mm: rename page struct field helpers

The function names page_xchg_last_nid(), page_last_nid() and
reset_page_last_nid() were judged to be inconsistent so rename them to a
struct_field_op style pattern. As it looked jarring to have
reset_page_mapcount() and page_nid_reset_last() beside each other in
memmap_init_zone(), this patch also renames reset_page_mapcount() to
page_mapcount_reset(). There are others like init_page_count() but as
it is used throughout the arch code a rename would likely cause more
conflicts than it is worth.

[[e-mail]: fix zcache]
Signed-off-by: Mel Gorman <[e-mail]>
Suggested-by: Andrew Morton <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

drivers/staging/zcache/zbud.c

···
 	else
 		zbud_pers_pageframes--;
 	zbudpage_spin_unlock(zbudpage);
-	reset_page_mapcount(page);
+	page_mapcount_reset(page);
 	init_page_count(page);
 	page->index = 0;
 	return page;

drivers/staging/zsmalloc/zsmalloc-main.c

···
 	set_page_private(page, 0);
 	page->mapping = NULL;
 	page->freelist = NULL;
-	reset_page_mapcount(page);
+	page_mapcount_reset(page);
 }
 
 static void free_zspage(struct page *first_page)

include/linux/mm.h

···
  * both from it and to it can be tracked, using atomic_inc_and_test
  * and atomic_add_negative(-1).
  */
-static inline void reset_page_mapcount(struct page *page)
+static inline void page_mapcount_reset(struct page *page)
 {
 	atomic_set(&(page)->_mapcount, -1);
 }
···
 
 #ifdef CONFIG_NUMA_BALANCING
 #ifdef LAST_NID_NOT_IN_PAGE_FLAGS
-static inline int page_xchg_last_nid(struct page *page, int nid)
+static inline int page_nid_xchg_last(struct page *page, int nid)
 {
 	return xchg(&page->_last_nid, nid);
 }
 
-static inline int page_last_nid(struct page *page)
+static inline int page_nid_last(struct page *page)
 {
 	return page->_last_nid;
 }
-static inline void reset_page_last_nid(struct page *page)
+static inline void page_nid_reset_last(struct page *page)
 {
 	page->_last_nid = -1;
 }
 #else
-static inline int page_last_nid(struct page *page)
+static inline int page_nid_last(struct page *page)
 {
 	return (page->flags >> LAST_NID_PGSHIFT) & LAST_NID_MASK;
 }
 
-extern int page_xchg_last_nid(struct page *page, int nid);
+extern int page_nid_xchg_last(struct page *page, int nid);
 
-static inline void reset_page_last_nid(struct page *page)
+static inline void page_nid_reset_last(struct page *page)
 {
 	int nid = (1 << LAST_NID_SHIFT) - 1;
 
···
 }
 #endif /* LAST_NID_NOT_IN_PAGE_FLAGS */
 #else
-static inline int page_xchg_last_nid(struct page *page, int nid)
+static inline int page_nid_xchg_last(struct page *page, int nid)
 {
 	return page_to_nid(page);
 }
 
-static inline int page_last_nid(struct page *page)
+static inline int page_nid_last(struct page *page)
 {
 	return page_to_nid(page);
 }
 
-static inline void reset_page_last_nid(struct page *page)
+static inline void page_nid_reset_last(struct page *page)
 {
 }
 #endif

mm/huge_memory.c

···
 		page_tail->mapping = page->mapping;
 
 		page_tail->index = page->index + i;
-		page_xchg_last_nid(page_tail, page_last_nid(page));
+		page_nid_xchg_last(page_tail, page_nid_last(page));
 
 		BUG_ON(!PageAnon(page_tail));
 		BUG_ON(!PageUptodate(page_tail));

mm/mempolicy.c

···
 		 * it less likely we act on an unlikely task<->page
 		 * relation.
 		 */
-		last_nid = page_xchg_last_nid(page, polnid);
+		last_nid = page_nid_xchg_last(page, polnid);
 		if (last_nid != polnid)
 			goto out;
 	}

mm/migrate.c

···
 					  __GFP_NOWARN) &
 					 ~GFP_IOFS, 0);
 	if (newpage)
-		page_xchg_last_nid(newpage, page_last_nid(page));
+		page_nid_xchg_last(newpage, page_nid_last(page));
 
 	return newpage;
 }
···
 	if (!new_page)
 		goto out_fail;
 
-	page_xchg_last_nid(new_page, page_last_nid(page));
+	page_nid_xchg_last(new_page, page_nid_last(page));
 
 	isolated = numamigrate_isolate_page(pgdat, page);
 	if (!isolated) {

mm/mmzone.c

···
 }
 
 #if defined(CONFIG_NUMA_BALANCING) && !defined(LAST_NID_NOT_IN_PAGE_FLAGS)
-int page_xchg_last_nid(struct page *page, int nid)
+int page_nid_xchg_last(struct page *page, int nid)
 {
 	unsigned long old_flags, flags;
 	int last_nid;
 
 	do {
 		old_flags = flags = page->flags;
-		last_nid = page_last_nid(page);
+		last_nid = page_nid_last(page);
 
 		flags &= ~(LAST_NID_MASK << LAST_NID_PGSHIFT);
 		flags |= (nid & LAST_NID_MASK) << LAST_NID_PGSHIFT;

mm/page_alloc.c

···
 
 	/* Don't complain about poisoned pages */
 	if (PageHWPoison(page)) {
-		reset_page_mapcount(page); /* remove PageBuddy */
+		page_mapcount_reset(page); /* remove PageBuddy */
 		return;
 	}
 
···
 	dump_stack();
 out:
 	/* Leave bad fields for debug, except PageBuddy could make trouble */
-	reset_page_mapcount(page); /* remove PageBuddy */
+	page_mapcount_reset(page); /* remove PageBuddy */
 	add_taint(TAINT_BAD_PAGE);
 }
 
···
 		bad_page(page);
 		return 1;
 	}
-	reset_page_last_nid(page);
+	page_nid_reset_last(page);
 	if (page->flags & PAGE_FLAGS_CHECK_AT_PREP)
 		page->flags &= ~PAGE_FLAGS_CHECK_AT_PREP;
 	return 0;
···
 		set_page_links(page, zone, nid, pfn);
 		mminit_verify_page_links(page, zone, nid, pfn);
 		init_page_count(page);
-		reset_page_mapcount(page);
-		reset_page_last_nid(page);
+		page_mapcount_reset(page);
+		page_nid_reset_last(page);
 		SetPageReserved(page);
 		/*
 		 * Mark the block movable so that blocks are reserved for

mm/slob.c

···
 			clear_slob_page_free(sp);
 		spin_unlock_irqrestore(&slob_lock, flags);
 		__ClearPageSlab(sp);
-		reset_page_mapcount(sp);
+		page_mapcount_reset(sp);
 		slob_free_pages(b, 0);
 		return;
 	}

mm/slub.c

···
 	__ClearPageSlab(page);
 
 	memcg_release_pages(s, order);
-	reset_page_mapcount(page);
+	page_mapcount_reset(page);
 	if (current->reclaim_state)
 		current->reclaim_state->reclaimed_slab += pages;
 	__free_memcg_kmem_pages(page, order);