This is a clone of issue OCPBUGS-2596. The following is the description of the original issue:
—
This bug is a backport clone of [Bugzilla Bug 2051443](https://bugzilla.redhat.com/show_bug.cgi?id=2051443). The following is the description of the original bug:
—
Description of problem:

CNF tests oslat runner configures oslat to use all available cpus even though some of them belong to the same cpu core. This causes false spikes.

Version-Release number of selected component (if applicable):

All

How reproducible:

Always, by following documentation on HT enabled nodes

Steps to Reproduce:
1. Configure OCP cluster using PAO, keep hyper-threading enabled
2. Run oslat according to the docs, request 7 cpus
3. Observe oslat will use one cpu for control thread (OK) and 6 for testing. Those 6 will be for sure threads 0 and 1 from about 3 cpu cores

https://docs.openshift.com/container-platform/4.9/scalability_and_performance/cnf-performance-addon-operator-for-low-latency-nodes.html#cnf-performing-end-to-end-tests-running-oslat

Actual results:

On a machine configured like this:

```
cpu:
reserved: "0,1,32,33"
isolated: "2-31,34-63"

```

Where cpus 0-31 are threads 0 of cores 0-31 and cpus 32-63 are the secondary threads (thread 1) of the same cores.

```
cat <<EOF > run-cnf-tests.sh
sudo -E podman run --authfile ./pull_secret.txt -v $(pwd)/:/kubeconfig \
--dns 10.20.129.82 \
-e ROLE_WORKER_CNF=master \
-e CLEAN_PERFORMANCE_PROFILE="false" \
-e KUBECONFIG=/kubeconfig/kubeconfig \
-e LATENCY_TEST_RUN=true -e DISCOVERY_MODE=true -e LATENCY_TEST_CPUS=7 -e LATENCY_TEST_RUNTIME=600 -e MAXIMUM_LATENCY=20 \
registry.redhat.com/openshift4/cnf-tests-rhel8:v4.9 \
/usr/bin/test-run.sh -ginkgo.focus="oslat"
EOF

1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. OUTPUT ######################################
                                                   $ oc logs oslat-kwks5
                                                   I0203 14:55:43.363056 1 node.go:37] Environment information: /proc/cmdline: BOOT_IMAGE=(hd0,gpt3)/ostree/rhcos-22582544502f700ca41c79366c3dee5737c2ee491485c0cecb5ba19d7151b5e7/vmlinuz-4.18.0-305.30.1.el8_4.x86_64 random.trust_cpu=on console=tty0 console=ttyS0,115200n8 ignition.platform.id=metal ostree=/ostree/boot.1/rhcos/22582544502f700ca41c79366c3dee5737c2ee491485c0cecb5ba19d7151b5e7/0 ip=ens43f0:dhcp root=UUID=efae0a7f-874e-411d-b4ce-a9a51a1622a7 rw rootflags=prjquota skew_tick=1 nohz=on rcu_nocbs=2-31,34-63 tuned.non_isolcpus=00000003,00000003 intel_pstate=disable nosoftlockup tsc=nowatchdog intel_iommu=on iommu=pt isolcpus=managed_irq,2-31,34-63 systemd.cpu_affinity=0,1,32,33 default_hugepagesz=1G hugepagesz=1G hugepages=50 idle=poll rcupdate.rcu_normal_after_boot=0 nohz_full=2-31,34-63
                                                   I0203 14:55:43.363322 1 node.go:44] Environment information: kernel version 4.18.0-305.30.1.el8_4.x86_64
                                                   I0203 14:55:43.363363 1 main.go:53] Running the oslat command with arguments [--duration 600 --rtprio 1 --cpu-list 3-5,34-36 --cpu-main-thread 2]

[admin@server poc-sno-01]$ oc logs oslat-kwks5 -f
I0203 14:55:43.363056 1 node.go:37] Environment information: /proc/cmdline: BOOT_IMAGE=(hd0,gpt3)/ostree/rhcos-22582544502f700ca41c79366c3dee5737c2ee491485c0cecb5ba19d7151b5e7/vmlinuz-4.18.0-305.30.1.el8_4.x86_64 random.trust_cpu=on console=tty0 console=ttyS0,115200n8 ignition.platform.id=metal ostree=/ostree/boot.1/rhcos/22582544502f700ca41c79366c3dee5737c2ee491485c0cecb5ba19d7151b5e7/0 ip=ens43f0:dhcp root=UUID=efae0a7f-874e-411d-b4ce-a9a51a1622a7 rw rootflags=prjqWorkload: no
Workload mem: 0 (KiB)
Preheat cores: 6

Pre-heat for 1 seconds...
Test starts...
Test completed.

```

Notice this line:

Running the oslat command with arguments [--duration 600 --rtprio 1 --cpu-list 3-5,34-36 --cpu-main-thread 2]

Expected results:

Only threads 3-5 should be used for the test, the remaining cpus should be left idle.

Additional info:

Here is the runner: https://github.com/openshift-kni/cnf-features-deploy/blob/953dcd664f12d39116039e76fead9d83d1d33afb/cnf-tests/pod-utils/oslat-runner/main.go

Here is the similar runner from the performance team: https://github.com/redhat-nfvpe/container-perf-tools/blob/f641d725ffa694b735561b837abc4219753c93d8/oslat/cmd.sh#L70