
|
|
page_counter_set_max(&memcg->tcpmem, PAGE_COUNTER_MAX);
|
|
page_counter_set_min(&memcg->memory, 0);
|
|
page_counter_set_low(&memcg->memory, 0);
|
|
memcg->high = PAGE_COUNTER_MAX;
|
|
memcg->soft_limit = PAGE_COUNTER_MAX;
|
|
memcg_wb_domain_size_changed(memcg);
|
|
}
|
|
|
|
#ifdef CONFIG_MMU
|
|
/* Handlers for move charge at task migration. */
|
|
static int mem_cgroup_do_precharge(unsigned long count)
|
|
{
|
|
int ret;
|
|
|
|
/* Try a single bulk charge without reclaim first, kswapd may wake */
|
|
ret = try_charge(mc.to, GFP_KERNEL & ~__GFP_DIRECT_RECLAIM, count);
|
|
if (!ret) {
|
|
mc.precharge += count;
|
|
return ret;
|
|
}
|
|
|
|
/* Try charges one by one with reclaim, but do not retry */
|
|
while (count--) {
|
|
ret = try_charge(mc.to, GFP_KERNEL | __GFP_NORETRY, 1);
|
|
if (ret)
|
|
return ret;
|
|
mc.precharge++;
|
|
cond_resched();
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
union mc_target {
|
|
struct page *page;
|
|
swp_entry_t ent;
|
|
};
|
|
|
|
enum mc_target_type {
|
|
MC_TARGET_NONE = 0,
|
|
MC_TARGET_PAGE,
|
|
MC_TARGET_SWAP,
|
|
MC_TARGET_DEVICE,
|
|
};
|
|
|
|
static struct page *mc_handle_present_pte(struct vm_area_struct *vma,
|
|
unsigned long addr, pte_t ptent)
|
|
{
|
|
struct page *page = vm_normal_page(vma, addr, ptent);
|
|
|
|
if (!page || !page_mapped(page))
|
|
return NULL;
|
|
if (PageAnon(page)) {
|
|
if (!(mc.flags & MOVE_ANON))
|
|
return NULL;
|
|
} else {
|
|
if (!(mc.flags & MOVE_FILE))
|
|
return NULL;
|
|
}
|
|
if (!get_page_unless_zero(page))
|
|
return NULL;
|
|
|
|
return page;
|
|
}
|
|
|
|
#if defined(CONFIG_SWAP) || defined(CONFIG_DEVICE_PRIVATE)
|
|
static struct page *mc_handle_swap_pte(struct vm_area_struct *vma,
|
|
pte_t ptent, swp_entry_t *entry)
|
|
{
|
|
struct page *page = NULL;
|
|
swp_entry_t ent = pte_to_swp_entry(ptent);
|
|
|
|
if (!(mc.flags & MOVE_ANON) || non_swap_entry(ent))
|
|
return NULL;
|
|
|
|
/*
|
|
* Handle MEMORY_DEVICE_PRIVATE which are ZONE_DEVICE page belonging to
|
|
* a device and because they are not accessible by CPU they are store
|
|
* as special swap entry in the CPU page table.
|
|
*/
|
|
if (is_device_private_entry(ent)) {
|
|
page = device_private_entry_to_page(ent);
|
|
/*
|
|
* MEMORY_DEVICE_PRIVATE means ZONE_DEVICE page and which have
|
|
* a refcount of 1 when free (unlike normal page)
|
|
*/
|
|
if (!page_ref_add_unless(page, 1, 1))
|
|
return NULL;
|
|
return page;
|
|
}
|
|
|
|
/*
|
|
* Because lookup_swap_cache() updates some statistics counter,
|
|
* we call find_get_page() with swapper_space directly.
|
|
*/
|
|
page = find_get_page(swap_address_space(ent), swp_offset(ent));
|
|
if (do_memsw_account())
|
|
entry->val = ent.val;
|
|
|
|
return page;
|
|
}
|
|
#else
|
|
static struct page *mc_handle_swap_pte(struct vm_area_struct *vma,
|
|
pte_t ptent, swp_entry_t *entry)
|
|
{
|
|
return NULL;
|
|
}
|
|
#endif
|
|
|
|
static struct page *mc_handle_file_pte(struct vm_area_struct *vma,
|
|
unsigned long addr, pte_t ptent, swp_entry_t *entry)
|
|
{
|
|
struct page *page = NULL;
|
|
struct address_space *mapping;
|
|
pgoff_t pgoff;
|
|
|
|
if (!vma->vm_file) /* anonymous vma */
|
|
return NULL;
|
|
if (!(mc.flags & MOVE_FILE))
|
|
return NULL;
|
|
|
|
mapping = vma->vm_file->f_mapping;
|
|
pgoff = linear_page_index(vma, addr);
|
|
|
|
/* page is moved even if it's not RSS of this task(page-faulted). */
|
|
#ifdef CONFIG_SWAP
|
|
/* shmem/tmpfs may report page out on swap: account for that too. */
|
|
if (shmem_mapping(mapping)) {
|
|
page = find_get_entry(mapping, pgoff);
|
|
if (xa_is_value(page)) {
|
|
swp_entry_t swp = radix_to_swp_entry(page);
|
|
if (do_memsw_account())
|
|
*entry = swp;
|
|
page = find_get_page(swap_address_space(swp),
|
|
swp_offset(swp));
|
|
}
|
|
} else
|
|
page = find_get_page(mapping, pgoff);
|
|
#else
|
|
page = find_get_page(mapping, pgoff);
|
|
#endif
|
|
return page;
|
|
}
|
|
|
|
/**
|
|
* mem_cgroup_move_account - move account of the page
|
|
* @page: the page
|
|
* @compound: charge the page as compound or small page
|
|
* @from: mem_cgroup which the page is moved from.
|
|
* @to: mem_cgroup which the page is moved to. @from != @to.
|
|
*
|
|
* The caller must make sure the page is not on LRU (isolate_page() is useful.)
|
|
*
|
|
* This function doesn't do "charge" to new cgroup and doesn't do "uncharge"
|
|
* from old cgroup.
|
|
*/
|
|
static int mem_cgroup_move_account(struct page *page,
|
|
bool compound,
|
|
struct mem_cgroup *from,
|
|
struct mem_cgroup *to)
|
|
{
|
|
unsigned long flags;
|
|
unsigned int nr_pages = compound ? hpage_nr_pages(page) : 1;
|
|
int ret;
|
|
bool anon;
|
|
|
|
VM_BUG_ON(from == to);
|
|
VM_BUG_ON_PAGE(PageLRU(page), page);
|
|
VM_BUG_ON(compound && !PageTransHuge(page));
|
|
|
|
/*
|
|
* Prevent mem_cgroup_migrate() from looking at
|
|
* page->mem_cgroup of its source page while we change it.
|
|
*/
|
|
ret = -EBUSY;
|
|
if (!trylock_page(page))
|
|
goto out;
|
|
|
|
ret = -EINVAL;
|
|
if (page->mem_cgroup != from)
|
|
goto out_unlock;
|
|
|
|
anon = PageAnon(page);
|
|
|
|
spin_lock_irqsave(&from->move_lock, flags);
|
|
|
|
if (!anon && page_mapped(page)) {
|
|
__mod_memcg_state(from, NR_FILE_MAPPED, -nr_pages);
|
|
__mod_memcg_state(to, NR_FILE_MAPPED, nr_pages);
|
|
}
|
|
|
|
/*
|
|
* move_lock grabbed above and caller set from->moving_account, so
|
|
* mod_memcg_page_state will serialize updates to PageDirty.
|
|
* So mapping should be stable for dirty pages.
|
|
*/
|
|
if (!anon && PageDirty(page)) {
|
|
struct address_space *mapping = page_mapping(page);
|
|
|
|
if (mapping_cap_account_dirty(mapping)) {
|
|
__mod_memcg_state(from, NR_FILE_DIRTY, -nr_pages);
|
|
__mod_memcg_state(to, NR_FILE_DIRTY, nr_pages);
|
|
}
|
|
}
|
|
|
|
if (PageWriteback(page)) {
|
|
__mod_memcg_state(from, NR_WRITEBACK, -nr_pages);
|
|
__mod_memcg_state(to, NR_WRITEBACK, nr_pages);
|
|
}
|
|
|
|
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
|
|
if (compound && !list_empty(page_deferred_list(page))) {
|
|
spin_lock(&from->deferred_split_queue.split_queue_lock);
|
|
list_del_init(page_deferred_list(page));
|
|
from->deferred_split_queue.split_queue_len--;
|
|
spin_unlock(&from->deferred_split_queue.split_queue_lock);
|
|
}
|
|
#endif
|
|
/*
|
|
* It is safe to change page->mem_cgroup here because the page
|
|
* is referenced, charged, and isolated - we can't race with
|
|
* uncharging, charging, migration, or LRU putback.
|
|
*/
|
|
|
|
/* caller should have done css_get */
|
|
page->mem_cgroup = to;
|
|
|
|
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
|
|
if (compound && list_empty(page_deferred_list(page))) {
|
|
spin_lock(&to->deferred_split_queue.split_queue_lock);
|
|
list_add_tail(page_deferred_list(page),
|
|
&to->deferred_split_queue.split_queue);
|
|
to->deferred_split_queue.split_queue_len++;
|
|
spin_unlock(&to->deferred_split_queue.split_queue_lock);
|
|
}
|
|
#endif
|
|
|
|
spin_unlock_irqrestore(&from->move_lock, flags);
|
|
|
|
ret = 0;
|
|
|
|
local_irq_disable();
|
|
mem_cgroup_charge_statistics(to, page, compound, nr_pages);
|
|
memcg_check_events(to, page);
|
|
mem_cgroup_charge_statistics(from, page, compound, -nr_pages);
|
|
memcg_check_events(from, page);
|
|
local_irq_enable();
|
|
out_unlock:
|
|
unlock_page(page);
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* get_mctgt_type - get target type of moving charge
|
|
* @vma: the vma the pte to be checked belongs
|
|
* @addr: the address corresponding to the pte to be checked
|
|
* @ptent: the pte to be checked
|
|
* @target: the pointer the target page or swap ent will be stored(can be NULL)
|
|
*
|
|
* Returns
|
|
* 0(MC_TARGET_NONE): if the pte is not a target for move charge.
