Create a new cgroup and move all emulator threads to the new cgroup.
And then we can do the other things:
1. limit only vcpu usage rather than the whole qemu
2. limit for emulator threads(include vhost-net threads)
Signed-off-by: NWen Congyang <wency@cn.fujitsu.com>
Signed-off-by: NTang Chen <tangchen@cn.fujitsu.com>
Signed-off-by: NHu Tao <hutao@cn.fujitsu.com>

Per the FSF address could be changed from time to time, and GNU
recommends the following now: (http://www.gnu.org/licenses/gpl-howto.html)

  You should have received a copy of the GNU General Public License
  along with Foobar.  If not, see <http://www.gnu.org/licenses/>.

This patch removes the explicit FSF address, and uses above instead
(of course, with inserting 'Lesser' before 'General').

Except a bunch of files for security driver, all others are changed
automatically, the copyright for securify files are not complete,
that's why to do it manually:

  src/security/security_selinux.h
  src/security/security_driver.h
  src/security/security_selinux.c
  src/security/security_apparmor.h
  src/security/security_apparmor.c
  src/security/security_driver.c

Like for 'static' placement, when the memory policy mode is
'strict', set the memory policy by writing the advisory nodeset
returned from numad to cgroup file cpuset.mems,

This patch implements period and quota tunable XML configuration and parsing.
A quota or period of zero will be simply ignored.

Clang warned about a dead assignment.  In the process, I noticed
that we are only using the function for a bool value.  I audited
all other callers in qemu_{migration,cgroup,driver,hotplug), and
all were making the call in a bool context.

Also, do bounds checking on the argument.

* src/qemu/qemu_cgroup.c (qemuSetupCgroup): Delete dead
assignment.
(qemuCgroupControllerActive): Change return type to bool.
* src/qemu/qemu_cgroup.h (qemuCgroupControllerActive): Likewise.

* src/qemu/qemu_cgroup.h (struct qemuCgroupData): New helper type.
(qemuSetupDiskPathAllow, qemuSetupChardevCgroup)
(qemuTeardownDiskPathDeny): Drop unneeded prototypes.
(qemuSetupDiskCgroup, qemuTeardownDiskCgroup): Adjust prototype.
* src/qemu/qemu_cgroup.c
(qemuSetupDiskPathAllow, qemuSetupChardevCgroup)
(qemuTeardownDiskPathDeny): Mark static and use new type.
(qemuSetupHostUsbDeviceCgroup): Use new type.
(qemuSetupDiskCgroup): Alter signature.
(qemuSetupCgroup): Adjust caller.
* src/qemu/qemu_hotplug.c (qemuDomainAttachHostUsbDevice)
(qemuDomainDetachPciDiskDevice, qemuDomainDetachSCSIDiskDevice):
Likewise.
* src/qemu/qemu_driver.c (qemudDomainAttachDevice)
(qemuDomainUpdateDeviceFlags): Likewise.

The QEMU driver file is far too large. Move all the cgroup
helper code out into a separate file. No functional change.

* src/qemu/qemu_cgroup.c, src/qemu/qemu_cgroup.h,
  src/Makefile.am: Add cgroup helper file
* src/qemu/qemu_driver.c: Delete cgroup code