diff options
| -rw-r--r-- | Documentation/controllers/memory.txt | 5 | ||||
| -rw-r--r-- | include/linux/swap.h | 22 | ||||
| -rw-r--r-- | mm/memcontrol.c | 67 | ||||
| -rw-r--r-- | mm/shmem.c | 18 | ||||
| -rw-r--r-- | mm/swap_state.c | 1 |
5 files changed, 105 insertions, 8 deletions
diff --git a/Documentation/controllers/memory.txt b/Documentation/controllers/memory.txt index 54253b7a8db..9fe2d0eabe0 100644 --- a/Documentation/controllers/memory.txt +++ b/Documentation/controllers/memory.txt @@ -137,6 +137,11 @@ behind this approach is that a cgroup that aggressively uses a shared page will eventually get charged for it (once it is uncharged from the cgroup that brought it in -- this will happen on memory pressure). +Exception: When you do swapoff and make swapped-out pages of shmem(tmpfs) to +be backed into memory in force, charges for pages are accounted against the +caller of swapoff rather than the users of shmem. + + 2.4 Reclaim Each cgroup maintains a per cgroup LRU that consists of an active diff --git a/include/linux/swap.h b/include/linux/swap.h index 91dee50fe26..f8f3907533f 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -333,6 +333,22 @@ static inline void disable_swap_token(void) put_swap_token(swap_token_mm); } +#ifdef CONFIG_CGROUP_MEM_RES_CTLR +extern int mem_cgroup_cache_charge_swapin(struct page *page, + struct mm_struct *mm, gfp_t mask, bool locked); +extern void mem_cgroup_uncharge_swapcache(struct page *page); +#else +static inline +int mem_cgroup_cache_charge_swapin(struct page *page, + struct mm_struct *mm, gfp_t mask, bool locked) +{ + return 0; +} +static inline void mem_cgroup_uncharge_swapcache(struct page *page) +{ +} +#endif + #else /* CONFIG_SWAP */ #define nr_swap_pages 0L @@ -409,6 +425,12 @@ static inline swp_entry_t get_swap_page(void) #define has_swap_token(x) 0 #define disable_swap_token() do { } while(0) +static inline int mem_cgroup_cache_charge_swapin(struct page *page, + struct mm_struct *mm, gfp_t mask, bool locked) +{ + return 0; +} + #endif /* CONFIG_SWAP */ #endif /* __KERNEL__*/ #endif /* _LINUX_SWAP_H */ diff --git a/mm/memcontrol.c b/mm/memcontrol.c index decace3bb57..7288e9d85ca 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -21,6 +21,7 @@ #include <linux/memcontrol.h> #include <linux/cgroup.h> #include <linux/mm.h> +#include <linux/pagemap.h> #include <linux/smp.h> #include <linux/page-flags.h> #include <linux/backing-dev.h> @@ -139,6 +140,7 @@ enum charge_type { MEM_CGROUP_CHARGE_TYPE_MAPPED, MEM_CGROUP_CHARGE_TYPE_SHMEM, /* used by page migration of shmem */ MEM_CGROUP_CHARGE_TYPE_FORCE, /* used by force_empty */ + MEM_CGROUP_CHARGE_TYPE_SWAPOUT, /* for accounting swapcache */ NR_CHARGE_TYPE, }; @@ -780,6 +782,33 @@ int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm, MEM_CGROUP_CHARGE_TYPE_SHMEM, NULL); } +#ifdef CONFIG_SWAP +int mem_cgroup_cache_charge_swapin(struct page *page, + struct mm_struct *mm, gfp_t mask, bool locked) +{ + int ret = 0; + + if (mem_cgroup_subsys.disabled) + return 0; + if (unlikely(!mm)) + mm = &init_mm; + if (!locked) + lock_page(page); + /* + * If not locked, the page can be dropped from SwapCache until + * we reach here. + */ + if (PageSwapCache(page)) { + ret = mem_cgroup_charge_common(page, mm, mask, + MEM_CGROUP_CHARGE_TYPE_SHMEM, NULL); + } + if (!locked) + unlock_page(page); + + return