[PATCH -next 1/9] mm_types: add _last_cpupid into folio

From: Kefeng Wang
Date: Mon Sep 25 2023 - 20:53:22 EST


At present, only arc/sparc/m68k define WANT_PAGE_VIRTUAL, both of
them don't support numa balancing, and the page struct is aligned
to _struct_page_alignment, it is safe to move _last_cpupid before
'virtual' in page, meanwhile, add it into folio, which make us to
use folio->_last_cpupid directly.

Signed-off-by: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>
---
include/linux/mm_types.h | 13 +++++++++----
1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index 5a995089cbf5..2fdfddd8264a 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -183,6 +183,9 @@ struct page {
#ifdef CONFIG_MEMCG
unsigned long memcg_data;
#endif
+#ifdef LAST_CPUPID_NOT_IN_PAGE_FLAGS
+ int _last_cpupid;
+#endif

/*
* On machines where all RAM is mapped into kernel address space,
@@ -210,10 +213,6 @@ struct page {
struct page *kmsan_shadow;
struct page *kmsan_origin;
#endif
-
-#ifdef LAST_CPUPID_NOT_IN_PAGE_FLAGS
- int _last_cpupid;
-#endif
} _struct_page_alignment;

/*
@@ -328,6 +327,9 @@ struct folio {
atomic_t _refcount;
#ifdef CONFIG_MEMCG
unsigned long memcg_data;
+#endif
+#ifdef LAST_CPUPID_NOT_IN_PAGE_FLAGS
+ int _last_cpupid;
#endif
/* private: the union with struct page is transitional */
};
@@ -384,6 +386,9 @@ FOLIO_MATCH(_refcount, _refcount);
#ifdef CONFIG_MEMCG
FOLIO_MATCH(memcg_data, memcg_data);
#endif
+#ifdef LAST_CPUPID_NOT_IN_PAGE_FLAGS
+FOLIO_MATCH(_last_cpupid, _last_cpupid);
+#endif
#undef FOLIO_MATCH
#define FOLIO_MATCH(pg, fl) \
static_assert(offsetof(struct folio, fl) == \
--
2.27.0