lkml.org 
[lkml]   [2020]   [May]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH] mm/page_alloc: Restrict and formalize compound_page_dtors[]
From
Date
On 18.05.20 11:59, Anshuman Khandual wrote:
> Restrict elements in compound_page_dtors[] array per NR_COMPOUND_DTORS and
> explicitly position them according to enum compound_dtor_id. This improves
> protection against possible misalignment between compound_page_dtors[] and
> enum compound_dtor_id later on.
>
> Cc: Andrew Morton <akpm@linux-foundation.org>
> Cc: linux-mm@kvack.org
> Cc: linux-kernel@vger.kernel.org
> Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
> ---
> include/linux/mm.h | 2 +-
> mm/page_alloc.c | 10 +++++-----
> 2 files changed, 6 insertions(+), 6 deletions(-)
>
> diff --git a/include/linux/mm.h b/include/linux/mm.h
> index 688558c57751..d1bd7736a5e5 100644
> --- a/include/linux/mm.h
> +++ b/include/linux/mm.h
> @@ -856,7 +856,7 @@ enum compound_dtor_id {
> #endif
> NR_COMPOUND_DTORS,
> };
> -extern compound_page_dtor * const compound_page_dtors[];
> +extern compound_page_dtor * const compound_page_dtors[NR_COMPOUND_DTORS];
>
> static inline void set_compound_page_dtor(struct page *page,
> enum compound_dtor_id compound_dtor)
> diff --git a/mm/page_alloc.c b/mm/page_alloc.c
> index cef05d3a23f5..2e4c23b34940 100644
> --- a/mm/page_alloc.c
> +++ b/mm/page_alloc.c
> @@ -302,14 +302,14 @@ const char * const migratetype_names[MIGRATE_TYPES] = {
> #endif
> };
>
> -compound_page_dtor * const compound_page_dtors[] = {
> - NULL,
> - free_compound_page,
> +compound_page_dtor * const compound_page_dtors[NR_COMPOUND_DTORS] = {
> + [NULL_COMPOUND_DTOR] = NULL,
> + [COMPOUND_PAGE_DTOR] = free_compound_page,
> #ifdef CONFIG_HUGETLB_PAGE
> - free_huge_page,
> + [HUGETLB_PAGE_DTOR] = free_huge_page,
> #endif
> #ifdef CONFIG_TRANSPARENT_HUGEPAGE
> - free_transhuge_page,
> + [TRANSHUGE_PAGE_DTOR] = free_transhuge_page,
> #endif
> };
>
>

Reviewed-by: David Hildenbrand <david@redhat.com>

--
Thanks,

David / dhildenb

\
 
 \ /
  Last update: 2020-05-18 12:05    [W:0.037 / U:0.052 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site