[patch 09/10] mm: memcontrol: rewrite charge API

From: Johannes Weiner
Date: Thu May 29 2014 - 12:17:25 EST

The memcg charge API charges pages before they are rmapped - i.e. have
an actual "type" - and so every callsite needs its own set of charge
and uncharge functions to know what type is being operated on. Worse,
uncharge has to happen from a context that is still type-specific,
rather than at the end of the page's lifetime with exclusive access,
and so requires a lot of synchronization.

Rewrite the charge API to provide a generic set of try_charge(),
commit_charge() and cancel_charge() transaction operations, much like
what's currently done for swap-in:

mem_cgroup_try_charge() attempts to reserve a charge, reclaiming
pages from the memcg if necessary.

mem_cgroup_commit_charge() commits the page to the charge once it
has a valid page->mapping and PageAnon() reliably tells the type.

mem_cgroup_cancel_charge() aborts the transaction.

This reduces the charge API and enables subsequent patches to
drastically simplify uncharging.

As pages need to be committed after rmap is established but before
they are added to the LRU, page_add_new_anon_rmap() must stop doing
LRU additions again. Revive lru_cache_add_active_or_unevictable().

Signed-off-by: Johannes Weiner <hannes@xxxxxxxxxxx>
---
Documentation/cgroups/memcg_test.txt | 32 +--
include/linux/memcontrol.h | 53 ++---
include/linux/swap.h | 3 +
kernel/events/uprobes.c | 1 +
mm/filemap.c | 9 +-
mm/huge_memory.c | 55 +++--
mm/memcontrol.c | 418 ++++++++++++++---------------------
mm/memory.c | 41 ++--
mm/rmap.c | 19 --
mm/shmem.c | 24 +-
mm/swap.c | 34 +++
mm/swapfile.c | 14 +-
12 files changed, 316 insertions(+), 387 deletions(-)

diff --git a/Documentation/cgroups/memcg_test.txt b/Documentation/cgroups/memcg_test.txt
index 80ac454704b8..bcf750d3cecd 100644
--- a/Documentation/cgroups/memcg_test.txt
+++ b/Documentation/cgroups/memcg_test.txt
@@ -24,24 +24,7 @@ Please note that implementation details can be changed.

a page/swp_entry may be charged (usage += PAGE_SIZE) at

- mem_cgroup_charge_anon()
- Called at new page fault and Copy-On-Write.
-
- mem_cgroup_try_charge_swapin()
- Called at do_swap_page() (page fault on swap entry) and swapoff.
- Followed by charge-commit-cancel protocol. (With swap accounting)
- At commit, a charge recorded in swap_cgroup is removed.
-
- mem_cgroup_charge_file()
- Called at add_to_page_cache()
-
- mem_cgroup_cache_charge_swapin()
- Called at shmem's swapin.
-
- mem_cgroup_prepare_migration()
- Called before migration. "extra" charge is done and followed by
- charge-commit-cancel protocol.
- At commit, charge against oldpage or newpage will be committed.
+ mem_cgroup_try_charge()

2. Uncharge
a page/swp_entry may be uncharged (usage -= PAGE_SIZE) by
@@ -69,19 +52,14 @@ Please note that implementation details can be changed.
to new page is committed. At failure, charge to old page is committed.

3. charge-commit-cancel
- In some case, we can't know this "charge" is valid or not at charging
- (because of races).
- To handle such case, there are charge-commit-cancel functions.
- mem_cgroup_try_charge_XXX
- mem_cgroup_commit_charge_XXX
- mem_cgroup_cancel_charge_XXX
- these are used in swap-in and migration.
+ Memcg pages are charged in two steps:
+ mem_cgroup_try_charge()
+ mem_cgroup_commit_charge() or mem_cgroup_cancel_charge()

At try_charge(), there are no flags to say "this page is charged".
at this point, usage += PAGE_SIZE.

- At commit(), the function checks the page should be charged or not
- and set flags or avoid charging.(usage -= PAGE_SIZE)
+ At commit(), the page is associated with the memcg.

At cancel(), simply usage -= PAGE_SIZE.

diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index a5cf853129ec..bd2cc35babe0 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -54,28 +54,11 @@ struct mem_cgroup_reclaim_cookie {
};

#ifdef CONFIG_MEMCG
-/*
- * All "charge" functions with gfp_mask should use GFP_KERNEL or
- * (gfp_mask & GFP_RECLAIM_MASK). In current implementatin, memcg doesn't
- * alloc memory but reclaims memory from all available zones. So, "where I want
- * memory from" bits of gfp_mask has no meaning. So any bits of that field is
- * available but adding a rule is better. charge functions' gfp_mask should
- * be set to GFP_KERNEL or gfp_mask & GFP_RECLAIM_MASK for avoiding ambiguous
- * codes.
- * (Of course, if memcg does memory allocation in future, GFP_KERNEL is sane.)
- */
-
-extern int mem_cgroup_charge_anon(struct page *page, struct mm_struct *mm,
- gfp_t gfp_mask);
-/* for swap handling */
-extern int mem_cgroup_try_charge_swapin(struct mm_struct *mm,
- struct page *page, gfp_t mask, struct mem_cgroup **memcgp);
-extern void mem_cgroup_commit_charge_swapin(struct page *page,
- struct mem_cgroup *memcg);
-extern void mem_cgroup_cancel_charge_swapin(struct mem_cgroup *memcg);
-
-extern int mem_cgroup_charge_file(struct page *page, struct mm_struct *mm,
- gfp_t gfp_mask);
+int mem_cgroup_try_charge(struct page *page, struct mm_struct *mm,
+ gfp_t gfp_mask, struct mem_cgroup **memcgp);
+void mem_cgroup_commit_charge(struct page *page, struct mem_cgroup *memcg,
+ bool lrucare);
+void mem_cgroup_cancel_charge(struct page *page, struct mem_cgroup *memcg);

struct lruvec *mem_cgroup_zone_lruvec(struct zone *, struct mem_cgroup *);
struct lruvec *mem_cgroup_page_lruvec(struct page *, struct zone *);
@@ -237,30 +220,22 @@ void mem_cgroup_print_bad_page(struct page *page);
#else /* CONFIG_MEMCG */
struct mem_cgroup;

