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.

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.

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.  Factor lru_cache_add_active_or_unevictable().

The order of functions in mm/memcontrol.c is entirely random, so this
new charge interface is implemented at the end of the file, where all
new or cleaned up, and documented code should go from now on.

Signed-off-by: Johannes Weiner <han...@cmpxchg.org>
---
 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                     |  51 ++-
 mm/memcontrol.c                      | 777 ++++++++++++++++-------------------
 mm/memory.c                          |  41 +-
 mm/migrate.c                         |   1 +
 mm/rmap.c                            |   5 -
 mm/shmem.c                           |  24 +-
 mm/swap.c                            |  20 +
 mm/swapfile.c                        |  14 +-
 13 files changed, 479 insertions(+), 552 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 b569b8be5c5a..5578b07376b7 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 *);
@@ -233,30 +216,22 @@ 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 350711560753..403a8530ee62 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -323,6 +323,9 @@ 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);
+
 /**
  * lru_cache_add: add a page to the page lists
  * @page: the page to add
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index 04709b66369d..44c508044c1d 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -180,6 +180,7 @@ 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 a82fbe4c9e8e..346c2e178193 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -558,19 +558,19 @@ 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;
        }
 
@@ -585,13 +585,14 @@ 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 64635f5278ff..1a22d8b12cf2 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;
@@ -968,13 +972,15 @@ 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();
@@ -982,6 +988,7 @@ static int do_huge_pmd_wp_page_fallback(struct mm_struct 
*mm,
                        ret |= VM_FAULT_OOM;
                        goto out;
                }
+               set_page_private(pages[i], (unsigned long)memcg);
        }
 
        for (i = 0; i < HPAGE_PMD_NR; i++) {
@@ -1010,7 +1017,11 @@ 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);
@@ -1036,7 +1047,9 @@ out_free_pages:
        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();
@@ -1050,6 +1063,7 @@ 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 +1115,7 @@ 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 +1144,7 @@ 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 +1153,8 @@ 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) {
@@ -2349,6 +2365,7 @@ 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 */
 
@@ -2359,7 +2376,7 @@ 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;
 
