diff options
Diffstat (limited to 'mm/memcontrol.c')
| -rw-r--r-- | mm/memcontrol.c | 155 |
1 files changed, 124 insertions, 31 deletions
diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 51ee96545579..f568b1964551 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -467,35 +467,31 @@ unsigned long mem_cgroup_isolate_pages(unsigned long nr_to_scan, return nr_taken; } -/* - * Charge the memory controller for page usage. - * Return - * 0 if the charge was successful - * < 0 if the cgroup is over its limit + +/** + * mem_cgroup_try_charge - get charge of PAGE_SIZE. + * @mm: an mm_struct which is charged against. (when *memcg is NULL) + * @gfp_mask: gfp_mask for reclaim. + * @memcg: a pointer to memory cgroup which is charged against. + * + * charge against memory cgroup pointed by *memcg. if *memcg == NULL, estimated + * memory cgroup from @mm is got and stored in *memcg. + * + * Returns 0 if success. -ENOMEM at failure. */ -static int mem_cgroup_charge_common(struct page *page, struct mm_struct *mm, - gfp_t gfp_mask, enum charge_type ctype, - struct mem_cgroup *memcg) + +int mem_cgroup_try_charge(struct mm_struct *mm, + gfp_t gfp_mask, struct mem_cgroup **memcg) { struct mem_cgroup *mem; - struct page_cgroup *pc; - unsigned long nr_retries = MEM_CGROUP_RECLAIM_RETRIES; - struct mem_cgroup_per_zone *mz; - unsigned long flags; - - pc = lookup_page_cgroup(page); - /* can happen at boot */ - if (unlikely(!pc)) - return 0; - prefetchw(pc); + int nr_retries = MEM_CGROUP_RECLAIM_RETRIES; /* * 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 (likely(!memcg)) { + if (likely(!*memcg)) { rcu_read_lock(); mem = mem_cgroup_from_task(rcu_dereference(mm->owner)); if (unlikely(!mem)) { @@ -506,15 +502,17 @@ static int mem_cgroup_charge_common(struct page *page, struct mm_struct *mm, * For every charge from the cgroup, increment reference count */ css_get(&mem->css); + *memcg = mem; rcu_read_unlock(); } else { - mem = memcg; - css_get(&memcg->css); + mem = *memcg; + css_get(&mem->css); } + while (unlikely(res_counter_charge(&mem->res, PAGE_SIZE))) { if (!(gfp_mask & __GFP_WAIT)) - goto out; + goto nomem; if (try_to_free_mem_cgroup_pages(mem, gfp_mask)) continue; @@ -531,18 +529,37 @@ static int mem_cgroup_charge_common(struct page *page, struct mm_struct *mm, if (!nr_retries--) { mem_cgroup_out_of_memory(mem, gfp_mask); - goto out; + goto nomem; } } + return 0; +nomem: + css_put(&mem->css); + return -ENOMEM; +} + +/* + * commit a charge got by mem_cgroup_try_charge() and makes page_cgroup to be + * USED state. If already USED, uncharge and return. + */ + +static void __mem_cgroup_commit_charge(struct mem_cgroup *mem, + struct page_cgroup *pc, + enum charge_type ctype) +{ + struct mem_cgroup_per_zone *mz; + unsigned long flags; + /* try_charge() can return NULL to *memcg, taking care of it. */ + if (!mem) + return; lock_page_cgroup(pc); if (unlikely(PageCgroupUsed(pc))) { unlock_page_cgroup(pc); res_counter_uncharge(&mem->res, PAGE_SIZE); css_put(&mem->css); - - goto done; + return; } pc->mem_cgroup = mem; /* @@ -557,15 +574,39 @@ static int mem_cgroup_charge_common(struct page *page, struct mm_struct *mm, __mem_cgroup_add_list(mz, pc); spin_unlock_irqrestore(&mz->lru_lock, flags); unlock_page_cgroup(pc); +} -done: +/* + * Charge the memory controller for page usage. + * Return + * 0 if the charge was successful + * < 0 if the cgroup is over its limit + */ +static int mem_cgroup_charge_common(struct page *page, struct mm_struct *mm, + gfp_t gfp_mask, enum charge_type ctype, + struct mem_cgroup *memcg) +{ + struct mem_cgroup *mem; + struct page_cgroup *pc; + int ret; + + pc = lookup_page_cgroup(page); + /* can happen at boot */ + if (unlikely(!pc)) + return 0; + prefetchw(pc); + + mem = memcg; + ret = mem_cgroup_try_charge(mm, gfp_mask, &mem); + if (ret) + return ret; + + __mem_cgroup_commit_charge(mem, pc, ctype); return 0; -out: - css_put(&mem->css); - return -ENOMEM; } -int mem_cgroup_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask) +int mem_cgroup_newpage_charge(struct page *page, + struct mm_struct *mm, gfp_t gfp_mask) { if (mem_cgroup_subsys.disabled) return 0; @@ -586,6 +627,34 @@ int mem_cgroup_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask) MEM_CGROUP_CHARGE_TYPE_MAPPED, NULL); } +/* + * same as mem_cgroup_newpage_charge(), now. + * But what we assume is different from newpage, and this is special case. + * treat this in special function. easy for maintenance. + */ + +int mem_cgroup_charge_migrate_fixup(struct page *page, + struct mm_struct *mm, gfp_t gfp_mask) +{ + if (mem_cgroup_subsys.disabled) + return 0; + + if (PageCompound(page)) + return 0; + + if (page_mapped(page) || (page->mapping && !PageAnon(page))) + return 0; + + if (unlikely(!mm)) + mm = &init_mm; + + return mem_cgroup_charge_common(page, mm, gfp_mask, + MEM_CGROUP_CHARGE_TYPE_MAPPED, NULL); +} + + + + int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask) { @@ -628,6 +697,30 @@ int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm, MEM_CGROUP_CHARGE_TYPE_SHMEM, NULL); } + +void mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *ptr) +{ + struct page_cgroup *pc; + + if (mem_cgroup_subsys.disabled) + return; + if (!ptr) + return; + pc = lookup_page_cgroup(page); + __mem_cgroup_commit_charge(ptr, pc, MEM_CGROUP_CHARGE_TYPE_MAPPED); +} + +void mem_cgroup_cancel_charge_swapin(struct mem_cgroup *mem) +{ + if (mem_cgroup_subsys.disabled) + return; + if (!mem) + return; + res_counter_uncharge(&mem->res, PAGE_SIZE); + css_put(&mem->css); +} + + /* * uncharge if !page_mapped(page) */ |