Re: [PATCH v3 6/9] cpu/SMT: Allow enabling partial SMT states via sysfs

From: Zhang, Rui
Date: Tue Jul 04 2023 - 23:15:09 EST


On Thu, 2023-06-29 at 16:31 +0200, Laurent Dufour wrote:
> @@ -2580,6 +2597,17 @@ static ssize_t control_show(struct device
> *dev,
>  {
>         const char *state = smt_states[cpu_smt_control];
>  
> +#ifdef CONFIG_HOTPLUG_SMT
> +       /*
> +        * If SMT is enabled but not all threads are enabled then
> show the
> +        * number of threads. If all threads are enabled show "on".
> Otherwise
> +        * show the state name.
> +        */
> +       if (cpu_smt_control == CPU_SMT_ENABLED &&
> +           cpu_smt_num_threads != cpu_smt_max_threads)
> +               return sysfs_emit(buf, "%d\n", cpu_smt_num_threads);
> +#endif
> +

My understanding is that cpu_smt_control is always set to
CPU_SMT_NOT_IMPLEMENTED when CONFIG_HOTPLUG_SMT is not set, so this
ifdef is not necessary, right?

thanks,
rui