diff options
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/filemap.c | 12 | ||||
| -rw-r--r-- | mm/memcontrol.c | 166 | ||||
| -rw-r--r-- | mm/memory.c | 47 | ||||
| -rw-r--r-- | mm/migrate.c | 6 | ||||
| -rw-r--r-- | mm/page_alloc.c | 3 | ||||
| -rw-r--r-- | mm/rmap.c | 17 | ||||
| -rw-r--r-- | mm/swap_state.c | 10 | ||||
| -rw-r--r-- | mm/swapfile.c | 41 |
8 files changed, 275 insertions, 27 deletions
diff --git a/mm/filemap.c b/mm/filemap.c index 81fb9bf..b7a01e9 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -33,6 +33,7 @@ #include <linux/syscalls.h> #include <linux/cpuset.h> #include <linux/hardirq.h> /* for BUG_ON(!in_atomic()) only */ +#include <linux/memcontrol.h> #include "internal.h" /* @@ -118,6 +119,7 @@ void __remove_from_page_cache(struct page *page) { struct address_space *mapping = page->mapping; + mem_cgroup_uncharge_page(page); radix_tree_delete(&mapping->page_tree, page->index); page->mapping = NULL; mapping->nrpages--; @@ -461,6 +463,11 @@ int add_to_page_cache(struct page *page, struct address_space *mapping, int error = radix_tree_preload(gfp_mask & ~__GFP_HIGHMEM); if (error == 0) { + + error = mem_cgroup_charge(page, current->mm); + if (error) + goto out; + write_lock_irq(&mapping->tree_lock); error = radix_tree_insert(&mapping->page_tree, offset, page); if (!error) { @@ -470,10 +477,13 @@ int add_to_page_cache(struct page *page, struct address_space *mapping, page->index = offset; mapping->nrpages++; __inc_zone_page_state(page, NR_FILE_PAGES); - } + } else + mem_cgroup_uncharge_page(page); + write_unlock_irq(&mapping->tree_lock); radix_tree_preload_end(); } +out: return error; } EXPORT_SYMBOL(add_to_page_cache); diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 4d4805e..ebca767 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -21,6 +21,9 @@ #include <linux/memcontrol.h> #include <linux/cgroup.h> #include <linux/mm.h> +#include <linux/page-flags.h> +#include <linux/bit_spinlock.h> +#include <linux/rcupdate.h> struct cgroup_subsys mem_cgroup_subsys; @@ -31,7 +34,9 @@ struct cgroup_subsys mem_cgroup_subsys; * to help the administrator determine what knobs to tune. * * TODO: Add a water mark for the memory controller. Reclaim will begin when - * we hit the water mark. + * we hit the water mark. May be even add a low water mark, such that + * no reclaim occurs from a cgroup at it's low water mark, this is + * a feature that will be implemented much later in the future. */ struct mem_cgroup { struct cgroup_subsys_state css; @@ -49,6 +54,14 @@ struct mem_cgroup { }; /* + * We use the lower bit of the page->page_cgroup pointer as a bit spin + * lock. We need to ensure that page->page_cgroup is atleast two + * byte aligned (based on comments from Nick Piggin) + */ +#define PAGE_CGROUP_LOCK_BIT 0x0 +#define PAGE_CGROUP_LOCK (1 << PAGE_CGROUP_LOCK_BIT) + +/* * A page_cgroup page is associated with every page descriptor. The * page_cgroup helps us identify information about the cgroup */ @@ -56,6 +69,8 @@ struct page_cgroup { struct list_head lru; /* per cgroup LRU list */ struct page *page; struct mem_cgroup *mem_cgroup; + atomic_t ref_cnt; /* Helpful when pages move b/w */ + /* mapped and cached states */ }; @@ -88,14 +103,157 @@ void mm_free_cgroup(struct mm_struct *mm) css_put(&mm->mem_cgroup->css); } +static inline int page_cgroup_locked(struct page *page) +{ + return bit_spin_is_locked(PAGE_CGROUP_LOCK_BIT, + &page->page_cgroup); +} + void page_assign_page_cgroup(struct page *page, struct page_cgroup *pc) { - page->page_cgroup = (unsigned long)pc; + int locked; + + /* + * While resetting the page_cgroup we might not hold the + * page_cgroup lock. free_hot_cold_page() is