ich777/linux_media
1
0
Fork 0
mirror of https://github.com/tbsdtv/linux_media.git synced 2025-07-23 12:43:29 +02:00
Code Issues Packages Projects Releases Wiki Activity

mm: convert total_compound_mapcount() to folio_total_mapcount()

Browse Source 
Instead of enforcing that the argument must be a head page by naming,
enforce it with the compiler by making it a folio.  Also rename the
counter in struct folio from _compound_mapcount to _entire_mapcount.

Link: https://lkml.kernel.org/r/20230111142915.1001531-5-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 14:28:50 +00:00
committed by Andrew Morton
parent 6eee1a0062
commit b14224fbea
3 changed files with 16 additions and 17 deletions
Download Patch File Download Diff File Expand all files Collapse all files

21
mm/rmap.c
View File

@@ -1078,27 +1078,26 @@ int pfn_mkclean_range(unsigned long pfn, unsigned long nr_pages, pgoff_t pgoff,
return page_vma_mkclean_one(&pvmw);
}
int total_compound_mapcount(struct page *head)
int folio_total_mapcount(struct folio *folio)
{
struct folio *folio = (struct folio *)head;
int mapcount = head_compound_mapcount(head);
int nr_subpages;
int mapcount = folio_entire_mapcount(folio);
int nr_pages;
int i;
/* In the common case, avoid the loop when no subpages mapped by PTE */
/* In the common case, avoid the loop when no pages mapped by PTE */
if (folio_nr_pages_mapped(folio) == 0)
return mapcount;
/*
* Add all the PTE mappings of those subpages mapped by PTE.
* Limit the loop, knowing that only subpages_mapcount are mapped?
* Add all the PTE mappings of those pages mapped by PTE.
* Limit the loop to folio_nr_pages_mapped()?
* Perhaps: given all the raciness, that may be a good or a bad idea.
*/
nr_subpages = thp_nr_pages(head);
for (i = 0; i < nr_subpages; i++)
mapcount += atomic_read(&head[i]._mapcount);
nr_pages = folio_nr_pages(folio);
for (i = 0; i < nr_pages; i++)
mapcount += atomic_read(&folio_page(folio, i)->_mapcount);
/* But each of those _mapcounts was based on -1 */
mapcount += nr_subpages;
mapcount += nr_pages;
return mapcount;
}