        /*
@@ -2448,6 +2465,8 @@ 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);
@@ -2461,7 +2480,7 @@ 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 d3961fce1d54..6f48e292ffe7 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -2574,163 +2574,6 @@ 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)
-{
-       unsigned int batch = max(CHARGE_BATCH, nr_pages);
-       int nr_retries = MEM_CGROUP_RECLAIM_RETRIES;
-       struct mem_cgroup *mem_over_limit;
-       struct res_counter *fail_res;
-       unsigned long nr_reclaimed;
-       unsigned long flags = 0;
-       unsigned long long size;
-       int ret = 0;
-
-retry:
-       if (consume_stock(memcg, nr_pages))
-               goto done;
-
-       size = batch * PAGE_SIZE;
-       if (!res_counter_charge(&memcg->res, size, &fail_res)) {
-               if (!do_swap_account)
-                       goto done_restock;
-               if (!res_counter_charge(&memcg->memsw, size, &fail_res))
-                       goto done_restock;
-               res_counter_uncharge(&memcg->res, size);
-               mem_over_limit = mem_cgroup_from_res_counter(fail_res, memsw);
-               flags |= MEM_CGROUP_RECLAIM_NOSWAP;
-       } else
-               mem_over_limit = mem_cgroup_from_res_counter(fail_res, res);
-
-       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(test_thread_flag(TIF_MEMDIE) ||
-                    fatal_signal_pending(current)))
-               goto bypass;
-
-       if (unlikely(task_in_memcg_oom(current)))
-               goto nomem;
-
-       if (!(gfp_mask & __GFP_WAIT))
-               goto nomem;
-
-       if (gfp_mask & __GFP_NORETRY)
-               goto nomem;
-
-       nr_reclaimed = mem_cgroup_reclaim(mem_over_limit, gfp_mask, flags);
-
-       if (mem_cgroup_margin(mem_over_limit) >= batch)
-               goto retry;
-       /*
-        * 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 && batch <= (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_NOFAIL)
-               goto bypass;
-
-       if (fatal_signal_pending(current))
-               goto bypass;
-
-       if (!oom)
-               goto nomem;
-
-       mem_cgroup_oom(mem_over_limit, gfp_mask, get_order(batch));
-nomem:
-       if (!(gfp_mask & __GFP_NOFAIL))
-               return -ENOMEM;
-bypass:
-       memcg = root_mem_cgroup;
-       ret = -EINTR;
-       goto retry;
-
-done_restock:
-       if (batch > nr_pages)
-               refill_stock(memcg, batch - nr_pages);
-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)
-{
-       unsigned long bytes = nr_pages * PAGE_SIZE;
-
-       res_counter_uncharge(&memcg->res, bytes);
-       if (do_swap_account)
-               res_counter_uncharge(&memcg->memsw, bytes);
-}
-
 /*
  * Cancel chrages in this cgroup....doesn't propagate to parent cgroup.
  * This is useful when moving usage to parent cgroup.
@@ -2788,69 +2631,6 @@ 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)
-{
-       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);
-       /*
-        * we don't need page_cgroup_lock about tail pages, becase they are not
-        * accessed by any other context at this point.
-        */
-
-       /*
-        * 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) {
-               zone = page_zone(page);
-               spin_lock_irq(&zone->lru_lock);
-               if (PageLRU(page)) {
-                       lruvec = mem_cgroup_zone_lruvec(zone, pc->mem_cgroup);
-                       ClearPageLRU(page);
-                       del_page_from_lru_list(page, lruvec, page_lru(page));
-                       was_on_lru = true;
-               }
-       }
-
-       pc->mem_cgroup = memcg;
-       SetPageCgroupUsed(pc);
-
-       if (lrucare) {
-               if (was_on_lru) {
-                       lruvec = mem_cgroup_zone_lruvec(zone, pc->mem_cgroup);
-                       VM_BUG_ON_PAGE(PageLRU(page), page);
-                       SetPageLRU(page);
-                       add_page_to_lru_list(page, lruvec, page_lru(page));
-               }
-               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);
-
-       /*
-        * "charge_statistics" updated event counter. Then, check it.
-        * Insert ancestor (and ancestor's ancestors), to softlimit RB-tree.
-        * if they exceeds softlimit.
-        */
-       memcg_check_events(memcg, page);
-}
-
 static DEFINE_MUTEX(set_limit_mutex);
 
 #ifdef CONFIG_MEMCG_KMEM
@@ -2895,6 +2675,9 @@ static int mem_cgroup_slabinfo_read(struct seq_file *m, 
void *v)
 }
 #endif
 
+static int try_charge(struct mem_cgroup *memcg, gfp_t gfp_mask,
+                     unsigned int nr_pages, bool oom);
+
 static int memcg_charge_kmem(struct mem_cgroup *memcg, gfp_t gfp, u64 size)
 {
        struct res_counter *fail_res;
@@ -2904,22 +2687,21 @@ 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);
@@ -3728,193 +3510,17 @@ static int mem_cgroup_move_parent(struct page *page,
        }
 
        ret = mem_cgroup_move_account(page, nr_pages,
-                               pc, child, parent);
-       if (!ret)
-               __mem_cgroup_cancel_local_charge(child, nr_pages);
-
-       if (nr_pages > 1)
-               compound_unlock_irqrestore(page, flags);
-       putback_lru_page(page);
-put:
-       put_page(page);
-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;
-       }
-
-       /*
-        * Page cache insertions can happen without an actual mm
-        * context, e.g. during disk probing on boot.
-        */
-       if (unlikely(!mm)) {
-               memcg = root_mem_cgroup;
-               ret = mem_cgroup_try_charge(memcg, gfp_mask, 1, true);
-               VM_BUG_ON(ret == -EINTR);
-               if (ret)
-                       return ret;
-       } else {
-               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;
+                               pc, child, parent);
+       if (!ret)
+               __mem_cgroup_cancel_local_charge(child, nr_pages);
+
+       if (nr_pages > 1)
+               compound_unlock_irqrestore(page, flags);
+       putback_lru_page(page);
+put:
+       put_page(page);
+out:
+       return ret;
 }
 
 static void mem_cgroup_do_uncharge(struct mem_cgroup *memcg,
@@ -4253,6 +3859,9 @@ static inline int 
mem_cgroup_move_swap_account(swp_entry_t entry,
 }
 #endif
 