an example + * of such a scenario + */ + if (pc) + VM_BUG_ON(!page_cgroup_locked(page)); + locked = (page->page_cgroup & PAGE_CGROUP_LOCK); + page->page_cgroup = ((unsigned long)pc | locked); } struct page_cgroup *page_get_page_cgroup(struct page *page) { - return page->page_cgroup; + return (struct page_cgroup *) + (page->page_cgroup & ~PAGE_CGROUP_LOCK); +} + +void __always_inline lock_page_cgroup(struct page *page) +{ + bit_spin_lock(PAGE_CGROUP_LOCK_BIT, &page->page_cgroup); + VM_BUG_ON(!page_cgroup_locked(page)); +} + +void __always_inline unlock_page_cgroup(struct page *page) +{ + bit_spin_unlock(PAGE_CGROUP_LOCK_BIT, &page->page_cgroup); +} + +/* + * Charge the memory controller for page usage. + * Return + * 0 if the charge was successful + * < 0 if the cgroup is over its limit + */ +int mem_cgroup_charge(struct page *page, struct mm_struct *mm) +{ + struct mem_cgroup *mem; + struct page_cgroup *pc, *race_pc; + + /* + * Should page_cgroup's go to their own slab? + * One could optimize the performance of the charging routine + * by saving a bit in the page_flags and using it as a lock + * to see if the cgroup page already has a page_cgroup associated + * with it + */ + lock_page_cgroup(page); + pc = page_get_page_cgroup(page); + /* + * The page_cgroup exists and the page has already been accounted + */ + if (pc) { + atomic_inc(&pc->ref_cnt); + goto done; + } + + unlock_page_cgroup(page); + + pc = kzalloc(sizeof(struct page_cgroup), GFP_KERNEL); + if (pc == NULL) + goto err; + + rcu_read_lock(); + /* + * We always charge the cgroup the mm_struct belongs to + * the mm_struct's mem_cgroup changes on task migration if the + * thread group leader migrates. It's possible that mm is not + * set, if so charge the init_mm (happens for pagecache usage). + */ + if (!mm) + mm = &init_mm; + + mem = rcu_dereference(mm->mem_cgroup); + /* + * For every charge from the cgroup, increment reference + * count + */ + css_get(&mem->css); + rcu_read_unlock(); + + /* + * If we created the page_cgroup, we should free it on exceeding + * the cgroup limit. + */ + if (res_counter_charge(&mem->res, 1)) { + css_put(&mem->css); + goto free_pc; + } + + lock_page_cgroup(page); + /* + * Check if somebody else beat us to allocating the page_cgroup + */ + race_pc = page_get_page_cgroup(page); + if (race_pc) { + kfree(pc); + pc = race_pc; + atomic_inc(&pc->ref_cnt); + res_counter_uncharge(&mem->res, 1); + css_put(&mem->css); + goto done; + } + + atomic_set(&pc->ref_cnt, 1); + pc->mem_cgroup = mem; + pc->page = page; + page_assign_page_cgroup(page, pc); + +done: + unlock_page_cgroup(page); + return 0; +free_pc: + kfree(pc); + return -ENOMEM; +err: + unlock_page_cgroup(page); + return -ENOMEM; +} + +/* + * Uncharging is always a welcome operation, we never complain, simply + * uncharge. + */ +void mem_cgroup_uncharge(struct page_cgroup *pc) +{ + struct mem_cgroup *mem; + struct page *page; + + if (!pc) + return; + + if (atomic_dec_and_test(&pc->ref_cnt)) { + page = pc->page; + lock_page_cgroup(page); + mem = pc->mem_cgroup; + css_put(&mem->css); + page_assign_page_cgroup(page, NULL); + unlock_page_cgroup(page); + res_counter_uncharge(&mem->res, 1); + kfree(pc); + } } static ssize_t mem_cgroup_read(struct cgroup *cont, struct cftype *cft, @@ -150,6 +308,8 @@ mem_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cont) return NULL; res_counter_init(&mem->res); + INIT_LIST_HEAD(&mem->active_list); + INIT_LIST_HEAD(&mem->inactive_list); return &mem->css; } diff --git a/mm/memory.c b/mm/memory.c index 9d073fa..0ba224e 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -50,6 +50,7 @@ #include <linux/delayacct.h> #include <linux/init.h> #include <linux/writeback.h> +#include <linux/memcontrol.h> #include <asm/pgalloc.h> #include <asm/uaccess.h> @@ -1144,16 +1145,20 @@ static int insert_page(struct mm_struct *mm, unsigned long addr, struct page *pa { int retval; pte_t *pte; - spinlock_t *ptl; + spinlock_t *ptl; + + retval = mem_cgroup_charge(page, mm); + if (retval) + goto out; retval = -EINVAL; if (PageAnon(page)) - goto out; + goto out_uncharge; retval = -ENOMEM; flush_dcache_page(page); pte = get_locked_pte(mm, addr, &ptl); if (!pte) - goto out; + goto out_uncharge; retval = -EBUSY; if (!pte_none(*pte)) goto out_unlock; @@ -1165,8 +1170,12 @@ static int insert_page(struct mm_struct *mm, unsigned long addr, struct page *pa set_pte_at(mm, addr, pte, mk_pte(page, prot)); retval = 0; + pte_unmap_unlock(pte, ptl); + return retval; out_unlock: pte_unmap_unlock(pte, ptl); +out_uncharge: + mem_cgroup_uncharge_page(page); out: return retval; } @@ -1641,6 +1650,9 @@ gotten: cow_user_page(new_page, old_page, address, vma); __SetPageUptodate(new_page); + if (mem_cgroup_charge(new_page, mm)) + goto oom_free_new; + /* * Re-check the pte - we dropped the lock */ @@ -1672,7 +1684,9 @@ gotten: /* Free the old page.. */ new_page = old_page; ret |= VM_FAULT_WRITE; - } + } else + mem_cgroup_uncharge_page(new_page); + if (new_page) page_cache_release(new_page); if (old_page) @@ -1696,6 +1710,8 @@ unlock: put_page(dirty_page); } return ret; +oom_free_new: + __free_page(new_page); oom: if (old_page) page_cache_release(old_page); @@ -2036,6 +2052,12 @@ static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma, count_vm_event(PGMAJFAULT); } + if (mem_cgroup_charge(page, mm)) { + delayacct_clear_flag(DELAYACCT_PF_SWAPIN); + ret = VM_FAULT_OOM; + goto out; + } + mark_page_accessed(page); lock_page(page); delayacct_clear_flag(DELAYACCT_PF_SWAPIN); @@ -2073,8 +2095,10 @@ static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma, if (write_access) { /* XXX: We could OR the do_wp_page code with this one? */ if (do_wp_page(mm, vma, address, - page_table, pmd, ptl, pte) & VM_FAULT_OOM) + page_table, pmd, ptl, pte) & VM_FAULT_OOM) { + mem_cgroup_uncharge_page(page); ret = VM_FAULT_OOM; + } goto out; } @@ -2085,6 +2109,7 @@ unlock: out: return ret; out_nomap: + mem_cgroup_uncharge_page(page); pte_unmap_unlock(page_table, ptl); unlock_page(page); page_cache_release(page); @@ -2114,6 +2139,9 @@ static int do_anonymous_page(struct mm_struct *mm, struct vm_area_struct *vma, goto oom; __SetPageUptodate(page); + if (mem_cgroup_charge(page, mm)) + goto oom_free_page; + entry = mk_pte(page, vma->vm_page_prot); entry = maybe_mkwrite(pte_mkdirty(entry), vma); @@ -2131,8 +2159,11 @@ unlock: pte_unmap_unlock(page_table, ptl); return 0; release: + mem_cgroup_uncharge_page(page); page_cache_release(page); goto unlock; +oom_free_page: + __free_page(page); oom: return VM_FAULT_OOM; } @@ -2246,6 +2277,11 @@ static int __do_fault(struct mm_struct *mm, struct vm_area_struct *vma, } + if (mem_cgroup_charge(page, mm)) { + ret = VM_FAULT_OOM; + goto out; + } + page_table = pte_offset_map_lock(mm, pmd, address, &ptl); /* @@ -2281,6 +2317,7 @@ static int __do_fault(struct mm_struct *mm, struct vm_area_struct *vma, /* no need to invalidate: a not-present page won't be cached */ update_mmu_cache(vma, address, entry); } else { + mem_cgroup_uncharge_page(page); if (anon) page_cache_release(page); else diff --git a/mm/migrate.c b/mm/migrate.c index 857a987..417bbda 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -29,6 +29,7 @@ #include <linux/mempolicy.h> #include <linux/vmalloc.h> #include <linux/security.h> +#include <linux/memcontrol.h> #include "internal.h" @@ -152,6 +153,11 @@ static void