Commit d4fc5069 authored Jun 07, 2018 by Matthew Wilcox Committed by Linus Torvalds Jun 07, 2018

mm: switch s_mem and slab_cache in struct page

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.

Link: http://lkml.kernel.org/r/20180518194519.3820-5-willy@infradead.org


Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Acked-by: Christoph Lameter <cl@linux.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 1d40a5ea

include/linux/mm_types.h

+2 −2

Original line number	Diff line number	Diff line
		@@ -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

mm/slub.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -1695,6 +1695,7 @@ 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);