|
|
* 1(MC_TARGET_PAGE): if the page corresponding to this pte is a target for
|
|
* move charge. if @target is not NULL, the page is stored in target->page
|
|
* with extra refcnt got(Callers should handle it).
|
|
* 2(MC_TARGET_SWAP): if the swap entry corresponding to this pte is a
|
|
* target for charge migration. if @target is not NULL, the entry is stored
|
|
* in target->ent.
|
|
* 3(MC_TARGET_DEVICE): like MC_TARGET_PAGE but page is MEMORY_DEVICE_PRIVATE
|
|
* (so ZONE_DEVICE page and thus not on the lru).
|
|
* For now we such page is charge like a regular page would be as for all
|
|
* intent and purposes it is just special memory taking the place of a
|
|
* regular page.
|
|
*
|
|
* See Documentations/vm/hmm.txt and include/linux/hmm.h
|
|
*
|
|
* Called with pte lock held.
|
|
*/
|
|
|
|
static enum mc_target_type get_mctgt_type(struct vm_area_struct *vma,
|
|
unsigned long addr, pte_t ptent, union mc_target *target)
|
|
{
|
|
struct page *page = NULL;
|
|
enum mc_target_type ret = MC_TARGET_NONE;
|
|
swp_entry_t ent = { .val = 0 };
|
|
|
|
if (pte_present(ptent))
|
|
page = mc_handle_present_pte(vma, addr, ptent);
|
|
else if (is_swap_pte(ptent))
|
|
page = mc_handle_swap_pte(vma, ptent, &ent);
|
|
else if (pte_none(ptent))
|
|
page = mc_handle_file_pte(vma, addr, ptent, &ent);
|
|
|
|
if (!page && !ent.val)
|
|
return ret;
|
|
if (page) {
|
|
/*
|
|
* Do only loose check w/o serialization.
|
|
* mem_cgroup_move_account() checks the page is valid or
|
|
* not under LRU exclusion.
|
|
*/
|
|
if (page->mem_cgroup == mc.from) {
|
|
ret = MC_TARGET_PAGE;
|
|
if (is_device_private_page(page))
|
|
ret = MC_TARGET_DEVICE;
|
|
if (target)
|
|
target->page = page;
|
|
}
|
|
if (!ret || !target)
|
|
put_page(page);
|
|
}
|
|
/*
|
|
* There is a swap entry and a page doesn't exist or isn't charged.
|
|
* But we cannot move a tail-page in a THP.
|
|
*/
|
|
if (ent.val && !ret && (!page || !PageTransCompound(page)) &&
|
|
mem_cgroup_id(mc.from) == lookup_swap_cgroup_id(ent)) {
|
|
ret = MC_TARGET_SWAP;
|
|
if (target)
|
|
target->ent = ent;
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
|
|
/*
|
|
* We don't consider PMD mapped swapping or file mapped pages because THP does
|
|
* not support them for now.
|
|
* Caller should make sure that pmd_trans_huge(pmd) is true.
|
|
*/
|
|
static enum mc_target_type get_mctgt_type_thp(struct vm_area_struct *vma,
|
|
unsigned long addr, pmd_t pmd, union mc_target *target)
|
|
{
|
|
struct page *page = NULL;
|
|
enum mc_target_type ret = MC_TARGET_NONE;
|
|
|
|
if (unlikely(is_swap_pmd(pmd))) {
|
|
VM_BUG_ON(thp_migration_supported() &&
|
|
!is_pmd_migration_entry(pmd));
|
|
return ret;
|
|
}
|
|
page = pmd_page(pmd);
|
|
VM_BUG_ON_PAGE(!page || !PageHead(page), page);
|
|
if (!(mc.flags & MOVE_ANON))
|
|
return ret;
|
|
if (page->mem_cgroup == mc.from) {
|
|
ret = MC_TARGET_PAGE;
|
|
if (target) {
|
|
get_page(page);
|
|
target->page = page;
|
|
}
|
|
}
|
|
return ret;
|
|
}
|
|
#else
|
|
static inline enum mc_target_type get_mctgt_type_thp(struct vm_area_struct *vma,
|
|
unsigned long addr, pmd_t pmd, union mc_target *target)
|
|
{
|
|
return MC_TARGET_NONE;
|
|
}
|
|
#endif
|
|
|
|
static int mem_cgroup_count_precharge_pte_range(pmd_t *pmd,
|
|
unsigned long addr, unsigned long end,
|
|
struct mm_walk *walk)
|
|
{
|
|
struct vm_area_struct *vma = walk->vma;
|
|
pte_t *pte;
|
|
spinlock_t *ptl;
|
|
|
|
ptl = pmd_trans_huge_lock(pmd, vma);
|
|
if (ptl) {
|
|
/*
|
|
* Note their can not be MC_TARGET_DEVICE for now as we do not
|
|
* support transparent huge page with MEMORY_DEVICE_PRIVATE but
|
|
* this might change.
|
|
*/
|
|
if (get_mctgt_type_thp(vma, addr, *pmd, NULL) == MC_TARGET_PAGE)
|
|
mc.precharge += HPAGE_PMD_NR;
|
|
spin_unlock(ptl);
|
|
return 0;
|
|
}
|
|
|
|
if (pmd_trans_unstable(pmd))
|
|
return 0;
|
|
pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
|
|
for (; addr != end; pte++, addr += PAGE_SIZE)
|
|
if (get_mctgt_type(vma, addr, *pte, NULL))
|
|
mc.precharge++; /* increment precharge temporarily */
|
|
pte_unmap_unlock(pte - 1, ptl);
|
|
cond_resched();
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct mm_walk_ops precharge_walk_ops = {
|
|
.pmd_entry = mem_cgroup_count_precharge_pte_range,
|
|
};
|
|
|
|
static unsigned long mem_cgroup_count_precharge(struct mm_struct *mm)
|
|
{
|
|
unsigned long precharge;
|
|
|
|
down_read(&mm->mmap_sem);
|
|
walk_page_range(mm, 0, mm->highest_vm_end, &precharge_walk_ops, NULL);
|
|
up_read(&mm->mmap_sem);
|
|
|
|
precharge = mc.precharge;
|
|
mc.precharge = 0;
|
|
|
|
return precharge;
|
|
}
|
|
|
|
static int mem_cgroup_precharge_mc(struct mm_struct *mm)
|
|
{
|
|
unsigned long precharge = mem_cgroup_count_precharge(mm);
|
|
|
|
VM_BUG_ON(mc.moving_task);
|
|
mc.moving_task = current;
|
|
return mem_cgroup_do_precharge(precharge);
|
|
}
|
|
|
|
/* cancels all extra charges on mc.from and mc.to, and wakes up all waiters. */
|
|
static void __mem_cgroup_clear_mc(void)
|
|
{
|
|
struct mem_cgroup *from = mc.from;
|
|
struct mem_cgroup *to = mc.to;
|
|
|
|
/* we must uncharge all the leftover precharges from mc.to */
|
|
if (mc.precharge) {
|
|
cancel_charge(mc.to, mc.precharge);
|
|
mc.precharge = 0;
|
|
}
|
|
/*
|
|
* we didn't uncharge from mc.from at mem_cgroup_move_account(), so
|
|
* we must uncharge here.
|
|
*/
|
|
if (mc.moved_charge) {
|
|
cancel_charge(mc.from, mc.moved_charge);
|
|
mc.moved_charge = 0;
|
|
}
|
|
/* we must fixup refcnts and charges */
|
|
if (mc.moved_swap) {
|
|
/* uncharge swap account from the old cgroup */
|
|
if (!mem_cgroup_is_root(mc.from))
|
|
page_counter_uncharge(&mc.from->memsw, mc.moved_swap);
|
|
|
|
mem_cgroup_id_put_many(mc.from, mc.moved_swap);
|
|
|
|
/*
|
|
* we charged both to->memory and to->memsw, so we
|
|
* should uncharge to->memory.
|
|
*/
|
|
if (!mem_cgroup_is_root(mc.to))
|
|
page_counter_uncharge(&mc.to->memory, mc.moved_swap);
|
|
|
|
mem_cgroup_id_get_many(mc.to, mc.moved_swap);
|
|
css_put_many(&mc.to->css, mc.moved_swap);
|
|
|
|
mc.moved_swap = 0;
|
|
}
|
|
memcg_oom_recover(from);
|
|
memcg_oom_recover(to);
|
|
wake_up_all(&mc.waitq);
|
|
}
|
|
|
|
static void mem_cgroup_clear_mc(void)
|
|
{
|
|
struct mm_struct *mm = mc.mm;
|
|
|
|
/*
|
|
* we must clear moving_task before waking up waiters at the end of
|
|
* task migration.
|
|
*/
|
|
mc.moving_task = NULL;
|
|
__mem_cgroup_clear_mc();
|
|
spin_lock(&mc.lock);
|
|
mc.from = NULL;
|
|
mc.to = NULL;
|
|
mc.mm = NULL;
|
|
spin_unlock(&mc.lock);
|
|
|
|
mmput(mm);
|
|
}
|
|
|
|
static int mem_cgroup_can_attach(struct cgroup_taskset *tset)
|
|
{
|
|
struct cgroup_subsys_state *css;
|
|
struct mem_cgroup *memcg = NULL; /* unneeded init to make gcc happy */
|
|
struct mem_cgroup *from;
|
|
struct task_struct *leader, *p;
|
|
struct mm_struct *mm;
|
|
unsigned long move_flags;
|
|
int ret = 0;
|
|
|
|
/* charge immigration isn't supported on the default hierarchy */
|
|
if (cgroup_subsys_on_dfl(memory_cgrp_subsys))
|
|
return 0;
|
|
|
|
/*
|
|
* Multi-process migrations only happen on the default hierarchy
|
|
* where charge immigration is not used. Perform charge
|
|
* immigration if @tset contains a leader and whine if there are
|
|
* multiple.