-static inline int mem_cgroup_charge_anon(struct page *page,
- struct mm_struct *mm, gfp_t gfp_mask)
-{
- return 0;
-}
-
-static inline int mem_cgroup_charge_file(struct page *page,
- struct mm_struct *mm, gfp_t gfp_mask)
-{
- return 0;
-}
-
-static inline int mem_cgroup_try_charge_swapin(struct mm_struct *mm,
- struct page *page, gfp_t gfp_mask, struct mem_cgroup **memcgp)
+static inline int mem_cgroup_try_charge(struct page *page, struct mm_struct *mm,
+ gfp_t gfp_mask,
+ struct mem_cgroup **memcgp)
{
+ *memcgp = NULL;
return 0;
}

-static inline void mem_cgroup_commit_charge_swapin(struct page *page,
- struct mem_cgroup *memcg)
+static inline void mem_cgroup_commit_charge(struct page *page,
+ struct mem_cgroup *memcg,
+ bool lrucare)
{
}

-static inline void mem_cgroup_cancel_charge_swapin(struct mem_cgroup *memcg)
+static inline void mem_cgroup_cancel_charge(struct page *page,
+ struct mem_cgroup *memcg)
{
}

diff --git a/include/linux/swap.h b/include/linux/swap.h
index 4bdbee80eede..290905133078 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -321,6 +321,9 @@ extern void swap_setup(void);

extern void add_page_to_unevictable_list(struct page *page);

+extern void lru_cache_add_active_or_unevictable(struct page *page,
+ struct vm_area_struct *vma);
+
/* linux/mm/vmscan.c */
extern unsigned long try_to_free_pages(struct zonelist *zonelist, int order,
gfp_t gfp_mask, nodemask_t *mask);
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index 7f2d4dae54a2..d68e014321f5 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -178,6 +178,7 @@ static int __replace_page(struct vm_area_struct *vma, unsigned long addr,

get_page(kpage);
page_add_new_anon_rmap(kpage, vma, addr);
+ lru_cache_add_active_or_unevictable(kpage, vma);

if (!PageAnon(page)) {
dec_mm_counter(mm, MM_FILEPAGES);
diff --git a/mm/filemap.c b/mm/filemap.c
index dafb06f70a09..114cd89c1cc2 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -560,19 +560,19 @@ static int __add_to_page_cache_locked(struct page *page,
pgoff_t offset, gfp_t gfp_mask,
void **shadowp)
{
+ struct mem_cgroup *memcg;
int error;

VM_BUG_ON_PAGE(!PageLocked(page), page);
VM_BUG_ON_PAGE(PageSwapBacked(page), page);

- error = mem_cgroup_charge_file(page, current->mm,
- gfp_mask & GFP_RECLAIM_MASK);
+ error = mem_cgroup_try_charge(page, current->mm, gfp_mask, &memcg);
if (error)
return error;

error = radix_tree_maybe_preload(gfp_mask & ~__GFP_HIGHMEM);
if (error) {
- mem_cgroup_uncharge_cache_page(page);
+ mem_cgroup_cancel_charge(page, memcg);
return error;
}

@@ -587,13 +587,14 @@ static int __add_to_page_cache_locked(struct page *page,
goto err_insert;
__inc_zone_page_state(page, NR_FILE_PAGES);
spin_unlock_irq(&mapping->tree_lock);
+ mem_cgroup_commit_charge(page, memcg, false);
trace_mm_filemap_add_to_page_cache(page);
return 0;
err_insert:
page->mapping = NULL;
/* Leave page->index set: truncation relies upon it */
spin_unlock_irq(&mapping->tree_lock);
- mem_cgroup_uncharge_cache_page(page);
+ mem_cgroup_cancel_charge(page, memcg);
page_cache_release(page);
return error;
}
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index c5ff461e0253..7acc09d92afb 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -715,13 +715,20 @@ static int __do_huge_pmd_anonymous_page(struct mm_struct *mm,
unsigned long haddr, pmd_t *pmd,
struct page *page)
{
+ struct mem_cgroup *memcg;
pgtable_t pgtable;
spinlock_t *ptl;

VM_BUG_ON_PAGE(!PageCompound(page), page);
+
+ if (mem_cgroup_try_charge(page, mm, GFP_KERNEL, &memcg))
+ return VM_FAULT_OOM;
+
pgtable = pte_alloc_one(mm, haddr);
- if (unlikely(!pgtable))
+ if (unlikely(!pgtable)) {
+ mem_cgroup_cancel_charge(page, memcg);
return VM_FAULT_OOM;
+ }

clear_huge_page(page, haddr, HPAGE_PMD_NR);
/*
@@ -734,7 +741,7 @@ static int __do_huge_pmd_anonymous_page(struct mm_struct *mm,
ptl = pmd_lock(mm, pmd);
if (unlikely(!pmd_none(*pmd))) {
spin_unlock(ptl);
- mem_cgroup_uncharge_page(page);
+ mem_cgroup_cancel_charge(page, memcg);
put_page(page);
pte_free(mm, pgtable);
} else {
@@ -742,6 +749,8 @@ static int __do_huge_pmd_anonymous_page(struct mm_struct *mm,
entry = mk_huge_pmd(page, vma->vm_page_prot);
entry = maybe_pmd_mkwrite(pmd_mkdirty(entry), vma);
page_add_new_anon_rmap(page, vma, haddr);
+ mem_cgroup_commit_charge(page, memcg, false);
+ lru_cache_add_active_or_unevictable(page, vma);
pgtable_trans_huge_deposit(mm, pmd, pgtable);
set_pmd_at(mm, haddr, pmd, entry);
add_mm_counter(mm, MM_ANONPAGES, HPAGE_PMD_NR);
@@ -827,13 +836,7 @@ int do_huge_pmd_anonymous_page(struct mm_struct *mm, struct vm_area_struct *vma,
count_vm_event(THP_FAULT_FALLBACK);
return VM_FAULT_FALLBACK;
}
- if (unlikely(mem_cgroup_charge_anon(page, mm, GFP_KERNEL))) {
- put_page(page);
- count_vm_event(THP_FAULT_FALLBACK);
- return VM_FAULT_FALLBACK;
- }
if (unlikely(__do_huge_pmd_anonymous_page(mm, vma, haddr, pmd, page))) {
- mem_cgroup_uncharge_page(page);
put_page(page);
count_vm_event(THP_FAULT_FALLBACK);
return VM_FAULT_FALLBACK;
@@ -948,6 +951,7 @@ static int do_huge_pmd_wp_page_fallback(struct mm_struct *mm,
struct page *page,
unsigned long haddr)
{
+ struct mem_cgroup *memcg;
spinlock_t *ptl;
pgtable_t pgtable;
pmd_t _pmd;
@@ -968,20 +972,21 @@ static int do_huge_pmd_wp_page_fallback(struct mm_struct *mm,
__GFP_OTHER_NODE,
vma, address, page_to_nid(page));
if (unlikely(!pages[i] ||
- mem_cgroup_charge_anon(pages[i], mm,
- GFP_KERNEL))) {
+ mem_cgroup_try_charge(pages[i], mm, GFP_KERNEL,
+ &memcg))) {
if (pages[i])
put_page(pages[i]);
- mem_cgroup_uncharge_start();
while (--i >= 0) {
- mem_cgroup_uncharge_page(pages[i]);
+ memcg = (void *)page_private(pages[i]);
+ set_page_private(pages[i], 0);
+ mem_cgroup_cancel_charge(pages[i], memcg);
put_page(pages[i]);
}
- mem_cgroup_uncharge_end();
kfree(pages);
ret |= VM_FAULT_OOM;
goto out;
}
+ set_page_private(pages[i], (unsigned long)memcg);
}

