[PATCH 12/15] mm: page_alloc: Avoid pointer comparisons to NULL

From: Joe Perches
Date: Wed Mar 15 2017 - 22:04:03 EST


Use direct test instead.

Signed-off-by: Joe Perches <joe@xxxxxxxxxxx>
---
mm/page_alloc.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index f9e6387c0ad4..b6605b077053 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -931,7 +931,7 @@ static void free_pages_check_bad(struct page *page)

if (unlikely(atomic_read(&page->_mapcount) != -1))
bad_reason = "nonzero mapcount";
- if (unlikely(page->mapping != NULL))
+ if (unlikely(page->mapping))
bad_reason = "non-NULL mapping";
if (unlikely(page_ref_count(page) != 0))
bad_reason = "nonzero _refcount";
@@ -1668,7 +1668,7 @@ static void check_new_page_bad(struct page *page)

if (unlikely(atomic_read(&page->_mapcount) != -1))
bad_reason = "nonzero mapcount";
- if (unlikely(page->mapping != NULL))
+ if (unlikely(page->mapping))
bad_reason = "non-NULL mapping";
if (unlikely(page_ref_count(page) != 0))
bad_reason = "nonzero _count";
@@ -2289,7 +2289,7 @@ static int rmqueue_bulk(struct zone *zone, unsigned int order,
for (i = 0; i < count; ++i) {
struct page *page = __rmqueue(zone, order, migratetype);

- if (unlikely(page == NULL))
+ if (unlikely(!page))
break;

if (unlikely(check_pcp_refill(page)))
@@ -4951,7 +4951,7 @@ static void build_zonelists_in_node_order(pg_data_t *pgdat, int node)
struct zonelist *zonelist;

zonelist = &pgdat->node_zonelists[ZONELIST_FALLBACK];
- for (j = 0; zonelist->_zonerefs[j].zone != NULL; j++)
+ for (j = 0; zonelist->_zonerefs[j].zone; j++)
;
j = build_zonelists_node(NODE_DATA(node), zonelist, j);
zonelist->_zonerefs[j].zone = NULL;
--
2.10.0.rc2.1.g053435c