X-Git-Url: https://git.karo-electronics.de/?a=blobdiff_plain;ds=sidebyside;f=mm%2Fmemcontrol.c;h=da53a252b259f0f36f553e9646187db18d49d76a;hb=493f3358cb289ccf716c5a14fa5bb52ab75943e5;hp=db76ef726293fa744da16ef8cabbe643980bf07e;hpb=fd3830b379b87b9a47d796d79d1e41f73e1973fa;p=mv-sheeva.git diff --git a/mm/memcontrol.c b/mm/memcontrol.c index db76ef72629..da53a252b25 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -612,8 +612,10 @@ static void mem_cgroup_charge_statistics(struct mem_cgroup *mem, /* pagein of a big page is an event. So, ignore page size */ if (nr_pages > 0) __this_cpu_inc(mem->stat->count[MEM_CGROUP_STAT_PGPGIN_COUNT]); - else + else { __this_cpu_inc(mem->stat->count[MEM_CGROUP_STAT_PGPGOUT_COUNT]); + nr_pages = -nr_pages; /* for event */ + } __this_cpu_add(mem->stat->count[MEM_CGROUP_EVENTS], nr_pages); @@ -1111,6 +1113,23 @@ static bool mem_cgroup_check_under_limit(struct mem_cgroup *mem) return false; } +/** + * mem_cgroup_check_margin - check if the memory cgroup allows charging + * @mem: memory cgroup to check + * @bytes: the number of bytes the caller intends to charge + * + * Returns a boolean value on whether @mem can be charged @bytes or + * whether this would exceed the limit. + */ +static bool mem_cgroup_check_margin(struct mem_cgroup *mem, unsigned long bytes) +{ + if (!res_counter_check_margin(&mem->res, bytes)) + return false; + if (do_swap_account && !res_counter_check_margin(&mem->memsw, bytes)) + return false; + return true; +} + static unsigned int get_swappiness(struct mem_cgroup *memcg) { struct cgroup *cgrp = memcg->css.cgroup; @@ -1832,27 +1851,39 @@ static int __mem_cgroup_do_charge(struct mem_cgroup *mem, gfp_t gfp_mask, if (likely(!ret)) return CHARGE_OK; + res_counter_uncharge(&mem->res, csize); mem_over_limit = mem_cgroup_from_res_counter(fail_res, memsw); flags |= MEM_CGROUP_RECLAIM_NOSWAP; } else mem_over_limit = mem_cgroup_from_res_counter(fail_res, res); - - if (csize > PAGE_SIZE) /* change csize and retry */ + /* + * csize can be either a huge page (HPAGE_SIZE), a batch of + * regular pages (CHARGE_SIZE), or a single regular page + * (PAGE_SIZE). + * + * Never reclaim on behalf of optional batching, retry with a + * single page instead. + */ + if (csize == CHARGE_SIZE) return CHARGE_RETRY; if (!(gfp_mask & __GFP_WAIT)) return CHARGE_WOULDBLOCK; ret = mem_cgroup_hierarchical_reclaim(mem_over_limit, NULL, - gfp_mask, flags); + gfp_mask, flags); + if (mem_cgroup_check_margin(mem_over_limit, csize)) + return CHARGE_RETRY; /* - * try_to_free_mem_cgroup_pages() might not give us a full - * picture of reclaim. Some pages are reclaimed and might be - * moved to swap cache or just unmapped from the cgroup. - * Check the limit again to see if the reclaim reduced the - * current usage of the cgroup before giving up + * Even though the limit is exceeded at this point, reclaim + * may have been able to free some pages. Retry the charge + * before killing the task. + * + * Only for regular pages, though: huge pages are rather + * unlikely to succeed so close to the limit, and we fall back + * to regular pages anyway in case of failure. */ - if (ret || mem_cgroup_check_under_limit(mem_over_limit)) + if (csize == PAGE_SIZE && ret) return CHARGE_RETRY; /* @@ -2144,6 +2175,8 @@ void mem_cgroup_split_huge_fixup(struct page *head, struct page *tail) struct page_cgroup *tail_pc = lookup_page_cgroup(tail); unsigned long flags; + if (mem_cgroup_disabled()) + return; /* * We have no races with charge/uncharge but will have races with * page state accounting. @@ -2233,7 +2266,12 @@ static int mem_cgroup_move_account(struct page_cgroup *pc, { int ret = -EINVAL; unsigned long flags; - + /* + * 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. + */ if ((charge_size > PAGE_SIZE) && !PageTransHuge(pc->page)) return -EBUSY; @@ -2265,7 +2303,7 @@ static int mem_cgroup_move_parent(struct page_cgroup *pc, struct cgroup *cg = child->css.cgroup; struct cgroup *pcg = cg->parent; struct mem_cgroup *parent; - int charge = PAGE_SIZE; + int page_size = PAGE_SIZE; unsigned long flags; int ret; @@ -2278,23 +2316,26 @@ static int mem_cgroup_move_parent(struct page_cgroup *pc, goto out; if (isolate_lru_page(page)) goto put; - /* The page is isolated from LRU and we have no race with splitting */ - charge = PAGE_SIZE << compound_order(page); + + if (PageTransHuge(page)) + page_size = HPAGE_SIZE; parent = mem_cgroup_from_cont(pcg); - ret = __mem_cgroup_try_charge(NULL, gfp_mask, &parent, false, charge); + ret = __mem_cgroup_try_charge(NULL, gfp_mask, + &parent, false, page_size); if (ret || !parent) goto put_back; - if (charge > PAGE_SIZE) + if (page_size > PAGE_SIZE) flags = compound_lock_irqsave(page); - ret = mem_cgroup_move_account(pc, child, parent, true, charge); + ret = mem_cgroup_move_account(pc, child, parent, true, page_size); if (ret) - mem_cgroup_cancel_charge(parent, charge); -put_back: - if (charge > PAGE_SIZE) + mem_cgroup_cancel_charge(parent, page_size); + + if (page_size > PAGE_SIZE) compound_unlock_irqrestore(page, flags); +put_back: putback_lru_page(page); put: put_page(page); @@ -2312,13 +2353,19 @@ static int mem_cgroup_charge_common(struct page *page, struct mm_struct *mm, gfp_t gfp_mask, enum charge_type ctype) { struct mem_cgroup *mem = NULL; + int page_size = PAGE_SIZE; struct page_cgroup *pc; + bool oom = true; int ret; - int page_size = PAGE_SIZE; if (PageTransHuge(page)) { page_size <<= compound_order(page); VM_BUG_ON(!PageTransHuge(page)); + /* + * Never OOM-kill a process for a huge page. The + * fault handler will fall back to regular pages. + */ + oom = false; } pc = lookup_page_cgroup(page); @@ -2327,7 +2374,7 @@ static int mem_cgroup_charge_common(struct page *page, struct mm_struct *mm, return 0; prefetchw(pc); - ret = __mem_cgroup_try_charge(mm, gfp_mask, &mem, true, page_size); + ret = __mem_cgroup_try_charge(mm, gfp_mask, &mem, oom, page_size); if (ret || !mem) return ret; @@ -5013,9 +5060,9 @@ struct cgroup_subsys mem_cgroup_subsys = { static int __init enable_swap_account(char *s) { /* consider enabled if no parameter or 1 is given */ - if (!s || !strcmp(s, "1")) + if (!(*s) || !strcmp(s, "=1")) really_do_swap_account = 1; - else if (!strcmp(s, "0")) + else if (!strcmp(s, "=0")) really_do_swap_account = 0; return 1; } @@ -5023,7 +5070,8 @@ __setup("swapaccount", enable_swap_account); static int __init disable_swap_account(char *s) { - enable_swap_account("0"); + printk_once("noswapaccount is deprecated and will be removed in 2.6.40. Use swapaccount=0 instead\n"); + enable_swap_account("=0"); return 1; } __setup("noswapaccount", disable_swap_account);