Re: [PATCH 1/2] mm: use is_migrate_highatomic() to simplify the code

[Andrew Morton]

On Fri, 3 Mar 2017 14:18:08 +0100 Michal Hocko <mhocko@xxxxxxxxxx> wrote:

> On Fri 03-03-17 19:10:13, Xishi Qiu wrote:
> > Introduce two helpers, is_migrate_highatomic() and is_migrate_highatomic_page().
> > Simplify the code, no functional changes.
> 
> static inline helpers would be nicer than macros

Always.

We made a big dependency mess in mmzone.h.  internal.h works.

--- a/include/linux/mmzone.h~mm-use-is_migrate_highatomic-to-simplify-the-code-fix
+++ a/include/linux/mmzone.h
@@ -35,7 +35,7 @@
  */
 #define PAGE_ALLOC_COSTLY_ORDER 3
 
-enum {
+enum migratetype {
 	MIGRATE_UNMOVABLE,
 	MIGRATE_MOVABLE,
 	MIGRATE_RECLAIMABLE,
@@ -66,11 +66,6 @@ enum {
 /* In mm/page_alloc.c; keep in sync also with show_migration_types() there */
 extern char * const migratetype_names[MIGRATE_TYPES];
 
-#define is_migrate_highatomic(migratetype)				\
-	(migratetype == MIGRATE_HIGHATOMIC)
-#define is_migrate_highatomic_page(_page)				\
-	(get_pageblock_migratetype(_page) == MIGRATE_HIGHATOMIC)
-
 #ifdef CONFIG_CMA
 #  define is_migrate_cma(migratetype) unlikely((migratetype) == MIGRATE_CMA)
 #  define is_migrate_cma_page(_page) (get_pageblock_migratetype(_page) == MIGRATE_CMA)
diff -puN mm/page_alloc.c~mm-use-is_migrate_highatomic-to-simplify-the-code-fix mm/page_alloc.c
diff -puN mm/internal.h~mm-use-is_migrate_highatomic-to-simplify-the-code-fix mm/internal.h
--- a/mm/internal.h~mm-use-is_migrate_highatomic-to-simplify-the-code-fix
+++ a/mm/internal.h
@@ -503,4 +503,14 @@ extern const struct trace_print_flags pa
 extern const struct trace_print_flags vmaflag_names[];
 extern const struct trace_print_flags gfpflag_names[];
 
+static inline bool is_migrate_highatomic(enum migratetype migratetype)
+{
+	return migratetype == MIGRATE_HIGHATOMIC;
+}
+
+static inline bool is_migrate_highatomic_page(struct page *page)
+{
+	return get_pageblock_migratetype(page) == MIGRATE_HIGHATOMIC;
+}
+
 #endif	/* __MM_INTERNAL_H */
_