From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx> Subject: mm: add thp_order This function returns the order of a transparent huge page. It compiles to 0 if CONFIG_TRANSPARENT_HUGEPAGE is disabled. Link: http://lkml.kernel.org/r/20200629151959.15779-4-willy@xxxxxxxxxxxxx Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> Reviewed-by: William Kucharski <william.kucharski@xxxxxxxxxx> Reviewed-by: Zi Yan <ziy@xxxxxxxxxx> Cc: David Hildenbrand <david@xxxxxxxxxx> Cc: Mike Kravetz <mike.kravetz@xxxxxxxxxx> Cc: "Kirill A. Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/huge_mm.h | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) --- a/include/linux/huge_mm.h~mm-add-thp_order +++ a/include/linux/huge_mm.h @@ -258,6 +258,19 @@ static inline spinlock_t *pud_trans_huge else return NULL; } + +/** + * thp_order - Order of a transparent huge page. + * @page: Head page of a transparent huge page. + */ +static inline unsigned int thp_order(struct page *page) +{ + VM_BUG_ON_PGFLAGS(PageTail(page), page); + if (PageHead(page)) + return HPAGE_PMD_ORDER; + return 0; +} + static inline int hpage_nr_pages(struct page *page) { if (unlikely(PageTransHuge(page))) @@ -317,6 +330,12 @@ static inline struct list_head *page_def #define HPAGE_PUD_MASK ({ BUILD_BUG(); 0; }) #define HPAGE_PUD_SIZE ({ BUILD_BUG(); 0; }) +static inline unsigned int thp_order(struct page *page) +{ + VM_BUG_ON_PGFLAGS(PageTail(page), page); + return 0; +} + static inline int hpage_nr_pages(struct page *page) { VM_BUG_ON_PAGE(PageTail(page), page); _
