Re: [PATCH v3 4/5] selftests/resctrl: Add resource_info_file_exists()

[Ilpo Järvinen]

On Thu, 25 Jan 2024, Maciej Wieczor-Retman wrote:

> Feature checking done by resctrl_mon_feature_exists() covers features
> represented by the feature name presence inside the 'mon_features' file
> in /sys/fs/resctrl/info/L3_MON directory. There exists a different way
> to represent feature support and that is by the presence of 0 or 1 in a
> single file in the info/resource directory. In this case the filename
> represents what feature support is being indicated.
> 
> Add a generic function to check file presence in the
> /sys/fs/resctrl/info/<RESOURCE> directory.
> 
> Signed-off-by: Maciej Wieczor-Retman <maciej.wieczor-retman@xxxxxxxxx>
> ---
> Changelog v3:
> - Split off the new function into this patch. (Reinette)
> 
> Changelog v2:
> - Add this patch.
> 
>  tools/testing/selftests/resctrl/resctrl.h   |  2 ++
>  tools/testing/selftests/resctrl/resctrlfs.c | 26 +++++++++++++++++++++
>  2 files changed, 28 insertions(+)
> 
> diff --git a/tools/testing/selftests/resctrl/resctrl.h b/tools/testing/selftests/resctrl/resctrl.h
> index 4603b215b97e..c39105f46da9 100644
> --- a/tools/testing/selftests/resctrl/resctrl.h
> +++ b/tools/testing/selftests/resctrl/resctrl.h
> @@ -138,6 +138,8 @@ int umount_resctrlfs(void);
>  int validate_bw_report_request(char *bw_report);
>  bool resctrl_resource_exists(const char *resource);
>  bool resctrl_mon_feature_exists(const char *feature);
> +bool resource_info_file_exists(const char *resource,
> +			       const char *feature);
>  bool test_resource_feature_check(const struct resctrl_test *test);
>  char *fgrep(FILE *inf, const char *str);
>  int taskset_benchmark(pid_t bm_pid, int cpu_no, cpu_set_t *old_affinity);
> diff --git a/tools/testing/selftests/resctrl/resctrlfs.c b/tools/testing/selftests/resctrl/resctrlfs.c
> index e4ba8614fb7b..a6427732e0ad 100644
> --- a/tools/testing/selftests/resctrl/resctrlfs.c
> +++ b/tools/testing/selftests/resctrl/resctrlfs.c
> @@ -763,6 +763,32 @@ bool resctrl_mon_feature_exists(const char *feature)
>  	return !!res;
>  }
>  
> +/*
> + * resource_info_file_exists - Check if a file is present inside
> + * /sys/fs/resctrl/info/RESOURCE.
> + * @resource:	Required resource (Eg: MB, L3, L2, etc.)
> + * @feature:	Required feature.
> + *
> + * Return: True if the file exists, else false.
> + */
> +bool resource_info_file_exists(const char *resource,
> +			       const char *feature)

Fits to one line.

> +{
> +	char res_path[PATH_MAX];
> +	struct stat statbuf;
> +
> +	if (!feature || !resource)
> +		return false;
> +
> +	snprintf(res_path, sizeof(res_path), "%s/%s/%s", INFO_PATH, resource,
> +		 feature);
> +
> +	if (stat(res_path, &statbuf))
> +		return false;
> +
> +	return true;
> +}
> +
>  bool test_resource_feature_check(const struct resctrl_test *test)
>  {
>  	return resctrl_resource_exists(test->resource);
> 

Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>

-- 
 i.