|
|
*/
|
|
p = NULL;
|
|
cgroup_taskset_for_each_leader(leader, css, tset) {
|
|
WARN_ON_ONCE(p);
|
|
p = leader;
|
|
memcg = mem_cgroup_from_css(css);
|
|
}
|
|
if (!p)
|
|
return 0;
|
|
|
|
/*
|
|
* We are now commited to this value whatever it is. Changes in this
|
|
* tunable will only affect upcoming migrations, not the current one.
|
|
* So we need to save it, and keep it going.
|
|
*/
|
|
move_flags = READ_ONCE(memcg->move_charge_at_immigrate);
|
|
if (!move_flags)
|
|
return 0;
|
|
|
|
from = mem_cgroup_from_task(p);
|
|
|
|
VM_BUG_ON(from == memcg);
|
|
|
|
mm = get_task_mm(p);
|
|
if (!mm)
|
|
return 0;
|
|
/* We move charges only when we move a owner of the mm */
|
|
if (mm->owner == p) {
|
|
VM_BUG_ON(mc.from);
|
|
VM_BUG_ON(mc.to);
|
|
VM_BUG_ON(mc.precharge);
|
|
VM_BUG_ON(mc.moved_charge);
|
|
VM_BUG_ON(mc.moved_swap);
|
|
|
|
spin_lock(&mc.lock);
|
|
mc.mm = mm;
|
|
mc.from = from;
|
|
mc.to = memcg;
|
|
mc.flags = move_flags;
|
|
spin_unlock(&mc.lock);
|
|
/* We set mc.moving_task later */
|
|
|
|
ret = mem_cgroup_precharge_mc(mm);
|
|
if (ret)
|
|
mem_cgroup_clear_mc();
|
|
} else {
|
|
mmput(mm);
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
static void mem_cgroup_cancel_attach(struct cgroup_taskset *tset)
|
|
{
|
|
if (mc.to)
|
|
mem_cgroup_clear_mc();
|
|
}
|
|
|
|
static int mem_cgroup_move_charge_pte_range(pmd_t *pmd,
|
|
unsigned long addr, unsigned long end,
|
|
struct mm_walk *walk)
|
|
{
|
|
int ret = 0;
|
|
struct vm_area_struct *vma = walk->vma;
|
|
pte_t *pte;
|
|
spinlock_t *ptl;
|
|
enum mc_target_type target_type;
|
|
union mc_target target;
|
|
struct page *page;
|
|
|
|
ptl = pmd_trans_huge_lock(pmd, vma);
|
|
if (ptl) {
|
|
if (mc.precharge < HPAGE_PMD_NR) {
|
|
spin_unlock(ptl);
|
|
return 0;
|
|
}
|
|
target_type = get_mctgt_type_thp(vma, addr, *pmd, &target);
|
|
if (target_type == MC_TARGET_PAGE) {
|
|
page = target.page;
|
|
if (!isolate_lru_page(page)) {
|
|
if (!mem_cgroup_move_account(page, true,
|
|
mc.from, mc.to)) {
|
|
mc.precharge -= HPAGE_PMD_NR;
|
|
mc.moved_charge += HPAGE_PMD_NR;
|
|
}
|
|
putback_lru_page(page);
|
|
}
|
|
put_page(page);
|
|
} else if (target_type == MC_TARGET_DEVICE) {
|
|
page = target.page;
|
|
if (!mem_cgroup_move_account(page, true,
|
|
mc.from, mc.to)) {
|
|
mc.precharge -= HPAGE_PMD_NR;
|
|
mc.moved_charge += HPAGE_PMD_NR;
|
|
}
|
|
put_page(page);
|
|
}
|
|
spin_unlock(ptl);
|
|
return 0;
|
|
}
|
|
|
|
if (pmd_trans_unstable(pmd))
|
|
return 0;
|
|
retry:
|
|
pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
|
|
for (; addr != end; addr += PAGE_SIZE) {
|
|
pte_t ptent = *(pte++);
|
|
bool device = false;
|
|
swp_entry_t ent;
|
|
|
|
if (!mc.precharge)
|
|
break;
|
|
|
|
switch (get_mctgt_type(vma, addr, ptent, &target)) {
|
|
case MC_TARGET_DEVICE:
|
|
device = true;
|
|
/* fall through */
|
|
case MC_TARGET_PAGE:
|
|
page = target.page;
|
|
/*
|
|
* We can have a part of the split pmd here. Moving it
|
|
* can be done but it would be too convoluted so simply
|
|
* ignore such a partial THP and keep it in original
|
|
* memcg. There should be somebody mapping the head.
|
|
*/
|
|
if (PageTransCompound(page))
|
|
goto put;
|
|
if (!device && isolate_lru_page(page))
|
|
goto put;
|
|
if (!mem_cgroup_move_account(page, false,
|
|
mc.from, mc.to)) {
|
|
mc.precharge--;
|
|
/* we uncharge from mc.from later. */
|
|
mc.moved_charge++;
|
|
}
|
|
if (!device)
|
|
putback_lru_page(page);
|
|
put: /* get_mctgt_type() gets the page */
|
|
put_page(page);
|
|
break;
|
|
case MC_TARGET_SWAP:
|
|
ent = target.ent;
|
|
if (!mem_cgroup_move_swap_account(ent, mc.from, mc.to)) {
|
|
mc.precharge--;
|
|
/* we fixup refcnts and charges later. */
|
|
mc.moved_swap++;
|
|
}
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
}
|
|
pte_unmap_unlock(pte - 1, ptl);
|
|
cond_resched();
|
|
|
|
if (addr != end) {
|
|
/*
|
|
* We have consumed all precharges we got in can_attach().
|
|
* We try charge one by one, but don't do any additional
|
|
* charges to mc.to if we have failed in charge once in attach()
|
|
* phase.
|
|
*/
|
|
ret = mem_cgroup_do_precharge(1);
|
|
if (!ret)
|
|
goto retry;
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static const struct mm_walk_ops charge_walk_ops = {
|
|
.pmd_entry = mem_cgroup_move_charge_pte_range,
|
|
};
|
|
|
|
static void mem_cgroup_move_charge(void)
|
|
{
|
|
lru_add_drain_all();
|
|
/*
|
|
* Signal lock_page_memcg() to take the memcg's move_lock
|
|
* while we're moving its pages to another memcg. Then wait
|
|
* for already started RCU-only updates to finish.
|
|
*/
|
|
atomic_inc(&mc.from->moving_account);
|
|
synchronize_rcu();
|
|
retry:
|
|
if (unlikely(!down_read_trylock(&mc.mm->mmap_sem))) {
|
|
/*
|
|
* Someone who are holding the mmap_sem might be waiting in
|
|
* waitq. So we cancel all extra charges, wake up all waiters,
|
|
* and retry. Because we cancel precharges, we might not be able
|
|
* to move enough charges, but moving charge is a best-effort
|
|
* feature anyway, so it wouldn't be a big problem.
|
|
*/
|
|
__mem_cgroup_clear_mc();
|
|
cond_resched();
|
|
goto retry;
|
|
}
|
|
/*
|
|
* When we have consumed all precharges and failed in doing
|
|
* additional charge, the page walk just aborts.
|
|
*/
|
|
walk_page_range(mc.mm, 0, mc.mm->highest_vm_end, &charge_walk_ops,
|
|
NULL);
|
|
|
|
up_read(&mc.mm->mmap_sem);
|
|
atomic_dec(&mc.from->moving_account);
|
|
}
|
|
|
|
static void mem_cgroup_move_task(void)
|
|
{
|
|
if (mc.to) {
|
|
mem_cgroup_move_charge();
|
|
mem_cgroup_clear_mc();
|
|
}
|
|
}
|
|
#else /* !CONFIG_MMU */
|
|
static int mem_cgroup_can_attach(struct cgroup_taskset *tset)
|
|
{
|
|
return 0;
|
|
}
|
|
static void mem_cgroup_cancel_attach(struct cgroup_taskset *tset)
|
|
{
|
|
}
|
|
static void mem_cgroup_move_task(void)
|
|
{
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* Cgroup retains root cgroups across [un]mount cycles making it necessary
|
|
* to verify whether we're attached to the default hierarchy on each mount
|
|
* attempt.
|
|
*/
|
|
static void mem_cgroup_bind(struct cgroup_subsys_state *root_css)
|
|
{
|
|
/*
|
|
* use_hierarchy is forced on the default hierarchy. cgroup core
|
|
* guarantees that @root doesn't have any children, so turning it
|
|
* on for the root memcg is enough.
