Re: [PATCH v3 2/4] selftests/resctrl: Pass sysfs controller name of the vendor

[Reinette Chatre <reinette.chatre@intel.com>]

Hi Babu,

Subject and changelog mentions how controller name is "passed" but the
patch does not seem to "pass" anything new.

On 6/5/24 3:45 PM, Babu Moger wrote:
> The test detects number of memory controllers by looking at the sysfs
> file system. Detect the vendor to pass the controller name appropriately.
> So, that rest of the code will be generic and can be used to support other
> vendors.
> 
> Also change the search to look for the full string "uncore_imc_". Replace
> the sizeof with strlen.
> 
> Signed-off-by: Babu Moger <babu.moger@amd.com>
> ---
> v3: Change the search string to "uncore_imc_".
> 
> v2: No changes
> ---
>   tools/testing/selftests/resctrl/resctrl_val.c | 22 ++++++++++++-------
>   1 file changed, 14 insertions(+), 8 deletions(-)
> 
> diff --git a/tools/testing/selftests/resctrl/resctrl_val.c b/tools/testing/selftests/resctrl/resctrl_val.c
> index 2d5e961b3a68..23c0e0a1d845 100644
> --- a/tools/testing/selftests/resctrl/resctrl_val.c
> +++ b/tools/testing/selftests/resctrl/resctrl_val.c
> @@ -10,7 +10,7 @@
>    */
>   #include "resctrl.h"
>   
> -#define UNCORE_IMC		"uncore_imc"
> +#define UNCORE_IMC		"uncore_imc_"
>   #define READ_FILE_NAME		"events/cas_count_read"
>   #define WRITE_FILE_NAME		"events/cas_count_write"
>   #define DYN_PMU_PATH		"/sys/bus/event_source/devices"
> @@ -206,24 +206,30 @@ static int num_of_mem_controllers(void)
>   	char mc_dir[512], *temp;
>   	unsigned int count = 0;
>   	struct dirent *ep;
> -	int ret;
> +	char *sysfs_name;
> +	int ret, vendor;
>   	DIR *dp;
>   
> +	vendor = get_vendor();

get_vendor() is already optimized to only need to do actual detection once.
I thus do not see a need for a local variable.

> +	if (vendor == ARCH_INTEL) {
> +		sysfs_name = UNCORE_IMC;
> +	} else {
> +		ksft_perror("Unsupported vendor!\n");

ksft_perror() also adds a "\n" so adding it here is not necessary. Also
please drop the exclamation.

> +		return -1;
> +	}
> +
>   	dp = opendir(DYN_PMU_PATH);
>   	if (dp) {
>   		while ((ep = readdir(dp))) {
> -			temp = strstr(ep->d_name, UNCORE_IMC);
> +			temp = strstr(ep->d_name, sysfs_name);
>   			if (!temp)
>   				continue;
>   
>   			/*
>   			 * imc counters are named as "uncore_imc_<n>", hence
> -			 * increment the pointer to point to <n>. Note that
> -			 * sizeof(UNCORE_IMC) would count for null character as
> -			 * well and hence the last underscore character in
> -			 * uncore_imc'_' need not be counted.
> +			 * increment the pointer to point to <n>.
>   			 */
> -			temp = temp + sizeof(UNCORE_IMC);
> +			temp = temp + strlen(sysfs_name);
>   
>   			/*
>   			 * Some directories under "DYN_PMU_PATH" could have

Reinette