[124/192] mm/swap: make swap_address_space an inline function

Commit Message

Andrew Morton July 1, 2021, 1:53 a.m. UTC

From: Mel Gorman <[e-mail]>
Subject: mm/swap: make swap_address_space an inline function

make W=1 generates the following warning in page_mapping() for allnoconfig

  mm/util.c:700:15: warning: variable `entry' set but not used [-Wunused-but-set-variable]
     swp_entry_t entry;
                 ^~~~~

swap_address is a #define on !CONFIG_SWAP configurations.  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/[e-mail]
Signed-off-by: Mel Gorman <[e-mail]>
Reviewed-by: Yang Shi <[e-mail]>
Acked-by: Vlastimil Babka <[e-mail]>
Cc: Dan Streetman <[e-mail]>
Cc: David Hildenbrand <[e-mail]>
Cc: Michal Hocko <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
---

 include/linux/swap.h |    6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

Patch

--- a/include/linux/swap.h~mm-swap-make-swap_address_space-an-inline-function
+++ a/include/linux/swap.h
@@ -537,7 +537,11 @@  static inline void put_swap_device(struc
 {
 }
 
-#define swap_address_space(entry)		(NULL)
+static inline struct address_space *swap_address_space(swp_entry_t entry)
+{
+	return NULL;
+}
+
 #define get_nr_swap_pages()			0L
 #define total_swap_pages			0L
 #define total_swapcache_pages()			0UL