include/linux/migrate.h: remove migrate_page #define

This is designed to avoid a few ifdefs in .c files but it's obnoxious because it can cause unsuspecting "migrate_page" symbols to get turned into "NULL". Just nuke it and use the ifdefs. Cc: Konstantin Khlebnikov <[email protected]> Cc: Rafael Aquini <[email protected]> Cc: Andrey Ryabinin <[email protected]> Cc: Mel Gorman <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
xingkongcwb · Oct 10, 2014 · 1c93923 · 1c93923
1 parent dd6eecb
commit 1c93923
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Showing 3 changed files with 4 additions and 3 deletions.
diff --git a/include/linux/migrate.h b/include/linux/migrate.h
@@ -82,9 +82,6 @@ static inline int migrate_huge_page_move_mapping(struct address_space *mapping,
 	return -ENOSYS;
 }
 
-/* Possible settings for the migrate_page() method in address_operations */
-#define migrate_page NULL
-
 #endif /* CONFIG_MIGRATION */
 
 #ifdef CONFIG_NUMA_BALANCING

diff --git a/mm/shmem.c b/mm/shmem.c
@@ -3077,7 +3077,9 @@ static const struct address_space_operations shmem_aops = {
 	.write_begin	= shmem_write_begin,
 	.write_end	= shmem_write_end,
 #endif
+#ifdef CONFIG_MIGRATION
 	.migratepage	= migrate_page,
+#endif
 	.error_remove_page = generic_error_remove_page,
 };
 

diff --git a/mm/swap_state.c b/mm/swap_state.c
@@ -28,7 +28,9 @@
 static const struct address_space_operations swap_aops = {
 	.writepage	= swap_writepage,
 	.set_page_dirty	= swap_set_page_dirty,
+#ifdef CONFIG_MIGRATION
 	.migratepage	= migrate_page,
+#endif
 };
 
 static struct backing_dev_info swap_backing_dev_info = {