Re: [RFC] blkio_delay_total is calculated mistakenly

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From	Weiwei Jia <harrynjit@gmail.com>
Newsgroups	linux.kernel
Subject	Re: [RFC] blkio_delay_total is calculated mistakenly
Date	Wed, 15 Feb 2017 04:20:01 +0100
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On Tue, Feb 14, 2017 at 10:00 PM, Greg KH <gregkh@linuxfoundation.org> wrote:
> On Tue, Feb 14, 2017 at 08:27:36PM -0500, Weiwei Jia wrote:
>> Hi,
>>Balbir Singh <bsingharora@gmail.com>
>> When I read Linux Kernel source codes about how "blkio_delay_total"
>> (delay waiting for synchronous block I/O to complete for one task) is
>> calculated in Linux/kernel/delayacct.c file [1], I find that
>> "blkio_delay_total" adds "task->delays->blkio_delay" to be the total
>> delay time for one task to wait for synchronous I/O dynamically but
>> "tsk->delays->blkio_delay" has already been calculated as the total
>> delay time that one task is waiting for synchronous I/O [2]
>> dynamically. I think "blkio_delay_total" should not add
>> "task->delays->blkio_delay" since "task->delays->blkio_delay" is
>> already the total delay time we want.
>>
>> Am I missing anything?
>
> Why are you sending this to me?  You have read
> Documentation/SubmittingPatches, right?
>
> Please use scripts/get_maintainers.pl for who to send patches to.

Okay. Have cc'ed Balbir Singh <bsingharora@gmail.com> already.

Thanks,
Weiwei Jia

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Thread

[RFC] blkio_delay_total is calculated mistakenly Weiwei Jia <harrynjit@gmail.com> - 2017-02-15 02:30 +0100
  Re: [RFC] blkio_delay_total is calculated mistakenly Greg KH <gregkh@linuxfoundation.org> - 2017-02-15 04:10 +0100
    Re: [RFC] blkio_delay_total is calculated mistakenly Weiwei Jia <harrynjit@gmail.com> - 2017-02-15 04:20 +0100

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