|
|
*/
|
|
if (cgroup_subsys_on_dfl(memory_cgrp_subsys))
|
|
root_mem_cgroup->use_hierarchy = true;
|
|
else
|
|
root_mem_cgroup->use_hierarchy = false;
|
|
}
|
|
|
|
static int seq_puts_memcg_tunable(struct seq_file *m, unsigned long value)
|
|
{
|
|
if (value == PAGE_COUNTER_MAX)
|
|
seq_puts(m, "max\n");
|
|
else
|
|
seq_printf(m, "%llu\n", (u64)value * PAGE_SIZE);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static u64 memory_current_read(struct cgroup_subsys_state *css,
|
|
struct cftype *cft)
|
|
{
|
|
struct mem_cgroup *memcg = mem_cgroup_from_css(css);
|
|
|
|
return (u64)page_counter_read(&memcg->memory) * PAGE_SIZE;
|
|
}
|
|
|
|
static int memory_min_show(struct seq_file *m, void *v)
|
|
{
|
|
return seq_puts_memcg_tunable(m,
|
|
READ_ONCE(mem_cgroup_from_seq(m)->memory.min));
|
|
}
|
|
|
|
static ssize_t memory_min_write(struct kernfs_open_file *of,
|
|
char *buf, size_t nbytes, loff_t off)
|
|
{
|
|
struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of));
|
|
unsigned long min;
|
|
int err;
|
|
|
|
buf = strstrip(buf);
|
|
err = page_counter_memparse(buf, "max", &min);
|
|
if (err)
|
|
return err;
|
|
|
|
page_counter_set_min(&memcg->memory, min);
|
|
|
|
return nbytes;
|
|
}
|
|
|
|
static int memory_low_show(struct seq_file *m, void *v)
|
|
{
|
|
return seq_puts_memcg_tunable(m,
|
|
READ_ONCE(mem_cgroup_from_seq(m)->memory.low));
|
|
}
|
|
|
|
static ssize_t memory_low_write(struct kernfs_open_file *of,
|
|
char *buf, size_t nbytes, loff_t off)
|
|
{
|
|
struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of));
|
|
unsigned long low;
|
|
int err;
|
|
|
|
buf = strstrip(buf);
|
|
err = page_counter_memparse(buf, "max", &low);
|
|
if (err)
|
|
return err;
|
|
|
|
page_counter_set_low(&memcg->memory, low);
|
|
|
|
return nbytes;
|
|
}
|
|
|
|
static int memory_high_show(struct seq_file *m, void *v)
|
|
{
|
|
return seq_puts_memcg_tunable(m, READ_ONCE(mem_cgroup_from_seq(m)->high));
|
|
}
|
|
|
|
static ssize_t memory_high_write(struct kernfs_open_file *of,
|
|
char *buf, size_t nbytes, loff_t off)
|
|
{
|
|
struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of));
|
|
unsigned long nr_pages;
|
|
unsigned long high;
|
|
int err;
|
|
|
|
buf = strstrip(buf);
|
|
err = page_counter_memparse(buf, "max", &high);
|
|
if (err)
|
|
return err;
|
|
|
|
memcg->high = high;
|
|
|
|
nr_pages = page_counter_read(&memcg->memory);
|
|
if (nr_pages > high)
|
|
try_to_free_mem_cgroup_pages(memcg, nr_pages - high,
|
|
GFP_KERNEL, true);
|
|
|
|
memcg_wb_domain_size_changed(memcg);
|
|
return nbytes;
|
|
}
|
|
|
|
static int memory_max_show(struct seq_file *m, void *v)
|
|
{
|
|
return seq_puts_memcg_tunable(m,
|
|
READ_ONCE(mem_cgroup_from_seq(m)->memory.max));
|
|
}
|
|
|
|
static ssize_t memory_max_write(struct kernfs_open_file *of,
|
|
char *buf, size_t nbytes, loff_t off)
|
|
{
|
|
struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of));
|
|
unsigned int nr_reclaims = MEM_CGROUP_RECLAIM_RETRIES;
|
|
bool drained = false;
|
|
unsigned long max;
|
|
int err;
|
|
|
|
buf = strstrip(buf);
|
|
err = page_counter_memparse(buf, "max", &max);
|
|
if (err)
|
|
return err;
|
|
|
|
xchg(&memcg->memory.max, max);
|
|
|
|
for (;;) {
|
|
unsigned long nr_pages = page_counter_read(&memcg->memory);
|
|
|
|
if (nr_pages <= max)
|
|
break;
|
|
|
|
if (signal_pending(current)) {
|
|
err = -EINTR;
|
|
break;
|
|
}
|
|
|
|
if (!drained) {
|
|
drain_all_stock(memcg);
|
|
drained = true;
|
|
continue;
|
|
}
|
|
|
|
if (nr_reclaims) {
|
|
if (!try_to_free_mem_cgroup_pages(memcg, nr_pages - max,
|
|
GFP_KERNEL, true))
|
|
nr_reclaims--;
|
|
continue;
|
|
}
|
|
|
|
memcg_memory_event(memcg, MEMCG_OOM);
|
|
if (!mem_cgroup_out_of_memory(memcg, GFP_KERNEL, 0))
|
|
break;
|
|
}
|
|
|
|
memcg_wb_domain_size_changed(memcg);
|
|
return nbytes;
|
|
}
|
|
|
|
static void __memory_events_show(struct seq_file *m, atomic_long_t *events)
|
|
{
|
|
seq_printf(m, "low %lu\n", atomic_long_read(&events[MEMCG_LOW]));
|
|
seq_printf(m, "high %lu\n", atomic_long_read(&events[MEMCG_HIGH]));
|
|
seq_printf(m, "max %lu\n", atomic_long_read(&events[MEMCG_MAX]));
|
|
seq_printf(m, "oom %lu\n", atomic_long_read(&events[MEMCG_OOM]));
|
|
seq_printf(m, "oom_kill %lu\n",
|
|
atomic_long_read(&events[MEMCG_OOM_KILL]));
|
|
}
|
|
|
|
static int memory_events_show(struct seq_file *m, void *v)
|
|
{
|
|
struct mem_cgroup *memcg = mem_cgroup_from_seq(m);
|
|
|
|
__memory_events_show(m, memcg->memory_events);
|
|
return 0;
|
|
}
|
|
|
|
static int memory_events_local_show(struct seq_file *m, void *v)
|
|
{
|
|
struct mem_cgroup *memcg = mem_cgroup_from_seq(m);
|
|
|
|
__memory_events_show(m, memcg->memory_events_local);
|
|
return 0;
|
|
}
|
|
|
|
static int memory_stat_show(struct seq_file *m, void *v)
|
|
{
|
|
struct mem_cgroup *memcg = mem_cgroup_from_seq(m);
|
|
char *buf;
|
|
|
|
buf = memory_stat_format(memcg);
|
|
if (!buf)
|
|
return -ENOMEM;
|
|
seq_puts(m, buf);
|
|
kfree(buf);
|
|
return 0;
|
|
}
|
|
|
|
static int memory_oom_group_show(struct seq_file *m, void *v)
|
|
{
|
|
struct mem_cgroup *memcg = mem_cgroup_from_seq(m);
|
|
|
|
seq_printf(m, "%d\n", memcg->oom_group);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static ssize_t memory_oom_group_write(struct kernfs_open_file *of,
|
|
char *buf, size_t nbytes, loff_t off)
|
|
{
|
|
struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of));
|
|
int ret, oom_group;
|
|
|
|
buf = strstrip(buf);
|
|
if (!buf)
|
|
return -EINVAL;
|
|
|
|
ret = kstrtoint(buf, 0, &oom_group);
|
|
if (ret)
|
|
return ret;
|
|
|
|
if (oom_group != 0 && oom_group != 1)
|
|
return -EINVAL;
|
|
|
|
memcg->oom_group = oom_group;
|
|
|
|
return nbytes;
|
|
}
|
|
|
|
static struct cftype memory_files[] = {
|
|
{
|
|
.name = "current",
|
|
.flags = CFTYPE_NOT_ON_ROOT,
|
|
.read_u64 = memory_current_read,
|
|
},
|
|
{
|
|
.name = "min",
|
|
.flags = CFTYPE_NOT_ON_ROOT,
|
|
.seq_show = memory_min_show,
|
|
.write = memory_min_write,
|
|
},
|
|
{
|
|
.name = "low",
|
|
.flags = CFTYPE_NOT_ON_ROOT,
|
|
.seq_show = memory_low_show,
|
|
.write = memory_low_write,
|
|
},
|
|
{
|
|
.name = "high",
|
|
.flags = CFTYPE_NOT_ON_ROOT,
|
|
.seq_show = memory_high_show,
|
|
.write = memory_high_write,
|
|
},
|
|
{
|
|
.name = "max",
|
|
.flags = CFTYPE_NOT_ON_ROOT,
|
|
.seq_show = memory_max_show,
|
|
.write = memory_max_write,
|
|
},
|
|
{
|
|
.name = "events",
|
|
.flags = CFTYPE_NOT_ON_ROOT,
|
|
.file_offset = offsetof(struct mem_cgroup, events_file),
|
|
.seq_show = memory_events_show,
|
|
},
|
|
{
|
|
.name = "events.local",
|
|
.flags = CFTYPE_NOT_ON_ROOT,
|
|
.file_offset = offsetof(struct mem_cgroup, events_local_file),
|
|
.seq_show = memory_events_local_show,
|
|
},
|
|
{
|
|
.name = "stat",
|
|
.flags = CFTYPE_NOT_ON_ROOT,
|
|
.seq_show = memory_stat_show,
|
|
},
|
|
{
|
|
.name = "oom.group",
|
|
.flags = CFTYPE_NOT_ON_ROOT | CFTYPE_NS_DELEGATABLE,
|
|
.seq_show = memory_oom_group_show,
|
|
.write = memory_oom_group_write,
|
|
},
|
|
{ } /* terminate */
|
|
};
|
|
|
|
struct cgroup_subsys memory_cgrp_subsys = {
|
|
.css_alloc = mem_cgroup_css_alloc,
|
|
.css_online = mem_cgroup_css_online,
|
|
.css_offline = mem_cgroup_css_offline,
|
|
.css_released = mem_cgroup_css_released,
|
|
.css_free = mem_cgroup_css_free,
|
|
.css_reset = mem_cgroup_css_reset,
|
|
.can_attach = mem_cgroup_can_attach,
|
|
.cancel_attach = mem_cgroup_cancel_attach,
|
|
.post_attach = mem_cgroup_move_task,
|
|
.bind = mem_cgroup_bind,
|
|
.dfl_cftypes = memory_files,
|
|
.legacy_cftypes = mem_cgroup_legacy_files,
|
|
.early_init = 0,
|
|
};
|
|
|
|
/**
|
|
* mem_cgroup_protected - check if memory consumption is in the normal range
|
|
* @root: the top ancestor of the sub-tree being checked
|
|
* @memcg: the memory cgroup to check
|
|
*
|
|
* WARNING: This function is not stateless! It can only be used as part
|
|
* of a top-down tree iteration, not for isolated queries.
