[cgroups] Collect cgroup information per process

[jcastill]

Collect cgroup information for each process

Related: #3799

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[packit-as-a-service]

Congratulations! One of the builds has completed. 🍾

You can install the built RPMs by following these steps:

• sudo yum install -y dnf-plugins-core on RHEL 8
• sudo dnf install -y dnf-plugins-core on Fedora
• dnf copr enable packit/sosreport-sos-3801
• And now you can install the packages.

Please note that the RPMs should be used only in a testing environment.

[jcastill]

I've tested this and it works, but this will go through all subdirs of /proc, and only collects 'cgroup' when it finds it.
We do something similar but more elegantly in the 'process' plugin:

sos/sos/report/plugins/process.py

Lines 52 to 58 in 96e4d79

	self.add_copy_spec([
	f"/proc/{proc}/status",
	f"/proc/{proc}/cpuset",
	f"/proc/{proc}/oom_*",
	f"/proc/{proc}/stack",
	f"/proc/{proc}/limits",
	])

So my question is, is my approach good enough, or should I use the one in the process plugin gathering the PID entries with:

procs = [p for p in self.listdir("/proc") if re.match("[0-9]", p)]

Then iterating through them?

[TurboTurtle]

/proc/[0-9]*/cgroup

[samuelkarp]

Thank you!