for (i = 0; i < HPAGE_PMD_NR; i++) {
@@ -1010,7 +1015,11 @@ static int do_huge_pmd_wp_page_fallback(struct mm_struct *mm,
pte_t *pte, entry;
entry = mk_pte(pages[i], vma->vm_page_prot);
entry = maybe_mkwrite(pte_mkdirty(entry), vma);
+ memcg = (void *)page_private(pages[i]);
+ set_page_private(pages[i], 0);
page_add_new_anon_rmap(pages[i], vma, haddr);
+ mem_cgroup_commit_charge(pages[i], memcg, false);
+ lru_cache_add_active_or_unevictable(pages[i], vma);
pte = pte_offset_map(&_pmd, haddr);
VM_BUG_ON(!pte_none(*pte));
set_pte_at(mm, haddr, pte, entry);
@@ -1034,12 +1043,12 @@ out:
out_free_pages:
spin_unlock(ptl);
mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
- mem_cgroup_uncharge_start();
for (i = 0; i < HPAGE_PMD_NR; i++) {
- mem_cgroup_uncharge_page(pages[i]);
+ memcg = (void *)page_private(pages[i]);
+ set_page_private(pages[i], 0);
+ mem_cgroup_cancel_charge(pages[i], memcg);
put_page(pages[i]);
}
- mem_cgroup_uncharge_end();
kfree(pages);
goto out;
}
@@ -1050,6 +1059,7 @@ int do_huge_pmd_wp_page(struct mm_struct *mm, struct vm_area_struct *vma,
spinlock_t *ptl;
int ret = 0;
struct page *page = NULL, *new_page;
+ struct mem_cgroup *memcg;
unsigned long haddr;
unsigned long mmun_start; /* For mmu_notifiers */
unsigned long mmun_end; /* For mmu_notifiers */
@@ -1101,7 +1111,7 @@ alloc:
goto out;
}

- if (unlikely(mem_cgroup_charge_anon(new_page, mm, GFP_KERNEL))) {
+ if (unlikely(mem_cgroup_try_charge(new_page, mm, GFP_KERNEL, &memcg))) {
put_page(new_page);
if (page) {
split_huge_page(page);
@@ -1130,7 +1140,7 @@ alloc:
put_page(page);
if (unlikely(!pmd_same(*pmd, orig_pmd))) {
spin_unlock(ptl);
- mem_cgroup_uncharge_page(new_page);
+ mem_cgroup_cancel_charge(new_page, memcg);
put_page(new_page);
goto out_mn;
} else {
@@ -1139,6 +1149,8 @@ alloc:
entry = maybe_pmd_mkwrite(pmd_mkdirty(entry), vma);
pmdp_clear_flush(vma, haddr, pmd);
page_add_new_anon_rmap(new_page, vma, haddr);
+ mem_cgroup_commit_charge(new_page, memcg, false);
+ lru_cache_add_active_or_unevictable(new_page, vma);
set_pmd_at(mm, haddr, pmd, entry);
update_mmu_cache_pmd(vma, address, pmd);
if (!page) {
@@ -2358,6 +2370,7 @@ static void collapse_huge_page(struct mm_struct *mm,
spinlock_t *pmd_ptl, *pte_ptl;
int isolated;
unsigned long hstart, hend;
+ struct mem_cgroup *memcg;
unsigned long mmun_start; /* For mmu_notifiers */
unsigned long mmun_end; /* For mmu_notifiers */

@@ -2368,7 +2381,7 @@ static void collapse_huge_page(struct mm_struct *mm,
if (!new_page)
return;

- if (unlikely(mem_cgroup_charge_anon(new_page, mm, GFP_KERNEL)))
+ if (unlikely(mem_cgroup_try_charge(new_page, mm, GFP_KERNEL, &memcg)))
return;

/*
@@ -2457,6 +2470,8 @@ static void collapse_huge_page(struct mm_struct *mm,
spin_lock(pmd_ptl);
BUG_ON(!pmd_none(*pmd));
page_add_new_anon_rmap(new_page, vma, address);
+ mem_cgroup_commit_charge(new_page, memcg, false);
+ lru_cache_add_active_or_unevictable(new_page, vma);
pgtable_trans_huge_deposit(mm, pmd, pgtable);
set_pmd_at(mm, address, pmd, _pmd);
update_mmu_cache_pmd(vma, address, pmd);
@@ -2470,7 +2485,7 @@ out_up_write:
return;

out:
- mem_cgroup_uncharge_page(new_page);
+ mem_cgroup_cancel_charge(new_page, memcg);
goto out_up_write;
}

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index cd024dfb039a..9458c9e3e08c 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -2552,19 +2552,8 @@ static int memcg_cpu_hotplug_callback(struct notifier_block *nb,
return NOTIFY_OK;
}

