[RFC PATCH 1/3] mm: Factor out the pagetable pages account into new helper function

[Baolin Wang <baolin.wang@linux.alibaba.com>]

Factor out the pagetable pages account into new helper functions to avoid
duplicated code. Meanwhile these helper functions also will be used to
account pagetable pages which do not need split pagetale lock.

Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
---
 include/linux/mm.h | 24 ++++++++++++++++--------
 1 file changed, 16 insertions(+), 8 deletions(-)

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 8a96197..1ce3366 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2358,20 +2358,30 @@ static inline void pgtable_init(void)
 	pgtable_cache_init();
 }
 
+static inline void pgtable_set_and_inc(struct page *page)
+{
+	__SetPageTable(page);
+	inc_lruvec_page_state(page, NR_PAGETABLE);
+}
+
+static inline void pgtable_clear_and_dec(struct page *page)
+{
+	__ClearPageTable(page);
+	dec_lruvec_page_state(page, NR_PAGETABLE);
+}
+
 static inline bool pgtable_pte_page_ctor(struct page *page)
 {
 	if (!ptlock_init(page))
 		return false;
-	__SetPageTable(page);
-	inc_lruvec_page_state(page, NR_PAGETABLE);
+	pgtable_set_and_inc(page);
 	return true;
 }
 
 static inline void pgtable_pte_page_dtor(struct page *page)
 {
 	ptlock_free(page);
-	__ClearPageTable(page);
-	dec_lruvec_page_state(page, NR_PAGETABLE);
+	pgtable_clear_and_dec(page);
 }
 
 #define pte_offset_map_lock(mm, pmd, address, ptlp)	\
@@ -2457,16 +2467,14 @@ static inline bool pgtable_pmd_page_ctor(struct page *page)
 {
 	if (!pmd_ptlock_init(page))
 		return false;
-	__SetPageTable(page);
-	inc_lruvec_page_state(page, NR_PAGETABLE);
+	pgtable_set_and_inc(page);
 	return true;
 }
 
 static inline void pgtable_pmd_page_dtor(struct page *page)
 {
 	pmd_ptlock_free(page);
-	__ClearPageTable(page);
-	dec_lruvec_page_state(page, NR_PAGETABLE);
+	pgtable_clear_and_dec(page);
 }
 
 /*
-- 
1.8.3.1