The ifdefs are not technically needed here, everything used here is
always defined.

They aren't doing much harm right now but a following patch will
complicate these functions. Switching to IS_ENABLED() makes the code a
bit less tiresome to read.

Signed-off-by: Brendan Jackman <jackmanb@google.com>
---
 mm/page_alloc.c | 30 ++++++++++++++----------------
 1 file changed, 14 insertions(+), 16 deletions(-)

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 10757410da2127b0488c99c5933422fc649f9a1d..08e0faab992fcf3c426d4783da041f930075d903 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -656,19 +656,17 @@ static void bad_page(struct page *page, const char *reason)
 
 static inline unsigned int order_to_pindex(int migratetype, int order)
 {
+	if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE)) {
+		bool movable = migratetype == MIGRATE_MOVABLE;
 
-#ifdef CONFIG_TRANSPARENT_HUGEPAGE
-	bool movable;
-	if (order > PAGE_ALLOC_COSTLY_ORDER) {
-		VM_BUG_ON(order != HPAGE_PMD_ORDER);
+		if (order > PAGE_ALLOC_COSTLY_ORDER) {
+			VM_BUG_ON(order != HPAGE_PMD_ORDER);
 
-		movable = migratetype == MIGRATE_MOVABLE;
-
-		return NR_LOWORDER_PCP_LISTS + movable;
+			return NR_LOWORDER_PCP_LISTS + movable;
+		}
+	} else {
+		VM_BUG_ON(order > PAGE_ALLOC_COSTLY_ORDER);
 	}
-#else
-	VM_BUG_ON(order > PAGE_ALLOC_COSTLY_ORDER);
-#endif
 
 	return (MIGRATE_PCPTYPES * order) + migratetype;
 }
@@ -677,12 +675,12 @@ static inline int pindex_to_order(unsigned int pindex)
 {
 	int order = pindex / MIGRATE_PCPTYPES;
 
-#ifdef CONFIG_TRANSPARENT_HUGEPAGE
-	if (pindex >= NR_LOWORDER_PCP_LISTS)
-		order = HPAGE_PMD_ORDER;
-#else
-	VM_BUG_ON(order > PAGE_ALLOC_COSTLY_ORDER);
-#endif
+	if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE)) {
+		if (pindex >= NR_LOWORDER_PCP_LISTS)
+			order = HPAGE_PMD_ORDER;
+	} else {
+		VM_BUG_ON(order > PAGE_ALLOC_COSTLY_ORDER);
+	}
 
 	return order;
 }

-- 
2.50.1