Function k_timer_cleanup 

pub unsafe extern "C" fn k_timer_cleanup(timer: *mut k_timer) -> i32

@brief Clean up a dynamically allocated timer before freeing it.

If a k_timer object is dynamically allocated, its timeout must be cancelled and any in-flight expiration handler must complete before the storage may be freed – otherwise the handler dereferences freed memory. This function performs both: it removes the timer from the timeout queue and waits for any in-flight handler on another CPU to finish.

Unlike k_timer_stop(), this function does not invoke the user stop_fn callback and does not touch the wait queue: if the function returns 0 the caller assumes responsibility for the storage and there is no other consumer of the timer left.

@param timer Address of the timer. @retval 0 on success. @retval -EAGAIN when threads are still pending on the timer’s wait queue (e.g. via k_timer_status_sync()).