pagewalk: fix code comment for THP

Commit bae9c19bf1 ("thp: split_huge_page_mm/vma") changed locking behavior
of walk_page_range().  Thus this patch changes the comment too.

Signed-off-by: KOSAKI Motohiro <[email protected]>
Cc: Naoya Horiguchi <[email protected]>
Cc: Hiroyuki Kamezawa <[email protected]>
Cc: Andrea Arcangeli <[email protected]>
Cc: Matt Mackall <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

diff --git a/mm/pagewalk.c b/mm/pagewalk.c
index f7929406e77661d95bd88129de21a462b60c0be8..2f5cf10ff6607483433cc3a059d28023afa9a042 100644 (file)
--- a/mm/pagewalk.c
+++ b/mm/pagewalk.c
@@ -176,7 +176,8 @@ static int walk_hugetlb_range(struct vm_area_struct *vma,
  * associated range, and a copy of the original mm_walk for access to
  * the ->private or ->mm fields.
  *
- * No locks are taken, but the bottom level iterator will map PTE
+ * Usually no locks are taken, but splitting transparent huge page may
+ * take page table lock. And the bottom level iterator will map PTE
  * directories from highmem if necessary.
  *
  * If any callback returns a non-zero value, the walk is aborted and