mm: always compile in pte markers

Patch series "mm: Use pte marker for swapin errors".

This series uses the pte marker to replace the swapin error swap entry,
then we save one more swap entry slot for swap devices.  A new pte marker
bit is defined.


This patch (of 2):

The PTE markers code is tiny and now it's enabled for most of the
distributions.  It's fine to keep it as-is, but to make a broader use of
it (e.g.  replacing read error swap entry) it needs to be there always
otherwise we need special code path to take care of !PTE_MARKER case.

It'll be easier just make pte marker always exist.  Use this chance to
extend its usage to anonymous too by simply touching up some of the old
comments, because it'll be used for anonymous pages in the follow up
patches.

Link: https://lkml.kernel.org/r/[email protected]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Peter Xu <[email protected]>
Reviewed-by: Huang Ying <[email protected]>
Reviewed-by: Miaohe Lin <[email protected]>
Acked-by: David Hildenbrand <[email protected]>
Cc: Andrea Arcangeli <[email protected]>
Cc: Naoya Horiguchi <[email protected]>
Cc: Peter Xu <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

0 files changed, 0 insertions, 0 deletions