Re: [Suggestion] kernel: cgroup: mount failure in LTP cgroup_regression_test.sh

[Tejun Heo <tj@kernel.org>]

Hello,

Sorry about the delay.

On Fri, Nov 08, 2013 at 04:15:23PM +0800, Chen Gang wrote:
> After simplify, the related operation, environments and output are:
> 
>   [root@gchenlinux tmp]# df -Th | grep cgroup
>   tmpfs                             tmpfs    1001M     0 1001M   0% /sys/fs/cgroup
>   [root@gchenlinux tmp]# lsof | grep cgroup | grep -v grep
>   systemd       1          root    6r      DIR               0,18         0       5998 /sys/fs/cgroup/systemd/system
>   [root@gchenlinux tmp]# cat /proc/cgroups 
>   #subsys_name	hierarchy	num_cgroups	enabled
>   cpuset	3	4	1
>   cpu	4	35	1
>   cpuacct	4	35	1
>   freezer	5	4	1
>   [root@gchenlinux tmp]# mkdir cgroup
>   [root@gchenlinux tmp]# mount -t cgroup -o freezer,cpuacct xxx cgroup/
>   mount: xxx already mounted or cgroup/ busy
> 
> Is it real issue of cgroup? If it is, I will/should continue analyzing.

Hmmm... I'm a bit confused.  What is it testing?  "cat /proc/cgroup"
is showing that freezer is already mounted and the kernel seems to
have correctly refused to mount it in a different hierarchy.  What am
I missing here?

Thanks.

-- 
tejun