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Subject: Re: [PATCH] kthread: Export kthread_data()
From: Waiman Long <longman@redhat.com>
To: Christoph Hellwig <hch@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Tejun Heo <tj@kernel.org>, Ingo Molnar <mingo@kernel.org>,
        linux-kernel@vger.kernel.org
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 <20180213155033.GA16684@infradead.org>
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Date: Tue, 13 Feb 2018 16:42:00 -0500
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On 02/13/2018 04:40 PM, Waiman Long wrote:
> On 02/13/2018 10:50 AM, Christoph Hellwig wrote:
>> On Fri, Feb 09, 2018 at 09:52:21AM -0500, Waiman Long wrote:
>>> When multiple kernel threads are created to cooperatively work on
>>> a common task, we may need a convenient way to access data that are
>>> specific to each kthread.
>>>
>>> The kthread_data() function fits this need.  However, it was not
>>> visible to kthreads started in a kernel module. To solve this problem,
>>> the kthread_data() function is now exported allowing kthreads from
>>> kernel modules to use it.
>> Please send this along wit hthe actual user of it.
> It is the developers of the dm-vdo/kvdo modules that would like to use
> the kthread_data() function. See
>
> https://github.com/dm-vdo/kvdo
>
> Those modules have a bunch of kernel threads working on block storage
> deduplication/compression.
>
> -Longman
>
BTW, I am fine with not exporting the function. They just have to find
an alternative way of doing it.

-Longman