+static void commit_charge(struct page *page, struct mem_cgroup *memcg,
+                         unsigned int nr_pages, bool anon, bool lrucare);
+
 /*
  * Before starting migration, account PAGE_SIZE to mem_cgroup that the old
  * page belongs to.
@@ -4263,7 +3872,6 @@ 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;
 
@@ -4325,16 +3933,12 @@ 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*/
@@ -4393,7 +3997,6 @@ 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;
@@ -4419,7 +4022,7 @@ 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
@@ -6434,6 +6037,7 @@ static void mem_cgroup_css_free(struct 
cgroup_subsys_state *css)
 #ifdef CONFIG_MMU
 /* Handlers for move charge at task migration. */
 #define PRECHARGE_COUNT_AT_ONCE        256
+static void cancel_charge(struct mem_cgroup *memcg, unsigned int nr_pages);
 static int mem_cgroup_do_precharge(unsigned long count)
 {
        int ret = 0;
@@ -6470,9 +6074,9 @@ 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);
                if (ret == -EINTR)
-                       __mem_cgroup_cancel_charge(root_mem_cgroup, 1);
+                       cancel_charge(root_mem_cgroup, 1);
                if (ret)
                        return ret;
                mc.precharge++;
@@ -6736,7 +6340,7 @@ 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;
        }
        /*
@@ -6744,7 +6348,7 @@ 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 */
@@ -7070,6 +6674,319 @@ static void __init enable_swap_cgroup(void)
 }
 #endif
 
+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;
+       struct mem_cgroup *mem_over_limit;
+       struct res_counter *fail_res;
+       unsigned long nr_reclaimed;
+       unsigned long flags = 0;
+       unsigned long long size;
+       int ret = 0;
+
+retry:
+       if (consume_stock(memcg, nr_pages))
+               goto done;
+
+       size = batch * PAGE_SIZE;
+       if (!res_counter_charge(&memcg->res, size, &fail_res)) {
+               if (!do_swap_account)
+                       goto done_restock;
+               if (!res_counter_charge(&memcg->memsw, size, &fail_res))
+                       goto done_restock;
+               res_counter_uncharge(&memcg->res, size);
+               mem_over_limit = mem_cgroup_from_res_counter(fail_res, memsw);
+               flags |= MEM_CGROUP_RECLAIM_NOSWAP;
+       } else
+               mem_over_limit = mem_cgroup_from_res_counter(fail_res, res);
+
+       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(test_thread_flag(TIF_MEMDIE) ||
+                    fatal_signal_pending(current)))
+               goto bypass;
+
+       if (unlikely(task_in_memcg_oom(current)))
+               goto nomem;
+
+       if (!(gfp_mask & __GFP_WAIT))
+               goto nomem;
+
+       if (gfp_mask & __GFP_NORETRY)
+               goto nomem;
+
+       nr_reclaimed = mem_cgroup_reclaim(mem_over_limit, gfp_mask, flags);
+
+       if (mem_cgroup_margin(mem_over_limit) >= batch)
+               goto retry;
+       /*
+        * 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 && batch <= (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_NOFAIL)
+               goto bypass;
+
+       if (fatal_signal_pending(current))
+               goto bypass;
+
+       if (!oom)
+               goto nomem;
+
+       mem_cgroup_oom(mem_over_limit, gfp_mask, get_order(batch));
+nomem:
+       if (!(gfp_mask & __GFP_NOFAIL))
+               return -ENOMEM;
+bypass:
+       memcg = root_mem_cgroup;
+       ret = -EINTR;
+       goto retry;
+
+done_restock:
+       if (batch > nr_pages)
+               refill_stock(memcg, batch - nr_pages);
+done:
+       return ret;
+}
+
+/**
+ * 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) {
+               /*
+                * Page cache insertions can happen without an actual
+                * mm context, e.g. during disk probing on boot.
+                */
+               if (unlikely(!mm)) {
+                       memcg = root_mem_cgroup;
+                       css_get(&memcg->css);
+               } else
+                       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;
+}
+
+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);
+       bool was_on_lru = false;
+       struct lruvec *lruvec;
+
+       lock_page_cgroup(pc);
+
+       VM_BUG_ON_PAGE(PageCgroupUsed(pc), page);
+       VM_BUG_ON_PAGE(PageLRU(page) && !lrucare, page);
+
+       if (lrucare) {
+               zone = page_zone(page);
+               spin_lock_irq(&zone->lru_lock);
+               if (PageLRU(page)) {
+                       lruvec = mem_cgroup_zone_lruvec(zone, pc->mem_cgroup);
+                       ClearPageLRU(page);
+                       del_page_from_lru_list(page, lruvec, page_lru(page));
+                       was_on_lru = true;
+               }
+       }
+
+       pc->mem_cgroup = memcg;
+       SetPageCgroupUsed(pc);
+
+       if (lrucare) {
+               if (was_on_lru) {
+                       lruvec = mem_cgroup_zone_lruvec(zone, pc->mem_cgroup);
+                       VM_BUG_ON_PAGE(PageLRU(page), page);
+                       SetPageLRU(page);
+                       add_page_to_lru_list(page, lruvec, page_lru(page));
+               }
+               spin_unlock_irq(&zone->lru_lock);
+       }
+
+       mem_cgroup_charge_statistics(memcg, page, anon, nr_pages);
+       unlock_page_cgroup(pc);
+
+       memcg_check_events(memcg, page);
+}
+
+/**
+ * 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);
+       }
+}
+
+static void cancel_charge(struct mem_cgroup *memcg, unsigned int nr_pages)
+{
+       unsigned long bytes = nr_pages * PAGE_SIZE;
+
+       res_counter_uncharge(&memcg->res, bytes);
+       if (do_swap_account)
+               res_counter_uncharge(&memcg->memsw, bytes);
+}
+
+/**
+ * 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 d0f0bef3be48..36af46a50fad 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -2673,6 +2673,7 @@ 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) {
@@ -2828,7 +2829,7 @@ 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;
@@ -2858,6 +2859,8 @@ 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
@@ -2895,7 +2898,7 @@ 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);
@@ -3031,10 +3034,10 @@ 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;
 
