memcg: rename high level charging functions

mem_cgroup_newpage_charge is used only for charging anonymous memory so
it is better to rename it to mem_cgroup_charge_anon.

mem_cgroup_cache_charge is used for file backed memory so rename it to
mem_cgroup_charge_file.

Signed-off-by: Michal Hocko <[e-mail]>
Cc: Johannes Weiner <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

Documentation/cgroups/memcg_test.txt

···
 
    a page/swp_entry may be charged (usage += PAGE_SIZE) at
 
-	mem_cgroup_newpage_charge()
+	mem_cgroup_charge_anon()
 	  Called at new page fault and Copy-On-Write.
 
 	mem_cgroup_try_charge_swapin()
···
 	  Followed by charge-commit-cancel protocol. (With swap accounting)
 	  At commit, a charge recorded in swap_cgroup is removed.
 
-	mem_cgroup_cache_charge()
+	mem_cgroup_charge_file()
 	  Called at add_to_page_cache()
 
 	mem_cgroup_cache_charge_swapin()

include/linux/memcontrol.h

···
  * (Of course, if memcg does memory allocation in future, GFP_KERNEL is sane.)
  */
 
-extern int mem_cgroup_newpage_charge(struct page *page, struct mm_struct *mm,
+extern int mem_cgroup_charge_anon(struct page *page, struct mm_struct *mm,
 				gfp_t gfp_mask);
 /* for swap handling */
 extern int mem_cgroup_try_charge_swapin(struct mm_struct *mm,
···
 					struct mem_cgroup *memcg);
 extern void mem_cgroup_cancel_charge_swapin(struct mem_cgroup *memcg);
 
-extern int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm,
+extern int mem_cgroup_charge_file(struct page *page, struct mm_struct *mm,
 					gfp_t gfp_mask);
 
 struct lruvec *mem_cgroup_zone_lruvec(struct zone *, struct mem_cgroup *);
···
 #else /* CONFIG_MEMCG */
 struct mem_cgroup;
 
-static inline int mem_cgroup_newpage_charge(struct page *page,
+static inline int mem_cgroup_charge_anon(struct page *page,
 					struct mm_struct *mm, gfp_t gfp_mask)
 {
 	return 0;
 }
 
-static inline int mem_cgroup_cache_charge(struct page *page,
+static inline int mem_cgroup_charge_file(struct page *page,
 					struct mm_struct *mm, gfp_t gfp_mask)
 {
 	return 0;

mm/filemap.c

···
 	VM_BUG_ON_PAGE(!PageLocked(page), page);
 	VM_BUG_ON_PAGE(PageSwapBacked(page), page);
 
-	error = mem_cgroup_cache_charge(page, current->mm,
+	error = mem_cgroup_charge_file(page, current->mm,
 					gfp_mask & GFP_RECLAIM_MASK);
 	if (error)
 		return error;

mm/huge_memory.c

···
 		count_vm_event(THP_FAULT_FALLBACK);
 		return VM_FAULT_FALLBACK;
 	}
-	if (unlikely(mem_cgroup_newpage_charge(page, mm, GFP_KERNEL))) {
+	if (unlikely(mem_cgroup_charge_anon(page, mm, GFP_KERNEL))) {
 		put_page(page);
 		count_vm_event(THP_FAULT_FALLBACK);
 		return VM_FAULT_FALLBACK;
···
 					       __GFP_OTHER_NODE,
 					       vma, address, page_to_nid(page));
 		if (unlikely(!pages[i] ||
-			     mem_cgroup_newpage_charge(pages[i], mm,
+			     mem_cgroup_charge_anon(pages[i], mm,
 						       GFP_KERNEL))) {
 			if (pages[i])
 				put_page(pages[i]);
···
 		goto out;
 	}
 
-	if (unlikely(mem_cgroup_newpage_charge(new_page, mm, GFP_KERNEL))) {
+	if (unlikely(mem_cgroup_charge_anon(new_page, mm, GFP_KERNEL))) {
 		put_page(new_page);
 		if (page) {
 			split_huge_page(page);
···
 	if (!new_page)
 		return;
 
-	if (unlikely(mem_cgroup_newpage_charge(new_page, mm, GFP_KERNEL)))
+	if (unlikely(mem_cgroup_charge_anon(new_page, mm, GFP_KERNEL)))
 		return;
 
 	/*

mm/memcontrol.c

···
 	return ret;
 }
 
-int mem_cgroup_newpage_charge(struct page *page,
+int mem_cgroup_charge_anon(struct page *page,
 			      struct mm_struct *mm, gfp_t gfp_mask)
 {
 	unsigned int nr_pages = 1;
···
 					  MEM_CGROUP_CHARGE_TYPE_ANON);
 }
 
-int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm,
+int mem_cgroup_charge_file(struct page *page, struct mm_struct *mm,
 				gfp_t gfp_mask)
 {
 	enum charge_type type = MEM_CGROUP_CHARGE_TYPE_CACHE;

mm/memory.c

···
 	}
 	__SetPageUptodate(new_page);
 
-	if (mem_cgroup_newpage_charge(new_page, mm, GFP_KERNEL))
+	if (mem_cgroup_charge_anon(new_page, mm, GFP_KERNEL))
 		goto oom_free_new;
 
 	mmun_start  = address & PAGE_MASK;
···
 	 */
 	__SetPageUptodate(page);
 
-	if (mem_cgroup_newpage_charge(page, mm, GFP_KERNEL))
+	if (mem_cgroup_charge_anon(page, mm, GFP_KERNEL))
 		goto oom_free_page;
 
 	entry = mk_pte(page, vma->vm_page_prot);
···
 	if (!new_page)
 		return VM_FAULT_OOM;
 
-	if (mem_cgroup_newpage_charge(new_page, mm, GFP_KERNEL)) {
+	if (mem_cgroup_charge_anon(new_page, mm, GFP_KERNEL)) {
 		page_cache_release(new_page);
 		return VM_FAULT_OOM;
 	}

mm/shmem.c

···
 	 * the shmem_swaplist_mutex which might hold up shmem_writepage().
 	 * Charged back to the user (not to caller) when swap account is used.
 	 */
-	error = mem_cgroup_cache_charge(page, current->mm, GFP_KERNEL);
+	error = mem_cgroup_charge_file(page, current->mm, GFP_KERNEL);
 	if (error)
 		goto out;
 	/* No radix_tree_preload: swap entry keeps a place for page in tree */
···
 				goto failed;
 		}
 
-		error = mem_cgroup_cache_charge(page, current->mm,
+		error = mem_cgroup_charge_file(page, current->mm,
 						gfp & GFP_RECLAIM_MASK);
 		if (!error) {
 			error = shmem_add_to_page_cache(page, mapping, index,
···
 
 		SetPageSwapBacked(page);
 		__set_page_locked(page);
-		error = mem_cgroup_cache_charge(page, current->mm,
+		error = mem_cgroup_charge_file(page, current->mm,
 						gfp & GFP_RECLAIM_MASK);
 		if (error)
 			goto decused;