-/**
- * mem_cgroup_try_charge - try charging a memcg
- * @memcg: memcg to charge
- * @nr_pages: number of pages to charge
- * @oom: trigger OOM if reclaim fails
- *
- * Returns 0 if @memcg was charged successfully, -EINTR if the charge
- * was bypassed to root_mem_cgroup, and -ENOMEM if the charge failed.
- */
-static int mem_cgroup_try_charge(struct mem_cgroup *memcg,
- gfp_t gfp_mask,
- unsigned int nr_pages,
- bool oom)
+static int try_charge(struct mem_cgroup *memcg, gfp_t gfp_mask,
+ unsigned int nr_pages, bool oom)
{
unsigned int batch = max(CHARGE_BATCH, nr_pages);
int nr_retries = MEM_CGROUP_RECLAIM_RETRIES;
@@ -2666,42 +2655,7 @@ done:
return ret;
}

-/**
- * mem_cgroup_try_charge_mm - try charging a mm
- * @mm: mm_struct to charge
- * @nr_pages: number of pages to charge
- * @oom: trigger OOM if reclaim fails
- *
- * Returns the charged mem_cgroup associated with the given mm_struct or
- * NULL the charge failed.
- */
-static struct mem_cgroup *mem_cgroup_try_charge_mm(struct mm_struct *mm,
- gfp_t gfp_mask,
- unsigned int nr_pages,
- bool oom)
-
-{
- struct mem_cgroup *memcg;
- int ret;
-
- memcg = get_mem_cgroup_from_mm(mm);
- ret = mem_cgroup_try_charge(memcg, gfp_mask, nr_pages, oom);
- css_put(&memcg->css);
- if (ret == -EINTR)
- memcg = root_mem_cgroup;
- else if (ret)
- memcg = NULL;
-
- return memcg;
-}
-
-/*
- * Somemtimes we have to undo a charge we got by try_charge().
- * This function is for that and do uncharge, put css's refcnt.
- * gotten by try_charge().
- */
-static void __mem_cgroup_cancel_charge(struct mem_cgroup *memcg,
- unsigned int nr_pages)
+static void cancel_charge(struct mem_cgroup *memcg, unsigned int nr_pages)
{
unsigned long bytes = nr_pages * PAGE_SIZE;

@@ -2807,17 +2761,13 @@ struct mem_cgroup *try_get_mem_cgroup_from_page(struct page *page)
return memcg;
}

-static void __mem_cgroup_commit_charge(struct mem_cgroup *memcg,
- struct page *page,
- unsigned int nr_pages,
- enum charge_type ctype,
- bool lrucare)
+static void commit_charge(struct page *page, struct mem_cgroup *memcg,
+ unsigned int nr_pages, bool anon, bool lrucare)
{
struct page_cgroup *pc = lookup_page_cgroup(page);
struct zone *uninitialized_var(zone);
struct lruvec *lruvec;
bool was_on_lru = false;
- bool anon;

lock_page_cgroup(pc);
VM_BUG_ON_PAGE(PageCgroupUsed(pc), page);
@@ -2854,11 +2804,6 @@ static void __mem_cgroup_commit_charge(struct mem_cgroup *memcg,
spin_unlock_irq(&zone->lru_lock);
}

- if (ctype == MEM_CGROUP_CHARGE_TYPE_ANON)
- anon = true;
- else
- anon = false;
-
mem_cgroup_charge_statistics(memcg, page, anon, nr_pages);
unlock_page_cgroup(pc);

@@ -2929,22 +2874,21 @@ static int memcg_charge_kmem(struct mem_cgroup *memcg, gfp_t gfp, u64 size)
if (ret)
return ret;

- ret = mem_cgroup_try_charge(memcg, gfp, size >> PAGE_SHIFT,
- oom_gfp_allowed(gfp));
+ ret = try_charge(memcg, gfp, size >> PAGE_SHIFT, oom_gfp_allowed(gfp));
if (ret == -EINTR) {
/*
- * mem_cgroup_try_charge() chosed to bypass to root due to
- * OOM kill or fatal signal. Since our only options are to
- * either fail the allocation or charge it to this cgroup, do
- * it as a temporary condition. But we can't fail. From a
- * kmem/slab perspective, the cache has already been selected,
- * by mem_cgroup_kmem_get_cache(), so it is too late to change
+ * try_charge() chose to bypass to root due to OOM kill or
+ * fatal signal. Since our only options are to either fail
+ * the allocation or charge it to this cgroup, do it as a
+ * temporary condition. But we can't fail. From a kmem/slab
+ * perspective, the cache has already been selected, by
+ * mem_cgroup_kmem_get_cache(), so it is too late to change
* our minds.
*
* This condition will only trigger if the task entered
- * memcg_charge_kmem in a sane state, but was OOM-killed during
- * mem_cgroup_try_charge() above. Tasks that were already
- * dying when the allocation triggers should have been already
+ * memcg_charge_kmem in a sane state, but was OOM-killed
+ * during try_charge() above. Tasks that were already dying
+ * when the allocation triggers should have been already
* directed to the root cgroup in memcontrol.h
*/
res_counter_charge_nofail(&memcg->res, size, &fail_res);
@@ -3666,170 +3610,6 @@ out:
return ret;
}

