diff options
Diffstat (limited to 'mm/memcontrol.c')
-rw-r--r-- | mm/memcontrol.c | 104 |
1 files changed, 26 insertions, 78 deletions
diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 5f84d2351ddb..ebd1e86bef1c 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -35,7 +35,6 @@ #include <linux/limits.h> #include <linux/mutex.h> #include <linux/rbtree.h> -#include <linux/shmem_fs.h> #include <linux/slab.h> #include <linux/swap.h> #include <linux/swapops.h> @@ -1842,29 +1841,23 @@ static int mem_cgroup_hierarchical_reclaim(struct mem_cgroup *root_mem, */ static bool mem_cgroup_oom_lock(struct mem_cgroup *mem) { - int lock_count = -1; struct mem_cgroup *iter, *failed = NULL; bool cond = true; for_each_mem_cgroup_tree_cond(iter, mem, cond) { - bool locked = iter->oom_lock; - - iter->oom_lock = true; - if (lock_count == -1) - lock_count = iter->oom_lock; - else if (lock_count != locked) { + if (iter->oom_lock) { /* * this subtree of our hierarchy is already locked * so we cannot give a lock. */ - lock_count = 0; failed = iter; cond = false; - } + } else + iter->oom_lock = true; } if (!failed) - goto done; + return true; /* * OK, we failed to lock the whole subtree so we have to clean up @@ -1878,8 +1871,7 @@ static bool mem_cgroup_oom_lock(struct mem_cgroup *mem) } iter->oom_lock = false; } -done: - return lock_count; + return false; } /* @@ -2092,6 +2084,7 @@ struct memcg_stock_pcp { #define FLUSHING_CACHED_CHARGE (0) }; static DEFINE_PER_CPU(struct memcg_stock_pcp, memcg_stock); +static DEFINE_MUTEX(percpu_charge_mutex); /* * Try to consume stocked charge on this cpu. If success, one page is consumed @@ -2169,13 +2162,7 @@ static void drain_all_stock(struct mem_cgroup *root_mem, bool sync) /* Notify other cpus that system-wide "drain" is running */ get_online_cpus(); - /* - * Get a hint for avoiding draining charges on the current cpu, - * which must be exhausted by our charging. It is not required that - * this be a precise check, so we use raw_smp_processor_id() instead of - * getcpu()/putcpu(). - */ - curcpu = raw_smp_processor_id(); + curcpu = get_cpu(); for_each_online_cpu(cpu) { struct memcg_stock_pcp *stock = &per_cpu(memcg_stock, cpu); struct mem_cgroup *mem; @@ -2192,14 +2179,14 @@ static void drain_all_stock(struct mem_cgroup *root_mem, bool sync) schedule_work_on(cpu, &stock->work); } } + put_cpu(); if (!sync) goto out; for_each_online_cpu(cpu) { struct memcg_stock_pcp *stock = &per_cpu(memcg_stock, cpu); - if (mem_cgroup_same_or_subtree(root_mem, stock->cached) && - test_bit(FLUSHING_CACHED_CHARGE, &stock->flags)) + if (test_bit(FLUSHING_CACHED_CHARGE, &stock->flags)) flush_work(&stock->work); } out: @@ -2214,14 +2201,22 @@ out: */ static void drain_all_stock_async(struct mem_cgroup *root_mem) { + /* + * If someone calls draining, avoid adding more kworker runs. + */ + if (!mutex_trylock(&percpu_charge_mutex)) + return; drain_all_stock(root_mem, false); + mutex_unlock(&percpu_charge_mutex); } /* This is a synchronous drain interface. */ static void drain_all_stock_sync(struct mem_cgroup *root_mem) { /* called when force_empty is called */ + mutex_lock(&percpu_charge_mutex); drain_all_stock(root_mem, true); + mutex_unlock(&percpu_charge_mutex); } /* @@ -2873,30 +2868,6 @@ int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm, return 0; if (PageCompound(page)) return 0; - /* - * Corner case handling. This is called from add_to_page_cache() - * in usual. But some FS (shmem) precharges this page before calling it - * and call add_to_page_cache() with GFP_NOWAIT. - * - * For GFP_NOWAIT case, the page may be pre-charged before calling - * add_to_page_cache(). (See shmem.c) check it here and avoid to call - * charge twice. (It works but has to pay a bit larger cost.) - * And when the page is SwapCache, it should take swap information - * into account. This is under lock_page() now. - */ - if (!(gfp_mask & __GFP_WAIT)) { - struct page_cgroup *pc; - - pc = lookup_page_cgroup(page); - if (!pc) - return 0; - lock_page_cgroup(pc); - if (PageCgroupUsed(pc)) { - unlock_page_cgroup(pc); - return 0; - } - unlock_page_cgroup(pc); - } if (unlikely(!mm)) mm = &init_mm; @@ -3486,31 +3457,6 @@ void mem_cgroup_end_migration(struct mem_cgroup *mem, cgroup_release_and_wakeup_rmdir(&mem->css); } -/* - * A call to try to shrink memory usage on charge failure at shmem's swapin. - * Calling hierarchical_reclaim is not enough because we should update - * last_oom_jiffies to prevent pagefault_out_of_memory from invoking global OOM. - * Moreover considering hierarchy, we should reclaim from the mem_over_limit, - * not from the memcg which this page would be charged to. - * try_charge_swapin does all of these works properly. - */ -int mem_cgroup_shmem_charge_fallback(struct page *page, - struct mm_struct *mm, - gfp_t gfp_mask) -{ - struct mem_cgroup *mem; - int ret; - - if (mem_cgroup_disabled()) - return 0; - - ret = mem_cgroup_try_charge_swapin(mm, page, gfp_mask, &mem); - if (!ret) - mem_cgroup_cancel_charge_swapin(mem); /* it does !mem check */ - - return ret; -} - #ifdef CONFIG_DEBUG_VM static struct page_cgroup *lookup_page_cgroup_used(struct page *page) { @@ -5330,15 +5276,17 @@ static struct page *mc_handle_file_pte(struct vm_area_struct *vma, pgoff = pte_to_pgoff(ptent); /* page is moved even if it's not RSS of this task(page-faulted). */ - if (!mapping_cap_swap_backed(mapping)) { /* normal file */ - page = find_get_page(mapping, pgoff); - } else { /* shmem/tmpfs file. we should take account of swap too. */ - swp_entry_t ent; - mem_cgroup_get_shmem_target(inode, pgoff, &page, &ent); + page = find_get_page(mapping, pgoff); + +#ifdef CONFIG_SWAP + /* shmem/tmpfs may report page out on swap: account for that too. */ + if (radix_tree_exceptional_entry(page)) { + swp_entry_t swap = radix_to_swp_entry(page); if (do_swap_account) - entry->val = ent.val; + *entry = swap; + page = find_get_page(&swapper_space, swap.val); } - +#endif return page; } |