During page isolation, the original migratetype is overwritten, since
MIGRATE_* are enums. Change MIGRATE_ISOLATE to be a standalone bit like
PB_migrate_skip. pageblock bits needs to be word aligned, so expand
the number of pageblock bits from 4 to 8 and make migrate isolate bit 7.
Signed-off-by: Zi Yan <ziy@xxxxxxxxxx>
---
include/linux/mmzone.h | 24 ++++++++++++++++++++----
include/linux/page-isolation.h | 2 +-
include/linux/pageblock-flags.h | 29 ++++++++++++++++++++++++++++-
mm/page_alloc.c | 22 ++++++++++++++++++++--
4 files changed, 69 insertions(+), 8 deletions(-)
diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index 17506e4a2835..5191a90b94f9 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -108,12 +108,28 @@ extern int page_group_by_mobility_disabled;
#define MIGRATETYPE_MASK ((1UL << PB_migratetype_bits) - 1)
-#define get_pageblock_migratetype(page) \
- get_pfnblock_flags_mask(page, page_to_pfn(page), MIGRATETYPE_MASK)
+#ifdef CONFIG_MEMORY_ISOLATION
+#define get_pageblock_migratetype(page) \
+ (get_pageblock_isolate(page) ? \
+ MIGRATE_ISOLATE : \
+ get_pfnblock_flags_mask(page, page_to_pfn(page), \
+ MIGRATETYPE_MASK))
+
+#define folio_migratetype(folio) \
+ (get_pageblock_isolate(&folio->page) ? \
+ MIGRATE_ISOLATE : \
+ get_pfnblock_flags_mask(&folio->page, folio_pfn(folio), \
+ MIGRATETYPE_MASK))
+#else
+#define get_pageblock_migratetype(page) \
+ get_pfnblock_flags_mask(page, page_to_pfn(page), \
+ MIGRATETYPE_MASK)
-#define folio_migratetype(folio) \
- get_pfnblock_flags_mask(&folio->page, folio_pfn(folio), \
+#define folio_migratetype(folio) \
+ get_pfnblock_flags_mask(&folio->page, folio_pfn(folio), \
MIGRATETYPE_MASK)
+#endif
+
struct free_area {
struct list_head free_list[MIGRATE_TYPES];
unsigned long nr_free;
diff --git a/include/linux/page-isolation.h b/include/linux/page-isolation.h
index c16db0067090..11b8695115ea 100644
--- a/include/linux/page-isolation.h
+++ b/include/linux/page-isolation.h
@@ -9,7 +9,7 @@ static inline bool has_isolate_pageblock(struct zone *zone)
}
static inline bool is_migrate_isolate_page(struct page *page)
{
- return get_pageblock_migratetype(page) == MIGRATE_ISOLATE;
+ return get_pageblock_isolate(page);
}
static inline bool is_migrate_isolate(int migratetype)
{
diff --git a/include/linux/pageblock-flags.h b/include/linux/pageblock-flags.h
index fc6b9c87cb0a..a8121cab4b4f 100644
--- a/include/linux/pageblock-flags.h
+++ b/include/linux/pageblock-flags.h
@@ -20,7 +20,10 @@ enum pageblock_bits {
PB_migrate_end = PB_migrate + PB_migratetype_bits - 1,
/* 3 bits required for migrate types */
PB_migrate_skip,/* If set the block is skipped by compaction */
-
+#ifdef CONFIG_MEMORY_ISOLATION
+ PB_migrate_isolate = 7, /* If set the block is isolated */
+ /* set it to 7 to make pageblock bit word aligned */
+#endif
/*
* Assume the bits will always align on a word. If this assumption
* changes then get/set pageblock needs updating.
@@ -99,4 +102,28 @@ static inline void set_pageblock_skip(struct page *page)
}
#endif /* CONFIG_COMPACTION */
+#ifdef CONFIG_MEMORY_ISOLATION
+#define get_pageblock_isolate(page) \
+ get_pfnblock_flags_mask(page, page_to_pfn(page), \
+ (1 << (PB_migrate_isolate)))
+#define clear_pageblock_isolate(page) \
+ set_pfnblock_flags_mask(page, 0, page_to_pfn(page), \
+ (1 << PB_migrate_isolate))
+#define set_pageblock_isolate(page) \
+ set_pfnblock_flags_mask(page, (1 << PB_migrate_isolate), \
+ page_to_pfn(page), \
+ (1 << PB_migrate_isolate))
+#else
+static inline bool get_pageblock_isolate(struct page *page)
+{
+ return false;
+}
+static inline void clear_pageblock_isolate(struct page *page)
+{
+}
+static inline void set_pageblock_isolate(struct page *page)
+{
+}
+#endif /* CONFIG_MEMORY_ISOLATION */
+
#endif /* PAGEBLOCK_FLAGS_H */
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index c2ffccf9d213..4ea5cd1a07e2 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -380,7 +380,12 @@ unsigned long get_pfnblock_flags_mask(const struct page *page,
static __always_inline int get_pfnblock_migratetype(const struct page *page,
unsigned long pfn)
{
- return get_pfnblock_flags_mask(page, pfn, MIGRATETYPE_MASK);
+ return
+#ifdef CONFIG_MEMORY_ISOLATION
+ get_pageblock_isolate(page) ?
+ MIGRATE_ISOLATE :
+#endif
+ get_pfnblock_flags_mask(page, pfn, MIGRATETYPE_MASK);
}
/**
@@ -398,7 +403,11 @@ void set_pfnblock_flags_mask(struct page *page, unsigned long flags,
unsigned long bitidx, word_bitidx;
unsigned long word;
+#ifdef CONFIG_MEMORY_ISOLATION
+ BUILD_BUG_ON(NR_PAGEBLOCK_BITS != 8);
+#else
BUILD_BUG_ON(NR_PAGEBLOCK_BITS != 4);
+#endif
BUILD_BUG_ON(MIGRATE_TYPES > (1 << PB_migratetype_bits));
bitmap = get_pageblock_bitmap(page, pfn);
@@ -422,8 +431,17 @@ void set_pageblock_migratetype(struct page *page, int migratetype)
migratetype < MIGRATE_PCPTYPES))
migratetype = MIGRATE_UNMOVABLE;
- set_pfnblock_flags_mask(page, (unsigned long)migratetype,
+#ifdef CONFIG_MEMORY_ISOLATION
+ if (migratetype == MIGRATE_ISOLATE)
+ set_pageblock_isolate(page);
+ else
+#endif
+ {
+ if (get_pageblock_isolate(page))
+ clear_pageblock_isolate(page);
+ set_pfnblock_flags_mask(page, (unsigned long)migratetype,
page_to_pfn(page), MIGRATETYPE_MASK);
+ }
}
#ifdef CONFIG_DEBUG_VM
--
2.45.2
