From: Matthew Wilcox <mawilcox@xxxxxxxxxxxxx>
This will allow us to store slub's counters in the same bits as slab's
s_mem. slub now needs to set page->mapping to NULL as it frees the page,
just like slab does.
Signed-off-by: Matthew Wilcox <mawilcox@xxxxxxxxxxxxx>
---
include/linux/mm_types.h | 4 ++--
mm/slub.c | 1 +
2 files changed, 3 insertions(+), 2 deletions(-)
diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index 41828fb34860..e97a310a6abe 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -83,7 +83,7 @@ struct page {
/* See page-flags.h for the definition of PAGE_MAPPING_FLAGS */
struct address_space *mapping;
- void *s_mem; /* slab first object */
+ struct kmem_cache *slab_cache; /* SL[AU]B: Pointer to slab */
atomic_t compound_mapcount; /* first tail page */
/* page_deferred_list().next -- second tail page */
};
@@ -194,7 +194,7 @@ struct page {
spinlock_t ptl;
#endif
#endif
- struct kmem_cache *slab_cache; /* SL[AU]B: Pointer to slab */
+ void *s_mem; /* slab first object */
};
#ifdef CONFIG_MEMCG
diff --git a/mm/slub.c b/mm/slub.c
index e938184ac847..7fc13c46e975 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -1690,6 +1690,7 @@ static void __free_slab(struct kmem_cache *s, struct page *page)
__ClearPageSlab(page);
page_mapcount_reset(page);
+ page->mapping = NULL;
if (current->reclaim_state)
current->reclaim_state->reclaimed_slab += pages;
memcg_uncharge_slab(page, order, s);
--
2.17.0
