[LTP] [PATCH v3 2/3] tst_cgroup: Add safe_cg_open and safe_cg_fchown functions

[xuyang2018.jy@fujitsu.com]

Hi Richard

> 
> Richard Palethorpe <rpalethorpe@suse.de> writes:
> 
>> Hello,
>>
>> Yang Xu <xuyang2018.jy@fujitsu.com> writes:
>>
>>> safe_cg_open is used to open the sub control's file ie cgroup.procs
>>> and returns the opened fd number. The opened fd array is stored in
>>> fds argument.
>>>
>>> safe_cg_fchown is used to use fchownat to change file's uid and gid.
>>>
>>> Signed-off-by: Yang Xu <xuyang2018.jy@fujitsu.com>
>>> ---
>>>   include/tst_cgroup.h | 44 +++++++++++++++++++++++++++++
>>>   lib/tst_cgroup.c     | 66 +++++++++++++++++++++++++++-----------------
>>>   2 files changed, 85 insertions(+), 25 deletions(-)
>>>
>>> diff --git a/include/tst_cgroup.h b/include/tst_cgroup.h
>>> index d06847cc6..70c5b3fd4 100644
>>> --- a/include/tst_cgroup.h
>>> +++ b/include/tst_cgroup.h
>>> @@ -89,6 +89,32 @@ enum tst_cg_ver {
>>>   	TST_CG_V2 = 2,
>>>   };
>>>   
>>> +/* Controller sub-systems */
>>> +enum cgroup_ctrl_indx {
>>> +	CTRL_MEMORY = 1,
>>> +	CTRL_CPU,
>>> +	CTRL_CPUSET,
>>> +	CTRL_IO,
>>> +	CTRL_PIDS,
>>> +	CTRL_HUGETLB,
>>> +	CTRL_CPUACCT,
>>> +	CTRL_DEVICES,
>>> +	CTRL_FREEZER,
>>> +	CTRL_NETCLS,
>>> +	CTRL_NETPRIO,
>>> +	CTRL_BLKIO,
>>> +	CTRL_MISC,
>>> +	CTRL_PERFEVENT,
>>> +	CTRL_DEBUG
>>> +};
>>> +
>>> +#define CTRLS_MAX CTRL_DEBUG
>>> +
>>> +/* At most we can have one cgroup V1 tree for each controller and one
>>> + * (empty) v2 tree.
>>> + */
>>> +#define ROOTS_MAX (CTRLS_MAX + 1)
>>
>> These need TST_CG_ prepending to them to stop name collisions.
> 
> Actually, I think the easiest thing to do is not export these. Instead
> you could leave these alone and export "#define TST_CG_ROOTS_MAX 32".

Yes, I forgot ltp name rules when export it.

Will use  TST_CG_ROOTS_MAX in v4  and add your reviewed-by.


Best Regards
Yang Xu
> 
> The rest of the patch-set looks great.
>