[libvirt] [PATCH 0/7] Support cgroups in QEMU driver

[Daniel P. Berrange]

This series of patches introduces cgroups support to the QEMU driver.
At this time it uses the 'devices' controller to whitelist block
devices for QEMU guests to prevent unauthorized access. It uses the
'cpu_shares' controller to allow schedular tunables on a per guest
basis. In the future we should use the 'memory' controller to enforce
the limit set in the balloon driver ie if the guest does not honour
the balloon request, then force the guest into swap, avoiding host
overcommit.

There is also some refactoring of the cgroups code to remove the
assumption that libvirtd is starting in the root cgroup, remove
the requirement that all controllers be active, and allow for use
in non-privileged drivers.

Daniel P. Berrange (7):
  Use enums for cgroup controller types / labels
  Use virFileReadAll/virFileWriteStr for key cgroup read/write helpers
  Make cgroups a little more efficient
  Place every QEMU guest in a private cgroup
  Implement schedular tunables API using cgroups
  Use cgroups for block device whitelisting in QEMU guests
  Refactor cgroups to allow a group per driver to be managed directly

 src/cgroup.c             |  861 ++++++++++++++++++++++++++--------------------
 src/cgroup.h             |   28 +-
 src/libvirt_private.syms |    1 +
 src/lxc_conf.h           |    2 +
 src/lxc_controller.c     |   19 +-
 src/lxc_driver.c         |   25 +-
 src/qemu_conf.h          |    2 +
 src/qemu_driver.c        |  355 ++++++++++++++++++-
 src/util.c               |   27 ++-
 src/util.h               |    2 +
 10 files changed, 904 insertions(+), 420 deletions(-)