|
|
*
|
|
* Returns one of the following:
|
|
* MEMCG_PROT_NONE: cgroup memory is not protected
|
|
* MEMCG_PROT_LOW: cgroup memory is protected as long there is
|
|
* an unprotected supply of reclaimable memory from other cgroups.
|
|
* MEMCG_PROT_MIN: cgroup memory is protected
|
|
*
|
|
* @root is exclusive; it is never protected when looked at directly
|
|
*
|
|
* To provide a proper hierarchical behavior, effective memory.min/low values
|
|
* are used. Below is the description of how effective memory.low is calculated.
|
|
* Effective memory.min values is calculated in the same way.
|
|
*
|
|
* Effective memory.low is always equal or less than the original memory.low.
|
|
* If there is no memory.low overcommittment (which is always true for
|
|
* top-level memory cgroups), these two values are equal.
|
|
* Otherwise, it's a part of parent's effective memory.low,
|
|
* calculated as a cgroup's memory.low usage divided by sum of sibling's
|
|
* memory.low usages, where memory.low usage is the size of actually
|
|
* protected memory.
|
|
*
|
|
* low_usage
|
|
* elow = min( memory.low, parent->elow * ------------------ ),
|
|
* siblings_low_usage
|
|
*
|
|
* | memory.current, if memory.current < memory.low
|
|
* low_usage = |
|
|
* | 0, otherwise.
|
|
*
|
|
*
|
|
* Such definition of the effective memory.low provides the expected
|
|
* hierarchical behavior: parent's memory.low value is limiting
|
|
* children, unprotected memory is reclaimed first and cgroups,
|
|
* which are not using their guarantee do not affect actual memory
|
|
* distribution.
|
|
*
|
|
* For example, if there are memcgs A, A/B, A/C, A/D and A/E:
|
|
*
|
|
* A A/memory.low = 2G, A/memory.current = 6G
|
|
* //\\
|
|
* BC DE B/memory.low = 3G B/memory.current = 2G
|
|
* C/memory.low = 1G C/memory.current = 2G
|
|
* D/memory.low = 0 D/memory.current = 2G
|
|
* E/memory.low = 10G E/memory.current = 0
|
|
*
|
|
* and the memory pressure is applied, the following memory distribution
|
|
* is expected (approximately):
|
|
*
|
|
* A/memory.current = 2G
|
|
*
|
|
* B/memory.current = 1.3G
|
|
* C/memory.current = 0.6G
|
|
* D/memory.current = 0
|
|
* E/memory.current = 0
|
|
*
|
|
* These calculations require constant tracking of the actual low usages
|
|
* (see propagate_protected_usage()), as well as recursive calculation of
|
|
* effective memory.low values. But as we do call mem_cgroup_protected()
|
|
* path for each memory cgroup top-down from the reclaim,
|
|
* it's possible to optimize this part, and save calculated elow
|
|
* for next usage. This part is intentionally racy, but it's ok,
|
|
* as memory.low is a best-effort mechanism.
|
|
*/
|
|
enum mem_cgroup_protection mem_cgroup_protected(struct mem_cgroup *root,
|
|
struct mem_cgroup *memcg)
|
|
{
|
|
struct mem_cgroup *parent;
|
|
unsigned long emin, parent_emin;
|
|
unsigned long elow, parent_elow;
|
|
unsigned long usage;
|
|
|
|
if (mem_cgroup_disabled())
|
|
return MEMCG_PROT_NONE;
|
|
|
|
if (!root)
|
|
root = root_mem_cgroup;
|
|
if (memcg == root)
|
|
return MEMCG_PROT_NONE;
|
|
|
|
usage = page_counter_read(&memcg->memory);
|
|
if (!usage)
|
|
return MEMCG_PROT_NONE;
|
|
|
|
emin = memcg->memory.min;
|
|
elow = memcg->memory.low;
|
|
|
|
parent = parent_mem_cgroup(memcg);
|
|
/* No parent means a non-hierarchical mode on v1 memcg */
|
|
if (!parent)
|
|
return MEMCG_PROT_NONE;
|
|
|
|
if (parent == root)
|
|
goto exit;
|
|
|
|
parent_emin = READ_ONCE(parent->memory.emin);
|
|
emin = min(emin, parent_emin);
|
|
if (emin && parent_emin) {
|
|
unsigned long min_usage, siblings_min_usage;
|
|
|
|
min_usage = min(usage, memcg->memory.min);
|
|
siblings_min_usage = atomic_long_read(
|
|
&parent->memory.children_min_usage);
|
|
|
|
if (min_usage && siblings_min_usage)
|
|
emin = min(emin, parent_emin * min_usage /
|
|
siblings_min_usage);
|
|
}
|
|
|
|
parent_elow = READ_ONCE(parent->memory.elow);
|
|
elow = min(elow, parent_elow);
|
|
if (elow && parent_elow) {
|
|
unsigned long low_usage, siblings_low_usage;
|
|
|
|
low_usage = min(usage, memcg->memory.low);
|
|
siblings_low_usage = atomic_long_read(
|
|
&parent->memory.children_low_usage);
|
|
|
|
if (low_usage && siblings_low_usage)
|
|
elow = min(elow, parent_elow * low_usage /
|
|
siblings_low_usage);
|
|
}
|
|
|
|
exit:
|
|
memcg->memory.emin = emin;
|
|
memcg->memory.elow = elow;
|
|
|
|
if (usage <= emin)
|
|
return MEMCG_PROT_MIN;
|
|
else if (usage <= elow)
|
|
return MEMCG_PROT_LOW;
|
|
else
|
|
return MEMCG_PROT_NONE;
|
|
}
|
|
|
|
/**
|
|
* mem_cgroup_try_charge - try charging a page
|
|
* @page: page to charge
|
|
* @mm: mm context of the victim
|
|
* @gfp_mask: reclaim mode
|
|
* @memcgp: charged memcg return
|
|
* @compound: charge the page as compound or small page
|
|
*
|
|
* Try to charge @page to the memcg that @mm belongs to, reclaiming
|
|
* pages according to @gfp_mask if necessary.
|
|
*
|
|
* Returns 0 on success, with *@memcgp pointing to the charged memcg.
|
|
* Otherwise, an error code is returned.
|
|
*
|
|
* After page->mapping has been set up, the caller must finalize the
|
|
* charge with mem_cgroup_commit_charge(). Or abort the transaction
|
|
* with mem_cgroup_cancel_charge() in case page instantiation fails.
|
|
*/
|
|
int mem_cgroup_try_charge(struct page *page, struct mm_struct *mm,
|
|
gfp_t gfp_mask, struct mem_cgroup **memcgp,
|
|
bool compound)
|
|
{
|
|
struct mem_cgroup *memcg = NULL;
|
|
unsigned int nr_pages = compound ? hpage_nr_pages(page) : 1;
|
|
int ret = 0;
|
|
|
|
if (mem_cgroup_disabled())
|
|
goto out;
|
|
|
|
if (PageSwapCache(page)) {
|
|
/*
|
|
* Every swap fault against a single page tries to charge the
|
|
* page, bail as early as possible. shmem_unuse() encounters
|
|
* already charged pages, too. The USED bit is protected by
|
|
* the page lock, which serializes swap cache removal, which
|
|
* in turn serializes uncharging.
|
|
*/
|
|
VM_BUG_ON_PAGE(!PageLocked(page), page);
|
|
if (compound_head(page)->mem_cgroup)
|
|
goto out;
|
|
|
|
if (do_swap_account) {
|
|
swp_entry_t ent = { .val = page_private(page), };
|
|
unsigned short id = lookup_swap_cgroup_id(ent);
|
|
|
|
rcu_read_lock();
|
|
memcg = mem_cgroup_from_id(id);
|
|
if (memcg && !css_tryget_online(&memcg->css))
|
|
memcg = NULL;
|
|
rcu_read_unlock();
|
|
}
|
|
}
|
|
|
|
if (!memcg)
|
|
memcg = get_mem_cgroup_from_mm(mm);
|
|
|
|
ret = try_charge(memcg, gfp_mask, nr_pages);
|
|
|
|
css_put(&memcg->css);
|
|
out:
|
|
*memcgp = memcg;
|
|
return ret;
|
|
}
|
|
|
|
int mem_cgroup_try_charge_delay(struct page *page, struct mm_struct *mm,
|
|
gfp_t gfp_mask, struct mem_cgroup **memcgp,
|
|
bool compound)
|
|
{
|
|
struct mem_cgroup *memcg;
|
|
int ret;
|
|
|
|
ret = mem_cgroup_try_charge(page, mm, gfp_mask, memcgp, compound);
|
|
memcg = *memcgp;
|
|
mem_cgroup_throttle_swaprate(memcg, page_to_nid(page), gfp_mask);
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* mem_cgroup_commit_charge - commit a page charge
|
|
* @page: page to charge
|
|
* @memcg: memcg to charge the page to
|
|
* @lrucare: page might be on LRU already
|
|
* @compound: charge the page as compound or small page
|
|
*
|
|
* Finalize a charge transaction started by mem_cgroup_try_charge(),
|
|
* after page->mapping has been set up. This must happen atomically
|
|
* as part of the page instantiation, i.e. under the page table lock
|
|
* for anonymous pages, under the page lock for page and swap cache.
|
|
*
|
|
* In addition, the page must not be on the LRU during the commit, to
|
|
* prevent racing with task migration. If it might be, use @lrucare.
|
|
*
|
|
* Use mem_cgroup_cancel_charge() to cancel the transaction instead.
