Re: [PATCH v3 08/12] amd-pstate-ut: Add ability to run a single testcase

[Mario Limonciello (AMD) (kernel.org)]

On 3/20/2026 9:43 AM, Gautham R. Shenoy wrote:
> Currently when amd-pstate-ut test module is loaded, it runs all the
> tests from amd_pstate_ut_cases[] array.
>
> Add a module parameter named "run_only" that allows users to run a
> single test from the array by specifying the test name string.
>
> Signed-off-by: Gautham R. Shenoy <gautham.shenoy@xxxxxxx>
> ---
>   drivers/cpufreq/amd-pstate-ut.c | 11 ++++++++++-
>   1 file changed, 10 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/cpufreq/amd-pstate-ut.c b/drivers/cpufreq/amd-pstate-ut.c
> index 447b9aa5ce40..35e453a49c0f 100644
> --- a/drivers/cpufreq/amd-pstate-ut.c
> +++ b/drivers/cpufreq/amd-pstate-ut.c
> @@ -35,6 +35,10 @@
>   
>   #include "amd-pstate.h"
>   
> +static char *run_only;
> +module_param(run_only, charp, 0444);
> +MODULE_PARM_DESC(run_only,
> +	"Run only the named test case (default: run all)");

This default shows the end effect; but it doesn't make sense for this 
parameter IMO.

How about instead if you had a semicolon delimitted list and then 
defaulted an empty list to mean all tests?  Something like this:

static char *test_list;
module_param(test_list, charp, 0444)
MODULE_PARM_DESC(test_list,
	"Semicolon delimitted list of tests to run (empty means run all tests)");

>   
>   struct amd_pstate_ut_struct {
>   	const char *name;
> @@ -275,7 +279,12 @@ static int __init amd_pstate_ut_init(void)
>   	u32 i = 0, arr_size = ARRAY_SIZE(amd_pstate_ut_cases);
>   
>   	for (i = 0; i < arr_size; i++) {
> -		int ret = amd_pstate_ut_cases[i].func(i);
> +		int ret;
> +
> +		if (run_only && strcmp(run_only, amd_pstate_ut_cases[i].name))
> +			continue;
> +
> +		ret = amd_pstate_ut_cases[i].func(i);

If you take my suggestion then you would split this on semicolon or end 
of string and then allow matching multiple.

>   
>   		if (ret)
>   			pr_err("%-4d %-20s\t fail: %d!\n", i+1, amd_pstate_ut_cases[i].name, ret);