Re: [PATCH v5 13/16] selftests/resctrl: Convert ctrlgrp & mongrp to pointers

[Reinette Chatre <reinette.chatre@xxxxxxxxx>]

Hi Ilpo,

On 5/31/24 6:11 AM, Ilpo Järvinen wrote:
> The struct resctrl_val_param has control and monitor groups as char
> arrays but they are not supposed to be mutated within resctrl_val().
>
> Convert the ctrlgrp and mongrp char array within resctrl_val_param to
> plain const char pointers and adjust the strlen() based checks to
> check NULL instead.
>
> Convert !grp_name check in create_grp() into internal sanity check by
> returning error if the caller asked to create a group but doesn't
> provide a name for the group. The existing code already abides this by
> only calling create_grp() if mongrp is non-NULL so the error should
> never be returned with the current selftests (ctrlgrp is never NULL).

This paragraph is no longer relevant and can be dropped.

> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>
> ---
> v5:
> - Return 0 if grp_name is null (restore earlier behavior)
> - Move the root group note from comment into kerneldoc
>
> v3:
> - Removed wrong comment
> - Changed grp_name check to return -1 on fail (internal sanity check)
> ---
>   tools/testing/selftests/resctrl/resctrl.h   |  4 ++--
>   tools/testing/selftests/resctrl/resctrlfs.c | 16 +++++++---------
>   2 files changed, 9 insertions(+), 11 deletions(-)
>
> diff --git a/tools/testing/selftests/resctrl/resctrl.h b/tools/testing/selftests/resctrl/resctrl.h
> index 5967389038d4..a999fbc13fd3 100644
> --- a/tools/testing/selftests/resctrl/resctrl.h
> +++ b/tools/testing/selftests/resctrl/resctrl.h
> @@ -91,8 +91,8 @@ struct resctrl_test {
>    */
>   struct resctrl_val_param {
>   	char		*resctrl_val;
> -	char		ctrlgrp[64];
> -	char		mongrp[64];
> +	const char	*ctrlgrp;
> +	const char	*mongrp;
>   	char		filename[64];
>   	unsigned long	mask;
>   	int		num_of_runs;
> diff --git a/tools/testing/selftests/resctrl/resctrlfs.c b/tools/testing/selftests/resctrl/resctrlfs.c
> index f4dc8ef23a8c..893041faaf18 100644
> --- a/tools/testing/selftests/resctrl/resctrlfs.c
> +++ b/tools/testing/selftests/resctrl/resctrlfs.c
> @@ -456,6 +456,9 @@ int taskset_restore(pid_t bm_pid, cpu_set_t *old_affinity)
>    * @grp:	Full path and name of the group
>    * @parent_grp:	Full path and name of the parent group
>    *
> + * Creates a group @grp_name if it does not exist yet. If @grp_name is NULL,
> + * it is interpreted as the root group which always results success.

"always results success" -> "always results in success"?

With changelog and comment fixups addressed:
| Reviewed-by: Reinette Chatre <reinette.chatre@xxxxxxxxx>

Reinette