|
|
*/
|
|
void mem_cgroup_commit_charge(struct page *page, struct mem_cgroup *memcg,
|
|
bool lrucare, bool compound)
|
|
{
|
|
unsigned int nr_pages = compound ? hpage_nr_pages(page) : 1;
|
|
|
|
VM_BUG_ON_PAGE(!page->mapping, page);
|
|
VM_BUG_ON_PAGE(PageLRU(page) && !lrucare, page);
|
|
|
|
if (mem_cgroup_disabled())
|
|
return;
|
|
/*
|
|
* Swap faults will attempt to charge the same page multiple
|
|
* times. But reuse_swap_page() might have removed the page
|
|
* from swapcache already, so we can't check PageSwapCache().
|
|
*/
|
|
if (!memcg)
|
|
return;
|
|
|
|
commit_charge(page, memcg, lrucare);
|
|
|
|
local_irq_disable();
|
|
mem_cgroup_charge_statistics(memcg, page, compound, nr_pages);
|
|
memcg_check_events(memcg, page);
|
|
local_irq_enable();
|
|
|
|
if (do_memsw_account() && PageSwapCache(page)) {
|
|
swp_entry_t entry = { .val = page_private(page) };
|
|
/*
|
|
* The swap entry might not get freed for a long time,
|
|
* let's not wait for it. The page already received a
|
|
* memory+swap charge, drop the swap entry duplicate.
|
|
*/
|
|
mem_cgroup_uncharge_swap(entry, nr_pages);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* mem_cgroup_cancel_charge - cancel a page charge
|
|
* @page: page to charge
|
|
* @memcg: memcg to charge the page to
|
|
* @compound: charge the page as compound or small page
|
|
*
|
|
* Cancel a charge transaction started by mem_cgroup_try_charge().
|
|
*/
|
|
void mem_cgroup_cancel_charge(struct page *page, struct mem_cgroup *memcg,
|
|
bool compound)
|
|
{
|
|
unsigned int nr_pages = compound ? hpage_nr_pages(page) : 1;
|
|
|
|
if (mem_cgroup_disabled())
|
|
return;
|
|
/*
|
|
* Swap faults will attempt to charge the same page multiple
|
|
* times. But reuse_swap_page() might have removed the page
|
|
* from swapcache already, so we can't check PageSwapCache().
|
|
*/
|
|
if (!memcg)
|
|
return;
|
|
|
|
cancel_charge(memcg, nr_pages);
|
|
}
|
|
|
|
struct uncharge_gather {
|
|
struct mem_cgroup *memcg;
|
|
unsigned long pgpgout;
|
|
unsigned long nr_anon;
|
|
unsigned long nr_file;
|
|
unsigned long nr_kmem;
|
|
unsigned long nr_huge;
|
|
unsigned long nr_shmem;
|
|
struct page *dummy_page;
|
|
};
|
|
|
|
static inline void uncharge_gather_clear(struct uncharge_gather *ug)
|
|
{
|
|
memset(ug, 0, sizeof(*ug));
|
|
}
|
|
|
|
static void uncharge_batch(const struct uncharge_gather *ug)
|
|
{
|
|
unsigned long nr_pages = ug->nr_anon + ug->nr_file + ug->nr_kmem;
|
|
unsigned long flags;
|
|
|
|
if (!mem_cgroup_is_root(ug->memcg)) {
|
|
page_counter_uncharge(&ug->memcg->memory, nr_pages);
|
|
if (do_memsw_account())
|
|
page_counter_uncharge(&ug->memcg->memsw, nr_pages);
|
|
if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) && ug->nr_kmem)
|
|
page_counter_uncharge(&ug->memcg->kmem, ug->nr_kmem);
|
|
memcg_oom_recover(ug->memcg);
|
|
}
|
|
|
|
local_irq_save(flags);
|
|
__mod_memcg_state(ug->memcg, MEMCG_RSS, -ug->nr_anon);
|
|
__mod_memcg_state(ug->memcg, MEMCG_CACHE, -ug->nr_file);
|
|
__mod_memcg_state(ug->memcg, MEMCG_RSS_HUGE, -ug->nr_huge);
|
|
__mod_memcg_state(ug->memcg, NR_SHMEM, -ug->nr_shmem);
|
|
__count_memcg_events(ug->memcg, PGPGOUT, ug->pgpgout);
|
|
__this_cpu_add(ug->memcg->vmstats_percpu->nr_page_events, nr_pages);
|
|
memcg_check_events(ug->memcg, ug->dummy_page);
|
|
local_irq_restore(flags);
|
|
|
|
if (!mem_cgroup_is_root(ug->memcg))
|
|
css_put_many(&ug->memcg->css, nr_pages);
|
|
}
|
|
|
|
static void uncharge_page(struct page *page, struct uncharge_gather *ug)
|
|
{
|
|
VM_BUG_ON_PAGE(PageLRU(page), page);
|
|
VM_BUG_ON_PAGE(page_count(page) && !is_zone_device_page(page) &&
|
|
!PageHWPoison(page) , page);
|
|
|
|
if (!page->mem_cgroup)
|
|
return;
|
|
|
|
/*
|
|
* Nobody should be changing or seriously looking at
|
|
* page->mem_cgroup at this point, we have fully
|
|
* exclusive access to the page.
|
|
*/
|
|
|
|
if (ug->memcg != page->mem_cgroup) {
|
|
if (ug->memcg) {
|
|
uncharge_batch(ug);
|
|
uncharge_gather_clear(ug);
|
|
}
|
|
ug->memcg = page->mem_cgroup;
|
|
}
|
|
|
|
if (!PageKmemcg(page)) {
|
|
unsigned int nr_pages = 1;
|
|
|
|
if (PageTransHuge(page)) {
|
|
nr_pages = compound_nr(page);
|
|
ug->nr_huge += nr_pages;
|
|
}
|
|
if (PageAnon(page))
|
|
ug->nr_anon += nr_pages;
|
|
else {
|
|
ug->nr_file += nr_pages;
|
|
if (PageSwapBacked(page))
|
|
ug->nr_shmem += nr_pages;
|
|
}
|
|
ug->pgpgout++;
|
|
} else {
|
|
ug->nr_kmem += compound_nr(page);
|
|
__ClearPageKmemcg(page);
|
|
}
|
|
|
|
ug->dummy_page = page;
|
|
page->mem_cgroup = NULL;
|
|
}
|
|
|
|
static void uncharge_list(struct list_head *page_list)
|
|
{
|
|
struct uncharge_gather ug;
|
|
struct list_head *next;
|
|
|
|
uncharge_gather_clear(&ug);
|
|
|
|
/*
|
|
* Note that the list can be a single page->lru; hence the
|
|
* do-while loop instead of a simple list_for_each_entry().
|
|
*/
|
|
next = page_list->next;
|
|
do {
|
|
struct page *page;
|
|
|
|
page = list_entry(next, struct page, lru);
|
|
next = page->lru.next;
|
|
|
|
uncharge_page(page, &ug);
|
|
} while (next != page_list);
|
|
|
|
if (ug.memcg)
|
|
uncharge_batch(&ug);
|
|
}
|
|
|
|
/**
|
|
* mem_cgroup_uncharge - uncharge a page
|
|
* @page: page to uncharge
|
|
*
|
|
* Uncharge a page previously charged with mem_cgroup_try_charge() and
|
|
* mem_cgroup_commit_charge().
|
|
*/
|
|
void mem_cgroup_uncharge(struct page *page)
|
|
{
|
|
struct uncharge_gather ug;
|
|
|
|
if (mem_cgroup_disabled())
|
|
return;
|
|
|
|
/* Don't touch page->lru of any random page, pre-check: */
|
|
if (!page->mem_cgroup)
|
|
return;
|
|
|
|
uncharge_gather_clear(&ug);
|
|
uncharge_page(page, &ug);
|
|
uncharge_batch(&ug);
|
|
}
|
|
|
|
/**
|
|
* mem_cgroup_uncharge_list - uncharge a list of page
|
|
* @page_list: list of pages to uncharge
|
|
*
|
|
* Uncharge a list of pages previously charged with
|
|
* mem_cgroup_try_charge() and mem_cgroup_commit_charge().
|
|
*/
|
|
void mem_cgroup_uncharge_list(struct list_head *page_list)
|
|
{
|
|
if (mem_cgroup_disabled())
|
|
return;
|
|
|
|
if (!list_empty(page_list))
|
|
uncharge_list(page_list);
|
|
}
|
|
|
|
/**
|
|
* mem_cgroup_migrate - charge a page's replacement
|
|
* @oldpage: currently circulating page
|
|
* @newpage: replacement page
|
|
*
|
|
* Charge @newpage as a replacement page for @oldpage. @oldpage will
|
|
* be uncharged upon free.
|
|
*
|
|
* Both pages must be locked, @newpage->mapping must be set up.
