Set cpuset for emulator during UpdateContainerResources

[jellonek]

Note: this can not work on dind, as it requires an access to system level cgroup hierarchy, while in dind case it will be limited to only node container hierarchy.

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This change is 

[ivan4th]

Reviewable status: 0 of 1 approvals obtained (waiting on @jellonek)

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pkg/libvirttools/cpusets.go, line 41 at r1 (raw file):

// setting environment variable for vmwrapper with info about to which cpuset it should
// pin itself
func (v *VirtualizationTool) UpdateCpusetsInContainerDefinition(containerID, cpusets string) error {

// UpdateCpusetsInContainerDefinition updates libvirt domain definition for the VM
// setting the environment variable which is used by vmwrapper to pin to the specified cpuset

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pkg/libvirttools/cpusets.go, line 114 at r1 (raw file):

}

func checkIfItsPidOfContainerEmulator(pid, containerID string) (bool, error) {

isEmulatorPid

also, perhaps this can be written as "TODO" for now, but this kind of check is rather weak IMO.

as discussed, should be replaced with reading /run/libvirt/qemu/DOMAIN_NAME.pid in a followup

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pkg/libvirttools/cpusets.go, line 126 at r1 (raw file):

	}

	searchedTerm := "virtlet-" + containerID[:12]

searchTerm

[ivan4th]

Reviewed 9 of 11 files at r1, 2 of 2 files at r2.
Reviewable status: 1 change requests, 0 of 1 approvals obtained (waiting on @jellonek)