From: Mike Kravetz <mike.kravetz@xxxxxxxxxx> Subject: hugetlb: convert PageHugeTemporary() to HPageTemporary flag Use new hugetlb specific HPageTemporary flag to replace the PageHugeTemporary() interfaces. PageHugeTemporary does contain a PageHuge() check. However, this interface is only used within hugetlb code where we know we are dealing with a hugetlb page. Therefore, the check can be eliminated. Link: https://lkml.kernel.org/r/20210122195231.324857-5-mike.kravetz@xxxxxxxxxx Signed-off-by: Mike Kravetz <mike.kravetz@xxxxxxxxxx> Reviewed-by: Oscar Salvador <osalvador@xxxxxxx> Reviewed-by: Muchun Song <songmuchun@xxxxxxxxxxxxx> Acked-by: Michal Hocko <mhocko@xxxxxxxx> Cc: David Hildenbrand <david@xxxxxxxxxx> Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx> Cc: Miaohe Lin <linmiaohe@xxxxxxxxxx> Cc: Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/hugetlb.h | 6 ++++++ mm/hugetlb.c | 36 +++++++----------------------------- 2 files changed, 13 insertions(+), 29 deletions(-) --- a/include/linux/hugetlb.h~hugetlb-convert-pagehugetemporary-to-hpagetemporary-flag +++ a/include/linux/hugetlb.h @@ -483,10 +483,15 @@ unsigned long hugetlb_get_unmapped_area( * HPG_migratable - Set after a newly allocated page is added to the page * cache and/or page tables. Indicates the page is a candidate for * migration. + * HPG_temporary - - Set on a page that is temporarily allocated from the buddy + * allocator. Typically used for migration target pages when no pages + * are available in the pool. The hugetlb free page path will + * immediately free pages with this flag set to the buddy allocator. */ enum hugetlb_page_flags { HPG_restore_reserve = 0, HPG_migratable, + HPG_temporary, __NR_HPAGEFLAGS, }; @@ -530,6 +535,7 @@ static inline void ClearHPage##uname(str */ HPAGEFLAG(RestoreReserve, restore_reserve) HPAGEFLAG(Migratable, migratable) +HPAGEFLAG(Temporary, temporary) #ifdef CONFIG_HUGETLB_PAGE --- a/mm/hugetlb.c~hugetlb-convert-pagehugetemporary-to-hpagetemporary-flag +++ a/mm/hugetlb.c @@ -1364,28 +1364,6 @@ struct hstate *size_to_hstate(unsigned l return NULL; } -/* - * Internal hugetlb specific page flag. Do not use outside of the hugetlb - * code - */ -static inline bool PageHugeTemporary(struct page *page) -{ - if (!PageHuge(page)) - return false; - - return (unsigned long)page[2].mapping == -1U; -} - -static inline void SetPageHugeTemporary(struct page *page) -{ - page[2].mapping = (void *)-1U; -} - -static inline void ClearPageHugeTemporary(struct page *page) -{ - page[2].mapping = NULL; -} - static void __free_huge_page(struct page *page) { /* @@ -1433,9 +1411,9 @@ static void __free_huge_page(struct page if (restore_reserve) h->resv_huge_pages++; - if (PageHugeTemporary(page)) { + if (HPageTemporary(page)) { list_del(&page->lru); - ClearPageHugeTemporary(page); + ClearHPageTemporary(page); update_and_free_page(h, page); } else if (h->surplus_huge_pages_node[nid]) { /* remove the page from active list */ @@ -1869,7 +1847,7 @@ static struct page *alloc_surplus_huge_p * codeflow */ if (h->surplus_huge_pages >= h->nr_overcommit_huge_pages) { - SetPageHugeTemporary(page); + SetHPageTemporary(page); spin_unlock(&hugetlb_lock); put_page(page); return NULL; @@ -1900,7 +1878,7 @@ static struct page *alloc_migrate_huge_p * We do not account these pages as surplus because they are only * temporary and will be released properly on the last reference */ - SetPageHugeTemporary(page); + SetHPageTemporary(page); return page; } @@ -5625,12 +5603,12 @@ void move_hugetlb_state(struct page *old * here as well otherwise the global surplus count will not match * the per-node's. */ - if (PageHugeTemporary(newpage)) { + if (HPageTemporary(newpage)) { int old_nid = page_to_nid(oldpage); int new_nid = page_to_nid(newpage); - SetPageHugeTemporary(oldpage); - ClearPageHugeTemporary(newpage); + SetHPageTemporary(oldpage); + ClearHPageTemporary(newpage); spin_lock(&hugetlb_lock); if (h->surplus_huge_pages_node[old_nid]) { _