|
|
*/
|
|
void mem_cgroup_migrate(struct page *oldpage, struct page *newpage)
|
|
{
|
|
struct mem_cgroup *memcg;
|
|
unsigned int nr_pages;
|
|
bool compound;
|
|
unsigned long flags;
|
|
|
|
VM_BUG_ON_PAGE(!PageLocked(oldpage), oldpage);
|
|
VM_BUG_ON_PAGE(!PageLocked(newpage), newpage);
|
|
VM_BUG_ON_PAGE(PageAnon(oldpage) != PageAnon(newpage), newpage);
|
|
VM_BUG_ON_PAGE(PageTransHuge(oldpage) != PageTransHuge(newpage),
|
|
newpage);
|
|
|
|
if (mem_cgroup_disabled())
|
|
return;
|
|
|
|
/* Page cache replacement: new page already charged? */
|
|
if (newpage->mem_cgroup)
|
|
return;
|
|
|
|
/* Swapcache readahead pages can get replaced before being charged */
|
|
memcg = oldpage->mem_cgroup;
|
|
if (!memcg)
|
|
return;
|
|
|
|
/* Force-charge the new page. The old one will be freed soon */
|
|
compound = PageTransHuge(newpage);
|
|
nr_pages = compound ? hpage_nr_pages(newpage) : 1;
|
|
|
|
page_counter_charge(&memcg->memory, nr_pages);
|
|
if (do_memsw_account())
|
|
page_counter_charge(&memcg->memsw, nr_pages);
|
|
css_get_many(&memcg->css, nr_pages);
|
|
|
|
commit_charge(newpage, memcg, false);
|
|
|
|
local_irq_save(flags);
|
|
mem_cgroup_charge_statistics(memcg, newpage, compound, nr_pages);
|
|
memcg_check_events(memcg, newpage);
|
|
local_irq_restore(flags);
|
|
}
|
|
|
|
DEFINE_STATIC_KEY_FALSE(memcg_sockets_enabled_key);
|
|
EXPORT_SYMBOL(memcg_sockets_enabled_key);
|
|
|
|
void mem_cgroup_sk_alloc(struct sock *sk)
|
|
{
|
|
struct mem_cgroup *memcg;
|
|
|
|
if (!mem_cgroup_sockets_enabled)
|
|
return;
|
|
|
|
/*
|
|
* Socket cloning can throw us here with sk_memcg already
|
|
* filled. It won't however, necessarily happen from
|
|
* process context. So the test for root memcg given
|
|
* the current task's memcg won't help us in this case.
|
|
*
|
|
* Respecting the original socket's memcg is a better
|
|
* decision in this case.
|
|
*/
|
|
if (sk->sk_memcg) {
|
|
css_get(&sk->sk_memcg->css);
|
|
return;
|
|
}
|
|
|
|
rcu_read_lock();
|
|
memcg = mem_cgroup_from_task(current);
|
|
if (memcg == root_mem_cgroup)
|
|
goto out;
|
|
if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) && !memcg->tcpmem_active)
|
|
goto out;
|
|
if (css_tryget_online(&memcg->css))
|
|
sk->sk_memcg = memcg;
|
|
out:
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
void mem_cgroup_sk_free(struct sock *sk)
|
|
{
|
|
if (sk->sk_memcg)
|
|
css_put(&sk->sk_memcg->css);
|
|
}
|
|
|
|
/**
|
|
* mem_cgroup_charge_skmem - charge socket memory
|
|
* @memcg: memcg to charge
|
|
* @nr_pages: number of pages to charge
|
|
*
|
|
* Charges @nr_pages to @memcg. Returns %true if the charge fit within
|
|
* @memcg's configured limit, %false if the charge had to be forced.
|
|
*/
|
|
bool mem_cgroup_charge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages)
|
|
{
|
|
gfp_t gfp_mask = GFP_KERNEL;
|
|
|
|
if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) {
|
|
struct page_counter *fail;
|
|
|
|
if (page_counter_try_charge(&memcg->tcpmem, nr_pages, &fail)) {
|
|
memcg->tcpmem_pressure = 0;
|
|
return true;
|
|
}
|
|
page_counter_charge(&memcg->tcpmem, nr_pages);
|
|
memcg->tcpmem_pressure = 1;
|
|
return false;
|
|
}
|
|
|
|
/* Don't block in the packet receive path */
|
|
if (in_softirq())
|
|
gfp_mask = GFP_NOWAIT;
|
|
|
|
mod_memcg_state(memcg, MEMCG_SOCK, nr_pages);
|
|
|
|
if (try_charge(memcg, gfp_mask, nr_pages) == 0)
|
|
return true;
|
|
|
|
try_charge(memcg, gfp_mask|__GFP_NOFAIL, nr_pages);
|
|
return false;
|
|
}
|
|
|
|
/**
|
|
* mem_cgroup_uncharge_skmem - uncharge socket memory
|
|
* @memcg: memcg to uncharge
|
|
* @nr_pages: number of pages to uncharge
|
|
*/
|
|
void mem_cgroup_uncharge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages)
|
|
{
|
|
if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) {
|
|
page_counter_uncharge(&memcg->tcpmem, nr_pages);
|
|
return;
|
|
}
|
|
|
|
mod_memcg_state(memcg, MEMCG_SOCK, -nr_pages);
|
|
|
|
refill_stock(memcg, nr_pages);
|
|
}
|
|
|
|
static int __init cgroup_memory(char *s)
|
|
{
|
|
char *token;
|
|
|
|
while ((token = strsep(&s, ",")) != NULL) {
|
|
if (!*token)
|
|
continue;
|
|
if (!strcmp(token, "nosocket"))
|
|
cgroup_memory_nosocket = true;
|
|
if (!strcmp(token, "nokmem"))
|
|
cgroup_memory_nokmem = true;
|
|
}
|
|
return 0;
|
|
}
|
|
__setup("cgroup.memory=", cgroup_memory);
|
|
|
|
/*
|
|
* subsys_initcall() for memory controller.
|
|
*
|
|
* Some parts like memcg_hotplug_cpu_dead() have to be initialized from this
|
|
* context because of lock dependencies (cgroup_lock -> cpu hotplug) but
|
|
* basically everything that doesn't depend on a specific mem_cgroup structure
|
|
* should be initialized from here.
|
|
*/
|
|
static int __init mem_cgroup_init(void)
|
|
{
|
|
int cpu, node;
|
|
|
|
#ifdef CONFIG_MEMCG_KMEM
|
|
/*
|
|
* Kmem cache creation is mostly done with the slab_mutex held,
|
|
* so use a workqueue with limited concurrency to avoid stalling
|
|
* all worker threads in case lots of cgroups are created and
|
|
* destroyed simultaneously.
|
|
*/
|
|
memcg_kmem_cache_wq = alloc_workqueue("memcg_kmem_cache", 0, 1);
|
|
BUG_ON(!memcg_kmem_cache_wq);
|
|
#endif
|
|
|
|
cpuhp_setup_state_nocalls(CPUHP_MM_MEMCQ_DEAD, "mm/memctrl:dead", NULL,
|
|
memcg_hotplug_cpu_dead);
|
|
|
|
for_each_possible_cpu(cpu)
|
|
INIT_WORK(&per_cpu_ptr(&memcg_stock, cpu)->work,
|
|
drain_local_stock);
|
|
|
|
for_each_node(node) {
|
|
struct mem_cgroup_tree_per_node *rtpn;
|
|
|
|
rtpn = kzalloc_node(sizeof(*rtpn), GFP_KERNEL,
|
|
node_online(node) ? node : NUMA_NO_NODE);
|
|
|
|
rtpn->rb_root = RB_ROOT;
|
|
rtpn->rb_rightmost = NULL;
|
|
spin_lock_init(&rtpn->lock);
|
|
soft_limit_tree.rb_tree_per_node[node] = rtpn;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
subsys_initcall(mem_cgroup_init);
|
|
|
|
#ifdef CONFIG_MEMCG_SWAP
|
|
static struct mem_cgroup *mem_cgroup_id_get_online(struct mem_cgroup *memcg)
|
|
{
|
|
while (!refcount_inc_not_zero(&memcg->id.ref)) {
|
|
/*
|
|
* The root cgroup cannot be destroyed, so it's refcount must
|
|
* always be >= 1.
|
|
*/
|
|
if (WARN_ON_ONCE(memcg == root_mem_cgroup)) {
|
|
VM_BUG_ON(1);
|
|
break;
|
|
}
|
|
memcg = parent_mem_cgroup(memcg);
|
|
if (!memcg)
|
|
memcg = root_mem_cgroup;
|
|
}
|
|
return memcg;
|
|
}
|
|
|
|
/**
|
|
* mem_cgroup_swapout - transfer a memsw charge to swap
|
|
* @page: page whose memsw charge to transfer
|
|
* @entry: swap entry to move the charge to
|
|
*
|
|
* Transfer the memsw charge of @page to @entry.
|
|
*/
|
|
void mem_cgroup_swapout(struct page *page, swp_entry_t entry)
|
|
{
|
|
struct mem_cgroup *memcg, *swap_memcg;
|
|
unsigned int nr_entries;
|
|
unsigned short oldid;
|
|
|
|
VM_BUG_ON_PAGE(PageLRU(page), page);
|
|
VM_BUG_ON_PAGE(page_count(page), page);
|
|
|
|
if (!do_memsw_account())
|
|
return;
|
|
|
|
memcg = page->mem_cgroup;
|
|
|
|
/* Readahead page, never charged */
|
|
if (!memcg)
|
|
return;
|
|
|
|
/*
|
|
* In case the memcg owning these pages has been offlined and doesn't
|
|
* have an ID allocated to it anymore, charge the closest online
|
|
* ancestor for the swap instead and transfer the memory+swap charge.
|
|
*/
|
|
swap_memcg = mem_cgroup_id_get_online(memcg);
|
|
nr_entries = hpage_nr_pages(page);
|
|
/* Get references for the tail pages, too */
|
|
if (nr_entries > 1)
|
|
mem_cgroup_id_get_many(swap_memcg, nr_entries - 1);
|
|
oldid = swap_cgroup_record(entry, mem_cgroup_id(swap_memcg),
|
|
nr_entries);
|
|
VM_BUG_ON_PAGE(oldid, page);
|
|
mod_memcg_state(swap_memcg, MEMCG_SWAP, nr_entries);
|
|
|
|
page->mem_cgroup = NULL;
|
|
|
|
if (!mem_cgroup_is_root(memcg))
|
|
page_counter_uncharge(&memcg->memory, nr_entries);
|
|
|
|
if (memcg != swap_memcg) {
|
|
if (!mem_cgroup_is_root(swap_memcg))
|
|
page_counter_charge(&swap_memcg->memsw, nr_entries);
|
|
page_counter_uncharge(&memcg->memsw, nr_entries);
|
|
}
|
|
|
|
/*
|
|
* Interrupts should be disabled here because the caller holds the
|
|
* i_pages lock which is taken with interrupts-off. It is
|
|
* important here to have the interrupts disabled because it is the
|
|
* only synchronisation we have for updating the per-CPU variables.
