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Date:   Thu, 22 Sep 2022 10:47:14 -0700
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Subject: Re: [PATCH 4/5] selftests/resctrl: Kill the child process before
 exiting the parent process if an exception occurs
Content-Language: en-US
To:     Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>,
        Fenghua Yu <fenghua.yu@intel.com>,
        Shuah Khan <shuah@kernel.org>
CC:     <linux-kernel@vger.kernel.org>, <linux-kselftest@vger.kernel.org>
References: <20220914015147.3071025-1-tan.shaopeng@jp.fujitsu.com>
 <20220914015147.3071025-6-tan.shaopeng@jp.fujitsu.com>
From:   Reinette Chatre <reinette.chatre@intel.com>
In-Reply-To: <20220914015147.3071025-6-tan.shaopeng@jp.fujitsu.com>
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Hi Shaopeng,

On 9/13/2022 6:51 PM, Shaopeng Tan wrote:

...

> @@ -218,11 +219,11 @@ int cat_perf_miss_val(int cpu_no, int n, char *cache_type)
>  			}
>  		}
>  		close(pipefd[0]);
> -		kill(bm_pid, SIGKILL);
>  	}
>  
> -	if (bm_pid)
> -		umount_resctrlfs();
> +out:
> +	kill(bm_pid, SIGKILL);
> +	umount_resctrlfs();
>  

From what I can tell both parent and child will now run this code. So
both will attempt to unmount resctrl fs and the child will attempt
to kill PID 0?

Reinette