Re: [PATCH v2] sched/isolation: add a workqueue parameter to constrain unbound CPUs

[Tejun Heo]

On Wed, Jun 14, 2023 at 05:19:45PM +0800, tiozhang wrote:
...
> @@ -181,8 +181,8 @@ static int __init housekeeping_nohz_full_setup(char *str)
>  {
>  	unsigned long flags;
>  
> -	flags = HK_FLAG_TICK | HK_FLAG_WQ | HK_FLAG_TIMER | HK_FLAG_RCU |
> -		HK_FLAG_MISC | HK_FLAG_KTHREAD;
> +	flags = HK_FLAG_TICK | HK_FLAG_TIMER | HK_FLAG_RCU | HK_FLAG_MISC
> +		| HK_FLAG_KTHREAD;

Why is WQ being taken out of nohz_full setup? The patch description doesn't
mention anything.

> @@ -208,6 +208,12 @@ static int __init housekeeping_isolcpus_setup(char *str)
>  			continue;
>  		}
>  
> +		if (!strncmp(str, "workqueue,", 10)) {
> +			str += 10;
> +			flags |= HK_FLAG_WQ;
> +			continue;
> +		}

I wonder whether it'd be better to just add a workqueue boot param but if
this works it's fine too.

Thanks.

-- 
tejun