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Message-ID: <9e2772e3-f615-5e80-6922-5a2dd06a8b07@redhat.com>
Date:   Wed, 18 Oct 2023 09:30:04 -0400
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Subject: Re: [PATCH-cgroup 3/4] cgroup/cpuset: Keep track of CPUs in isolated
 partitions
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To:     Tejun Heo <tj@kernel.org>
Cc:     Zefan Li <lizefan.x@bytedance.com>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Jonathan Corbet <corbet@lwn.net>,
        Lai Jiangshan <jiangshanlai@gmail.com>,
        Shuah Khan <shuah@kernel.org>, cgroups@vger.kernel.org,
        linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-kselftest@vger.kernel.org
References: <20231013181122.3518610-1-longman@redhat.com>
 <20231013181122.3518610-4-longman@redhat.com>
 <ZS-kt6X5Dd1lktAw@slm.duckdns.org>
From:   Waiman Long <longman@redhat.com>
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On 10/18/23 05:26, Tejun Heo wrote:
> On Fri, Oct 13, 2023 at 02:11:21PM -0400, Waiman Long wrote:
> ...
>> @@ -3875,6 +3931,13 @@ static struct cftype dfl_files[] = {
>>   		.flags = CFTYPE_ONLY_ON_ROOT | CFTYPE_DEBUG,
>>   	},
>>   
>> +	{
>> +		.name = "cpus.isolated",
>> +		.seq_show = cpuset_common_seq_show,
>> +		.private = FILE_ISOLATED_CPULIST,
>> +		.flags = CFTYPE_ONLY_ON_ROOT | CFTYPE_DEBUG,
>> +	},
> I'd much rather show this in a wq sysfs file along with other related masks,
> and not in a DEBUG file.

It can certainly be exposed as a permanent addition to the cgroup 
control files instead of a debug only file. However this set of isolated 
CPUs may be used by others not just by workqueue. So I doubt if it 
should be a sysfs file in the workqueue directory. I can see if it is 
possible to put a symlink there point back to the cgroupfs.

Thanks,
Longman