1 files changed, 101 insertions, 93 deletions

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index b34ef4a32a3b..c3f09b2dda5f 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -14,6 +14,12 @@
  * Copyright (C) 2012 Parallels Inc. and Google Inc.
  * Authors: Glauber Costa and Suleiman Souhlal
  *
+ * Native page reclaim
+ * Charge lifetime sanitation
+ * Lockless page tracking & accounting
+ * Unified hierarchy configuration model
+ * Copyright (C) 2015 Red Hat, Inc., Johannes Weiner
+ *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; either version 2 of the License, or
@@ -1436,15 +1442,17 @@ void mem_cgroup_print_oom_info(struct mem_cgroup *memcg, struct task_struct *p)
         struct mem_cgroup *iter;
         unsigned int i;
 
-        if (!p)
-                return;
-
         mutex_lock(&oom_info_lock);
         rcu_read_lock();
 
-        pr_info("Task in ");
-        pr_cont_cgroup_path(task_cgroup(p, memory_cgrp_id));
-        pr_cont(" killed as a result of limit of ");
+        if (p) {
+                pr_info("Task in ");
+                pr_cont_cgroup_path(task_cgroup(p, memory_cgrp_id));
+                pr_cont(" killed as a result of limit of ");
+        } else {
+                pr_info("Memory limit reached of cgroup ");
+        }
+
         pr_cont_cgroup_path(memcg->css.cgroup);
         pr_cont("\n");
 
@@ -1531,7 +1539,7 @@ static void mem_cgroup_out_of_memory(struct mem_cgroup *memcg, gfp_t gfp_mask,
                 return;
         }
 
-        check_panic_on_oom(CONSTRAINT_MEMCG, gfp_mask, order, NULL);
+        check_panic_on_oom(CONSTRAINT_MEMCG, gfp_mask, order, NULL, memcg);
         totalpages = mem_cgroup_get_limit(memcg) ? : 1;
         for_each_mem_cgroup_tree(iter, memcg) {
                 struct css_task_iter it;
@@ -2779,92 +2787,6 @@ void mem_cgroup_split_huge_fixup(struct page *head)
 }
 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 
-/**
- * mem_cgroup_move_account - move account of the page
- * @page: the page
- * @nr_pages: number of regular pages (>1 for huge pages)
- * @from: mem_cgroup which the page is moved from.
- * @to: mem_cgroup which the page is moved to. @from != @to.
- *
- * The caller must confirm following.
- * - page is not on LRU (isolate_page() is useful.)
- * - compound_lock is held when nr_pages > 1
- *
- * This function doesn't do "charge" to new cgroup and doesn't do "uncharge"
- * from old cgroup.
- */
-static int mem_cgroup_move_account(struct page *page,
-                                   unsigned int nr_pages,
-                                   struct mem_cgroup *from,
-                                   struct mem_cgroup *to)
-{
-        unsigned long flags;
-        int ret;
-
-        VM_BUG_ON(from == to);
-        VM_BUG_ON_PAGE(PageLRU(page), page);
-        /*
-         * 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.
-         */
-        ret = -EBUSY;
-        if (nr_pages > 1 && !PageTransHuge(page))
-                goto out;
-
-        /*
-         * Prevent mem_cgroup_migrate() from looking at page->mem_cgroup
-         * of its source page while we change it: page migration takes
-         * both pages off the LRU, but page cache replacement doesn't.
-         */
-        if (!trylock_page(page))
-                goto out;
-
-        ret = -EINVAL;
-        if (page->mem_cgroup != from)
-                goto out_unlock;
-
-        spin_lock_irqsave(&from->move_lock, flags);
-
-        if (!PageAnon(page) && page_mapped(page)) {
-                __this_cpu_sub(from->stat->count[MEM_CGROUP_STAT_FILE_MAPPED],
-                               nr_pages);
-                __this_cpu_add(to->stat->count[MEM_CGROUP_STAT_FILE_MAPPED],
-                               nr_pages);
-        }
-
-        if (PageWriteback(page)) {
-                __this_cpu_sub(from->stat->count[MEM_CGROUP_STAT_WRITEBACK],
-                               nr_pages);
-                __this_cpu_add(to->stat->count[MEM_CGROUP_STAT_WRITEBACK],
-                               nr_pages);
-        }
-
-        /*
-         * It is safe to change page->mem_cgroup here because the page
-         * is referenced, charged, and isolated - we can't race with
-         * uncharging, charging, migration, or LRU putback.
-         */
-
-        /* caller should have done css_get */
-        page->mem_cgroup = to;
-        spin_unlock_irqrestore(&from->move_lock, flags);
-
-        ret = 0;
-
-        local_irq_disable();
-        mem_cgroup_charge_statistics(to, page, nr_pages);
-        memcg_check_events(to, page);
-        mem_cgroup_charge_statistics(from, page, -nr_pages);
-        memcg_check_events(from, page);
-        local_irq_enable();
-out_unlock:
-        unlock_page(page);
-out:
-        return ret;
-}
-
 #ifdef CONFIG_MEMCG_SWAP
 static void mem_cgroup_swap_statistics(struct mem_cgroup *memcg,
                                          bool charge)
@@ -4816,6 +4738,92 @@ static struct page *mc_handle_file_pte(struct vm_area_struct *vma,
         return page;
 }
 