|
|
*/
|
|
VM_BUG_ON(!irqs_disabled());
|
|
mem_cgroup_charge_statistics(memcg, page, PageTransHuge(page),
|
|
-nr_entries);
|
|
memcg_check_events(memcg, page);
|
|
|
|
if (!mem_cgroup_is_root(memcg))
|
|
css_put_many(&memcg->css, nr_entries);
|
|
}
|
|
|
|
/**
|
|
* mem_cgroup_try_charge_swap - try charging swap space for a page
|
|
* @page: page being added to swap
|
|
* @entry: swap entry to charge
|
|
*
|
|
* Try to charge @page's memcg for the swap space at @entry.
|
|
*
|
|
* Returns 0 on success, -ENOMEM on failure.
|
|
*/
|
|
int mem_cgroup_try_charge_swap(struct page *page, swp_entry_t entry)
|
|
{
|
|
unsigned int nr_pages = hpage_nr_pages(page);
|
|
struct page_counter *counter;
|
|
struct mem_cgroup *memcg;
|
|
unsigned short oldid;
|
|
|
|
if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) || !do_swap_account)
|
|
return 0;
|
|
|
|
memcg = page->mem_cgroup;
|
|
|
|
/* Readahead page, never charged */
|
|
if (!memcg)
|
|
return 0;
|
|
|
|
if (!entry.val) {
|
|
memcg_memory_event(memcg, MEMCG_SWAP_FAIL);
|
|
return 0;
|
|
}
|
|
|
|
memcg = mem_cgroup_id_get_online(memcg);
|
|
|
|
if (!mem_cgroup_is_root(memcg) &&
|
|
!page_counter_try_charge(&memcg->swap, nr_pages, &counter)) {
|
|
memcg_memory_event(memcg, MEMCG_SWAP_MAX);
|
|
memcg_memory_event(memcg, MEMCG_SWAP_FAIL);
|
|
mem_cgroup_id_put(memcg);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
/* Get references for the tail pages, too */
|
|
if (nr_pages > 1)
|
|
mem_cgroup_id_get_many(memcg, nr_pages - 1);
|
|
oldid = swap_cgroup_record(entry, mem_cgroup_id(memcg), nr_pages);
|
|
VM_BUG_ON_PAGE(oldid, page);
|
|
mod_memcg_state(memcg, MEMCG_SWAP, nr_pages);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* mem_cgroup_uncharge_swap - uncharge swap space
|
|
* @entry: swap entry to uncharge
|
|
* @nr_pages: the amount of swap space to uncharge
|
|
*/
|
|
void mem_cgroup_uncharge_swap(swp_entry_t entry, unsigned int nr_pages)
|
|
{
|
|
struct mem_cgroup *memcg;
|
|
unsigned short id;
|
|
|
|
if (!do_swap_account)
|
|
return;
|
|
|
|
id = swap_cgroup_record(entry, 0, nr_pages);
|
|
rcu_read_lock();
|
|
memcg = mem_cgroup_from_id(id);
|
|
if (memcg) {
|
|
if (!mem_cgroup_is_root(memcg)) {
|
|
if (cgroup_subsys_on_dfl(memory_cgrp_subsys))
|
|
page_counter_uncharge(&memcg->swap, nr_pages);
|
|
else
|
|
page_counter_uncharge(&memcg->memsw, nr_pages);
|
|
}
|
|
mod_memcg_state(memcg, MEMCG_SWAP, -nr_pages);
|
|
mem_cgroup_id_put_many(memcg, nr_pages);
|
|
}
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
long mem_cgroup_get_nr_swap_pages(struct mem_cgroup *memcg)
|
|
{
|
|
long nr_swap_pages = get_nr_swap_pages();
|
|
|
|
if (!do_swap_account || !cgroup_subsys_on_dfl(memory_cgrp_subsys))
|
|
return nr_swap_pages;
|
|
for (; memcg != root_mem_cgroup; memcg = parent_mem_cgroup(memcg))
|
|
nr_swap_pages = min_t(long, nr_swap_pages,
|
|
READ_ONCE(memcg->swap.max) -
|
|
page_counter_read(&memcg->swap));
|
|
return nr_swap_pages;
|
|
}
|
|
|
|
bool mem_cgroup_swap_full(struct page *page)
|
|
{
|
|
struct mem_cgroup *memcg;
|
|
|
|
VM_BUG_ON_PAGE(!PageLocked(page), page);
|
|
|
|
if (vm_swap_full())
|
|
return true;
|
|
if (!do_swap_account || !cgroup_subsys_on_dfl(memory_cgrp_subsys))
|
|
return false;
|
|
|
|
memcg = page->mem_cgroup;
|
|
if (!memcg)
|
|
return false;
|
|
|
|
for (; memcg != root_mem_cgroup; memcg = parent_mem_cgroup(memcg))
|
|
if (page_counter_read(&memcg->swap) * 2 >= memcg->swap.max)
|
|
return true;
|
|
|
|
return false;
|
|
}
|
|
|
|
/* for remember boot option*/
|
|
#ifdef CONFIG_MEMCG_SWAP_ENABLED
|
|
static int really_do_swap_account __initdata = 1;
|
|
#else
|
|
static int really_do_swap_account __initdata;
|
|
#endif
|
|
|
|
static int __init enable_swap_account(char *s)
|
|
{
|
|
if (!strcmp(s, "1"))
|
|
really_do_swap_account = 1;
|
|
else if (!strcmp(s, "0"))
|
|
really_do_swap_account = 0;
|
|
return 1;
|
|
}
|
|
__setup("swapaccount=", enable_swap_account);
|
|
|
|
static u64 swap_current_read(struct cgroup_subsys_state *css,
|
|
struct cftype *cft)
|
|
{
|
|
struct mem_cgroup *memcg = mem_cgroup_from_css(css);
|
|
|
|
return (u64)page_counter_read(&memcg->swap) * PAGE_SIZE;
|
|
}
|
|
|
|
static int swap_max_show(struct seq_file *m, void *v)
|
|
{
|
|
return seq_puts_memcg_tunable(m,
|
|
READ_ONCE(mem_cgroup_from_seq(m)->swap.max));
|
|
}
|
|
|
|
static ssize_t swap_max_write(struct kernfs_open_file *of,
|
|
char *buf, size_t nbytes, loff_t off)
|
|
{
|
|
struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of));
|
|
unsigned long max;
|
|
int err;
|
|
|
|
buf = strstrip(buf);
|
|
err = page_counter_memparse(buf, "max", &max);
|
|
if (err)
|
|
return err;
|
|
|
|
xchg(&memcg->swap.max, max);
|
|
|
|
return nbytes;
|
|
}
|
|
|
|
static int swap_events_show(struct seq_file *m, void *v)
|
|
{
|
|
struct mem_cgroup *memcg = mem_cgroup_from_seq(m);
|
|
|
|
seq_printf(m, "max %lu\n",
|
|
atomic_long_read(&memcg->memory_events[MEMCG_SWAP_MAX]));
|
|
seq_printf(m, "fail %lu\n",
|
|
atomic_long_read(&memcg->memory_events[MEMCG_SWAP_FAIL]));
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct cftype swap_files[] = {
|
|
{
|
|
.name = "swap.current",
|
|
.flags = CFTYPE_NOT_ON_ROOT,
|
|
.read_u64 = swap_current_read,
|
|
},
|
|
{
|
|
.name = "swap.max",
|
|
.flags = CFTYPE_NOT_ON_ROOT,
|
|
.seq_show = swap_max_show,
|
|
.write = swap_max_write,
|
|
},
|
|
{
|
|
.name = "swap.events",
|
|
.flags = CFTYPE_NOT_ON_ROOT,
|
|
.file_offset = offsetof(struct mem_cgroup, swap_events_file),
|
|
.seq_show = swap_events_show,
|
|
},
|
|
{ } /* terminate */
|
|
};
|
|
|
|
static struct cftype memsw_cgroup_files[] = {
|
|
{
|
|
.name = "memsw.usage_in_bytes",
|
|
.private = MEMFILE_PRIVATE(_MEMSWAP, RES_USAGE),
|
|
.read_u64 = mem_cgroup_read_u64,
|
|
},
|
|
{
|
|
.name = "memsw.max_usage_in_bytes",
|
|
.private = MEMFILE_PRIVATE(_MEMSWAP, RES_MAX_USAGE),
|
|
.write = mem_cgroup_reset,
|
|
.read_u64 = mem_cgroup_read_u64,
|
|
},
|
|
{
|
|
.name = "memsw.limit_in_bytes",
|
|
.private = MEMFILE_PRIVATE(_MEMSWAP, RES_LIMIT),
|
|
.write = mem_cgroup_write,
|
|
.read_u64 = mem_cgroup_read_u64,
|
|
},
|
|
{
|
|
.name = "memsw.failcnt",
|
|
.private = MEMFILE_PRIVATE(_MEMSWAP, RES_FAILCNT),
|
|
.write = mem_cgroup_reset,
|
|
.read_u64 = mem_cgroup_read_u64,
|
|
},
|
|
{ }, /* terminate */
|
|
};
|
|
|
|
static int __init mem_cgroup_swap_init(void)
|
|
{
|
|
if (!mem_cgroup_disabled() && really_do_swap_account) {
|
|
do_swap_account = 1;
|
|
WARN_ON(cgroup_add_dfl_cftypes(&memory_cgrp_subsys,
|
|
swap_files));
|
|
WARN_ON(cgroup_add_legacy_cftypes(&memory_cgrp_subsys,
|
|
memsw_cgroup_files));
|
|
}
|
|
return 0;
|
|
}
|
|
subsys_initcall(mem_cgroup_swap_init);
|
|
|
|
#endif /* CONFIG_MEMCG_SWAP */
|