[v2,0/3] mm/page_reporting: Make page reporting work on arm64 with 64KB page size

Message

Gavin Shan June 22, 2021, 7:49 a.m. UTC

The page reporting threshold is currently equal to @pageblock_order, which
is 13 and 512MB on arm64 with 64KB base page size selected. The page
reporting won't be triggered if the freeing page can't come up with a free
area like that huge. The condition is hard to be met, especially when the
system memory becomes fragmented.

This series intends to solve the issue by having page reporting threshold
as 5 (2MB) on arm64 with 64KB base page size. The patches are organized as:

   PATCH[1/3] Fix some coding style in __page_reporting_request().
   PATCH[2/3] Allows the device driver (e.g. virtio_balloon) to specify
              the page reporting order when the device info is registered.
   PATCH[3/3] Specifies the page reporting order to 5, corresponding to
              2MB in size on ARM64 when 64KB base page size is used.

Changelog
=========
v2:
   * Rewrite the patches to let device driver specify the page reporting
     order.                                                    (Alex)

Gavin Shan (3):
  mm/page_reporting: Fix code style in __page_reporting_request()
  mm/page_reporting: Allow driver to specify threshold
  virtio_balloon: Specify page reporting order if needed

 drivers/virtio/virtio_balloon.c | 17 +++++++++++++++++
 include/linux/page_reporting.h  |  3 +++
 mm/page_reporting.c             | 18 ++++++++++++------
 mm/page_reporting.h             | 10 ++--------
 4 files changed, 34 insertions(+), 14 deletions(-)