+/**
+ * mem_cgroup_move_account - move account of the page
+ * @page: the page
+ * @nr_pages: number of regular pages (>1 for huge pages)
+ * @from: mem_cgroup which the page is moved from.
+ * @to: mem_cgroup which the page is moved to. @from != @to.
+ *
+ * The caller must confirm following.
+ * - page is not on LRU (isolate_page() is useful.)
+ * - compound_lock is held when nr_pages > 1
+ *
+ * This function doesn't do "charge" to new cgroup and doesn't do "uncharge"
+ * from old cgroup.
+ */
+static int mem_cgroup_move_account(struct page *page,
+                                   unsigned int nr_pages,
+                                   struct mem_cgroup *from,
+                                   struct mem_cgroup *to)
+{
+        unsigned long flags;
+        int ret;
+
+        VM_BUG_ON(from == to);
+        VM_BUG_ON_PAGE(PageLRU(page), page);
+        /*
+         * 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.
+         */
+        ret = -EBUSY;
+        if (nr_pages > 1 && !PageTransHuge(page))
+                goto out;
+
+        /*
+         * Prevent mem_cgroup_migrate() from looking at page->mem_cgroup
+         * of its source page while we change it: page migration takes
+         * both pages off the LRU, but page cache replacement doesn't.
+         */
+        if (!trylock_page(page))
+                goto out;
+
+        ret = -EINVAL;
+        if (page->mem_cgroup != from)
+                goto out_unlock;
+
+        spin_lock_irqsave(&from->move_lock, flags);
+
+        if (!PageAnon(page) && page_mapped(page)) {
+                __this_cpu_sub(from->stat->count[MEM_CGROUP_STAT_FILE_MAPPED],
+                               nr_pages);
+                __this_cpu_add(to->stat->count[MEM_CGROUP_STAT_FILE_MAPPED],
+                               nr_pages);
+        }
+
+        if (PageWriteback(page)) {
+                __this_cpu_sub(from->stat->count[MEM_CGROUP_STAT_WRITEBACK],
+                               nr_pages);
+                __this_cpu_add(to->stat->count[MEM_CGROUP_STAT_WRITEBACK],
+                               nr_pages);
+        }
+
+        /*
+         * It is safe to change page->mem_cgroup here because the page
+         * is referenced, charged, and isolated - we can't race with
+         * uncharging, charging, migration, or LRU putback.
+         */
+
+        /* caller should have done css_get */
+        page->mem_cgroup = to;
+        spin_unlock_irqrestore(&from->move_lock, flags);
+
+        ret = 0;
+
+        local_irq_disable();
+        mem_cgroup_charge_statistics(to, page, nr_pages);
+        memcg_check_events(to, page);
+        mem_cgroup_charge_statistics(from, page, -nr_pages);
+        memcg_check_events(from, page);
+        local_irq_enable();
+out_unlock:
+        unlock_page(page);
+out:
+        return ret;
+}
+
 static enum mc_target_type get_mctgt_type(struct vm_area_struct *vma,
                 unsigned long addr, pte_t ptent, union mc_target *target)
 {