Re: [Crash-utility] list cgroup from crash
On 2023/08/28 15:39, Mathew T wrote:
Hi,
I am trying to figure out if I can extract the values associated with
cgroups from kernel crash dump. I can see "cgorup" is mounted when i
issue "mount" command in crash utility. And it shows mount/superblock
address. How can I further dig down and print the values inside cgroup
fs. Suppose if I want to print "/sys/fs/cgroup/cpu.stat" in the crash
utility!? The extension lscgroup / cgget are not working in latest
kernels.
As far as I know, there is no extension module that can print it with
the recent cgroup implementation.
Also, cgroup fs is a pseudo one. When you read a file in the fs, the
kernel gathers information and prints it. So you need to (1) find out
what is done by reading the file and (2) emulate it with crash commands.
I'm not familiar with cgroup, but maybe it's good to start with
cpu_stat_show() in kernel/cgroup/cgroup.c.
Thanks,
Kazu