[PATCH v3 01/19] mm_types: add virtual and _last_cpupid into struct folio

From: Kefeng Wang
Date: Wed Oct 18 2023 - 10:09:13 EST


If WANT_PAGE_VIRTUAL and LAST_CPUPID_NOT_IN_PAGE_FLAGS defined,
the 'virtual' and '_last_cpupid' are in struct page, and since
_last_cpupid is used by numa balancing feature, it is better to
move it before KMSAN metadata from struct page, also add them
into struct folio to make us to access them from folio directly.

Signed-off-by: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>
---
include/linux/mm_types.h | 22 ++++++++++++++++++----
1 file changed, 18 insertions(+), 4 deletions(-)

diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index cc8bb767c003..34466be945a9 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -199,6 +199,10 @@ struct page {
not kmapped, ie. highmem) */
#endif /* WANT_PAGE_VIRTUAL */

+#ifdef LAST_CPUPID_NOT_IN_PAGE_FLAGS
+ int _last_cpupid;
+#endif
+
#ifdef CONFIG_KMSAN
/*
* KMSAN metadata for this page:
@@ -210,10 +214,6 @@ 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;

/*
@@ -272,6 +272,8 @@ typedef struct {
* @_refcount: Do not access this member directly. Use folio_ref_count()
* to find how many references there are to this folio.
* @memcg_data: Memory Control Group data.
+ * @virtual: Virtual address in the kernel direct map.
+ * @_last_cpupid: IDs of last CPU and last process that accessed the folio.
* @_entire_mapcount: Do not use directly, call folio_entire_mapcount().
* @_nr_pages_mapped: Do not use directly, call folio_mapcount().
* @_pincount: Do not use directly, call folio_maybe_dma_pinned().
@@ -317,6 +319,12 @@ struct folio {
atomic_t _refcount;
#ifdef CONFIG_MEMCG
unsigned long memcg_data;
+#endif
+#if defined(WANT_PAGE_VIRTUAL)
+ void *virtual;
+#endif
+#ifdef LAST_CPUPID_NOT_IN_PAGE_FLAGS
+ int _last_cpupid;
#endif
/* private: the union with struct page is transitional */
};
@@ -373,6 +381,12 @@ FOLIO_MATCH(_refcount, _refcount);
#ifdef CONFIG_MEMCG
FOLIO_MATCH(memcg_data, memcg_data);
#endif
+#if defined(WANT_PAGE_VIRTUAL)
+FOLIO_MATCH(virtual, virtual);
+#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