Re: [PATCH] psi: fix randomized calculation in record_times()

[Johannes Weiner]

On Fri, Apr 03, 2020 at 04:55:25AM -0400, Yafang Shao wrote:
> @@ -690,7 +690,10 @@ static void psi_group_change(struct psi_group *group, int cpu,
>  	 */
>  	write_seqcount_begin(&groupc->seq);
>  
> -	record_times(groupc, cpu, false);
> +	if (groupc->total_tasks)
> +		record_times(groupc, cpu, false);
> +	else
> +		groupc->state_start = cpu_clock(cpu);

This change appears is a no-op. If there are no tasks,
groupc->state_mask is 0, and the only thing record_times() does is

	groupc->state_start = cpu_clock(cpu);

Did you encounter actual problems, or are you just reading the code?