[PATCH v10 07/13] mm: Kill is_dev_zone() helper

[Dan Williams <dan.j.williams@intel.com>]

Given there are no more usages of is_dev_zone() outside of 'ifdef
CONFIG_ZONE_DEVICE' protection, kill off the compilation helper.

Cc: Michal Hocko <mhocko@suse.com>
Cc: Logan Gunthorpe <logang@deltatee.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: Wei Yang <richardw.yang@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 include/linux/mmzone.h |   12 ------------
 mm/page_alloc.c        |    2 +-
 2 files changed, 1 insertion(+), 13 deletions(-)

diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index c4e8843e283c..e976faf57292 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -855,18 +855,6 @@ static inline int local_memory_node(int node_id) { return node_id; };
  */
 #define zone_idx(zone)		((zone) - (zone)->zone_pgdat->node_zones)
 
-#ifdef CONFIG_ZONE_DEVICE
-static inline bool is_dev_zone(const struct zone *zone)
-{
-	return zone_idx(zone) == ZONE_DEVICE;
-}
-#else
-static inline bool is_dev_zone(const struct zone *zone)
-{
-	return false;
-}
-#endif
-
 /*
  * Returns true if a zone has pages managed by the buddy allocator.
  * All the reclaim decisions have to use this function rather than
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 8e7215fb6976..12b2afd3a529 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -5881,7 +5881,7 @@ void __ref memmap_init_zone_device(struct zone *zone,
 	unsigned long start = jiffies;
 	int nid = pgdat->node_id;
 
-	if (WARN_ON_ONCE(!pgmap || !is_dev_zone(zone)))
+	if (WARN_ON_ONCE(!pgmap || zone_idx(zone) != ZONE_DEVICE))
 		return;
 
 	/*