From 240aadeedc4a89fc44623f8ce4ca46bda73db07e Mon Sep 17 00:00:00 2001 From: Michel Lespinasse Date: Fri, 22 Feb 2013 16:35:56 -0800 Subject: mm: accelerate mm_populate() treatment of THP pages This change adds a follow_page_mask function which is equivalent to follow_page, but with an extra page_mask argument. follow_page_mask sets *page_mask to HPAGE_PMD_NR - 1 when it encounters a THP page, and to 0 in other cases. __get_user_pages() makes use of this in order to accelerate populating THP ranges - that is, when both the pages and vmas arrays are NULL, we don't need to iterate HPAGE_PMD_NR times to cover a single THP page (and we also avoid taking mm->page_table_lock that many times). Signed-off-by: Michel Lespinasse Cc: Andrea Arcangeli Cc: Rik van Riel Cc: Mel Gorman Cc: Hugh Dickins Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/mm.h | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) (limited to 'include/linux/mm.h') diff --git a/include/linux/mm.h b/include/linux/mm.h index 87b0ef253607..6124f1db50fe 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1629,8 +1629,17 @@ int vm_insert_pfn(struct vm_area_struct *vma, unsigned long addr, int vm_insert_mixed(struct vm_area_struct *vma, unsigned long addr, unsigned long pfn); -struct page *follow_page(struct vm_area_struct *, unsigned long address, - unsigned int foll_flags); +struct page *follow_page_mask(struct vm_area_struct *vma, + unsigned long address, unsigned int foll_flags, + unsigned int *page_mask); + +static inline struct page *follow_page(struct vm_area_struct *vma, + unsigned long address, unsigned int foll_flags) +{ + unsigned int unused_page_mask; + return follow_page_mask(vma, address, foll_flags, &unused_page_mask); +} + #define FOLL_WRITE 0x01 /* check pte is writable */ #define FOLL_TOUCH 0x02 /* mark page accessed */ #define FOLL_GET 0x04 /* do get_page on page */ -- cgit