2 files changed, 13 insertions, 44 deletions

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index a1c05ff5892d..e249279f60c1 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -2404,57 +2404,26 @@ void __memcg_kmem_put_cache(struct kmem_cache *cachep)
 		css_put(&cachep->memcg_params.memcg->css);
 }
 
-/*
- * We need to verify if the allocation against current->mm->owner's memcg is
- * possible for the given order. But the page is not allocated yet, so we'll
- * need a further commit step to do the final arrangements.
- *
- * It is possible for the task to switch cgroups in this mean time, so at
- * commit time, we can't rely on task conversion any longer.  We'll then use
- * the handle argument to return to the caller which cgroup we should commit
- * against. We could also return the memcg directly and avoid the pointer
- * passing, but a boolean return value gives better semantics considering
- * the compiled-out case as well.
- *
- * Returning true means the allocation is possible.
- */
-bool
-__memcg_kmem_newpage_charge(gfp_t gfp, struct mem_cgroup **_memcg, int order)
+int __memcg_kmem_charge(struct page *page, gfp_t gfp, int order)
 {
 	struct mem_cgroup *memcg;
 	int ret;
 
-	*_memcg = NULL;
-
 	memcg = get_mem_cgroup_from_mm(current->mm);
 
 	if (!memcg_kmem_is_active(memcg)) {
 		css_put(&memcg->css);
-		return true;
+		return 0;
 	}
 
 	ret = memcg_charge_kmem(memcg, gfp, 1 << order);
-	if (!ret)
-		*_memcg = memcg;
 
 	css_put(&memcg->css);
-	return (ret == 0);
-}
-
-void __memcg_kmem_commit_charge(struct page *page, struct mem_cgroup *memcg,
-			      int order)
-{
-	VM_BUG_ON(mem_cgroup_is_root(memcg));
-
-	/* The page allocation failed. Revert */
-	if (!page) {
-		memcg_uncharge_kmem(memcg, 1 << order);
-		return;
-	}
 	page->mem_cgroup = memcg;
+	return ret;
 }
 
-void __memcg_kmem_uncharge_pages(struct page *page, int order)
+void __memcg_kmem_uncharge(struct page *page, int order)
 {
 	struct mem_cgroup *memcg = page->mem_cgroup;
 
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 06e62300d627..446bb36ee59d 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -3428,24 +3428,24 @@ EXPORT_SYMBOL(__free_page_frag);
 struct page *alloc_kmem_pages(gfp_t gfp_mask, unsigned int order)
 {
 	struct page *page;
-	struct mem_cgroup *memcg = NULL;
 
-	if (!memcg_kmem_newpage_charge(gfp_mask, &memcg, order))
-		return NULL;
 	page = alloc_pages(gfp_mask, order);
-	memcg_kmem_commit_charge(page, memcg, order);
+	if (page && memcg_kmem_charge(page, gfp_mask, order) != 0) {
+		__free_pages(page, order);
+		page = NULL;
+	}
 	return page;
 }
 
 struct page *alloc_kmem_pages_node(int nid, gfp_t gfp_mask, unsigned int order)
 {
 	struct page *page;
-	struct mem_cgroup *memcg = NULL;
 
-	if (!memcg_kmem_newpage_charge(gfp_mask, &memcg, order))
-		return NULL;
 	page = alloc_pages_node(nid, gfp_mask, order);
-	memcg_kmem_commit_charge(page, memcg, order);
+	if (page && memcg_kmem_charge(page, gfp_mask, order) != 0) {
+		__free_pages(page, order);
+		page = NULL;
+	}
 	return page;
 }
 
@@ -3455,7 +3455,7 @@ struct page *alloc_kmem_pages_node(int nid, gfp_t gfp_mask, unsigned int order)
  */
 void __free_kmem_pages(struct page *page, unsigned int order)
 {
-	memcg_kmem_uncharge_pages(page, order);
+	memcg_kmem_uncharge(page, order);
 	__free_pages(page, order);
 }