From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx> Subject: mm/vmscan: allow arbitrary sized pages to be paged out Remove the assumption that a compound page has HPAGE_PMD_NR pins from the page cache. Link: https://lkml.kernel.org/r/20200908195539.25896-12-willy@xxxxxxxxxxxxx Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> Acked-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> Acked-by: "Huang, Ying" <ying.huang@xxxxxxxxx> Reviewed-by: SeongJae Park <sjpark@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/vmscan.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) --- a/mm/vmscan.c~mm-vmscan-allow-arbitrary-sized-pages-to-be-paged-out +++ a/mm/vmscan.c @@ -725,8 +725,7 @@ static inline int is_page_cache_freeable * that isolated the page, the page cache and optional buffer * heads at page->private. */ - int page_cache_pins = PageTransHuge(page) && PageSwapCache(page) ? - HPAGE_PMD_NR : 1; + int page_cache_pins = thp_nr_pages(page); return page_count(page) - page_has_private(page) == 1 + page_cache_pins; } _
