[SRU][D / B aws-edge][aws][PULL v3] proper hibernation support

[Andrea Righi]

BugLink: https://bugs.launchpad.net/bugs/1858618
BugLink: https://bugs.launchpad.net/bugs/1831940

The following patches are required to properly support hibernation with
bionic:linux-aws-edge / disco:linux-aws.

The most important patch is "PM / hibernate: memory_bm_find_bit():
Tighten node optimisation": this is a very critical bug fix for
hibernation that prevents potential memory corruptions on resume.

All the other hibernation-related SAUCE patches are required to improve
swapoff performance after a successful resume.

Moreover, some Xen-related patches have been included (ported from
bionic:linux-aws).

All these patches have been tested in the AWS environment with positive
results.

Changes in v3:
 - added missing BugLink information
 - added "cherry picked" lines for upstream patches

Changes in v2:
 - added missing Xen-related patches
 - added pm_async and image_size tunings

The following changes since commit 0f84693e79c7c596ac56d952851e0b9527679689:

  UBUNTU: Ubuntu-aws-edge-5.0.0-1019.21~18.04.1 (2019-10-03 00:49:16 -0400)

are available in the Git repository at:

  git://git.launchpad.net/~arighi/+git/bionic-linux aws-edge-arighi

for you to fetch changes up to b4aa4088c1582fa27c63532788b4d7087b1bbafa:

  UBUNTU SAUCE [aws]: xen: Only restore the ACPI SCI interrupt in xen_restore_pirqs. (2020-02-11 08:32:11 +0100)

----------------------------------------------------------------
Anchal Agarwal (1):
      UBUNTU SAUCE [aws]: ACPICA: Enable sleep button on ACPI legacy wake

Andrea Righi (4):
      UBUNTU SAUCE [aws] PM / hibernate: reduce memory pressure during image writing
      UBUNTU SAUCE [aws]: mm: swap: improve swap readahead heuristic
      UBUNTU SAUCE [aws]: PM / hibernate: make sure pm_async is always disabled
      UBUNTU SAUCE [aws]: PM / hibernate: set image_size to 0 by default

Andy Whitcroft (1):
      PM / hibernate: memory_bm_find_bit(): Tighten node optimisation

Eduardo Valentin (1):
      UBUNTU SAUCE [aws]: block: xen-blkfront: consider new dom0 features on restore

Frank van der Linden (2):
      UBUNTU SAUCE [aws]: xen: restore pirqs on resume from hibernation.
      UBUNTU SAUCE [aws]: xen: Only restore the ACPI SCI interrupt in xen_restore_pirqs.

Vineeth Remanan Pillai (2):
      mm: refactor swap-in logic out of shmem_getpage_gfp
      mm: rid swapoff of quadratic complexity

 arch/x86/xen/suspend.c           |   2 +
 drivers/acpi/acpica/hwsleep.c    |  11 +
 drivers/block/xen-blkfront.c     |   3 +
 drivers/xen/events/events_base.c |  45 +++
 include/linux/frontswap.h        |   7 +
 include/linux/shmem_fs.h         |   3 +-
 include/xen/events.h             |   1 +
 kernel/power/main.c              |   4 +-
 kernel/power/snapshot.c          |  10 +-
 kernel/power/swap.c              |  24 +-
 mm/shmem.c                       | 716 +++++++++++++++++++++------------------
 mm/swap.c                        |   2 +-
 mm/swap_state.c                  |  60 +---
 mm/swapfile.c                    | 433 +++++++++--------------
 14 files changed, 646 insertions(+), 675 deletions(-)