diff options
Diffstat (limited to 'mm/memcontrol.c')
| -rw-r--r-- | mm/memcontrol.c | 172 |
1 files changed, 86 insertions, 86 deletions
diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 68d4890fc4bd..f227786e73db 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -2785,92 +2785,6 @@ void mem_cgroup_split_huge_fixup(struct page *head) } #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ -/** - * mem_cgroup_move_account - move account of the page - * @page: the page - * @nr_pages: number of regular pages (>1 for huge pages) - * @from: mem_cgroup which the page is moved from. - * @to: mem_cgroup which the page is moved to. @from != @to. - * - * The caller must confirm following. - * - page is not on LRU (isolate_page() is useful.) - * - compound_lock is held when nr_pages > 1 - * - * This function doesn't do "charge" to new cgroup and doesn't do "uncharge" - * from old cgroup. - */ -static int mem_cgroup_move_account(struct page *page, - unsigned int nr_pages, - struct mem_cgroup *from, - struct mem_cgroup *to) -{ - unsigned long flags; - int ret; - - VM_BUG_ON(from == to); - VM_BUG_ON_PAGE(PageLRU(page), page); - /* - * The page is isolated from LRU. So, collapse function - * will not handle this page. But page splitting can happen. - * Do this check under compound_page_lock(). The caller should - * hold it. - */ - ret = -EBUSY; - if (nr_pages > 1 && !PageTransHuge(page)) - goto out; - - /* - * Prevent mem_cgroup_migrate() from looking at page->mem_cgroup - * of its source page while we change it: page migration takes - * both pages off the LRU, but page cache replacement doesn't. - */ - if (!trylock_page(page)) - goto out; - - ret = -EINVAL; - if (page->mem_cgroup != from) - goto out_unlock; - - spin_lock_irqsave(&from->move_lock, flags); - - if (!PageAnon(page) && page_mapped(page)) { - __this_cpu_sub(from->stat->count[MEM_CGROUP_STAT_FILE_MAPPED], - nr_pages); - __this_cpu_add(to->stat->count[MEM_CGROUP_STAT_FILE_MAPPED], - nr_pages); - } - - if (PageWriteback(page)) { - __this_cpu_sub(from->stat->count[MEM_CGROUP_STAT_WRITEBACK], - nr_pages); - __this_cpu_add(to->stat->count[MEM_CGROUP_STAT_WRITEBACK], - nr_pages); - } - - /* - * It is safe to change page->mem_cgroup here because the page - * is referenced, charged, and isolated - we can't race with - * uncharging, charging, migration, or LRU putback. - */ - - /* caller should have done css_get */ - page->mem_cgroup = to; - spin_unlock_irqrestore(&from->move_lock, flags); - - ret = 0; - - local_irq_disable(); - mem_cgroup_charge_statistics(to, page, nr_pages); - memcg_check_events(to, page); - mem_cgroup_charge_statistics(from, page, -nr_pages); - memcg_check_events(from, page); - local_irq_enable(); -out_unlock: - unlock_page(page); -out: - return ret; -} - #ifdef CONFIG_MEMCG_SWAP static void mem_cgroup_swap_statistics(struct mem_cgroup *memcg, bool charge) @@ -4822,6 +4736,92 @@ static struct page *mc_handle_file_pte(struct vm_area_struct *vma, return page; } +/** + * mem_cgroup_move_account - move account of the page + * @page: the page + * @nr_pages: number of regular pages (>1 for huge pages) + * @from: mem_cgroup which the page is moved from. + * @to: mem_cgroup which the page is moved to. @from != @to. + * + * The caller must confirm following. + * - page is not on LRU (isolate_page() is useful.) + * - compound_lock is held when nr_pages > 1 + * + * This function doesn't do "charge" to new cgroup and doesn't do "uncharge" + * from old cgroup. + */ +static int mem_cgroup_move_account(struct page *page, + unsigned int nr_pages, + struct mem_cgroup *from, + struct mem_cgroup *to) +{ + unsigned long flags; + int ret; + + VM_BUG_ON(from == to); + VM_BUG_ON_PAGE(PageLRU(page), page); + /* + * The page is isolated from LRU. So, collapse function + * will not handle this page. But page splitting can happen. + * Do this check under compound_page_lock(). The caller should + * hold it. + */ + ret = -EBUSY; + if (nr_pages > 1 && !PageTransHuge(page)) + goto out; + + /* + * Prevent mem_cgroup_migrate() from looking at page->mem_cgroup + * of its source page while we change it: page migration takes + * both pages off the LRU, but page cache replacement doesn't. + */ + if (!trylock_page(page)) + goto out; + + ret = -EINVAL; + if (page->mem_cgroup != from) + goto out_unlock; + + spin_lock_irqsave(&from->move_lock, flags); + + if (!PageAnon(page) && page_mapped(page)) { + __this_cpu_sub(from->stat->count[MEM_CGROUP_STAT_FILE_MAPPED], + nr_pages); + __this_cpu_add(to->stat->count[MEM_CGROUP_STAT_FILE_MAPPED], + nr_pages); + } + + if (PageWriteback(page)) { + __this_cpu_sub(from->stat->count[MEM_CGROUP_STAT_WRITEBACK], + nr_pages); + __this_cpu_add(to->stat->count[MEM_CGROUP_STAT_WRITEBACK], + nr_pages); + } + + /* + * It is safe to change page->mem_cgroup here because the page + * is referenced, charged, and isolated - we can't race with + * uncharging, charging, migration, or LRU putback. + */ + + /* caller should have done css_get */ + page->mem_cgroup = to; + spin_unlock_irqrestore(&from->move_lock, flags); + + ret = 0; + + local_irq_disable(); + mem_cgroup_charge_statistics(to, page, nr_pages); + memcg_check_events(to, page); + mem_cgroup_charge_statistics(from, page, -nr_pages); + memcg_check_events(from, page); + local_irq_enable(); +out_unlock: + unlock_page(page); +out: + return ret; +} + static enum mc_target_type get_mctgt_type(struct vm_area_struct *vma, unsigned long addr, pte_t ptent, union mc_target *target) { |