Commit a52c6330 authored by Alex Shi (Tencent)'s avatar Alex Shi (Tencent) Committed by Vlastimil Babka
Browse files

mm/memcg: alignment memcg_data define condition 



commit 21c690a3 ("mm: introduce slabobj_ext to support slab object
extensions") changed the folio/page->memcg_data define condition from
MEMCG to SLAB_OBJ_EXT. This action make memcg_data exposed while !MEMCG.

As Vlastimil Babka suggested, let's add _unused_slab_obj_exts for
SLAB_MATCH for slab.obj_exts while !MEMCG. That could resolve the match
issue, clean up the feature logical.

Signed-off-by: default avatarAlex Shi (Tencent) <alexs@kernel.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Yoann Congal <yoann.congal@smile.fr>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: default avatarVlastimil Babka <vbabka@suse.cz>
parent 7b1fdf2b

include/linux/mm_types.h

+7 −2
Original line number Diff line number Diff line
@@ -169,8 +169,10 @@ struct page { 
	/* Usage count. *DO NOT USE DIRECTLY*. See page_ref.h */

	atomic_t _refcount;



#ifdef CONFIG_SLAB_OBJ_EXT

#ifdef CONFIG_MEMCG

	unsigned long memcg_data;

#elif defined(CONFIG_SLAB_OBJ_EXT)

	unsigned long _unused_slab_obj_exts;

#endif



	/*
@@ -298,6 +300,7 @@ typedef struct { 
 * @_hugetlb_cgroup_rsvd: Do not use directly, use accessor in hugetlb_cgroup.h.

 * @_hugetlb_hwpoison: Do not use directly, call raw_hwp_list_head().

 * @_deferred_list: Folios to be split under memory pressure.

 * @_unused_slab_obj_exts: Placeholder to match obj_exts in struct slab.

 *

 * A folio is a physically, virtually and logically contiguous set

 * of bytes.  It is a power-of-two in size, and it is aligned to that
@@ -332,8 +335,10 @@ struct folio { 
			};

			atomic_t _mapcount;

			atomic_t _refcount;

#ifdef CONFIG_SLAB_OBJ_EXT

#ifdef CONFIG_MEMCG

			unsigned long memcg_data;

#elif defined(CONFIG_SLAB_OBJ_EXT)

			unsigned long _unused_slab_obj_exts;

#endif

#if defined(WANT_PAGE_VIRTUAL)

			void *virtual;

mm/slab.h

+3 −1
Original line number Diff line number Diff line
@@ -97,8 +97,10 @@ struct slab { 
SLAB_MATCH(flags, __page_flags);

SLAB_MATCH(compound_head, slab_cache);	/* Ensure bit 0 is clear */

SLAB_MATCH(_refcount, __page_refcount);

#ifdef CONFIG_SLAB_OBJ_EXT

#ifdef CONFIG_MEMCG

SLAB_MATCH(memcg_data, obj_exts);

#elif defined(CONFIG_SLAB_OBJ_EXT)

SLAB_MATCH(_unused_slab_obj_exts, obj_exts);

#endif

#undef SLAB_MATCH

static_assert(sizeof(struct slab) <= sizeof(struct page));