Commit af2a1f05 tried clearly separating each condition in
qemuRestoreCgroupState() for the sake of readability, however somehow
one condition body was missing.  That means that the body of the next
condition got executed only if both of there were true, which is
impossible, thus resulting in a dead code and a logic error.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

Instead of setting the value of cpuset.mems once when the domain starts
and then re-calculating the value every time we need to change the child
cgroup values, leave the cgroup alone and rather set the child data
every time there is new cgroup created.  We don't leave any task in the
parent group anyway.  This will ease both current and future code.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

Thanks to that we don't need to drag the pointer everywhere and future
code will get cleaner.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

If the memory mode is specified as 'strict' and with one node, we
get the following error when starting domain.

error: Unable to write to '$cgroup_path/cpuset.mems': Device or resource busy

XML is configured with numatune as follows:
  <numatune>
    <memory mode='strict' nodeset='0'/>
  </numatune>

It's broken by Commit 411cea63
which moved qemuSetupCgroupForEmulator() before setting cpuset.mems
in qemuSetupCgroupPostInit.

Directory '$cgroup_path/emulator/' is created in qemuSetupCgroupForEmulator.
But '$cgroup_path/emulator/cpuset.mems' it not set and has a default value
(all nodes, such as 0-1). Then we setup '$cgroup_path/cpuset.mems' to the
nodemask (in this case it's '0') in qemuSetupCgroupPostInit. It must fail.

This patch makes '$cgroup_path/emulator/cpuset.mems' is set before
'$cgroup_path/cpuset.mems'. The action is similar with that in
qemuDomainSetNumaParamsLive.
Signed-off-by: NWang Rui <moon.wangrui@huawei.com>

If the memory mode in numatune is specified as 'preferred' with one node
(such as nodeset='0'), domain's memory is not all in node 0 absolutely.
Assumption that node 0 doesn't have enough memory, memory can be allocated
on node 1 when qemu process startup. Then if we set cpuset.mems to '0',
it may invoke OOM.

Commit 1a7be8c6 changed the former logic of
checking memory mode in virDomainNumatuneGetNodeset. This patch adds the
check as before.
Signed-off-by: NWang Rui <moon.wangrui@huawei.com>

Commit 4882618e added the code that
requests driver cfg, but forgot to unref it.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

If we don't properly clean up all processes in the
machine-<vmname>.scope systemd won't remove the cgroup and subsequent vm
starts fail with

  'CreateMachine: File exists'

Additional processes can e.g. be added via

  echo $PID > /sys/fs/cgroup/systemd/machine.slice/machine-${VMNAME}.scope/tasks

but there are other cases like

  http://bugs.debian.org/761521

Invoke TerminateMachine to be on the safe side since systemd tracks the
cgroup anyway. This is a noop if all processes have terminated already.

Introduced by commit 0dce260c.

qemuDomainEventQueue was called with qemuDomainObjPrivatePtr instead
of virQEMUDriverPtr.

https://bugzilla.redhat.com/show_bug.cgi?id=1147494

For the new VIR_DOMAIN_EVENT_ID_TUNABLE event we have a bunch of
constants added

   VIR_DOMAIN_EVENT_CPUTUNE_<blah>
   VIR_DOMAIN_EVENT_BLKDEVIOTUNE_<blah>

This naming convention is bad for two reasons

  - There is no common prefix unique for the events to both
    relate them, and distinguish them from other event
    constants

  - The values associated with the constants were chosen
    to match the names used with virConnectGetAllDomainStats
    so having EVENT in the constant name is not applicable in
    that respect

This patch proposes renaming the constants to

    VIR_DOMAIN_TUNABLE_CPU_<blah>
    VIR_DOMAIN_TUNABLE_BLKDEV_<blah>

ie, given them a common VIR_DOMAIN_TUNABLE prefix.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Now we have universal tunable event so we can use it for reporting
changes to user. The cputune values will be prefixed with "cputune" to
distinguish it from other tunable events.
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Plug a memory leak and silence a warning.

Change "i+1" to "i + 1"

In order to support cpuset setting, introduce qemuSetupCgroupIOThreadsPin
and qemuSetupCgroupForIOThreads to mimic the existing Vcpu API's.

These will support having an 'iotrhreadpin' element in the 'cpuset' in
order to pin named IOThreads to specific CPU's. The IOThread pin names
will follow the IOThread naming scheme starting at 1 (eg "iothread1")
up through an including the def->iothreads value.