-int mem_cgroup_charge_anon(struct page *page,
- struct mm_struct *mm, gfp_t gfp_mask)
-{
- unsigned int nr_pages = 1;
- struct mem_cgroup *memcg;
- bool oom = true;
-
- if (mem_cgroup_disabled())
- return 0;
-
- VM_BUG_ON_PAGE(page_mapped(page), page);
- VM_BUG_ON_PAGE(page->mapping && !PageAnon(page), page);
- VM_BUG_ON(!mm);
-
- if (PageTransHuge(page)) {
- nr_pages <<= compound_order(page);
- VM_BUG_ON_PAGE(!PageTransHuge(page), page);
- /*
- * Never OOM-kill a process for a huge page. The
- * fault handler will fall back to regular pages.
- */
- oom = false;
- }
-
- memcg = mem_cgroup_try_charge_mm(mm, gfp_mask, nr_pages, oom);
- if (!memcg)
- return -ENOMEM;
- __mem_cgroup_commit_charge(memcg, page, nr_pages,
- MEM_CGROUP_CHARGE_TYPE_ANON, false);
- return 0;
-}
-
-/*
- * While swap-in, try_charge -> commit or cancel, the page is locked.
- * And when try_charge() successfully returns, one refcnt to memcg without
- * struct page_cgroup is acquired. This refcnt will be consumed by
- * "commit()" or removed by "cancel()"
- */
-static int __mem_cgroup_try_charge_swapin(struct mm_struct *mm,
- struct page *page,
- gfp_t mask,
- struct mem_cgroup **memcgp)
-{
- struct mem_cgroup *memcg = NULL;
- struct page_cgroup *pc;
- int ret;
-
- pc = lookup_page_cgroup(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.
- */
- if (PageCgroupUsed(pc))
- goto out;
- if (do_swap_account)
- memcg = try_get_mem_cgroup_from_page(page);
- if (!memcg)
- memcg = get_mem_cgroup_from_mm(mm);
- ret = mem_cgroup_try_charge(memcg, mask, 1, true);
- css_put(&memcg->css);
- if (ret == -EINTR)
- memcg = root_mem_cgroup;
- else if (ret)
- return ret;
-out:
- *memcgp = memcg;
- return 0;
-}
-
-int mem_cgroup_try_charge_swapin(struct mm_struct *mm, struct page *page,
- gfp_t gfp_mask, struct mem_cgroup **memcgp)
-{
- if (mem_cgroup_disabled()) {
- *memcgp = NULL;
- return 0;
- }
- /*
- * A racing thread's fault, or swapoff, may have already
- * updated the pte, and even removed page from swap cache: in
- * those cases unuse_pte()'s pte_same() test will fail; but
- * there's also a KSM case which does need to charge the page.
- */
- if (!PageSwapCache(page)) {
- struct mem_cgroup *memcg;
-
- memcg = mem_cgroup_try_charge_mm(mm, gfp_mask, 1, true);
- if (!memcg)
- return -ENOMEM;
- *memcgp = memcg;
- return 0;
- }
- return __mem_cgroup_try_charge_swapin(mm, page, gfp_mask, memcgp);
-}
-
-void mem_cgroup_cancel_charge_swapin(struct mem_cgroup *memcg)
-{
- if (mem_cgroup_disabled())
- return;
- if (!memcg)
- return;
- __mem_cgroup_cancel_charge(memcg, 1);
-}
-
-static void
-__mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *memcg,
- enum charge_type ctype)
-{
- if (mem_cgroup_disabled())
- return;
- if (!memcg)
- return;
-
- __mem_cgroup_commit_charge(memcg, page, 1, ctype, true);
- /*
- * Now swap is on-memory. This means this page may be
- * counted both as mem and swap....double count.
- * Fix it by uncharging from memsw. Basically, this SwapCache is stable
- * under lock_page(). But in do_swap_page()::memory.c, reuse_swap_page()
- * may call delete_from_swap_cache() before reach here.
- */
- if (do_swap_account && PageSwapCache(page)) {
- swp_entry_t ent = {.val = page_private(page)};
- mem_cgroup_uncharge_swap(ent);
- }
-}
-
-void mem_cgroup_commit_charge_swapin(struct page *page,
- struct mem_cgroup *memcg)
-{
- __mem_cgroup_commit_charge_swapin(page, memcg,
- MEM_CGROUP_CHARGE_TYPE_ANON);
-}
-
-int mem_cgroup_charge_file(struct page *page, struct mm_struct *mm,
- gfp_t gfp_mask)
-{
- enum charge_type type = MEM_CGROUP_CHARGE_TYPE_CACHE;
- struct mem_cgroup *memcg;
- int ret;
-
- if (mem_cgroup_disabled())
- return 0;
- if (PageCompound(page))
- return 0;
-
- if (PageSwapCache(page)) { /* shmem */
- ret = __mem_cgroup_try_charge_swapin(mm, page,
- gfp_mask, &memcg);
- if (ret)
- return ret;
- __mem_cgroup_commit_charge_swapin(page, memcg, type);
- return 0;
- }
-
- memcg = mem_cgroup_try_charge_mm(mm, gfp_mask, 1, true);
- if (!memcg)
- return -ENOMEM;
- __mem_cgroup_commit_charge(memcg, page, 1, type, false);
- return 0;
-}
-
static void mem_cgroup_do_uncharge(struct mem_cgroup *memcg,
unsigned int nr_pages,
const enum charge_type ctype)
@@ -4176,7 +3956,6 @@ void mem_cgroup_prepare_migration(struct page *page, struct page *newpage,
struct mem_cgroup *memcg = NULL;
unsigned int nr_pages = 1;
struct page_cgroup *pc;
- enum charge_type ctype;

*memcgp = NULL;

@@ -4238,16 +4017,12 @@ void mem_cgroup_prepare_migration(struct page *page, struct page *newpage,
* page. In the case new page is migrated but not remapped, new page's
* mapcount will be finally 0 and we call uncharge in end_migration().
*/
- if (PageAnon(page))
- ctype = MEM_CGROUP_CHARGE_TYPE_ANON;
- else
- ctype = MEM_CGROUP_CHARGE_TYPE_CACHE;
/*
* The page is committed to the memcg, but it's not actually
* charged to the res_counter since we plan on replacing the
* old one and only one page is going to be left afterwards.
*/
- __mem_cgroup_commit_charge(memcg, newpage, nr_pages, ctype, false);
+ commit_charge(newpage, memcg, nr_pages, PageAnon(page), false);
}

/* remove redundant charge if migration failed*/
@@ -4306,7 +4081,6 @@ void mem_cgroup_replace_page_cache(struct page *oldpage,
{
struct mem_cgroup *memcg = NULL;
struct page_cgroup *pc;
- enum charge_type type = MEM_CGROUP_CHARGE_TYPE_CACHE;

if (mem_cgroup_disabled())
return;
@@ -4332,7 +4106,7 @@ void mem_cgroup_replace_page_cache(struct page *oldpage,
* the newpage may be on LRU(or pagevec for LRU) already. We lock
* LRU while we overwrite pc->mem_cgroup.
*/
- __mem_cgroup_commit_charge(memcg, newpage, 1, type, true);
+ commit_charge(newpage, memcg, 1, false, true);
}

