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Date:   Mon, 19 Jun 2023 00:32:25 +0800
From:   Chen Yu <yu.c.chen@intel.com>
To:     Miaohe Lin <linmiaohe@huawei.com>
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Subject: Re: [PATCH] sched/topology: remove unneeded do while loop in
 cpu_attach_domain()
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References: <20230617081926.2035113-1-linmiaohe@huawei.com>
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On 2023-06-17 at 16:19:26 +0800, Miaohe Lin wrote:
> When sg != sd->groups, the do while loop would cause deadloop here. But
> that won't occur because sg is always equal to sd->groups now. Remove
> this unneeded do while loop.
> 
> Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
> ---
>  kernel/sched/topology.c | 5 +----
>  1 file changed, 1 insertion(+), 4 deletions(-)
> 
> diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c
> index ca4472281c28..9010c93c3fdb 100644
> --- a/kernel/sched/topology.c
> +++ b/kernel/sched/topology.c
> @@ -750,10 +750,7 @@ cpu_attach_domain(struct sched_domain *sd, struct root_domain *rd, int cpu)
>  			 * domain for convenience. Clear such flags since
>  			 * the child is being destroyed.
>  			 */
> -			do {
> -				sg->flags = 0;
I guess we don't need to clear the flag of remote groups for now.
> -			} while (sg != sd->groups);
> -
> +			sg->flags = 0;
>  			sd->child = NULL;
>  		}
>  	}
> -- 
> 2.27.0
>
Reviewed-by: Chen Yu <yu.c.chen@intel.com>

thanks,
Chenyu