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Subject: Re: [syzbot] possible deadlock in worker_thread
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To:     Bart Van Assche <bvanassche@acm.org>,
        Haakon Bugge <haakon.bugge@oracle.com>
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        Lai Jiangshan <jiangshanlai@gmail.com>
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From:   Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
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On 2022/02/16 2:05, Bart Van Assche wrote:
> On 2/15/22 04:48, Tetsuo Handa wrote:
>> I do not want to do like
>>
>> -    system_wq = alloc_workqueue("events", 0, 0);
>> +    system_wq = alloc_workqueue("events", __WQ_SYSTEM_WIDE, 0);
>>
>> because the intent of this change is to ask developers to create their own WQs.
> 
> I want more developers to use the system-wide workqueues since that reduces memory usage. That matters for embedded devices running Linux.

Reserving a kernel thread for WQ_MEM_RECLAIM WQ might consume some memory,
but I don't think that creating a !WQ_MEM_RECLAIM WQ consumes much memory.