[SRU][F][aws][PULL] 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
focal:linux-aws (kernel 5.4).

All the SAUCE patches are required to improve swapoff performance after
a successful resume.

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

The following changes since commit 8e57ec411fd5d838ab7d52bf6f6c31a6465b8634:

  UBUNTU: Ubuntu-aws-5.4.0-1005.5 (2020-03-07 13:36:44 -0600)

are available in the Git repository at:

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

for you to fetch changes up to 66efa183cf1c9625d5f4ab08f8b90ae53e3d3009:

  UBUNTU SAUCE [aws]: xen: Only restore the ACPI SCI interrupt in xen_restore_pirqs. (2020-03-10 16:15:55 +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

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.

 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/xen/events.h             |  1 +
 kernel/power/main.c              |  4 +--
 kernel/power/snapshot.c          |  1 -
 kernel/power/swap.c              | 24 +---------------
 mm/swap.c                        |  2 +-
 mm/swap_state.c                  | 60 ++++++----------------------------------
 10 files changed, 75 insertions(+), 78 deletions(-)