diff mbox series

[v3] mm/memcg: alignment memcg_data define condition

Message ID 20240712041435.301314-1-alexs@kernel.org (mailing list archive)
State New
Headers show
Series [v3] mm/memcg: alignment memcg_data define condition | expand

Commit Message

alexs@kernel.org July 12, 2024, 4:14 a.m. UTC 
From: "Alex Shi (Tencent)" <alexs@kernel.org>

commit 21c690a349ba ("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_ext for
SLAB_MATCH for slab.obj_exts while !MEMCG. That could resolve the match
issue, clean up the feature logical.

Signed-off-by: Alex 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>
---
 include/linux/mm_types.h | 8 ++++++--
 mm/slab.h                | 4 +++-
 2 files changed, 9 insertions(+), 3 deletions(-)

Comments

Vlastimil Babka July 12, 2024, 7:40 a.m. UTC | #1 
On 7/12/24 6:14 AM, alexs@kernel.org wrote:
> From: "Alex Shi (Tencent)" <alexs@kernel.org>
> 
> commit 21c690a349ba ("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_ext for
> SLAB_MATCH for slab.obj_exts while !MEMCG. That could resolve the match
> issue, clean up the feature logical.
> 
> Signed-off-by: Alex 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>

Thanks, added to slab/for-next
diff mbox series

Patch

diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index ef09c4eef6d3..4ac3abc673d3 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -180,8 +180,10 @@  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_ext;
 #endif
 
 	/*
@@ -343,8 +345,10 @@  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_ext;
 #endif
 #if defined(WANT_PAGE_VIRTUAL)
 			void *virtual;
diff --git a/mm/slab.h b/mm/slab.h
index 3586e6183224..3aae11dde532 100644
--- a/mm/slab.h
+++ b/mm/slab.h
@@ -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_ext, obj_exts);
 #endif
 #undef SLAB_MATCH
 static_assert(sizeof(struct slab) <= sizeof(struct page));