Re: [PATCH 2/5] cgroup/cpuset: Add new cpus.partition type with no load balancing

[Tejun Heo <tj@kernel.org>]

Hello,

Generally looks fine to me.

On Thu, Jun 03, 2021 at 05:24:13PM -0400, Waiman Long wrote:
> @@ -1984,12 +1987,31 @@ static int update_prstate(struct cpuset *cs, int val)
>  			goto out;
>  
>  		err = update_parent_subparts_cpumask(cs, partcmd_enable,
> -						     NULL, &tmp);
> +						     NULL, &tmpmask);
> +
>  		if (err) {
>  			update_flag(CS_CPU_EXCLUSIVE, cs, 0);
>  			goto out;
> +		} else if (new_prs == PRS_ENABLED_NOLB) {
> +			/*
> +			 * Disable the load balance flag should not return an

                                 ^ing

and "else if" after "if (err) goto out" block is weird. The two conditions
don't need to be tied together.

> @@ -2518,6 +2547,9 @@ static int sched_partition_show(struct seq_file *seq, void *v)
>  	case PRS_ENABLED:
>  		seq_puts(seq, "root\n");
>  		break;
> +	case PRS_ENABLED_NOLB:
> +		seq_puts(seq, "root-nolb\n");
> +		break;
>  	case PRS_DISABLED:
>  		seq_puts(seq, "member\n");
>  		break;
> @@ -2544,6 +2576,8 @@ static ssize_t sched_partition_write(struct kernfs_open_file *of, char *buf,
>  		val = PRS_ENABLED;
>  	else if (!strcmp(buf, "member"))
>  		val = PRS_DISABLED;
> +	else if (!strcmp(buf, "root-nolb"))
> +		val = PRS_ENABLED_NOLB;
>  	else
>  		return -EINVAL;

I wonder whether there's a better name than "root-nolb" because nolb isn't
the most readable and we are using space as the delimiter for other names.
Would something like "isolated" work?

Thanks.

-- 
tejun