#ifdef CONFIG_DEBUG_VM
@@ -6408,7 +6182,7 @@ one_by_one:
batch_count = PRECHARGE_COUNT_AT_ONCE;
cond_resched();
}
- ret = mem_cgroup_try_charge(memcg, GFP_KERNEL, 1, false);
+ ret = try_charge(memcg, GFP_KERNEL, 1, false);
/*
* In case of failure, any residual charges against
* mc.to will be dropped by mem_cgroup_clear_mc()
@@ -6416,7 +6190,7 @@ one_by_one:
* bypassed to root right away or they'll be lost.
*/
if (ret == -EINTR)
- __mem_cgroup_cancel_charge(root_mem_cgroup, 1);
+ cancel_charge(root_mem_cgroup, 1);
if (ret)
return ret;
mc.precharge++;
@@ -6679,7 +6453,7 @@ static void __mem_cgroup_clear_mc(void)

/* we must uncharge all the leftover precharges from mc.to */
if (mc.precharge) {
- __mem_cgroup_cancel_charge(mc.to, mc.precharge);
+ cancel_charge(mc.to, mc.precharge);
mc.precharge = 0;
}
/*
@@ -6687,7 +6461,7 @@ static void __mem_cgroup_clear_mc(void)
* we must uncharge here.
*/
if (mc.moved_charge) {
- __mem_cgroup_cancel_charge(mc.from, mc.moved_charge);
+ cancel_charge(mc.from, mc.moved_charge);
mc.moved_charge = 0;
}
/* we must fixup refcnts and charges */
@@ -7001,6 +6775,156 @@ static void __init enable_swap_cgroup(void)
}
#endif

+/**
+ * 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
+ *
+ * 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)
+{
+ struct mem_cgroup *memcg = NULL;
+ unsigned int nr_pages = 1;
+ bool oom = true;
+ int ret = 0;
+
+ if (mem_cgroup_disabled())
+ goto out;
+
+ if (PageSwapCache(page)) {
+ struct page_cgroup *pc = lookup_page_cgroup(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.
+ */
+ if (PageCgroupUsed(pc))
+ goto out;
+ }
+
+ if (PageTransHuge(page)) {
+ nr_pages <<= compound_order(page);
+ VM_BUG_ON_PAGE(!PageTransHuge(page), page);
+ /*
+ * Never OOM-kill a process for a huge page. The
+ * fault handler will fall back to regular pages.
+ */
+ oom = false;
+ }
+
+ if (do_swap_account && PageSwapCache(page))
+ memcg = try_get_mem_cgroup_from_page(page);
+ if (!memcg)
+ memcg = get_mem_cgroup_from_mm(mm);
+
+ ret = try_charge(memcg, gfp_mask, nr_pages, oom);
+
+ css_put(&memcg->css);
+
+ if (ret == -EINTR) {
+ memcg = root_mem_cgroup;
+ ret = 0;
+ }
+out:
+ *memcgp = memcg;
+ 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
+ *
+ * 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)
+{
+ unsigned int nr_pages = 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;
+
+ if (PageTransHuge(page)) {
+ nr_pages <<= compound_order(page);
+ VM_BUG_ON_PAGE(!PageTransHuge(page), page);
+ }
+
+ commit_charge(page, memcg, nr_pages, PageAnon(page), lrucare);
+
+ if (do_swap_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);
+ }
+}
+
+/**
+ * mem_cgroup_cancel_charge - cancel a page charge
+ * @page: page to charge
+ * @memcg: memcg to charge the page to
+ *
+ * Cancel a charge transaction started by mem_cgroup_try_charge().
+ */
+void mem_cgroup_cancel_charge(struct page *page, struct mem_cgroup *memcg)
+{
+ unsigned int nr_pages = 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;
+
+ if (PageTransHuge(page)) {
+ nr_pages <<= compound_order(page);
+ VM_BUG_ON_PAGE(!PageTransHuge(page), page);
+ }
+
+ cancel_charge(memcg, nr_pages);
+}
+
/*
* subsys_initcall() for memory controller.
*
diff --git a/mm/memory.c b/mm/memory.c
index e9a3c0fe368d..3b95ee253c19 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -2049,6 +2049,7 @@ static int do_wp_page(struct mm_struct *mm, struct vm_area_struct *vma,
struct page *dirty_page = NULL;
unsigned long mmun_start = 0; /* For mmu_notifiers */
unsigned long mmun_end = 0; /* For mmu_notifiers */
+ struct mem_cgroup *memcg;

old_page = vm_normal_page(vma, address, orig_pte);
if (!old_page) {
@@ -2204,7 +2205,7 @@ gotten:
}
__SetPageUptodate(new_page);

- if (mem_cgroup_charge_anon(new_page, mm, GFP_KERNEL))
+ if (mem_cgroup_try_charge(new_page, mm, GFP_KERNEL, &memcg))
goto oom_free_new;

mmun_start = address & PAGE_MASK;
@@ -2234,6 +2235,8 @@ gotten:
*/
ptep_clear_flush(vma, address, page_table);
page_add_new_anon_rmap(new_page, vma, address);
+ mem_cgroup_commit_charge(new_page, memcg, false);
+ lru_cache_add_active_or_unevictable(new_page, vma);
/*
* We call the notify macro here because, when using secondary
* mmu page tables (such as kvm shadow page tables), we want the
@@ -2271,7 +2274,7 @@ gotten:
new_page = old_page;
ret |= VM_FAULT_WRITE;
} else
- mem_cgroup_uncharge_page(new_page);
+ mem_cgroup_cancel_charge(new_page, memcg);

if (new_page)
page_cache_release(new_page);
@@ -2407,10 +2410,10 @@ static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma,
{
spinlock_t *ptl;
struct page *page, *swapcache;
+ struct mem_cgroup *memcg;
swp_entry_t entry;
pte_t pte;
int locked;
- struct mem_cgroup *ptr;
int exclusive = 0;
int ret = 0;

@@ -2486,7 +2489,7 @@ static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma,
goto out_page;
}

