hugetlb: convert PageHugeFreed to HPageFreed flag

Use new hugetlb specific HPageFreed flag to replace the PageHugeFreed
interfaces.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Mike Kravetz <[email protected]>
Reviewed-by: Oscar Salvador <[email protected]>
Reviewed-by: Muchun Song <[email protected]>
Acked-by: Michal Hocko <[email protected]>
Cc: David Hildenbrand <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Miaohe Lin <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Naoya Horiguchi <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

include/linux/hugetlb.h

@@ -487,11 +487,13 @@ unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
  *	allocator.  Typically used for migration target pages when no pages
  *	are available in the pool.  The hugetlb free page path will
  *	immediately free pages with this flag set to the buddy allocator.
+ * HPG_freed - Set when page is on the free lists.
  */
 enum hugetlb_page_flags {
 	HPG_restore_reserve = 0,
 	HPG_migratable,
 	HPG_temporary,
+	HPG_freed,
 	__NR_HPAGEFLAGS,
 };
 
@@ -536,6 +538,7 @@ static inline void ClearHPage##uname(struct page *page)		\
 HPAGEFLAG(RestoreReserve, restore_reserve)
 HPAGEFLAG(Migratable, migratable)
 HPAGEFLAG(Temporary, temporary)
+HPAGEFLAG(Freed, freed)
 
 #ifdef CONFIG_HUGETLB_PAGE
 

mm/hugetlb.c

@@ -79,21 +79,6 @@ DEFINE_SPINLOCK(hugetlb_lock);
 static int num_fault_mutexes;
 struct mutex *hugetlb_fault_mutex_table ____cacheline_aligned_in_smp;
 
-static inline bool PageHugeFreed(struct page *head)
-{
-	return page_private(head + 4) == -1UL;
-}
-
-static inline void SetPageHugeFreed(struct page *head)
-{
-	set_page_private(head + 4, -1UL);
-}
-
-static inline void ClearPageHugeFreed(struct page *head)
-{
-	set_page_private(head + 4, 0);
-}
-
 /* Forward declaration */
 static int hugetlb_acct_memory(struct hstate *h, long delta);
 
@@ -1053,7 +1038,7 @@ static void enqueue_huge_page(struct hstate *h, struct page *page)
 	list_move(&page->lru, &h->hugepage_freelists[nid]);
 	h->free_huge_pages++;
 	h->free_huge_pages_node[nid]++;
-	SetPageHugeFreed(page);
+	SetHPageFreed(page);
 }
 
 static struct page *dequeue_huge_page_node_exact(struct hstate *h, int nid)
@@ -1070,7 +1055,7 @@ static struct page *dequeue_huge_page_node_exact(struct hstate *h, int nid)
 
 		list_move(&page->lru, &h->hugepage_activelist);
 		set_page_refcounted(page);
-		ClearPageHugeFreed(page);
+		ClearHPageFreed(page);
 		h->free_huge_pages--;
 		h->free_huge_pages_node[nid]--;
 		return page;
@@ -1485,7 +1470,7 @@ static void prep_new_huge_page(struct hstate *h, struct page *page, int nid)
 	spin_lock(&hugetlb_lock);
 	h->nr_huge_pages++;
 	h->nr_huge_pages_node[nid]++;
-	ClearPageHugeFreed(page);
+	ClearHPageFreed(page);
 	spin_unlock(&hugetlb_lock);
 }
 
@@ -1756,7 +1741,7 @@ int dissolve_free_huge_page(struct page *page)
 		 * We should make sure that the page is already on the free list
 		 * when it is dissolved.
 		 */
-		if (unlikely(!PageHugeFreed(head))) {
+		if (unlikely(!HPageFreed(head))) {
 			spin_unlock(&hugetlb_lock);
 			cond_resched();