Libvirt documents that the default entropy source for the 'random'
backend of a RNG device is /dev/random. Instead of storing and
propagating NULL across our code and checking it in multiple places fill
the default in the post parse callback and use that in the other places.

qemu supports adding multiple RNG devices. This patch allows libvirt to
support this.

The "random" backend for virtio-rng can be started with no path
specified which equals to /dev/random. The cgroup code didn't consider
this and called few of the functions with NULL resulting into:

 $ virsh start rng-vm
 error: Failed to start domain rng-vm
 error: Path '(null)' is not accessible: Bad address

Problem introduced by commit c6320d34

Create the structures and API's to hold and manage the iSCSI host device.
This extends the 'scsi_host' definitions added in commit id '5c811dce'.
A future patch will add the XML parsing, but that code requires some
infrastructure to be in place first in order to handle the differences
between a 'scsi_host' and an 'iSCSI host' device.

Split virDomainHostdevSubsysSCSI further. In preparation for having
either SCSI or iSCSI data, create a union in virDomainHostdevSubsysSCSI
to contain just a virDomainHostdevSubsysSCSIHost to describe the
'scsi_host' host device

Create a separate typedef for the hostdev union data describing SCSI
Then adjust the code to use the new pointer

Create a separate typedef for the hostdev union data describing PCI.
Then adjust the code to use the new pointer

Create a separate typedef for the hostdev union data describing USB.
Then adjust the code to use the new pointer

When domain is started with numatune memory mode strict and the
nodeset does not include host NUMA node with DMA and DMA32 zones, KVM
initialization fails.  This is because cgroup restrict even kernel
allocations.  We are already doing numa_set_membind() which does the
same thing, only it does not restrict kernel allocations.

This patch leaves the userspace numa_set_membind() in place and moves
the cpuset.mems setting after the point where monitor comes up, but
before vcpu and emulator sub-groups are created.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

There were numerous places where numatune configuration (and thus
domain config as well) was changed in different ways.  On some
places this even resulted in persistent domain definition not to be
stable (it would change with daemon's restart).

In order to uniformly change how numatune config is dealt with, all
the internals are now accessible directly only in numatune_conf.c and
outside this file accessors must be used.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

Since there was already public virDomainNumatune*, I changed the
private virNumaTune to match the same, so all the uses are unified and
public API is kept:

s/vir\(Domain\)\?Numa[tT]une/virDomainNumatune/g

then shrunk long lines, and mainly functions, that were created after
that:

sed -i 's/virDomainNumatuneMemPlacementMode/virDomainNumatunePlacement/g'

And to cope with the enum name, I haad to change the constants as
well:

s/VIR_NUMA_TUNE_MEM_PLACEMENT_MODE/VIR_DOMAIN_NUMATUNE_PLACEMENT/g

Last thing I did was at least a little shortening of already long
name:

s/virDomainNumatuneDef/virDomainNumatune/g
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

When creating cgroups for vcpu and emulator threads whilst starting a
domain, we explicitly skip creating those cgroups in case priv->cgroup
is NULL (cgroups not supported) because SetAffinity() serves the same
purpose.  If the host supports only some cgroups (the ones we need are
either unmounted or disabled in qemu.conf), we error out with weird
message even though we could continue starting the domain.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1097028Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

Only the top level gets writes, so the rest of the backing chain
requires only read-only access.

Add functions that will allow to set all the required cgroup stuff on
individual images taking a virStorageSourcePtr. Also convert functions
designed to setup whole backing chain to take advantage of the change.

In the future we might need to track state of individual images. Move
the readonly and shared flags to the virStorageSource struct so that we
can keep them in a per-image basis.

It already reports an error if STRDUP fails.

In the f56c773b we've made the substitution but forgot to fix one
comment which is still referring to the old name. This may be
potentially misleading.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

Fix minor typos in source comments
Signed-off-by: NEric Blake <eblake@redhat.com>

Since it is an abbreviation, USB should always be fully
capitalized or full lower case, never Usb.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Since it is an abbreviation, SCSI should always be fully
capitalized or full lower case, never Scsi.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Currently, the Linux kernel treats values of '0' and '1' as
the minimum of 2. Values larger than the maximum are changed
to the maximum.

Re-reading the shares value after setting it reflects this in
the live domain XML.

Currently, <cputune><shares>0</shares></cputune> is treated
as if it were not specified.

Treat is as a valid value if it was explicitly specified
and write it to the cgroups.