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
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.
};
#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 *);
#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)
{
}
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);
/* For mmu_notifiers */
const unsigned long mmun_start = addr;
const unsigned long mmun_end = addr + PAGE_SIZE;
+ struct mem_cgroup *memcg;
+
+ err = mem_cgroup_try_charge(kpage, vma->vm_mm, GFP_KERNEL, &memcg);
+ if (err)
+ return err;
/* For try_to_free_swap() and munlock_vma_page() below */
lock_page(page);
get_page(kpage);
page_add_new_anon_rmap(kpage, vma, addr);
+ mem_cgroup_commit_charge(kpage, memcg, false);
+ lru_cache_add_active_or_unevictable(kpage, vma);
if (!PageAnon(page)) {
dec_mm_counter(mm, MM_FILEPAGES);
err = 0;
unlock:
+ mem_cgroup_cancel_charge(kpage, memcg);
mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
unlock_page(page);
return err;
if (!new_page)
goto put_old;
- if (mem_cgroup_charge_anon(new_page, mm, GFP_KERNEL))
- goto put_new;
-
__SetPageUptodate(new_page);
copy_highpage(new_page, old_page);
copy_to_page(new_page, vaddr, &opcode, UPROBE_SWBP_INSN_SIZE);
ret = __replace_page(vma, vaddr, old_page, new_page);
- if (ret)
- mem_cgroup_uncharge_page(new_page);
-
-put_new:
page_cache_release(new_page);
put_old:
put_page(old_page);
#include <linux/security.h>
#include <linux/cpuset.h>
#include <linux/hardirq.h> /* for BUG_ON(!in_atomic()) only */
+#include <linux/hugetlb.h>
#include <linux/memcontrol.h>
#include <linux/cleancache.h>
#include <linux/rmap.h>
pgoff_t offset, gfp_t gfp_mask,
void **shadowp)
{
+ int huge = PageHuge(page);
+ 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);
- if (error)
- return error;
+ if (!huge) {
+ 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);
+ if (!huge)
+ mem_cgroup_cancel_charge(page, memcg);
return error;
}
goto err_insert;
__inc_zone_page_state(page, NR_FILE_PAGES);
spin_unlock_irq(&mapping->tree_lock);
+ if (!huge)
+ 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);
+ if (!huge)
+ mem_cgroup_cancel_charge(page, memcg);
page_cache_release(page);
return error;
}
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_TRANSHUGE, &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);
/*
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 {
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);
count_vm_event(THP_FAULT_FALLBACK);
return VM_FAULT_FALLBACK;
}
- if (unlikely(mem_cgroup_charge_anon(page, mm, GFP_TRANSHUGE))) {
- 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;
struct page *page,
unsigned long haddr)
{
+ struct mem_cgroup *memcg;
spinlock_t *ptl;
pgtable_t pgtable;
pmd_t _pmd;
__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++) {
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);
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;
}
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 */
goto out;
}
- if (unlikely(mem_cgroup_charge_anon(new_page, mm, GFP_TRANSHUGE))) {
+ if (unlikely(mem_cgroup_try_charge(new_page, mm,
+ GFP_TRANSHUGE, &memcg))) {
put_page(new_page);
if (page) {
split_huge_page(page);
put_user_huge_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 {
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) {
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 */
if (!new_page)
return;
- if (unlikely(mem_cgroup_charge_anon(new_page, mm, GFP_TRANSHUGE)))
+ if (unlikely(mem_cgroup_try_charge(new_page, mm,
+ GFP_TRANSHUGE, &memcg)))
return;
/*
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);
return;
out:
- mem_cgroup_uncharge_page(new_page);
+ mem_cgroup_cancel_charge(new_page, memcg);
goto out_up_write;
}
return NOTIFY_OK;
}
-/**
- * mem_cgroup_try_charge - try charging a memcg
- * @memcg: memcg to charge
- * @nr_pages: number of pages to charge
- *
- * 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)
+static int try_charge(struct mem_cgroup *memcg, gfp_t gfp_mask,
+ unsigned int nr_pages)
{
unsigned int batch = max(CHARGE_BATCH, nr_pages);
int nr_retries = MEM_CGROUP_RECLAIM_RETRIES;
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)
-
-{
- struct mem_cgroup *memcg;
- int ret;
-
- memcg = get_mem_cgroup_from_mm(mm);
- ret = mem_cgroup_try_charge(memcg, gfp_mask, nr_pages);
- 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;
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);
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);
if (ret)
return ret;
- ret = mem_cgroup_try_charge(memcg, gfp, size >> PAGE_SHIFT);
+ ret = try_charge(memcg, gfp, size >> PAGE_SHIFT);
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);
