diff options
| author | Huang Ying <ying.huang@intel.com> | 2017-09-06 16:22:19 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2017-09-06 17:27:27 -0700 |
| commit | ba3c4ce6def4915093be80585ff69f780630f32f (patch) | |
| tree | 3fa890d652981cc54c5ebd7ea59cfc134fad4a6c /mm/memory.c | |
| parent | e07098294adfd03d582af7626752255e3d170393 (diff) | |
mm, THP, swap: make reuse_swap_page() works for THP swapped out
After supporting to delay THP (Transparent Huge Page) splitting after
swapped out, it is possible that some page table mappings of the THP are
turned into swap entries. So reuse_swap_page() need to check the swap
count in addition to the map count as before. This patch done that.
In the huge PMD write protect fault handler, in addition to the page map
count, the swap count need to be checked too, so the page lock need to
be acquired too when calling reuse_swap_page() in addition to the page
table lock.
[ying.huang@intel.com: silence a compiler warning]
Link: http://lkml.kernel.org/r/87bmnzizjy.fsf@yhuang-dev.intel.com
Link: http://lkml.kernel.org/r/20170724051840.2309-4-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Shaohua Li <shli@kernel.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Ross Zwisler <ross.zwisler@intel.com> [for brd.c, zram_drv.c, pmem.c]
Cc: Vishal L Verma <vishal.l.verma@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/memory.c')
| -rw-r--r-- | mm/memory.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/mm/memory.c b/mm/memory.c index 1416485e278c..3dd8bb46391b 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -2619,7 +2619,7 @@ static int do_wp_page(struct vm_fault *vmf) * not dirty accountable. */ if (PageAnon(vmf->page) && !PageKsm(vmf->page)) { - int total_mapcount; + int total_map_swapcount; if (!trylock_page(vmf->page)) { get_page(vmf->page); pte_unmap_unlock(vmf->pte, vmf->ptl); @@ -2634,8 +2634,8 @@ static int do_wp_page(struct vm_fault *vmf) } put_page(vmf->page); } - if (reuse_swap_page(vmf->page, &total_mapcount)) { - if (total_mapcount == 1) { + if (reuse_swap_page(vmf->page, &total_map_swapcount)) { + if (total_map_swapcount == 1) { /* * The page is all ours. Move it to * our anon_vma so the rmap code will |