On Sun, Apr 27, 2025 at 4:35 AM Su Hui <suhui@xxxxxxxxxxxx> wrote:
>
> 'clockid' only can be ALARM_REALTIME and ALARM_BOOTTIME. It's impossible
> to return -1 and callers never check the value of -1.
>
> Only alarm_clock_get_timespec(), alarm_clock_get_ktime(),
> alarm_timer_create() and alarm_timer_nsleep() call clock2alarm(). These
> callers using clockid_to_kclock() to get 'struct k_clock', this ensures
> clock2alarm() never returns -1.
>
> Signed-off-by: Su Hui <suhui@xxxxxxxxxxxx>
> ---
> v2:
> - No Change.
> kernel/time/alarmtimer.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
> index 0ddccdff119a..e5450a77ada9 100644
> --- a/kernel/time/alarmtimer.c
> +++ b/kernel/time/alarmtimer.c
> @@ -515,9 +515,9 @@ static enum alarmtimer_type clock2alarm(clockid_t clockid)
> {
> if (clockid == CLOCK_REALTIME_ALARM)
> return ALARM_REALTIME;
> - if (clockid == CLOCK_BOOTTIME_ALARM)
> - return ALARM_BOOTTIME;
> - return -1;
> +
> + /* CLOCK_BOOTTIME_ALARM case */
> + return ALARM_BOOTTIME;
So, I think your change is a good one, as the error case of -1 is never checked.
But it might be worth adding a WARN_ON_ONCE() if the clockid isn't
CLOCK_REALTIME_ALARM or CLOCK_BOOTTIME_ALARM, just so there aren't any
surprises if someone misuses the function.
thanks
-john
