1 files changed, 23 insertions, 39 deletions

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 54eae4f19d80..311fd2b71bae 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -647,7 +647,7 @@ static unsigned long mem_cgroup_read_events(struct mem_cgroup *memcg,
 
 static void mem_cgroup_charge_statistics(struct mem_cgroup *memcg,
 					 struct page *page,
-					 int nr_pages)
+					 bool compound, int nr_pages)
 {
 	/*
 	 * Here, RSS means 'mapped anon' and anon's SwapCache. Shmem/tmpfs is
@@ -660,9 +660,11 @@ static void mem_cgroup_charge_statistics(struct mem_cgroup *memcg,
 		__this_cpu_add(memcg->stat->count[MEM_CGROUP_STAT_CACHE],
 				nr_pages);
 
-	if (PageTransHuge(page))
+	if (compound) {
+		VM_BUG_ON_PAGE(!PageTransHuge(page), page);
 		__this_cpu_add(memcg->stat->count[MEM_CGROUP_STAT_RSS_HUGE],
 				nr_pages);
+	}
 
 	/* pagein of a big page is an event. So, ignore page size */
 	if (nr_pages > 0)
@@ -4513,30 +4515,24 @@ static struct page *mc_handle_file_pte(struct vm_area_struct *vma,
  * from old cgroup.
  */
 static int mem_cgroup_move_account(struct page *page,
-				   unsigned int nr_pages,
+				   bool compound,
 				   struct mem_cgroup *from,
 				   struct mem_cgroup *to)
 {
 	unsigned long flags;
+	unsigned int nr_pages = compound ? hpage_nr_pages(page) : 1;
 	int ret;
 	bool anon;
 
 	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;
+	VM_BUG_ON(compound && !PageTransHuge(page));
 
 	/*
 	 * Prevent mem_cgroup_replace_page() from looking at
 	 * page->mem_cgroup of its source page while we change it.
 	 */
+	ret = -EBUSY;
 	if (!trylock_page(page))
 		goto out;
 
@@ -4591,9 +4587,9 @@ static int mem_cgroup_move_account(struct page *page,
 	ret = 0;
 
 	local_irq_disable();
-	mem_cgroup_charge_statistics(to, page, nr_pages);
+	mem_cgroup_charge_statistics(to, page, compound, nr_pages);
 	memcg_check_events(to, page);
-	mem_cgroup_charge_statistics(from, page, -nr_pages);
+	mem_cgroup_charge_statistics(from, page, compound, -nr_pages);
 	memcg_check_events(from, page);
 	local_irq_enable();
 out_unlock:
@@ -4890,7 +4886,7 @@ static int mem_cgroup_move_charge_pte_range(pmd_t *pmd,
 		if (target_type == MC_TARGET_PAGE) {
 			page = target.page;
 			if (!isolate_lru_page(page)) {
-				if (!mem_cgroup_move_account(page, HPAGE_PMD_NR,
+				if (!mem_cgroup_move_account(page, true,
 							     mc.from, mc.to)) {
 					mc.precharge -= HPAGE_PMD_NR;
 					mc.moved_charge += HPAGE_PMD_NR;
@@ -4919,7 +4915,8 @@ retry:
 			page = target.page;
 			if (isolate_lru_page(page))
 				goto put;
-			if (!mem_cgroup_move_account(page, 1, mc.from, mc.to)) {
+			if (!mem_cgroup_move_account(page, false,
+						mc.from, mc.to)) {
 				mc.precharge--;
 				/* we uncharge from mc.from later. */
 				mc.moved_charge++;
@@ -5258,10 +5255,11 @@ bool mem_cgroup_low(struct mem_cgroup *root, struct mem_cgroup *memcg)
  * with mem_cgroup_cancel_charge() in case page instantiation fails.
  */
 int mem_cgroup_try_charge(struct page *page, struct mm_struct *mm,
-			  gfp_t gfp_mask, struct mem_cgroup **memcgp)
+			  gfp_t gfp_mask, struct mem_cgroup **memcgp,
+			  bool compound)
 {
 	struct mem_cgroup *memcg = NULL;
-	unsigned int nr_pages = 1;
+	unsigned int nr_pages = compound ? hpage_nr_pages(page) : 1;
 	int ret = 0;
 
 	if (mem_cgroup_disabled())
@@ -5291,11 +5289,6 @@ int mem_cgroup_try_charge(struct page *page, struct mm_struct *mm,
 		}
 	}
 
-	if (PageTransHuge(page)) {
-		nr_pages <<= compound_order(page);
-		VM_BUG_ON_PAGE(!PageTransHuge(page), page);
-	}
-
 	if (!memcg)
 		memcg = get_mem_cgroup_from_mm(mm);
 
@@ -5324,9 +5317,9 @@ out:
  * Use mem_cgroup_cancel_charge() to cancel the transaction instead.
  */
 void mem_cgroup_commit_charge(struct page *page, struct mem_cgroup *memcg,
-			      bool lrucare)
+			      bool lrucare, bool compound)
 {
-	unsigned int nr_pages = 1;
+	unsigned int nr_pages = compound ? hpage_nr_pages(page) : 1;
 
 	VM_BUG_ON_PAGE(!page->mapping, page);
 	VM_BUG_ON_PAGE(PageLRU(page) && !lrucare, page);
@@ -5343,13 +5336,8 @@ void mem_cgroup_commit_charge(struct page *page, struct mem_cgroup *memcg,
 
 	commit_charge(page, memcg, lrucare);
 
-	if (PageTransHuge(page)) {
-		nr_pages <<= compound_order(page);
-		VM_BUG_ON_PAGE(!PageTransHuge(page), page);
-	}
-
 	local_irq_disable();
-	mem_cgroup_charge_statistics(memcg, page, nr_pages);
+	mem_cgroup_charge_statistics(memcg, page, compound, nr_pages);
 	memcg_check_events(memcg, page);
 	local_irq_enable();
 
@@ -5371,9 +5359,10 @@ void mem_cgroup_commit_charge(struct page *page, struct mem_cgroup *memcg,
  *
  * Cancel a charge transaction started by mem_cgroup_try_charge().
  */
-void mem_cgroup_cancel_charge(struct page *page, struct mem_cgroup *memcg)
+void mem_cgroup_cancel_charge(struct page *page, struct mem_cgroup *memcg,
+		bool compound)
 {
-	unsigned int nr_pages = 1;
+	unsigned int nr_pages = compound ? hpage_nr_pages(page) : 1;
 
 	if (mem_cgroup_disabled())
 		return;
@@ -5385,11 +5374,6 @@ void mem_cgroup_cancel_charge(struct page *page, struct mem_cgroup *memcg)
 	if (!memcg)
 		return;
 
-	if (PageTransHuge(page)) {
-		nr_pages <<= compound_order(page);
-		VM_BUG_ON_PAGE(!PageTransHuge(page), page);
-	}
-
 	cancel_charge(memcg, nr_pages);
 }
 
@@ -5750,7 +5734,7 @@ void mem_cgroup_swapout(struct page *page, swp_entry_t entry)
 	 * only synchronisation we have for udpating the per-CPU variables.
 	 */
 	VM_BUG_ON(!irqs_disabled());
-	mem_cgroup_charge_statistics(memcg, page, -1);
+	mem_cgroup_charge_statistics(memcg, page, false, -1);
 	memcg_check_events(memcg, page);
 }