Commit 2a4c6719 authored by David Hildenbrand's avatar David Hildenbrand Committed by Liu Shixin
Browse files

mm/rmap: always inline anon/file rmap duplication of a single PTE 

mainline inclusion
from mainline-v6.10-rc1
commit c2e65ebc02fb60b64a1c5689fe2c6f60d0fc1626
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/IAE0PK

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=c2e65ebc02fb60b64a1c5689fe2c6f60d0fc1626

--------------------------------

As we grow the code, the compiler might make stupid decisions and
unnecessarily degrade fork() performance.  Let's make sure to always
inline functions that operate on a single PTE so the compiler will always
optimize out the loop and avoid a function call.

This is a preparation for maintining a total mapcount for large folios.

Link: https://lkml.kernel.org/r/20240409192301.907377-3-david@redhat.com


Signed-off-by: default avatarDavid Hildenbrand <david@redhat.com>
Reviewed-by: default avatarYin Fengwei <fengwei.yin@intel.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Hugh Dickins <hughd@google.com>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Richard Chang <richardycc@google.com>
Cc: Rich Felker <dalias@libc.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLiu Shixin <liushixin2@huawei.com>
parent 55516986

include/linux/rmap.h

+13 −4
Original line number Diff line number Diff line
@@ -344,8 +344,12 @@ static inline void folio_dup_file_rmap_ptes(struct folio *folio, 
{

	__folio_dup_file_rmap(folio, page, nr_pages, RMAP_LEVEL_PTE);

}

#define folio_dup_file_rmap_pte(folio, page) \

	folio_dup_file_rmap_ptes(folio, page, 1)



static __always_inline void folio_dup_file_rmap_pte(struct folio *folio,

		struct page *page)

{

	__folio_dup_file_rmap(folio, page, 1, RMAP_LEVEL_PTE);

}



/**

 * folio_dup_file_rmap_pmd - duplicate a PMD mapping of a page range of a folio
@@ -445,8 +449,13 @@ static inline int folio_try_dup_anon_rmap_ptes(struct folio *folio, 
	return __folio_try_dup_anon_rmap(folio, page, nr_pages, src_vma,

					 RMAP_LEVEL_PTE);

}

#define folio_try_dup_anon_rmap_pte(folio, page, vma) \

	folio_try_dup_anon_rmap_ptes(folio, page, 1, vma)



static __always_inline int folio_try_dup_anon_rmap_pte(struct folio *folio,

		struct page *page, struct vm_area_struct *src_vma)

{

	return __folio_try_dup_anon_rmap(folio, page, 1, src_vma,

					 RMAP_LEVEL_PTE);

}



/**

 * folio_try_dup_anon_rmap_pmd - try duplicating a PMD mapping of a page range