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;
-
- 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);
- }
-
- memcg = mem_cgroup_try_charge_mm(mm, gfp_mask, nr_pages);
- 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);
- 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);
- 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);
- 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)
struct mem_cgroup *memcg = NULL;
unsigned int nr_pages = 1;
struct page_cgroup *pc;
- enum charge_type ctype;
*memcgp = NULL;
* 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*/
{
struct mem_cgroup *memcg = NULL;
struct page_cgroup *pc;
- enum charge_type type = MEM_CGROUP_CHARGE_TYPE_CACHE;
if (mem_cgroup_disabled())
return;
* 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
int ret;
/* Try a single bulk charge without reclaim first */
- ret = mem_cgroup_try_charge(mc.to, GFP_KERNEL & ~__GFP_WAIT, count);
+ ret = try_charge(mc.to, GFP_KERNEL & ~__GFP_WAIT, count);
if (!ret) {
mc.precharge += count;
return ret;
}
if (ret == -EINTR) {
- __mem_cgroup_cancel_charge(root_mem_cgroup, count);
+ cancel_charge(root_mem_cgroup, count);
return ret;
}
/* Try charges one by one with reclaim */
while (count--) {
- ret = mem_cgroup_try_charge(mc.to,
- GFP_KERNEL & ~__GFP_NORETRY, 1);
+ ret = try_charge(mc.to, GFP_KERNEL & ~__GFP_NORETRY, 1);
/*
* In case of failure, any residual charges against
* mc.to will be dropped by mem_cgroup_clear_mc()
* 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++;
/* 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;
}
/*
* 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 */
}
#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;
+ 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);
+ }
+
+ 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);
+
+ 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.
*
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) {
}
__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;
*/
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
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);
{
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;
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;
}
* 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);
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))
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);
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;
*/
__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);
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);
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:
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;
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;
}
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;
}
__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);
}
/**
radswap = swp_to_radix_entry(swap);
index = radix_tree_locate_item(&mapping->page_tree, radswap);
if (index == -1)
- return 0;
+ return -EAGAIN; /* tell shmem_unuse we found nothing */
/*
* Move _head_ to start search for next from here.
spin_unlock(&info->lock);
swap_free(swap);
}
- error = 1; /* not an error, but entry was found */
}
return error;
}
{
struct list_head *this, *next;
struct shmem_inode_info *info;
- int found = 0;
+ struct mem_cgroup *memcg;
int error = 0;
/*
* 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 */
+ error = -EAGAIN;
mutex_lock(&shmem_swaplist_mutex);
list_for_each_safe(this, next, &shmem_swaplist) {
info = list_entry(this, struct shmem_inode_info, swaplist);
if (info->swapped)
- found = shmem_unuse_inode(info, swap, &page);
+ error = shmem_unuse_inode(info, swap, &page);
else
list_del_init(&info->swaplist);
cond_resched();
- if (found)
+ if (error != -EAGAIN)
break;
+ /* found nothing in this: move on to search the next */
}
mutex_unlock(&shmem_swaplist_mutex);
- if (found < 0)
- error = found;
+ if (error) {
+ if (error != -ENOMEM)
+ error = 0;
+ mem_cgroup_cancel_charge(page, memcg);
+ } else
+ mem_cgroup_commit_charge(page, memcg, true);
out:
unlock_page(page);
page_cache_release(page);
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;
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,
swp_to_radix_entry(swap));
* 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);
if (sgp == SGP_WRITE)
__SetPageReferenced(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);
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);
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
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;
}
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