- if (mem_cgroup_try_charge_swapin(mm, page, GFP_KERNEL, &ptr)) {
+ if (mem_cgroup_try_charge(page, mm, GFP_KERNEL, &memcg)) {
ret = VM_FAULT_OOM;
goto out_page;
}
@@ -2511,10 +2514,6 @@ static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma,
* while the page is counted on swap but not yet in mapcount i.e.
* before page_add_anon_rmap() and swap_free(); try_to_free_swap()
* must be called after the swap_free(), or it will never succeed.
- * Because delete_from_swap_page() may be called by reuse_swap_page(),
- * mem_cgroup_commit_charge_swapin() may not be able to find swp_entry
- * in page->private. In this case, a record in swap_cgroup is silently
- * discarded at swap_free().
*/

inc_mm_counter_fast(mm, MM_ANONPAGES);
@@ -2530,12 +2529,14 @@ static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma,
if (pte_swp_soft_dirty(orig_pte))
pte = pte_mksoft_dirty(pte);
set_pte_at(mm, address, page_table, pte);
- if (page == swapcache)
+ if (page == swapcache) {
do_page_add_anon_rmap(page, vma, address, exclusive);
- else /* ksm created a completely new copy */
+ mem_cgroup_commit_charge(page, memcg, true);
+ } else { /* ksm created a completely new copy */
page_add_new_anon_rmap(page, vma, address);
- /* It's better to call commit-charge after rmap is established */
- mem_cgroup_commit_charge_swapin(page, ptr);
+ mem_cgroup_commit_charge(page, memcg, false);
+ lru_cache_add_active_or_unevictable(page, vma);
+ }

swap_free(entry);
if (vm_swap_full() || (vma->vm_flags & VM_LOCKED) || PageMlocked(page))
@@ -2568,7 +2569,7 @@ unlock:
out:
return ret;
out_nomap:
- mem_cgroup_cancel_charge_swapin(ptr);
+ mem_cgroup_cancel_charge(page, memcg);
pte_unmap_unlock(page_table, ptl);
out_page:
unlock_page(page);
@@ -2624,6 +2625,7 @@ static int do_anonymous_page(struct mm_struct *mm, struct vm_area_struct *vma,
unsigned long address, pte_t *page_table, pmd_t *pmd,
unsigned int flags)
{
+ struct mem_cgroup *memcg;
struct page *page;
spinlock_t *ptl;
pte_t entry;
@@ -2657,7 +2659,7 @@ static int do_anonymous_page(struct mm_struct *mm, struct vm_area_struct *vma,
*/
__SetPageUptodate(page);

- if (mem_cgroup_charge_anon(page, mm, GFP_KERNEL))
+ if (mem_cgroup_try_charge(page, mm, GFP_KERNEL, &memcg))
goto oom_free_page;

entry = mk_pte(page, vma->vm_page_prot);
@@ -2670,6 +2672,8 @@ static int do_anonymous_page(struct mm_struct *mm, struct vm_area_struct *vma,

inc_mm_counter_fast(mm, MM_ANONPAGES);
page_add_new_anon_rmap(page, vma, address);
+ mem_cgroup_commit_charge(page, memcg, false);
+ lru_cache_add_active_or_unevictable(page, vma);
setpte:
set_pte_at(mm, address, page_table, entry);

@@ -2679,7 +2683,7 @@ unlock:
pte_unmap_unlock(page_table, ptl);
return 0;
release:
- mem_cgroup_uncharge_page(page);
+ mem_cgroup_cancel_charge(page, memcg);
page_cache_release(page);
goto unlock;
oom_free_page:
@@ -2902,6 +2906,7 @@ static int do_cow_fault(struct mm_struct *mm, struct vm_area_struct *vma,
pgoff_t pgoff, unsigned int flags, pte_t orig_pte)
{
struct page *fault_page, *new_page;
+ struct mem_cgroup *memcg;
spinlock_t *ptl;
pte_t *pte;
int ret;
@@ -2913,7 +2918,7 @@ static int do_cow_fault(struct mm_struct *mm, struct vm_area_struct *vma,
if (!new_page)
return VM_FAULT_OOM;

- if (mem_cgroup_charge_anon(new_page, mm, GFP_KERNEL)) {
+ if (mem_cgroup_try_charge(new_page, mm, GFP_KERNEL, &memcg)) {
page_cache_release(new_page);
return VM_FAULT_OOM;
}
@@ -2933,12 +2938,14 @@ static int do_cow_fault(struct mm_struct *mm, struct vm_area_struct *vma,
goto uncharge_out;
}
do_set_pte(vma, address, new_page, pte, true, true);
+ mem_cgroup_commit_charge(new_page, memcg, false);
+ lru_cache_add_active_or_unevictable(new_page, vma);
pte_unmap_unlock(pte, ptl);
unlock_page(fault_page);
page_cache_release(fault_page);
return ret;
uncharge_out:
- mem_cgroup_uncharge_page(new_page);
+ mem_cgroup_cancel_charge(new_page, memcg);
page_cache_release(new_page);
return ret;
}
diff --git a/mm/rmap.c b/mm/rmap.c
index 3333baab6ece..b4b1d1424ab3 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -1026,25 +1026,6 @@ void page_add_new_anon_rmap(struct page *page,
__mod_zone_page_state(page_zone(page), NR_ANON_PAGES,
hpage_nr_pages(page));
__page_set_anon_rmap(page, vma, address, 1);
-
- VM_BUG_ON_PAGE(PageLRU(page), page);
- if (likely((vma->vm_flags & (VM_LOCKED | VM_SPECIAL)) != VM_LOCKED)) {
- SetPageActive(page);
- lru_cache_add(page);
- return;
- }
-
- if (!TestSetPageMlocked(page)) {
- /*
- * We use the irq-unsafe __mod_zone_page_stat because this
- * counter is not modified from interrupt context, and the pte
- * lock is held(spinlock), which implies preemption disabled.
- */
- __mod_zone_page_state(page_zone(page), NR_MLOCK,
- hpage_nr_pages(page));
- count_vm_event(UNEVICTABLE_PGMLOCKED);
- }
- add_page_to_unevictable_list(page);
}

/**
diff --git a/mm/shmem.c b/mm/shmem.c
index f484c276e994..ea968bf84942 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -668,6 +668,7 @@ int shmem_unuse(swp_entry_t swap, struct page *page)
{
struct list_head *this, *next;
struct shmem_inode_info *info;
+ struct mem_cgroup *memcg;
int found = 0;
int error = 0;

