bianbu-repo-mirror/bianbu-linux-6.6
1
0
Fork 0
mirror of https://gitee.com/bianbu-linux/linux-6.6 synced 2025-04-24 14:07:52 -04:00
Code Issues Projects Releases Packages Wiki Activity Actions

mm: convert page_mapcount() to use folio_entire_mapcount()

Browse source 
Remove a use of head_compound_mapcount().

Link: https://lkml.kernel.org/r/20230111142915.1001531-15-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Matthew Wilcox (Oracle) 2023-01-11 14:29:00 +00:00 • committed by Andrew Morton
parent 46f2722825
commit c97eeb8f26
1 changed files with 13 additions and 9 deletions
Download patch file Download diff file Expand all files Collapse all files

22
include/linux/mm.h
View file

@ -853,22 +853,26 @@ static inline void page_mapcount_reset(struct page *page)
atomic_set(&(page)->_mapcount, -1);
}
/*
* Mapcount of 0-order page; when compound sub-page, includes
* compound_mapcount of compound_head of page.
/**
* page_mapcount() - Number of times this precise page is mapped.
* @page: The page.
*
* Result is undefined for pages which cannot be mapped into userspace.
* The number of times this page is mapped. If this page is part of
* a large folio, it includes the number of times this page is mapped
* as part of that folio.
*
* The result is undefined for pages which cannot be mapped into userspace.
* For example SLAB or special types of pages. See function page_has_type().
* They use this place in struct page differently.
* They use this field in struct page differently.
*/
static inline int page_mapcount(struct page *page)
{
int mapcount = atomic_read(&page->_mapcount) + 1;
if (likely(!PageCompound(page)))
return mapcount;
page = compound_head(page);
return head_compound_mapcount(page) + mapcount;
if (unlikely(PageCompound(page)))
mapcount += folio_entire_mapcount(page_folio(page));
return mapcount;
}
int folio_total_mapcount(struct folio *folio);