From: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
Subject: mm/swap: make NODE_DATA an inline function on CONFIG_FLATMEM
make W=1 generates the following warning in mm/workingset.c for allnoconfig
mm/workingset.c: In function `unpack_shadow':
mm/workingset.c:201:15: warning: variable `nid' set but not used [-Wunused-but-set-variable]
int memcgid, nid;
^~~
On FLATMEM, NODE_DATA returns a global pglist_data without dereferencing
nid. Make the helper an inline function to suppress the warning, add type
checking and to apply any side-effects in the parameter list.
Link: https://lkml.kernel.org/r/20210520084809.8576-15-mgorman@xxxxxxxxxxxxxxxxxxx
Signed-off-by: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
Reviewed-by: Yang Shi <shy828301@xxxxxxxxx>
Acked-by: Vlastimil Babka <vbabka@xxxxxxx>
Cc: Dan Streetman <ddstreet@xxxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/mmzone.h | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
--- a/include/linux/mmzone.h~mm-swap-make-node_data-an-inline-function-on-config_flatmem
+++ a/include/linux/mmzone.h
@@ -1064,7 +1064,10 @@ extern char numa_zonelist_order[];
#ifndef CONFIG_NUMA
extern struct pglist_data contig_page_data;
-#define NODE_DATA(nid) (&contig_page_data)
+static inline struct pglist_data *NODE_DATA(int nid)
+{
+ return &contig_page_data;
+}
#define NODE_MEM_MAP(nid) mem_map
#else /* CONFIG_NUMA */
_