ret; +} +#endif + void mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *ptr) { struct page_cgroup *pc; @@ -817,6 +846,9 @@ __mem_cgroup_uncharge_common(struct page *page, enum charge_type ctype) if (mem_cgroup_subsys.disabled) return; + if (PageSwapCache(page)) + return; + /* * Check if our page_cgroup is valid */ @@ -825,12 +857,26 @@ __mem_cgroup_uncharge_common(struct page *page, enum charge_type ctype) return; lock_page_cgroup(pc); - if ((ctype == MEM_CGROUP_CHARGE_TYPE_MAPPED && page_mapped(page)) - || !PageCgroupUsed(pc)) { - /* This happens at race in zap_pte_range() and do_swap_page()*/ - unlock_page_cgroup(pc); - return; + + if (!PageCgroupUsed(pc)) + goto unlock_out; + + switch (ctype) { + case MEM_CGROUP_CHARGE_TYPE_MAPPED: + if (page_mapped(page)) + goto unlock_out; + break; + case MEM_CGROUP_CHARGE_TYPE_SWAPOUT: + if (!PageAnon(page)) { /* Shared memory */ + if (page->mapping && !page_is_file_cache(page)) + goto unlock_out; + } else if (page_mapped(page)) /* Anon */ + goto unlock_out; + break; + default: + break; } + ClearPageCgroupUsed(pc); mem = pc->mem_cgroup; @@ -844,6 +890,10 @@ __mem_cgroup_uncharge_common(struct page *page, enum charge_type ctype) css_put(&mem->css); return; + +unlock_out: + unlock_page_cgroup(pc); + return; } void mem_cgroup_uncharge_page(struct page *page) @@ -863,6 +913,11 @@ void mem_cgroup_uncharge_cache_page(struct page *page) __mem_cgroup_uncharge_common(page, MEM_CGROUP_CHARGE_TYPE_CACHE); } +void mem_cgroup_uncharge_swapcache(struct page *page) +{ + __mem_cgroup_uncharge_common(page, MEM_CGROUP_CHARGE_TYPE_SWAPOUT); +} + /* * Before starting migration, account PAGE_SIZE to mem_cgroup that the old * page belongs to. @@ -920,7 +975,7 @@ void mem_cgroup_end_migration(struct mem_cgroup *mem, ctype = MEM_CGROUP_CHARGE_TYPE_SHMEM; /* unused page is not on radix-tree now. */ - if (unused && ctype != MEM_CGROUP_CHARGE_TYPE_MAPPED) + if (unused) __mem_cgroup_uncharge_common(unused, ctype); pc = lookup_page_cgroup(target); diff --git a/mm/shmem.c b/mm/shmem.c index bd9b4ea307b..adf5c3eedbc 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -928,8 +928,12 @@ found: error = 1; if (!inode) goto out; - /* Charge page using GFP_HIGHUSER_MOVABLE while we can wait */ - error = mem_cgroup_cache_charge(page, current->mm, GFP_HIGHUSER_MOVABLE); + /* + * Charge page using GFP_HIGHUSER_MOVABLE while we can wait. + * charged back to the user(not to caller) when swap account is used. + */ + error = mem_cgroup_cache_charge_swapin(page, + current->mm, GFP_HIGHUSER_MOVABLE, true); if (error) goto out; error = radix_tree_preload(GFP_KERNEL); @@ -1266,6 +1270,16 @@ repeat: goto repeat; } wait_on_page_locked(swappage); + /* + * We want to avoid charge at add_to_page_cache(). + * charge against this swap cache here. + */ + if (mem_cgroup_cache_charge_swapin(swappage, + current->mm, gfp, false)) { + page_cache_release(swappage); + error = -ENOMEM; + goto failed; + } page_cache_release(swappage); goto repeat; } diff --git a/mm/swap_state.c b/mm/swap_state.c index 81c825f67a7..09291ca11f5 100644 --- a/mm/swap_state.c +++ b/mm/swap_state.c @@ -118,6 +118,7 @@ void __delete_from_swap_cache(struct page *page) total_swapcache_pages--; __dec_zone_page_state(page, NR_FILE_PAGES); INC_CACHE_INFO(del_total); + mem_cgroup_uncharge_swapcache(page); } /** |