Swap delay accounting, include lock_page() delays

The delay incurred in lock_page() should also be accounted in swap delay
accounting

Reported-by: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/mm/memory.c b/mm/memory.c
index 7b0403bfc97fb18c0ca08cd275f30149ca31329a..4bf0b6d0eb2a675bbd1083099448d54979dff304 100644 (file)
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -2084,9 +2084,9 @@ static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma,
                count_vm_event(PGMAJFAULT);
        }
 
-       delayacct_clear_flag(DELAYACCT_PF_SWAPIN);
        mark_page_accessed(page);
        lock_page(page);
+       delayacct_clear_flag(DELAYACCT_PF_SWAPIN);
 
        /*
         * Back out if somebody else already faulted in this pte.