remove_migration_pte(struct vm_area_struct *vma, return; } + if (mem_cgroup_charge(new, mm)) { + pte_unmap(ptep); + return; + } + ptl = pte_lockptr(mm, pmd); spin_lock(ptl); pte = *ptep; diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 37576b8..26a54a1 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -43,6 +43,7 @@ #include <linux/backing-dev.h> #include <linux/fault-inject.h> #include <linux/page-isolation.h> +#include <linux/memcontrol.h> #include <asm/tlbflush.h> #include <asm/div64.h> @@ -987,6 +988,7 @@ static void free_hot_cold_page(struct page *page, int cold) if (!PageHighMem(page)) debug_check_no_locks_freed(page_address(page), PAGE_SIZE); + VM_BUG_ON(page_get_page_cgroup(page)); arch_free_page(page, 0); kernel_map_pages(page, 1, 0); @@ -2525,6 +2527,7 @@ void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone, set_page_links(page, zone, nid, pfn); init_page_count(page); reset_page_mapcount(page); + page_assign_page_cgroup(page, NULL); SetPageReserved(page); /* @@ -48,6 +48,7 @@ #include <linux/rcupdate.h> #include <linux/module.h> #include <linux/kallsyms.h> +#include <linux/memcontrol.h> #include <asm/tlbflush.h> @@ -554,8 +555,14 @@ void page_add_anon_rmap(struct page *page, VM_BUG_ON(address < vma->vm_start || address >= vma->vm_end); if (atomic_inc_and_test(&page->_mapcount)) __page_set_anon_rmap(page, vma, address); - else + else { __page_check_anon_rmap(page, vma, address); + /* + * We unconditionally charged during prepare, we uncharge here + * This takes care of balancing the reference counts + */ + mem_cgroup_uncharge_page(page); + } } /* @@ -586,6 +593,12 @@ void page_add_file_rmap(struct page *page) { if (atomic_inc_and_test(&page->_mapcount)) __inc_zone_page_state(page, NR_FILE_MAPPED); + else + /* + * We unconditionally charged during prepare, we uncharge here + * This takes care of balancing the reference counts + */ + mem_cgroup_uncharge_page(page); } #ifdef CONFIG_DEBUG_VM @@ -646,6 +659,8 @@ void page_remove_rmap(struct page *page, struct vm_area_struct *vma) page_clear_dirty(page); set_page_dirty(page); } + mem_cgroup_uncharge_page(page); + __dec_zone_page_state(page, PageAnon(page) ? NR_ANON_PAGES : NR_FILE_MAPPED); } diff --git a/mm/swap_state.c b/mm/swap_state.c index ec42f01..f96e3ff 100644 --- a/mm/swap_state.c +++ b/mm/swap_state.c @@ -17,6 +17,7 @@ #include <linux/backing-dev.h> #include <linux/pagevec.h> #include <linux/migrate.h> +#include <linux/memcontrol.h> #include <asm/pgtable.h> @@ -76,6 +77,11 @@ int add_to_swap_cache(struct page *page, swp_entry_t entry, gfp_t gfp_mask) BUG_ON(PagePrivate(page)); error = radix_tree_preload(gfp_mask); if (!error) { + + error = mem_cgroup_charge(page, current->mm); + if (error) + goto out; + write_lock_irq(&swapper_space.tree_lock); error = radix_tree_insert(&swapper_space.page_tree, entry.val, page); @@ -86,10 +92,13 @@ int add_to_swap_cache(struct page *page, swp_entry_t entry, gfp_t gfp_mask) total_swapcache_pages++; __inc_zone_page_state(page, NR_FILE_PAGES); INC_CACHE_INFO(add_total); + } else { + mem_cgroup_uncharge_page(page); } write_unlock_irq(&swapper_space.tree_lock); radix_tree_preload_end(); } +out: return error; } @@ -104,6 +113,7 @@ void __delete_from_swap_cache(struct page *page) BUG_ON(PageWriteback(page)); BUG_ON(PagePrivate(page)); + mem_cgroup_uncharge_page(page); radix_tree_delete(&swapper_space.page_tree, page_private(page)); set_page_private(page, 0); ClearPageSwapCache(page); diff --git a/mm/swapfile.c b/mm/swapfile.c index afae7b1..fddc4cc 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -27,6 +27,7 @@ #include <linux/mutex.h> #include <linux/capability.h> #include <linux/syscalls.h> +#include <linux/memcontrol.h> #include <asm/pgtable.h> #include <asm/tlbflush.h> @@ -506,9 +507,12 @@ unsigned int count_swap_pages(int type, int free) * just let do_wp_page work it out if a write is requested later - to * force COW, vm_page_prot omits write permission from any private vma. */ -static void unuse_pte(struct vm_area_struct *vma, pte_t *pte, +static int unuse_pte(struct vm_area_struct *vma, pte_t *pte, unsigned long addr, swp_entry_t entry, struct page *page) { + if (mem_cgroup_charge(page, vma->vm_mm)) + return -ENOMEM; + inc_mm_counter(vma->vm_mm, anon_rss); get_page(page); set_pte_at(vma->vm_mm, addr, pte, @@ -520,6 +524,7 @@ static void unuse_pte(struct vm_area_struct *vma, pte_t *pte, * immediately swapped out again after swapon. */ activate_page(page); + return 1; } static int unuse_pte_range(struct vm_area_struct *vma, pmd_t *pmd, @@ -529,7 +534,7 @@ static int unuse_pte_range(struct vm_area_struct *vma, pmd_t *pmd, pte_t swp_pte = swp_entry_to_pte(entry); pte_t *pte; spinlock_t *ptl; - int found = 0; + int ret = 0; pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); do { @@ -538,13 +543,12 @@ static int unuse_pte_range(struct vm_area_struct *vma, pmd_t *pmd, * Test inline before going to call unuse_pte. */ if (unlikely(pte_same(*pte, swp_pte))) { - unuse_pte(vma, pte++, addr, entry, page); - found = 1; + ret = unuse_pte(vma, pte++, addr, entry, page); break; } } while (pte++, addr += PAGE_SIZE, addr != end); pte_unmap_unlock(pte - 1, ptl); - return found; + return ret; } static inline int unuse_pmd_range(struct vm_area_struct *vma, pud_t *pud, @@ -553,14 +557,16 @@ static inline int unuse_pmd_range(struct vm_area_struct *vma, pud_t *pud, { pmd_t *pmd; unsigned long next; + int ret; pmd = pmd_offset(pud, addr); do { next = pmd_addr_end(addr, end); if (pmd_none_or_clear_bad(pmd)) continue; - if (unuse_pte_range(vma, pmd, addr, next, entry, page)) - return 1; + ret = unuse_pte_range(vma, pmd, addr, next, entry, page); + if (ret) + return ret; } while (pmd++, addr = next, addr != end); return 0; } @@ -571,14 +577,16 @@ static inline int unuse_pud_range(struct vm_area_struct *vma, pgd_t *pgd, { pud_t *pud; unsigned long next; + int ret; pud = pud_offset(pgd, addr); do { next = pud_addr_end(addr, end); if (pud_none_or_clear_bad(pud)) continue; - if (unuse_pmd_range(vma, pud, addr, next, entry, page)) - return 1; + ret = unuse_pmd_range(vma, pud, addr, next, entry, page); + if (ret) + return ret; } while (pud++, addr = next, addr != end); return 0; } @@ -588,6 +596,7 @@ static int unuse_vma(struct vm_area_struct *vma, { pgd_t *pgd; unsigned long addr, end, next; + int ret; if (page->mapping) { addr = page_address_in_vma(page, vma); @@ -605,8 +614,9 @@ static int unuse_vma(struct vm_area_struct *vma, next = pgd_addr_end(addr, end); if (pgd_none_or_clear_bad(pgd)) continue; - if (unuse_pud_range(vma, pgd, addr, next, entry, page)) - return 1; + ret = unuse_pud_range(vma, pgd, addr, next, entry, page); + if (ret) + return ret; } while (pgd++, addr = next, addr != end); return 0; } @@ -615,6 +625,7 @@ static int unuse_mm(struct mm_struct *mm, swp_entry_t entry, struct page *page) { struct vm_area_struct *vma; + int ret = 0; if (!down_read_trylock(&mm->mmap_sem)) { /* @@ -627,15 +638,11 @@ static int unuse_mm(struct mm_struct *mm, lock_page(page); } for (vma = mm->mmap; vma; vma = vma->vm_next) { - if (vma->anon_vma && unuse_vma(vma, entry, page)) + if (vma->anon_vma && (ret = unuse_vma(vma, entry, page))) break; } up_read(&mm->mmap_sem); - /* - * Currently unuse_mm cannot fail, but leave error handling - * at call sites for now, since we change it from time to time. - */ - return 0; + return (ret < 0)? ret: 0; } /* |
