2020-11-10 20:00:30

by Roman Gushchin

Subject: [PATCH 1/2] mm: slub: call account_slab_page() after slab page initialization

It's convenient to have page->objects initialized before calling
into account_slab_page(). In particular, this information can be
used to pre-alloc the obj_cgroup vector.

Let's call account_slab_page() a bit later, after the initialization
of page->objects.

This commit doesn't bring any functional change, but is required for
further optimizations.

Signed-off-by: Roman Gushchin <[email protected]>
---
mm/slub.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/mm/slub.c b/mm/slub.c
index 8c9fa24ebbf3..ccdbb62e025d 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -1622,9 +1622,6 @@ static inline struct page *alloc_slab_page(struct kmem_cache *s,
else
page = __alloc_pages_node(node, flags, order);

- if (page)
- account_slab_page(page, order, s);
-
return page;
}

@@ -1777,6 +1774,8 @@ static struct page *allocate_slab(struct kmem_cache *s, gfp_t flags, int node)

page->objects = oo_objects(oo);

+ account_slab_page(page, oo_order(oo), s, flags);
+
page->slab_cache = s;
__SetPageSlab(page);
if (page_is_pfmemalloc(page))
--
2.26.2

2020-11-12 15:24:24

by Johannes Weiner

Subject: Re: [PATCH 1/2] mm: slub: call account_slab_page() after slab page initialization

On Tue, Nov 10, 2020 at 11:57:52AM -0800, Roman Gushchin wrote:
> It's convenient to have page->objects initialized before calling
> into account_slab_page(). In particular, this information can be
> used to pre-alloc the obj_cgroup vector.
>
> Let's call account_slab_page() a bit later, after the initialization
> of page->objects.
>
> This commit doesn't bring any functional change, but is required for
> further optimizations.
>
> Signed-off-by: Roman Gushchin <[email protected]>

Acked-by: Johannes Weiner <[email protected]>

2020-11-17 17:20:59

by Shakeel Butt

Subject: Re: [PATCH 1/2] mm: slub: call account_slab_page() after slab page initialization

On Tue, Nov 10, 2020 at 11:58 AM Roman Gushchin <[email protected]> wrote:
>
> It's convenient to have page->objects initialized before calling
> into account_slab_page(). In particular, this information can be
> used to pre-alloc the obj_cgroup vector.
>
> Let's call account_slab_page() a bit later, after the initialization
> of page->objects.
>
> This commit doesn't bring any functional change, but is required for
> further optimizations.
>
> Signed-off-by: Roman Gushchin <[email protected]>

Reviewed-by: Shakeel Butt <[email protected]>