On Tue, Apr 26, 2022 at 10:03:20PM +0200, Armin Wolf wrote:
> If a particular SMM call takes a very long time to execute,
> the user might experience audio problems. Print a warning
> if a particular SMM call took over 0.250 seconds to execute,
> so the user can check whether or not possible audio problems
> are caused by this driver.
>
> Signed-off-by: Armin Wolf <W_Armin@xxxxxx>
> ---
> drivers/hwmon/dell-smm-hwmon.c | 6 ++++++
> 1 file changed, 6 insertions(+)
>
> diff --git a/drivers/hwmon/dell-smm-hwmon.c b/drivers/hwmon/dell-smm-hwmon.c
> index f13902414615..b960330eaded 100644
> --- a/drivers/hwmon/dell-smm-hwmon.c
> +++ b/drivers/hwmon/dell-smm-hwmon.c
> @@ -49,6 +49,9 @@
> #define I8K_SMM_GET_DELL_SIG1 0xfea3
> #define I8K_SMM_GET_DELL_SIG2 0xffa3
>
> +/* in usecs */
> +#define DELL_SMM_MAX_DURATION 250000
> +
> #define I8K_FAN_MULT 30
> #define I8K_FAN_RPM_THRESHOLD 1000
> #define I8K_MAX_TEMP 127
> @@ -239,6 +242,9 @@ static int i8k_smm_func(void *par)
> pr_debug("smm(0x%.4x 0x%.4x) = 0x%.4x (took %7lld usecs)\n", eax, ebx,
> (rc ? 0xffff : regs->eax & 0xffff), duration);
>
> + if (duration > DELL_SMM_MAX_DURATION)
> + pr_warn("SMM call took %lld usecs!\n", duration);
pr_warn_once, maybe ? If this happens, it will happen a lot, and it doesn't
add much if any value to keep reporting the problem.
Guenter
