[PATCH] mm: cleanup is_highmem()

[Kefeng Wang <wangkefeng.wang@huawei.com>]

It is unnecessary to add CONFIG_HIGHMEM check in is_highmem(),
which has been done in is_highmem_idx(), and move is_highmem()
close to is_highmem_idx(). This has no functional impact.

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
---
 include/linux/mmzone.h | 20 ++++++++------------
 1 file changed, 8 insertions(+), 12 deletions(-)

diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index aab70355d64f..b53c59129ada 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -1053,15 +1053,6 @@ static inline int is_highmem_idx(enum zone_type idx)
 #endif
 }
 
-#ifdef CONFIG_ZONE_DMA
-bool has_managed_dma(void);
-#else
-static inline bool has_managed_dma(void)
-{
-	return false;
-}
-#endif
-
 /**
  * is_highmem - helper function to quickly check if a struct zone is a
  *              highmem zone or not.  This is an attempt to keep references
@@ -1071,12 +1062,17 @@ static inline bool has_managed_dma(void)
  */
 static inline int is_highmem(struct zone *zone)
 {
-#ifdef CONFIG_HIGHMEM
 	return is_highmem_idx(zone_idx(zone));
+}
+
+#ifdef CONFIG_ZONE_DMA
+bool has_managed_dma(void);
 #else
-	return 0;
-#endif
+static inline bool has_managed_dma(void)
+{
+	return false;
 }
+#endif
 
 /* These two functions are used to setup the per zone pages min values */
 struct ctl_table;
-- 
2.35.3