@@ -3110,7 +3113,7 @@ 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;
        }
@@ -3135,10 +3138,6 @@ 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);
@@ -3154,12 +3153,14 @@ 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))
@@ -3192,7 +3193,7 @@ 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);
@@ -3248,6 +3249,7 @@ 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;
@@ -3281,7 +3283,7 @@ 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);
@@ -3294,6 +3296,8 @@ 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);
 
@@ -3303,7 +3307,7 @@ 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:
@@ -3526,6 +3530,7 @@ 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;
@@ -3537,7 +3542,7 @@ 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;
        }
@@ -3557,12 +3562,14 @@ 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/migrate.c b/mm/migrate.c
index bed48809e5d0..a88fabd71f87 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -1853,6 +1853,7 @@ fail_putback:
         */
        flush_cache_range(vma, mmun_start, mmun_end);
        page_add_new_anon_rmap(new_page, vma, mmun_start);
+       lru_cache_add_active_or_unevictable(new_page, vma);
        pmdp_clear_flush(vma, mmun_start, pmd);
        set_pmd_at(mm, mmun_start, pmd, entry);
        flush_tlb_range(vma, mmun_start, mmun_end);
diff --git a/mm/rmap.c b/mm/rmap.c
index 9c3e77396d1a..6b6fe5f4ece1 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -1024,11 +1024,6 @@ 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);
-       if (!mlocked_vma_newpage(vma, page)) {
-               SetPageActive(page);
-               lru_cache_add(page);
-       } else
-               add_page_to_unevictable_list(page);
 }
 
 /**
diff --git a/mm/shmem.c b/mm/shmem.c
index 8f1a95406bae..f8637acc2dad 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 9ce43ba4498b..a5bdff331507 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -635,6 +635,26 @@ 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)
+{
+       if (!mlocked_vma_newpage(vma, page)) {
+               SetPageActive(page);
+               lru_cache_add(page);
+       } else
+               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 4a7f7e6992b6..7c57c7256c6e 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -1126,15 +1126,14 @@ 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;
        }
@@ -1144,11 +1143,14 @@ 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
-- 
1.9.2

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