[RFC PATCH 3/3] hugetlb: convert PageHugeTemporary() to HPageTempSurplus

[Mike Kravetz]

Use new hugetlb specific flag HPageTempSurplus to replace the
PageHugeTemporary() interfaces.

Signed-off-by: Mike Kravetz <mike.kravetz@xxxxxxxxxx>
---
 mm/hugetlb.c | 38 +++++++++-----------------------------
 1 file changed, 9 insertions(+), 29 deletions(-)

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 34ce82f4823c..949e1f987319 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -58,6 +58,7 @@ static unsigned long hugetlb_cma_size __initdata;
 enum htlb_page_flags {
 	HPAGE_RestoreReserve = 0,
 	HPAGE_Migratable,
+	HPAGE_TempSurplus,
 };
 
 /*
@@ -99,6 +100,7 @@ void ClearHPage##flname(struct page *page)	\
 
 HPAGEFLAG(RestoreReserve)
 EXT_HPAGEFLAG(Migratable)
+HPAGEFLAG(TempSurplus)
 
 /*
  * hugetlb page subpool pointer located in hpage[1].private
@@ -1398,28 +1400,6 @@ struct hstate *size_to_hstate(unsigned long size)
 	return NULL;
 }
 
-/*
- * Internal hugetlb specific page flag. Do not use outside of the hugetlb
- * code
- */
-static inline bool PageHugeTemporary(struct page *page)
-{
-	if (!PageHuge(page))
-		return false;
-
-	return (unsigned long)page[2].mapping == -1U;
-}
-
-static inline void SetPageHugeTemporary(struct page *page)
-{
-	page[2].mapping = (void *)-1U;
-}
-
-static inline void ClearPageHugeTemporary(struct page *page)
-{
-	page[2].mapping = NULL;
-}
-
 static void __free_huge_page(struct page *page)
 {
 	/*
@@ -1467,9 +1447,9 @@ static void __free_huge_page(struct page *page)
 	if (restore_reserve)
 		h->resv_huge_pages++;
 
-	if (PageHugeTemporary(page)) {
+	if (HPageTempSurplus(page)) {
 		list_del(&page->lru);
-		ClearPageHugeTemporary(page);
+		ClearHPageTempSurplus(page);
 		update_and_free_page(h, page);
 	} else if (h->surplus_huge_pages_node[nid]) {
 		/* remove the page from active list */
@@ -1883,7 +1863,7 @@ static struct page *alloc_surplus_huge_page(struct hstate *h, gfp_t gfp_mask,
 	 * codeflow
 	 */
 	if (h->surplus_huge_pages >= h->nr_overcommit_huge_pages) {
-		SetPageHugeTemporary(page);
+		SetHPageTempSurplus(page);
 		spin_unlock(&hugetlb_lock);
 		put_page(page);
 		return NULL;
@@ -1914,7 +1894,7 @@ static struct page *alloc_migrate_huge_page(struct hstate *h, gfp_t gfp_mask,
 	 * We do not account these pages as surplus because they are only
 	 * temporary and will be released properly on the last reference
 	 */
-	SetPageHugeTemporary(page);
+	SetHPageTempSurplus(page);
 
 	return page;
 }
@@ -5612,12 +5592,12 @@ void move_hugetlb_state(struct page *oldpage, struct page *newpage, int reason)
 	 * here as well otherwise the global surplus count will not match
 	 * the per-node's.
 	 */
-	if (PageHugeTemporary(newpage)) {
+	if (HPageTempSurplus(newpage)) {
 		int old_nid = page_to_nid(oldpage);
 		int new_nid = page_to_nid(newpage);
 
-		SetPageHugeTemporary(oldpage);
-		ClearPageHugeTemporary(newpage);
+		SetHPageTempSurplus(oldpage);
+		ClearHPageTempSurplus(newpage);
 
 		spin_lock(&hugetlb_lock);
 		if (h->surplus_huge_pages_node[old_nid]) {
-- 
2.29.2