path: root/mm/nommu.c
diff options
authorMichel Lespinasse <walken@google.com>2013-02-22 16:35:56 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2013-02-23 17:50:23 -0800
commit240aadeedc4a89fc44623f8ce4ca46bda73db07e (patch)
treee12cc254f2e78560837e5d454fdbe9b5d9e05c5c /mm/nommu.c
parentmm: use long type for page counts in mm_populate() and get_user_pages() (diff)
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 <walken@google.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Rik van Riel <riel@redhat.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to '')
1 files changed, 4 insertions, 2 deletions
diff --git a/mm/nommu.c b/mm/nommu.c
index 6ab706608492..da0d210fd403 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -1819,9 +1819,11 @@ SYSCALL_DEFINE5(mremap, unsigned long, addr, unsigned long, old_len,
return ret;
-struct page *follow_page(struct vm_area_struct *vma, unsigned long address,
- unsigned int foll_flags)
+struct page *follow_page_mask(struct vm_area_struct *vma,
+ unsigned long address, unsigned int flags,
+ unsigned int *page_mask)
+ *page_mask = 0;
return NULL;