@@ -683,7 +684,7 @@ int shmem_unuse(swp_entry_t swap, struct page *page)
* the shmem_swaplist_mutex which might hold up shmem_writepage().
* Charged back to the user (not to caller) when swap account is used.
*/
- error = mem_cgroup_charge_file(page, current->mm, GFP_KERNEL);
+ error = mem_cgroup_try_charge(page, current->mm, GFP_KERNEL, &memcg);
if (error)
goto out;
/* No radix_tree_preload: swap entry keeps a place for page in tree */
@@ -701,8 +702,11 @@ int shmem_unuse(swp_entry_t swap, struct page *page)
}
mutex_unlock(&shmem_swaplist_mutex);

- if (found < 0)
+ if (found < 0) {
error = found;
+ mem_cgroup_cancel_charge(page, memcg);
+ } else
+ mem_cgroup_commit_charge(page, memcg, true);
out:
unlock_page(page);
page_cache_release(page);
@@ -1005,6 +1009,7 @@ static int shmem_getpage_gfp(struct inode *inode, pgoff_t index,
struct address_space *mapping = inode->i_mapping;
struct shmem_inode_info *info;
struct shmem_sb_info *sbinfo;
+ struct mem_cgroup *memcg;
struct page *page;
swp_entry_t swap;
int error;
@@ -1080,8 +1085,7 @@ repeat:
goto failed;
}

- error = mem_cgroup_charge_file(page, current->mm,
- gfp & GFP_RECLAIM_MASK);
+ error = mem_cgroup_try_charge(page, current->mm, gfp, &memcg);
if (!error) {
error = shmem_add_to_page_cache(page, mapping, index,
gfp, swp_to_radix_entry(swap));
@@ -1097,12 +1101,16 @@ repeat:
* Reset swap.val? No, leave it so "failed" goes back to
* "repeat": reading a hole and writing should succeed.
*/
- if (error)
+ if (error) {
+ mem_cgroup_cancel_charge(page, memcg);
delete_from_swap_cache(page);
+ }
}
if (error)
goto failed;

+ mem_cgroup_commit_charge(page, memcg, true);
+
spin_lock(&info->lock);
info->swapped--;
shmem_recalc_inode(inode);
@@ -1134,8 +1142,7 @@ repeat:

__SetPageSwapBacked(page);
__set_page_locked(page);
- error = mem_cgroup_charge_file(page, current->mm,
- gfp & GFP_RECLAIM_MASK);
+ error = mem_cgroup_try_charge(page, current->mm, gfp, &memcg);
if (error)
goto decused;
error = radix_tree_maybe_preload(gfp & GFP_RECLAIM_MASK);
@@ -1145,9 +1152,10 @@ repeat:
radix_tree_preload_end();
}
if (error) {
- mem_cgroup_uncharge_cache_page(page);
+ mem_cgroup_cancel_charge(page, memcg);
goto decused;
}
+ mem_cgroup_commit_charge(page, memcg, false);
lru_cache_add_anon(page);

spin_lock(&info->lock);
diff --git a/mm/swap.c b/mm/swap.c
index 9e8e3472248b..a98f48626359 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -695,6 +695,40 @@ void add_page_to_unevictable_list(struct page *page)
spin_unlock_irq(&zone->lru_lock);
}

+/**
+ * lru_cache_add_active_or_unevictable
+ * @page: the page to be added to LRU
+ * @vma: vma in which page is mapped for determining reclaimability
+ *
+ * Place @page on the active or unevictable LRU list, depending on its
+ * evictability. Note that if the page is not evictable, it goes
+ * directly back onto it's zone's unevictable list, it does NOT use a
+ * per cpu pagevec.
+ */
+void lru_cache_add_active_or_unevictable(struct page *page,
+ struct vm_area_struct *vma)
+{
+ VM_BUG_ON_PAGE(PageLRU(page), page);
+
+ if (likely((vma->vm_flags & (VM_LOCKED | VM_SPECIAL)) != VM_LOCKED)) {
+ SetPageActive(page);
+ lru_cache_add(page);
+ return;
+ }
+
+ if (!TestSetPageMlocked(page)) {
+ /*
+ * We use the irq-unsafe __mod_zone_page_stat because this
+ * counter is not modified from interrupt context, and the pte
+ * lock is held(spinlock), which implies preemption disabled.
+ */
+ __mod_zone_page_state(page_zone(page), NR_MLOCK,
+ hpage_nr_pages(page));
+ count_vm_event(UNEVICTABLE_PGMLOCKED);
+ }
+ add_page_to_unevictable_list(page);
+}
+
/*
* If the page can not be invalidated, it is moved to the
* inactive list to speed up its reclaim. It is moved to the
diff --git a/mm/swapfile.c b/mm/swapfile.c
index beeeef8a1b2d..3882fcb04ad9 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -1129,15 +1129,14 @@ static int unuse_pte(struct vm_area_struct *vma, pmd_t *pmd,
if (unlikely(!page))
return -ENOMEM;

- if (mem_cgroup_try_charge_swapin(vma->vm_mm, page,
- GFP_KERNEL, &memcg)) {
+ if (mem_cgroup_try_charge(page, vma->vm_mm, GFP_KERNEL, &memcg)) {
ret = -ENOMEM;
goto out_nolock;
}

pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
if (unlikely(!maybe_same_pte(*pte, swp_entry_to_pte(entry)))) {
- mem_cgroup_cancel_charge_swapin(memcg);
+ mem_cgroup_cancel_charge(page, memcg);
ret = 0;
goto out;
}
@@ -1147,11 +1146,14 @@ static int unuse_pte(struct vm_area_struct *vma, pmd_t *pmd,
get_page(page);
set_pte_at(vma->vm_mm, addr, pte,
pte_mkold(mk_pte(page, vma->vm_page_prot)));
- if (page == swapcache)
+ if (page == swapcache) {
page_add_anon_rmap(page, vma, addr);
- else /* ksm created a completely new copy */
+ mem_cgroup_commit_charge(page, memcg, true);
+ } else { /* ksm created a completely new copy */
page_add_new_anon_rmap(page, vma, addr);
- mem_cgroup_commit_charge_swapin(page, memcg);
+ mem_cgroup_commit_charge(page, memcg, false);
+ lru_cache_add_active_or_unevictable(page, vma);
+ }
swap_free(entry);
/*
* Move the page to the active list so it is not
--
1.9.3

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