1 files changed, 52 insertions, 0 deletions

diff --git a/mm/slab.h b/mm/slab.h
index 161ca34acb01..9f78e3167f19 100644
--- a/mm/slab.h
+++ b/mm/slab.h
@@ -109,6 +109,7 @@ struct memcg_cache_params {
 #include <linux/kmemleak.h>
 #include <linux/random.h>
 #include <linux/sched/mm.h>
+#include <linux/kmemleak.h>
 
 /*
  * State of the slab allocator.
@@ -348,6 +349,18 @@ static inline struct kmem_cache *memcg_root_cache(struct kmem_cache *s)
 	return s->memcg_params.root_cache;
 }
 
+static inline struct obj_cgroup **page_obj_cgroups(struct page *page)
+{
+	/*
+	 * page->mem_cgroup and page->obj_cgroups are sharing the same
+	 * space. To distinguish between them in case we don't know for sure
+	 * that the page is a slab page (e.g. page_cgroup_ino()), let's
+	 * always set the lowest bit of obj_cgroups.
+	 */
+	return (struct obj_cgroup **)
+		((unsigned long)page->obj_cgroups & ~0x1UL);
+}
+
 /*
  * Expects a pointer to a slab page. Please note, that PageSlab() check
  * isn't sufficient, as it returns true also for tail compound slab pages,
@@ -435,6 +448,28 @@ static __always_inline void memcg_uncharge_slab(struct page *page, int order,
 	percpu_ref_put_many(&s->memcg_params.refcnt, nr_pages);
 }
 
+static inline int memcg_alloc_page_obj_cgroups(struct page *page,
+					       struct kmem_cache *s, gfp_t gfp)
+{
+	unsigned int objects = objs_per_slab_page(s, page);
+	void *vec;
+
+	vec = kcalloc_node(objects, sizeof(struct obj_cgroup *), gfp,
+			   page_to_nid(page));
+	if (!vec)
+		return -ENOMEM;
+
+	kmemleak_not_leak(vec);
+	page->obj_cgroups = (struct obj_cgroup **) ((unsigned long)vec | 0x1UL);
+	return 0;
+}
+
+static inline void memcg_free_page_obj_cgroups(struct page *page)
+{
+	kfree(page_obj_cgroups(page));
+	page->obj_cgroups = NULL;
+}
+
 extern void slab_init_memcg_params(struct kmem_cache *);
 extern void memcg_link_cache(struct kmem_cache *s, struct mem_cgroup *memcg);
 
@@ -484,6 +519,16 @@ static inline void memcg_uncharge_slab(struct page *page, int order,
 {
 }
 
+static inline int memcg_alloc_page_obj_cgroups(struct page *page,
+					       struct kmem_cache *s, gfp_t gfp)
+{
+	return 0;
+}
+
+static inline void memcg_free_page_obj_cgroups(struct page *page)
+{
+}
+
 static inline void slab_init_memcg_params(struct kmem_cache *s)
 {
 }
@@ -510,12 +555,18 @@ static __always_inline int charge_slab_page(struct page *page,
 					    gfp_t gfp, int order,
 					    struct kmem_cache *s)
 {
+	int ret;
+
 	if (is_root_cache(s)) {
 		mod_node_page_state(page_pgdat(page), cache_vmstat_idx(s),
 				    PAGE_SIZE << order);
 		return 0;
 	}
 
+	ret = memcg_alloc_page_obj_cgroups(page, s, gfp);
+	if (ret)
+		return ret;
+
 	return memcg_charge_slab(page, gfp, order, s);
 }
 
@@ -528,6 +579,7 @@ static __always_inline void uncharge_slab_page(struct page *page, int order,
 		return;
 	}
 
+	memcg_free_page_obj_cgroups(page);
 	memcg_uncharge_slab(page, order, s);
 }